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ITRODUCTIO It has been observed that all those senior & junior specialist working in state govt. in all dept. are already post graduate long back & when they Become senior & junior specialist they are already having 10-12 year’s & with in this time leg & advancement in skills & technology leaves them behind Unskilled, frustrated, & nothing doing with is a shear wastage of time, skill technology & money & great loss to humanity & society both hence it has been programme to provide them necessary skill technology & training programme.
OBJECTIVES 1. To get acquainted with various procedures of Broncoscopy, Ear and Larynx Microsurgery. 2. How to avoid complications?
3. To know use and care of Instrument in Ear, Broncoscopy and Larynx.
Suggested Reading Material 1. Scottl. Brown 2. Jacson & Jacson for Bronchoesophgoscopy. 3. Ballinger 4. Cummignn’s 5. Paperalla 6. Logan & turnur 7. Ugo fisih 8. Wolfermen 9. Mawson’s 10. Moor’s Anatomy.
Bronchoscopy Anatomy Development The respiratory system develops from a midline diverticulum in the foregut called the laryngotracheal groove, which first appears in embryos of about 3mm crown-rump length (about 25 days). Three periods have been recognized (Emery,1969); a ‘glandular’ period when the primitive bronchi ramify through the mesenchyme (up to 4 months); a ‘canicular’ period when the primitive respiratory bronchioles, recognized by the presence of cuboidal cells, are generated from the terminal bronchi (4-6 months); and an ‘alveolar’ period from 6 months onwards when further respiratory bronchioles and the terminal alveoli, which will be the functional airspaces with their blood-air barriers, are formed. The Trachea The Trachea extends downwards from the lower part of the larynx at the level of the sixth cervical vertebral body, into the mediastinum, where it bifurcates into the right and left main bronchi. The bifurcation is described as being at the level of the upper border of the fifth thoracic vertebra, but a more practical, because easily determinable, level is that of the 2nd costal cartilage, or the manubrio-sternal angle. The Trachea of the child is relatively smaller than that of the audit, and the bifurcation is at a higher level until the age of 1012 years. The length of the trachea is about 11cm, with a range of 9-15cm. the carina is a convenient practical point at which the bifurcation can be localized, and is usually 25-27 cm from the upper incisor teeth or alveolar margin. Being D-shaped in cross section rather than cylindrical, the transverse diameter is greater than the antero-posterior (about 20 mm in the adult male compared with 15mm.)
The cartilaginous ring of the trachea and main baronchi are incomplete segments of a circle, so that the trachea in crosssection is shaped like the letter D, the straight limb being posteriorly situated and formed by the membranous wall. The lumen of the trachea is indented on the left and anteriorly in its lower portion by the arch of the aorta, this deformity being exaggerated if the aorta is dilated.
DAIGRAM
Structure: The trachea is a membranous tube about 11 cm in length and containing about 16-20 incomplete rings of cartilage which serve to stiffen its wall anteriorly and laterally the wall consists of a mucosal layer, a submucosal layer and an outer layer composed of fibrous tissue, smooth muscle and the cartilage. The mucosa consists of a pseudostratified ciliated columnar epithelium with numerous goblet cells resting on a broad basement membrane. The submucosa consists of a layer of loose fatty connective tissue which extends to the perichondrium of the tracheal rings. It is probable that the serous secretion forms a film of fluid in which the cilia can move freely as they sweep the mucus upwards to the larynx and pharynx. The secretions of the tracheal glands and the addition of transudate raises the relative humidity
of the air reaching the alveoli to 100 percent (Negus, 1958) The outer fibrous and muscular layer is continuous with the loose areolar tissue of the mediastinum and contains blood and lymphatic vessels as well as nerves. It is continuous with the perichondrium of the cartilages. The latter are incomplete rings occupying the anterior two-thirds of the circumference of the trachea. Blood and erve supply The blood supply of the trachea is derived form branches of the inferior thyroid arteries; at lower and branches from bronchial arteries also contribute. The tracheal veins drain into the thyroid venous plexus. The lymphatic drainage is to the pre-trachealis and pre-tracheal groups of n odes. The muscle fibers of the trachea, including the trachealis muscle, are innervated by the recurrent laryngeal nerves, which also carry sensory fibers from the mucous membrane. Sympathetic nerve fibers come mainly form the middle cervical ganglion and they also have connections with the recurrent laryngeal nerves. The Bronchi and the bronchial tree In the adult the trachea bifurcates into the right and the left main bronchi at the level of the second costal cartilage. The main bronchi are separated by carina. omenclature of the bronchial tree Ten major segments in the right lung and eight in the left. The right main bronchus The right main bronchus is wider and more nearly vertical than the left, being much more nearly a continuation of the line of the trachea. The right main bronchus ends at the orifice of the middle love bronchus and is about 5 cm in length. It has a posterior membranous wall, and a series of cartilage rings very similar in
structure though smaller in size than those of the trachea. The right upper love bronchus opens almost directly laterally about 1.02 -2.0 cm from the carina. The average angle made by the right main bronchus with the trachea is given by Tuner (1962) as about 30 degrees, with a range of 13-44 degrees. The coronal diameter of the right main bronchus is about 17+- 4 mm in the male and about 15-+4 mm in the female; the corresponding diameter on the left side is 2-3 mm. It has already been noted that the right main bronchus is m ore nearly in line with the trachea than is t he left. For this reason it is easier for inhaled foreign bodies or fluids much as gastric contents to enter the right rather than the left bronchial tree. If the patients should be lying on his side it is natural for fluids, including infected mucus from the upper respiratory tract, to enter the upper love bronchi. It is also easier for such material to enter the lateral or ‘axillary’ sub segment of the anterior and posterior segments of the lobe.
DAIGRAM
The left main bronchus The left main bronchus is longer and narrower than the right and it curves markedly away from the line of the aorta. Turner (1962) gives its angle with the trachea as being on average 43.8 degrees, with a arrange of 25-58 degrees. There is thus a very marked degree of variation in alignment. It is about 5.5 cm in length and ends by the division into upper and lower lobar divisions. It enters the lung at about the level of the 6th thoracic vertebra. Right Lung Right Upper Lobe (RUL) Apical Segment Posterior Segment Anterior Segment Right Middle Lobe (RML) Lateral segment Medial segment Right Lower Lobe (RLL) Apical segment Medial basal segment Anterior basal segment Lateral basal segment Posterior basal segment
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
Left Lung Left Upper Lobe (LUL) Apico-Posterior segment
(1+2)
Anterior segment Ligual Superior segment Inferior segment Left Lower Lobe (LLL) Apical segment
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Anterior basal segment Lateral basal segment Posterior basal segment
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(3) (4) (5)
Instruments and equipment Bronchoscopes; Rigid flexible fibre-optic bronchoscope Rigid Bronchoscopes: a bronchoscopes consists of a hollow brass tube, which is slanted at its distal end and which has a small handle at the proximal end. Accurately placed breathing-holes are situated in the sidewalls of the distal part of the tube, to allow respiration to take place through the bronchi which are not occupied by the bronchoscope. Various small auxiliary tubes are incorporated into the main bronchoscopic tube for the purposes of lighting and aspiration, and for insufflations of oxygen and of anaesthetic vapours. Bronchoscopes have been designed to fit the bronchi at various developmental ages and at various depths in the bronchial tree. The bronchi will not tolerate dilatation and bronchoscopes of greater diameter than the air passages to be explored should never be used as the results of the over-distension of a bronchus may be very serious and rupture is generally fatal. The diameters of the bronchoscopes are limited also by the size of the glottis and of the laryngeal cavity. In an adult the glottis is a triangle measuring approximately 12 X 22 X 22 mm, which permits the passage of a tube not exceeding 12 mm in diameter without risk of injury. Subglottic oedema may occur as a result of the passage of an instrument too large to be tolerated by this region or by too prolonged or too frequently repeated bronchoscopic examinations in a previously normal larynx. The duration of a bronchoscopic examination in a small child should never exceed 20 min, and it should be repeated only at reasonable intervals. Other causes of subglottic oedema are trauma caused by undue force or improper direction during inflicted by a foreign body during its extraction. Subglottic oedema is a serious lesion which may necessiatate early tracheostomy and which sometimes may prove fatal. The proximal third of the Negus bronchoscope; is expanded and this
affords more room for inspection and the introduction of instruments. It having a finer light carrier which is held in a groove, not a tube, so increasing the effective lumen of the bronchoscope. Bronchoscopic telescopes: are of great value in the examination of the subglottic region, the trachea and the bronchi since they give a wide angle magnified view of the area under inspection. Direct vision, 90o and retrograde telescope are available. When in use they are kept standing in a vessel containing hot water to prevent fogging when they are passed down the bronchoscope. Aspiration tubes: Jackson’s open-ended aspiration tubes and Negus’s tubes with detachable gum-elastic ends are most generally useful. Luken’s specimen collector sputum trap. An efficient suction apparatus is necessary and is usefully incorporated in an endoscopic table. Forceps: All bronchoscopic forceps are of a tubular type an dthey are so constructed that a slender tube woks over a stilette which carries spring spread jaws. To close the forceps the handle must be used so that the cannula is forced down on the jaws, causing them to approximate. The handle must not be manipulated so that the jaws are pulled into the cannula as this causes their tips to recede form the target. 1. Straight grasping forceps 2. Side curved forceps 3. Tucker forceps 4. Standard rotation forceps 5. Dangling rotation forceps 6. Sister-hook forceps 7. Long-jaw rotation forceps 8. Side cured rotation forceps 9. Double claw forceps 10. Expansile forceps
11. Fenestrated forceps 12. Ball forceps 13. Ball forceps 14. Double ring forceps 15. Gordon bead forceps 16. Approximation forceps 17. Cylindrical forceps 18. Cylindrical forceps with teeth 19. Wire-bending 20. Pin-bending forceps Anaesthesia In rigid bronchoscopy, general anaesthesia is replacing local analgesia. Local analgesia Lingnocaine into the interior of the larynx, a further 2ml are dropped between the cords into the trachea. This is better than injecting the solution through the cricothyroid membrane. General anaesthesia The anaesthetist, after inducing with thiopentone and suxamethonium, fully inflates the patient’s lungs with oxygen. The bronchoscope is then passed and the examination started. Ventilation is continued by means of the sanders technique. A biopsy should not be taken nor the bronchoscope removed until spontaneous respiration is returning. In young children, deep inhalation anaesthesia with nitrous oxide, oxygen and halothane is sufficient for a short examination and spontaneous respiration is not abolished.
Technique of rigid bronchoscopy All patients before bronchoscopy must have thorough clinical and radiological investigation and a routine examination of the nasal fossae, nasopharynx, pharynx and larynx, and they must be prepared in the usual manner for general anaesthesia. Position of the patient The patient is so placed that the head and shoulders extend beyond the table, the edge of which supports the thorax at about the midscapular region; and the head is held by an assistant or a head-rest as ma be preferred. The trachea does not pursue a horizontal course in the thorax, but is directed downwards and backwards. In order to bring the axes of the buccal cavity and pharynx into line with those of the larynx and trachea, the head and neck must be elevated so that the occiput is about 10 cm above the level of the table and the head must be extended at the atlanto-occipital joint as shown.
Introduction of the bronchoscope If bronchoscope is carried out under surface analgesia, it is essential that the procedure and the sensations to be endured shall be explained fully to the patient so that he may be freed form apprehension and in order that this cooperation may be obtained. Some laryngologists expose the glottis with a laryngoscope and pass the bronchoscope through this into the trachea; others pass the bronchoscope directly through the glottis into the trachea without the aid of a laryngoscope. In young children and infants it is always advisable to expose the glottis with a laryngoscope before passing the bronchoscope. If the bronchoscope is inserted through the laryngoscope after exposure of the glottis its handle is rotated to the right so that a full view of the left vocal cord is obtained through the bronchoscope. In this position the tip of the bronchoscope is situated in the long axis of the glottis and it can be inserted gently and easily into the trachea. When the bronchoscope has been advanced a short distance into the trachea the handle of the laryngoscope is rotated to the left, its slide is removed and the laryngoscope is then withdrawn. It the laryngoscope is to be passed directly without the aid of a laryngoscope, it should be held in the right hand by the shaft – not by the handle in a pen-like manner, and the patient’s upper lip should be retracted by the surgeon’s left index finger. The bronchoscope is inserted to the right of the anterior twothirds of the tongue and its tip is directed towards the midline when the posterior third is reached. The epiglottis is the first landmark and when this has been identified it is lifted forward on the tip of the bronchoscope to expose the glottis. The bronchoscope is then rotated to the right and so directed that a good view of the left cord is obtained, when the bronchoscope can be inserted gently into the trachea.
When the trachea is entered it is recognized as an open tube with whitish cartilaginous rings, while the expiratory blast is felt and tubular breathing is heard through the bronchoscope. The axis of the bronchoscope should be made to correspond as nearly as possible with that of the trachea; any secretion must be removed by aspiration and the walls of the trachea inspected by weaving the bronchoscope from side to side or by use of a 900 telescope which is self-illuminated. The carina is recognized as a sharp vertical spur separating the orifices of the two main bronchi. As the carina is situated to the left of the midline the lumen view of the left main bronchus is very in complete, and in order to view this adequately the tip of the bronchoscope is turned to the left while the patients head and neck are flexed slightly to the right. After identification and examination of the carina and of the main bronchial orifices, the main bronchi should be entered. It is impossible to visualize more than short length of the lumen of any tertiary bronchus through the bronchoscope. Fibre-optic bronchoscopy Description The internal guide wires enable the operator to flex the tip in tow directions depending on the model used. The bronchoscope is about 700 mm in overall length with a working length of about 600 mm, a shaft diameter of about 6 mm and internal channel diameter of about 2 mm. the instruments have a suction attachment for the internal channel and are supplied with biopsy forceps and brushes.
Technique of flexible fibre-optic bronchoscopy Fibre-optic bronchoscopies are performed by the direct transnasal route under local anaesthesia the trans-oral route may be used though this is slightly more difficult. In small children the small rigid bronchoscopy may be done under general anaesthesia. In small children, the small rigid bronchoscopy may be necessary, because the diameter of the current fibre-optic bronchoscope is such as partially to occlude the airway. The patients are fully evaluated beforehand by clinical and radiaographic examination and testing of pulmonary function, which includes as least spirometry (forced expired volume in second – FEV; forced vital capacity- FVC; peak expiratory flow rate PEFR), with arterial blood gases if hypoxaemia is suspected. Pre-medication is given, Omnopon to 20mg with Scopolamine 0.2-0.4 mg, pethidine 50-100 mg with atropine 0.3-0.6mg or diazepam 5-10 mg with atropine. The patient lies comfortable, semi recumbent on a couch with the bronchoscopist on the right side facing. Lignocaine aerosol (four percent) is sprayed into the wider nostril and sniffed back then over the pharynx and finally over the back of the tongue with an angled jet to reach the larynx. The bronchoscope is lubricated with lignocaine gel (two percent) and steered gently through the nose under direct vision and steadily to the larynx. The larynx is anaesthetized with a 2ml ‘bolus’ of lignocaine (four percent) injected through the central channel directly on to the vocal cords. This stage takes less than five minutes. The instrument is then passed gently through the larynx with a no-touch technique to avoid coughing. The larynx, the trachea, the carina and both bronchial tees are examined in a systematic manner. Biopsy-forceps and brush Flexible cupped biopsy forceps can be introduced through the central channel and multiple biopsies taken of endobronchial lesions under direct vision, or of localized or diffuse lung lesions under fluoroscopic control.
Aspiration A suction tube is connected to the internal channel of the bronchoscope via a T- piece to allow controlled intermittent suction. A sputum trap is included routinely in the line so that samples may be sent for bacteriological and cytological examination. Indication for bronchoscoy- rigid and fibre-optic An unexplained symptom such as cord palsy, haemoptysis, signs such as slowly resolving pneumonia, or abnormalities on chest xray such as lung shadow, masses or collapse should be bronchoscoped. Rigid bronchoscpy has been used principally for the diagnosis of bronchial carcinoma. Sarcoidosis, fibrosing alveolitis and tuberculosis, bronchoscope can be used for aspirating mucus plugs in post operative patients contra-indications such as cervical sopndylosis. One firm indication for rigid bronchoscopy, namely an impacted foreign body. COTRA IDICATIO (1) Aortic Aneurysm (2) Bleeding Tendencies (3) Recent Massive Haemoptysis (4) Acute Respiratory Insufficiency (5) Cardial Decomposition (6) Cervical Spinal Ankylosis (7) Trauma (8) Trismus Aftercare In Case Of Bronchoscopy For Foreign Body After care is of vital importance following bronchoscopy for foreign body especially in children. The child should be put to bed in a quiet is desirable for a few days. Sedatives however should be avoided, opium derivatives are absolutely
contraindicated in the aftercare. All of this precaution becomes especially important if the bronchoscopy is to be repeated or any other operation is to be done. The rule in the after care of children should be ‘Don’t wear the baby out’. Advisable in any case this precaution is vitally important in the event subsequent bronchoscopies should be necessary. Secretions must be aspirate if necessary and plenty of water must be given to prevent dehydration in any event but especially if fever is present. Complications and After-effects of Bronchoscopy A long retained foreign body a slight temporary rise of temperature may be expected but if will disappear in a day or two. These patients almost always have had irregular fever before bronchoscopy. Disturbance of the epithelium in the presence of pus usually permits enough absorption to elevate the temperature slightly for a few days. Surgical shock in its true form does not follow a carefully performed and time-limited bronchoscopy. Prolonged bronchoscopies or several done sat close intervals may be followed by fatal shock in fatigue resulting in deep sleep may be seen in older children after prolonged endoscopy. Fifteen minutes should be the limit in babies and thirty minutes should not be exceeded in children under, say five years of age. Drownage of the patients in His Own Secretion. The accumulation of secretions in the bronchi in case of vegetal foreign body duet to inefficiency or total absence of the cough reflex, is sometimes seen in children; it may reach a condition of impending asphyxia from drownage of the patient in his won secretions if it is not promptly detected and relieved. It is quickly and dramatically relievable by bronchoscopic or direct laryngoscopic aspiration. Frequent peroral passage of the bronchoscope for this purpose is contraindicated in babies
because of the likelihood of provoking subglottic edema. In infants and very young children laryngoscopic aspiration with silk woven aspirating tube is efficient and less irritating to the subglottic tissues. If however a serious degree of subglottic edema necessitates tracheotomy, this operation will enable the nurse to aspirate with a No. 8 F catheter, through the cannula as often as necessary, as necessary, even every few minutes for a period. If the nurse reports the child is not doing well bronchoscopy should be done immediately. In such cases an impaired percussion not can be elicited, usually at the base of one or both lungs, and a rising level of dullness may develop. In such emergencies bronchial obstruction by a crust or firm plug of exudates causing atelectasis may be found. The relief afforded by bronchscopic forceps removal of drowning accumulation in such cases is dramatic. Subglottic Edema particularly in cases of vegetal foreign body in the tracheobronchialtree of children under about two years of age. They have much loose, subglottic areolar tissue that swells quickly. Subglottic Edema occurring in a previously normal larynx may result from: 1. The use of oversized or clumsy bronchoscopes; 2. Prolonged bronchoscopy; 3. Faulty position of the patient, the axis of the tube not being in line with that of the trachea; 4. trauma from undue force or improper direction in the insertion of the bronchoscope; 5. forceful manipulation of instruments; 6. trauma inflicted in the extraction of the foreign body . The diagnosis of subglottic edema must be made without waiting for cyanosis which may never appear. Pallor restlessness and startled awakening after a few minutes sleep occurring in a child with croupy cough and indrawing around the clavicles in the intercostals spaces at suprasternal notch and at the epigastruium
call for tracheotomy which should not be left unwatched and should never be given a sedative. In the treatment of subglottic edema intubation is not usually advisable because the secretions cannot easily be expelled through the tube and postintubational stenosis may be produced. Low tracheotomy the tracheal incision always below the second ring is the sagest and best method of treatment in cases that do not yield to direct larynogoscopic aspiration.
Pitfalls in Mechanical Problems of foreign Body Removal 1. Lack of preliminary study of the problem with a duplicate of the foreign body to determine (a) what part is presenting; and (b) radiation of other parts to presenting part. 2. Attempting to remove or manipulate a foreign body in air or food passages located far beyond the tube mouth. The foreign body should always be approached with the tube mouth as closely as proper manipulations permit. Working at a distance form the tube mouth is often unsuccessful and may be dangerous. 3. Swabbing to remove secretions or to apply local anaesthetics, before study of the presentation. Blood-staining of secretions or exudates thus produced will interfere with study of the object and its relations to the tissues with which it is in contact. Local anesthetic (preferably cocaine solution because of its prompt and certain action) should be sprayed in, if needed. Secretions and exudates should be aspirated before the tube mouth is advanced too close to the site of the foreign body. 4. Traction on the presenting part without absolute certainly of the safety of such traction. 5. Too strong traction even if the operator feels sure that traction on the particular preventing part would be safe since the organization of the bronchoscopic clinic an aphorism has been “Be sure you are right, but not too sure.” 6. Incautious approach to and contact with a foreign body before study of the presenting part. This mistake may cause loss of the best opportunity for presentation or may convert a favourable presentation into a malpresetnation. 7. Overriding a foreign body. This mistake involves the same consequences as those just mentioned in connection with incautious approach. 8. Misuse of forceps, such as inclusion of tissue in the grasp. Even if no serious trauma is thus inflicted, slight injury to
mucosal capillaries will cause blood-staining of secretions or exudates, and this reddened secretion will obscure the field with a red film. 9. Misuse of forceps, such as insertion (a) regardless of location of “forceps spaces” or (b) regardless of the plane of neighbouring division spurs. 10. Rapid divulsion of a proximal stricture. Even an old fibrous stricture will yield safely to slow dilation. 11. Attempting to pull a foreign body through a stricture without preliminary dilation. An exception is in case of a foreign body of such shape as to serve itself, as an efficient dilator under slow steady but not forcible traction, as in foreign body case no. 4590. 12. Making a preliminary examination for the sloe purpose of taking a look without preparation for removal of the foreign body. Often the first view of a foreign body is the best for removal. All preparations for removal should be made on the basis of the preliminary studies hereinafter indicated. First, second, and even a third choice of probably indicated solutions of the mechanical problem should be represented by the assembly of a group of the appropriate instruments on the sterile is rare indeed that the experienced bronchoesophaglogist will fail to find the best solution for the particular case in one of his planned procedures. In the exceptional case of course the bronchoesophagologist will postpone further endoscopic work until he has developed a new solution based on observed conditions in the particular case.
Self Assessment (1)
Why the F.B. is are more common in (R) main Bronchus?
(2)
What are the cases of Subglottic Oedema post Bronchoscopy?
(3)
What is forceps space?
(4)
What are sign of tracheal foreign body?
(5)
How you will the trachea during the procedure?
(6)
What is Broncho pulmonary segment?
(7)
How many Broncho pulmonary segment on both side?
(8)
What is pancvat tumer?
(9)
Lingula contain how many segment?
(10) What are types of Anesthesia during Bronchoscopy?
GEERAL COSIDERATIOS:1. Definitions The surgical reconstruction of the tympnoossicular system (tympanoplsty) includes: myringoplasty, and ossiculoplasty. 2. Aims of Tympanoplsty 1. Eradication of disease 2. Restoration of tympanic aeration 3. Reconstruction of a sound-transformer mechanism. AESTHESIA LOCAL AESTHESIA Initial site of injection for local anesthesia Initially the needle is inserted in the postauricular sulcus and advanced anteroinferiorly. Five ml LA are administered by continuous infiltration during slow withdrawal to block the great auricular nerve. The needle is redirected through the same injection site and advanced anterosuperiourly. An additional 5 ml is given with the aim of blocking the auricular branches of the auriculotemporal nerve. Canal injections for local anesthesia GEERAL AESTHESIA Premedication: For adults of average weight (70kg), 10 mg valium (sedative) or Dolantin (meperiadine)- atropine i.m. 30 minutes before surgery.
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Inducation:Thiopental, etomidate or propofol and fentany (0.5mg). muscle relaxation with Celocurin. Intubation. Continuation:Atracurium or Pavulon for muscle relaxation. Artificial repiration with oxygennitrous oxide. Repeated injections of fentanyl or alfentanil.Regulation of depth of narcosis with enflurane or isoflurane. MYRIGOPLASTY 1. Definitions The term “tympanoplasty” implies reconstruction of the middle ear hearing mechanism with or without tympanic membrane grafting. Grafting of the tympanic membrane is generally called “myringoplasty” when the middle ear cavity is not entered and “tympanoplasty “when the surgeon works in the middle ear in the presence of an intact ossicular chain. 2. Surgical Approaches Transcanal Approach With this approach, surgery is performed through an ear speculum in the external canal. The transcanal approach is indicated when the external auditory canal is wide enough to allow complete visualization of a posterior perforation. The approach cannot be used when the anterior margin of the perforation is obscured by the overhanging canal wall. Endaural Approach For this approach, a small incision is made between the tragus and the helix. The entrance of the canal is enlarged with endaural retractors. 2
Post auricular Retroauricualr Approach The pinna and the attached retroauricular tissues are reflected anteriorly. Selection of Surgical Approach The transcanal approach is mostly used for repairing larger acute traumatic perforations. The endaural approach is selected for posterior perforations and the retroauricular approach for anterior perforations whose margins cannot be seen entirely through the intact external canal. Grafting Technique Two principle techniques are used for grafting the tympanic membrane: 1 underlay, and 2 The overlay. Underlay The presence of an anterior remnant of the tympanic membrane (at lest of the fibrous tympanic annulus) is required for this type of fascial graft. The graft is place under the anterior remnant of the tympanic membrane and over the posterior DAIGRAM tympanic sulcus. The graft lies under the malleus handle.
3
Overlay This techniques is used when there is no remnant of the tympanic membrane. The graft rests over the sulcus and underneath the malleus handle. The edges of the graft are covered by metal skin.
DAIGRAM
Retroauricular Approach Surgical Technique. The retroauricular approach is mainly used for anterior perforations with margins. SKI ICISIO The presence of an anterior Remnant of the tympanic membrane (at lest of the fibrous tympanic annulus) DAIGRAM is required for this type of fascial graft. The graft is placed under the anterior Remnant of the tympanic membrane And over the posterior tympanic sulcus. The graft lies under the malleus handle. 4
The retroauricular skin incision is carried out along the hairline and is made only through skin, preserving the underlying fascia and periostium. Periosted flap Following elevation of the skin, a retroauricular periosteal flap is formed. This flap will be repositioned and sutured to the surrounding soft tissues at the end of surgery. The periosteal flp may also be used to cover the posterior surface of the canal wall when a mastoidectomy is performed. Exposure of the external auditory canal The periosteal flap is elevated from the bone with a mastoid raspatory. The posterior limb of the canal incision is carried out with a No. 15 blade, remaining a few millimeters deeper than the entrance of the bony external canal.
DAIGRAM
Meatal skin flap The meatal skin is elevated form the bone by means of a “universal” microdissector. The elevation of skin is carried out under direct vision until the posterosuperior margin of the drum and the anteroinferior overhang of canal bone are exposed. 5
Preservation of the anterior tympanomeatal angle The tympanic annulus should never be elevated between 2 o’clock and 4 o’ clock on the right side (8-10 o’clock on the left side) because an intact anterior tympanomeatal angle is essential for optimal functional end results. Violation of the anterior “sacred” attachment of the annulus induces blunting of the tympanomeatal angle and lateralization of the drum. This reduces the vibratory properties of the drum. Elevation of the tympanoemeatal flap The tympanomeatal flap is elevated posteriorly Baring the malleus tip The tympanic membrane is elevated form the tip of the malleus to avoid burying epidermal rests under it. Harvesting and preparation of the temporalis fascia Exposing the temporalis muscle. An incision is made through the fascia 5 mm above the caudal edge of the muscle. The fascia is then separated from the underlying muscle using the flat handle of the knife. The desired quanitity of fascia is cut out with a pair of curved fascia scissors. The graft is then placed over a glass board, and the excess fat and muscle tissue are removed with a No. 20 bladed. An incision is made with the knife according to the expected position of the malleus handle.
DAIGRAM
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Fixation of the underlaid graft The fascia is kept moist to avoid killing the fibrocytes, and therefore speed up revascularization and healing. The fresh graft is introduced under the anterior margin of the perforation. Support is provided by the tynmpanic sulcus and by the bare tip of the malleus handle. Repositioning the tympanomeatal flaps Tympanomeatal flaps are repositioned, keeping the fascia locked on the tympanic sulcus. Repositioning the meatal skin flap Gelfoam soaked in Otosporin is used to keep the tympanomeatal flaps and the meatal skin in place. Reepithelization of the anterosuperior canal wall requires 3 to 4 weeks.
DAIGRAM
►Complications of Myringoplastry ►Underlay Grafting ►Anterior reperforation 7
Anterior tympanomeatal cholesteatoma Blunting the anterior tympanomeatal angle This complication occurs if the anterior tympanic annulus has been separated from the sulcus. Overlay Grafting Leateral displacement of the graft Inclusion or residual cholesteatoma Inclusion cholesteatoma is a typical complication of overlaid grafting when the deepithelization of the lateral surface of the drum has not been complete. Residual cholesteatoma occurs when remnants of epidermis have been left inside the middle ear cavity. This complication can also occur after underlay grafting. ►Cholesteatoma pearls ►Retraction pocket Special Applications with Tympanoplasty Transcanal Myringotomy with ventilating Tube Transcanal myringotomy with ventilating tube (Grommet) is used when chronic serous otitis media is accompanied by a conductive hearing loss of 30 dB or more. Surgical Technique This procedure is performed under general anesthesia for children and local anesthesia for adults. The ear speculum is introduced and kept in place with the left hand. Myringotomy The myringotomy is performed with a myringotomy knife in the anteroinferior quadrant of the drum. A radial incision is preferred to a circumferential to avoid infolding of the incision’s margins and subsequent 8
Formation of cholesteatoma. The length of the incision should match the diameter of the inner flange of the Grommet. The incision should avoid the tympanic annulus to prevent early extrusion. In the presence of a retracted drum, the myringotomy should be made within the deepest available space in the hypotympanum. Transportation of ventilation tube The ear speculum is kept in position with the left hand, and the ventilating tube is introduced into the external auditory canal with the right hand.
DAIGRAM
Ventilating tube on the tympanic membrane The tube is placed on the tympanic membrane close to the myringotomy opening.
DAIGRAM
9
Introduction of ventilating tube The 1.5 mm, 45o hook I s used to place the inner flange of the tube over the myringotmy incision. Introduction of ventilating tube The inner flange of the tube is rotated into the tympanic cavity using the 1.5 mm, 45o hook. Surgical treatment of Acquired Cholesteatoma Aims - Eradication of disease - Prevention of recurrent and retention chloesteatoas - Formation of a dry and self-cleansing cavity - Restoration of tympanic aeration - Reconsturction of a sound-transformer mechanism Closed (intact canal wall) Tympanomasoidectomy The principle of the intact canal wall tympanomastoidectomy is completely remove the cholesteatoma matrix without disturbing the anatomy of the external bony canal. The combined transcanal and transmastoid approach permits removal of cholesteatoma invading the facial recess. Cholesteatoma in the sinus tympani may be difficult to extirpate because of the limited visibility in the area. Open canal (wall down) The principle of an open tympanomastoidectomy is to create a large cavity in which no retention of keratinizing epithelium is possible. 10
Choice of Approach The choice between open and closed tympanomastoidectomy depends on: - Fundction of the Eustachian tube - Extent of the disease The pneumatization of the temporal bone is a good measure of the function of the Eustachian tube. A sclerotic mastoid is generally the result of poor Eustachian tube function during childhood. The criteria for the choice of the approach in mastoid surgery are: 1. Limited disease with good pneumatization: close cavity 2. Sclerotic mastoid with extensive disease: open cavity 3. Disease, particularly cholesteatoma matrix, cannot be radically removed beyond doubt: open cavity. Closed Mastoido-Epitympanectomy Surgical Technique A closed MET includes mastoidectomy, epitympanectomy, posterior tympanotomy, and tympanoplasty. Surgical Steps - Retroauricular skin incision - Raising of periosteal flap - Canal incisions - Exposure of external auditory canal and mastoid - Elevation of metal skin flap 11
Middle ear inspection The tympanomeatal flap is raised and the extent of cholesteatoma invasion of the middle ear assessed. The decision to perform a closed cavity is made on the basis of (1) no evidence of Eustachian tube dysfunction, (2) good pneumatization of the tymanomastoid cleft, and (3) limited extension of cholesteatoma Mastoidectomy: exposure of mastoid plane The mastoid plane is exposed with two articulated retractors supplemented by a third rigid retractor placed between the temporalis muscle and mastoid tip. Mastoidectoy: identification of antrum: The antrum is identified at the intersection of two grooves formed by removing bone along the superior and posterior canal wall. The entrance of the bony external canal should not be lowered when drilled for the antrum. The middle fossa dura and sigmoid sinus are skeletonized at this stage when working in a sclerotic mastoid. Epitmpanectomy: exposure of the attic: The lateral wall of the attic is removed with a diamond burr. The cholesteatoma fills the epitympanum. The matrix is opened with small tympanoplasty scissors, and the contents of the cholesteatoma sac are evacuated by suction. The size of the cholesteatoma is reduced to allow easier separation of the matrix form the surrounding bone.
12
Epitymanectomy: identification of tympanic facial nerve: The atrophic incus is removed. The chloesteatoma matrix is elevated from the lateral semicircular canal. The tympanic facial nerve is identified along the inferior margin of the lateral semicircular canal. Management of semicircular canal fistula Always expect a fistula when elevating the cholesteatoma matrix from the lateral semicircular canal. Look for a fistula before removing the medial wall of the cholesteatoma sac. In the presence of a fistula, leave the covering skin until the end of the operation to avoid damaging the inner ear. Remove the skin over the fistula when the bone work and the removal of the remaining matrix is completed. Use constant irrigation. The matrix covering the fistula is only removed if the endostium is intact. This is usually possible in fistulas up to 2 mm in diameter. If the perilymphatic space is open, the skin covering the fistula is replaced in its original position. If the matrix has been removed, the intact endostium of the fistula is covered with bone dust (obtained by drilling) mixed with fibrin glue (bone paste). The fistula is finally covered with fresh temporal is fascia placed over the bone paste. Epitympanectomy exenteration of the attic The malleus neck is divided and the head of the malleus removed. The cholesteatoma matrix is carefully detached form the walls of the epitympanum, and the size of the cholesteatoma sac is successively reduced by cutting away excess matrix.
13
The matrix lying lateral to the tympanic segment of the facial nerve is removed form the supralabyrinthine and supratubal recess. The position of the geniculum, petrosal nerve, and labyrinthine segment of the facial nerve should be known to avoid injury of a dehiscent nerve. Posterior tympanotomy The bone situated between the pyramidal facial nerve and the chordatympani is drilled away along the tympanic segment of the fallopian canal. The resulting opening to the middle ear is the posterior tympanotomy. The size of the tympanotomy depends on the extent of the cholesteatoma in the facial recess and sinus tympani. A wide exposure of the sinus tympani requires sacrifice of the chorda. If the cholesteatoma is limited to the superior half of the oval window niche (above the stapes arch), complete removal of the matrix can be accomplished at this stage, working form both sides of the intact canal wall (combined approach). Matrix covering the steps and oval window is removed after completion of all bone work because uncontrolled suction irrigation might damage the exposed inner ear. Removal of matrix from the stapes is performed in a posteroanterior direction, taking advantage of the stability offered by the stapedial tendon. Tympanopasty Primary reconstruction of the ossicular chain is possible in this case because the stapes, the malleus handle the tensor tympani tendon, and the pars tensa of the tympanic membrane are intact. Incus is interposed between the stapes head and malleus handle. 14
Pacing and transmastoid drain Packing and transmastoid drain mastoidoepitympanectomy with tympanoplasty.
in
closed
Open Matoido-Epitympanectomy with Tympanoplasty Surgical steps Retroauricular skin incision The retroauricular skin incision is carried out along the hairline and extends inferiorly over the mastoid tip into a crease of the skin. The skin incision must be posterior enough to avoid lying over the exenterated mastoid bone. Exposure of the mastoid The soft tissues are elevated over the mastoid. The periosteum covering the mastoid is incised from the posterior edge of the temporalis muscle to the mastoid tip. Two small anterior incisions are performed along the superior and inferior edge of the external canal. Exposure of the external auditory canal The posterior wall of the external auditory canal is incised (AB) with a No.15 blade remaining a few millimeters deeper than Henle’s spine. Exposure of external auditory canal The external canal incision is extended interiorly to 2 O’ clock. A Key raspatory is used to elevate the canal skin exposing the root of the zygoma.
15
Exposure of external auditory canals Two articulated retroauricular retractors are introduced, exposing the external canal. Meatal skin flap The lateral canal skin is elevated under direct vision to the tympanic sulcus. Bleeding during elevation of the meatal skin flap is greatly reduced by infiltrating the canal skin with local anesthesia at the time of the retroauricular skin incision. Exploration of the middle ear Postrerosuperior tympanomeatal flap is elevated to assess the intratympanic extent of cholesteatoma invasion and the condition of the ossicular chain. In the presented case, the cholesteatoma covers the oval window niche above the chorda tympani and has eroded the long process of the incus. Antrotomy (atticotomy): Two grooves are drilled the superior and posterior canal walls. The antrum is located at the intersection of both grooves. Antrotomy The cholesteastoma fills the antrum. The lateral wall of the drilled away (epitympanotomy). The decision to perform an open cavity is made on the basis of 1. History of poor Eustachi tube function 2. Reduced pneumatization of the mastoid, and 3. Extend of cholesteatoma invasion.
16
Mastoidectomy: wide removal of lateral bone A wide removal of bone is carried out from the zygomatic arch to the middle fossa dura, the sinodural angle, the sigmoid sinus and the digastrics muscle. Exposure of the tympanic facial nerve The tympanic fallopian canal is identified at the inferior edge of the lateral semicircular canal. Lowering the facial ridge: Lowering the facial ridge is performed with diamond burrs and suction-irrigation from both ends, the tympanic segment of the facial nerve, and the stylomastoid foramen. The bone is removed until the nerve becomes visible under the last eggshell of bone. The level of the mastoid segment of the fallopian canal is determined by a line drawn form the tympanic facial nerve to the stylomastoid foramen. A further landmark for the mastoid facial nerve is the inferior edge of the posterior semicircular canal. The pyramidal segment of the facial nerve is situated 2 mm anteriorly and laterally to the inferior edge of the posterior semi circular canal. Exenteration and exteriorization of the retrofacial cells. The retrofacial cells ae completely removed, keeping the skeletonized facial nerve in view. The rotation of the burr is away from the facial nerve. Complete exenteration of the retrofacial cells may require exposure of the blue area of the jugular bulb medial to the mastoid segment of the fallopian canal. 17
Epitympanectomy The cholesteatoma matrix is elevated form the supralabyrinthine and supatubal recesses, remaining lateral to the tympanic segment o f the facial nerve. Removal o cholesteatoma from oval window The cholesteatoma matrix covering the oval window niche is removed after completion of the bone work to aoid the risk of prolonged exposure of the inner ear. Repair of aperilymphatic fistula is dangerous if it is followed by major bone work involving continuous suction-irrigation. Tympanoplasty in Open Mastoido-Epitympanectomy Tympanoplasty in an open cavity varies depending on the amount of residual tympanic membrane. Underlay grafting is used in the presence of an anterior remnant of the drum. Overlay grafting is the teachnique of choice when no anterior tympanic membrane remnant is present. Packing of open cavity The exteriorized cavity is filled with Gelfoam soaked in Otosporin. Meatoplasty The meatoplasty is necessary for the correct exsteriorization and self-cleansing property of an open cavity. The is the meatoplasty is made as large as required by the shape of the bony cavity. Granulation tissue and the myo-subcutaneous flap will provide a natural reduction in the size of the cavity entrance. Failure to perform meatoplasty in an open cavity will lead to a chronic secretion and to retention cholesteatoma because of inadequate exteriorization. 18
Chonchal incision The concha is incised with a No. 11 blade. The incision goes through the skin and cartilage and is directed poster superiorly toward the sinodural angle. Removal of conchal cartilage Sufficient cartilage is removed on each side of the incision to allow introducation of the tip of the little finger into the open cavity. Note that the root of the anthelix is included in the resection to allow sufficient superior exteriorization of the cavity. Elevation of skin from conchal cartilage Curved tympanoplasty scissors are used to elevate the skin from the conchal cartilage. Exposure of conchal cartilage The mobilized skin is elevated with skin hooks, exposing the cartilage. Meatal entrance after excision of conchal cartilage View of the meatal entrance after removal of the conchal cartilage with tympanoplasty scissors. Inwards rotation of conchal skin flaps The auricle is rotated anteriorly, and the soft tissues medial to the conchal cartilage ae mobilized with tympanoplasty scissors. Further resection is necessary if the skin flaps do not cover the edge of the remaining conchal cartilage. A free edge of cartilage may lead to perichondritis. 19
Lateral fixation of conchal skin flaps The conchal skin flaps are anchored with 2-0 catgut sutures to the temporalis muscle (superiorly) and the mastoid soft tissues (inferiorly). The knots of the sutures are left loose and tightened only after posterior replacement of the pinna. Completed meatoplasty The anchoring sutures of the conchal skin have been tightened. The dfGelffoam packing (anterorly) and the occipital. Wound closure and packing The retroauricular wound is closed in tow layers using 2-0 catgut and 3- Ethiconsutures. Gauze impregnated with Terracortril ointment is introduced over the Gelfoam. Stepedotomy Surgical Technique The surgical steps of stapedotomy are demonstrated for otosclerosis since this condition is the most common indication for the procedure. The stapedotomy opening as well as the introduction and fixation of the TPP, is done before division of the incudostapedial joint and before removal of the stapes arch. Endaural skin incision A helicotragal skin incision is carried out using a No. 15 blade while enlarging the external canal with a nasal speculum. 20
Widening of external auditory canal An endaural raspatory is used to separate the soft tissues form the underlying bone at the superior edge of the external auditory canal. Widening of external auditory canal s Two endaural retractors are placed perpendicular to each other over the entrance of the exsternal auditory canal to give the necessary exposure. Tympanometal flap The triangular tympanomeatal flap has a posterior limb that begins at 8 o’ clock, ascending spirally from the tympanic annulus to the lateral edge of the external auditory canal. The anterior limb of the tympanomeatal incision descends from the lateral opening of the exdternal canal along the tympanosquamous suture towards the lateral process of the malleus. The intrameatal incisions are carried out with a rounded scalpel handle, carrying a No. 11 balde. Tympanomeatal falp The tympanomeatal flap is eleated form the underlying bone with the universal microraspatory. The most important landmark in this step is the posterior tympanic spine (posterior end of the incisura tympanica Rivini). Tympanomeatal flap After exposure of the posterior tympanic spine, the anterior limb of the tympanomeatal incision is extended with tympanoplasty microscissors towards the anterior spine remaining above the short process of the malleus. 21
Tympanomeatal flap The elevation of tympanic annulus form the tympanic sulcus begins at the posterior tympanic spine, using a universal microrespatory. a.
The chorda tympani is left attached to the retracted drum. The pars flaccida of the tympanic membrane is elevated with the universal microraspatory over neck and short process of the malleus. A cartilaginous apophysis may be found over the lateral process of the malleus. This cartilage is elevated with the tympanomeatal flap. Exposure of the short process of the malleus keeps the tympanomeatal flap away and allows early determination of the mobility of this ossicle. Gelfoam soaked in 1% Lidocaine solution is placed in the exposed middle ear cavity for 2 minutes if pain is experienced by the patient while the tympanomeatal flap is being elevated.
Canalplasty The large end of a curette (a) or a diamond burr (b) is used to enlarge the external canal until the lateral process of the malleus becomes visible. Exposure of the oval window After elevation of the tympanomeatal flap, the bone coering the oval window niche is removed with the small end of a sharp curette. Care is taken to avoid trauma to the chorda tympani. Exposure of the oval window The rotational movements of the sharp curette are directed from medial to lateral when exposing the oval window. Bone fragments should 22
be continuously removed to avoid inadvertent luxation of the incus by pushing them medially with the curette. Exposure of the oval windows The correct exposure of the oval window is obtained when the short process of the malleus, the tympanic segment of the facial nerve, and the pyramidal process are visible. Visualization of these three landmarks is essential for correct execution of the further steps of surgery. Mobilization of the chorda tympani At times the chorda tympani runs within the bony posterior canal wall, preventing correct exposure of the oval window. If this is the case, the bone covering the chorda has to be removed using the small end of a sharp curette or with the universal microraspatory. The chorda tympani should be preserved whenever possible. However, if mobilization is impossible without lesion, the chorda is cut with tympanoplasty microscissors. Determination of prosthesis length A malleable measuring rod is used to determine the distance between the footplate and the lateral surface of the incus (average length 4.7mm); 0.5 mm are added to account for the protrusion of the prosthesis into the vestibule. The average total length of the prosthesis is, therefore 5.2mm. Manipulations of the mucosa of the oval window may cause pain. In this case, a Gelfoam pledget soaked in 1% Lidocaine is placed in the oval window for 2 minutes. 23
Trimming the prosthesis A special cutting block has been developed so that only one size prosthesis, a Teflon platinum band piston (TPP), 7mm long, 0.4mm diameter, is stocked. The prosthesis is trimmed on the cutting block. The prosthesis is placed on a groove of the cutting block and advanced with watchmaker forceps through the perforated bridge until the desired length is reached. The excess of the Teflon piston is cut away using a No. 11 blade. Storage of prosthesis The trimmed prosthesis is grasped with watchmaker forceps and placed in the 0.4mm hole of the cutting block for later use. Safe area for stapedotomy The saccule and utricle are more than 1 mm below the inferior central two thirds of the stapes footplate. This is therefore, the safest place for the stapedotomy opening. Perforation of the footplate A set of four manual peforators (0.3-0.4, 0.5, and 0.6 mm diameter) is used to make the stapedotomy opening in the footplate. The perforators are rotated back and forth between the thumb and index finger of the right hand. The tip of each perforator is only partially introduced into the vestibule. This is was the 0.6 mm diameter perforator produces an opening that is only slightly larger than 0.4mm. the pressure applied to the perforator tip is minimal. The actual work is carried out with the perforator’s shoulder.
24
Perforation of the foot plate The correct size of the stapedotomy opening is confirmed with a malleable 0.4mm measuring caliper. The stapedotomy opening should allow free movement of the tip of the caliper rod. An opening that is too narrow will hamper the proper fre movements of the piston, which may lie at an oblique angle to the footplate. Introduction of the prosthesis The TPP is picked up from the cutting block with a large alligator forceps. The cutting blick is held such that the alligator forceps is guided by the left thumb. Picking up the prosthesis at the proper angle is essential for correct placement. Introduction of the prosthesis The TPP is first placed over the stapes footplate. The length is correct if the loop of the prosthesis lies 0.5 mm lateral to the incus. A prosthesis that is too long is replaced on the cutting for further trimming. A prosthesis that is too short is discarded and substituted with a new one. Introduction of the prosthesis After confirmation of its correct size, the prosthesis is moved over the stapedotomy opening and advanced into the vestibule with a 0.5 mm, 45o hook. Fixation of prosthesis to incus The prosthesis loop is crimped over the incus with a large alligator forceps. This step is performed while the incudostapedial joint is still intact. The intact incudostapedial joint is the best guarantee against undue mobilization or fracture of the footplate. 25
Removal of stapes arch The incudostapedial joint is separated with a joint knife. The mobility of the malleus and incus may be fully appreciated only after this step. Removal of stapes arch The stapedial tendon is cut with tympanoplasty microscissors. Removal of stapes arch The posterior crus is cut with left crurotomy scissors. Right crurotomy scissors are used for the left ear. Exposure of the pyramidal process is necessary to provide sufficient space for the crurotomy. Removal of stapes arch a.
The anterior crus is crushed at the level of the footplate with a 2.5mm, 45o hook introduced between the incus and malleus handle.
b.
A downward rotational movement is performed when the tip of the hook has reached the base of the anterior curs. In this way, the crus is crushed with a hook against the anterior wall of the oval window niche. The patient is warned not to react to the sudden noise and possible pain resulting form this surgical step.
c.
If correctly broken, the stapes arch has a long anterior and a short posterior curs. Bleeding occurring form the mucosa of the promontory has no adverse effects since the prosthesis is already in situ.
26
Checking final mobility of ossicular chain After removal of the stapes arch, the correct mobility of the ossicular chain is tested with a 1.5-mm, 45o hook. There should be no free movement of the prosthesis loop when the incus is moved. Sealing of stapedotomy opening a.
Connective tissue form the endaural incision is used to seal the stapedotomy opening. Usually, three tissue pledgets are obtained with large tympanoplasty microscissors.
b.
Tissue pledgets are placed around the stapedotomy opening using a 1.5-mm, 45o hook and a 0.2-mm footplate elevator.
Sealing of stapedotomy opening a. Blood is necessary for seling the fenestrated footplate. Therefore, venous blood is removed at the beginning of the operation form the cubital vein of the patient. The venous blood is stored in a syringe and introduced at this stage of surgery over the connective tissure covering the stapedotomy opening. b. A drop of fibrin glue is then applied to complete the seal. Repositioning the tympanomeatal flap The tympanomeatal flap is repositioned with a microsuction tube. Repositioning the tympanomeatal flap The bone defect resulting from curetting the canal wall is completely covered by the repositioned tympanomeatal flap. 27
Packing and wound closure a.
Gelfoam pledgets soaked in Otosporin are used to keep the tympanomeatal flap in place.
b.
Note that the Gelfoam is smaller than the diameter of the exsternal canal to avoid excessive pressure on the tympanic membrane after swelling.
Packing and wound closure The endaural incision is closed with two 4-0 Ethibond sutures. A strip of gauze impregnated with Terracortril ointment is introduced into the lateral external canal. The packing is left in place for 2 to 4 days. Complications:1. Sensory Neural Deafness 2. Facial Nerve Paralysis 3. Vertigo 4. Tinnitus 5. Perilabrinthine Fistula
27
THE MICROSCOPE The operating microscope must be used routinely in all ear operations. The purpose of the microscope is to magnify the operating field and provide sufficient illumination when working at the deeper parts of middle ear or inner ear. PARTS OF THE MICROSCOPE:Basically the operating microscope consists of three parts. Viz. (a)
Optical system or optics;
(b)
Lighting or illumination;
(c)
Stand.
Perfect optics and good illumination are the basic requisistes for the microscope. Optical System:It consists of three parts which controls the distance between lens and object and magnification. The parts are: (a) (b) (c)
Binocular assembly; Magnifiation changer; and Objective lens.
Binocular assembly: The eye pieces are fitted in ocular tubes. There are various eye pieces available with the following magnifications. 10x – 12.5x -16x -20x 20x eye pieces gives maximum magnification but the field of vision is small. 29
Generally 12.5X lenses are used. These eye pieces have a dioptre scale of -5 to +5 and this can be adjusted according to the refractive error of the dissector. Magnification changer: The knobs are arranged at the side of the head of the microscope. The magnification varies form 6 to 40. For routine ear work 10 magnification is used. For finer work 16 magnification is used. As the magnification becomes higher the field of vision is smaller and the depth of the field decreases rapidly. Objective lens: The focal length of a lens is the distance between the object and the lens. The objective lens is fitted at the bottom of the head. It can be easily screwed and unscrewed. For ear surgery 200 mm focal length lens is used. For nose and paranasal sinuses surgery 300 mm lens is used. For laryngeal surgery 400 mm focal length lens is used. Illumination: Adequate illumination is necessary for good microscopic work. But lighting should not be too bright; otherwise it will give glaring effect of the operating field. Sources of illumination are: 1. Halogen lamp; and 2. Fibro optic light source. 30
Stand: The microscope should run easily on the stand and the microscope can be fixed on the stand tightly with knobs provided. The arms and their control knobs are so arranged on the stand that the head of the microscope can be tilted in any direction at any level convenient to the operator. DO’S AD DO’T’S DO’S 1. Always cover the microscope when not in usage to protect against dust. 2. When the operation is over, clean the lens with an air blowing brush. 3. After the operation remove the objective lens from microscope and wipe of any blood stains and clean it properly. 4. After the operation all the knobs are tightened properly. 5. To prevent fungus formation in the lens (1) Switch on the light for half an hour daily (2) Place a bag of silica gel near the lens system to absorb moisture. DO’T’S 1. Don’t leave the microscope uncovered when not in use 2. Don’t clean the lens with a hard cloth. 3. Don’t allow the water to spill inside the microscope. 4. Don’t turn the lights on and off frequently. 5. Don’t leave the microscope unused for long periods of time. This system consists of three parts. 1. Motor 2. Hand pieces 3. Burrs 31
Motors: These are available in the form of ► Hanging type ► Stand type ► Table top type These motors usually work with 12000 to 20,000 rpm. Micro motors: Which are the latest in this field are small and handy and work with 30,000 to 40,000 rpm. Hand Pieces: Two types are available One is straight and the other is contrangular. Burrs There are three varities. 1. 2. 3.
Cutting Polishing; Diamond.
Each variety is available in various sizes from 1 mm to 10 mm sizes. Cutting burrs are used for most of the bone work. With cutting burrs bone work will be faster. Polishing burrs are used at the end of operation for smoothening the cavity. Diamond burrs are used near the facial nerve, dura and sinus. Whatever type of burr is used in whatever speed, heat is produced and this may cause damage to the facial nerve, or inner ear. Also, bone dust will be produced during drilling. To prevent heating and clogging 32
Constant irrigation with suitable fluid and suction is essential. In live operations Ringer lactate is used. Burrs and hand pieces are sterilized by formalin vapour. The handpieces and burrs should be cleaned thoroughly well and lubricated with 3 in 1 oil.
33
Self assessment 1. 2. 3. 4. 5. 6.
What is tympanoptaty? How many types of surgical approach used in myringoplasty? Mention Indication of stapidotomy What are the post operative complication after stapidotomy? What is AIM of tympanoplasty? In which quaduant of tympanic membrane. Ventilating tube is inserted? 7. What is canal wall down tympano mastoril surgery? 8. What is complication of over lay grafting? 9. What is posterior tympanotomy? 10. What is facial ridge & Bridge?
THE LARYX The complete investigation of laryngeal disease may necessitate
examination
by
external
palapation,
indirect,
laryngoscopy, direct laryngoscopy, stroboscopy and radiography and biopsies and swabs may be taken. Indirect laryngoscopy The cooperation and relaxation of the patient are essential to the success of an examination, and before he begins the examiner should explain what he is going to do and how he would like the patient to help. The patient’s to help. The patient’s position is important: he should sit with his body upright and his head level: the examiner sits facing him and draws the head a little forward from the shoulders. Any dentures the patient may be wearing are removed, and the largest mirror which will conveniently fit at the back of the patient’s throat is selected; a small mirror gives a less complete view of the larynx and pharynx and may slip behind the soft palate when the mirror is raised to elevate it. The mirror is warmed by holding it, face downwards, in the flame of a spirit lamp and before it is introduced into the patient’s mouth; its temperature is tested on the examiner’s hand or cheek. The patient is asked to put out his tongue and covering it with the gauze square, the examiner takes hold of it with the thumb and middle finger of his left hand; the forefinger lifts the upper lip out of the way, and rests on the incisor teeth for steadiness
1
At this point the patient is asked to breathe steadily in and out through his mouth in order to separate the tongue and soft palate; otherwise the mirror cannot be placed in position. The warmed mirror, held in the right hand like a pen, is passed face-downwards over the tongue (with care not a touch the tongue and smear the surface with saliva) and placed firmly against the base of the uvula, lifting it upwards and backwards; the shaft rests against the angle of the mouth for support. The examiner focuses his light on the mirror and, by tilting the mirror in different directions, the reflected images of the various structures of the larynx and laryngopharynx may be seen. The tongue should be held firmly imposition, but not dragged upon or pinched. Too much downward pull will press the lower surface of the tongue against the lower incisor teeth, causing pain, or even laceration of the frenum. There are many patients who retch or gag when the mirror is put in to position and in these cases the soft palate must be anaesthetized by spraying with a four per cent lignocaine aerosol, or by the patient sucking an amethocaine orlignocaine lozenge. Structures visible on indirect laryngoscopy The first structures seen are the anterior surface of the epiglottis, the base of the tongue and the valleculae. Raising the mirror and tilting it downwards brings into sight the entrance to the larynx. It is bounded in
2
front by the upper edge of the epiglottis, behind by the mucous membrane between the arytenoids cartilages, and on each side by the aryepiglottic folds. The epiglottis is a flattened, leaf-like structure, covered with pale mucous membrane, across which a few blood vessel arvorize. It is more folded upon itself in infants and young children than in adults. It may overhang the larynx, making it almost impossible to get a good view of the interior. The posterior surface of the epiglottis forms a slight elevation, known as the tubercle, just above the anterior commissure of the vocal cords. Running postero-medially form the lateral margins of the epiglottis to the arytenoids cartilages on each side is a free form the lateral margins of the epiglottis to the arytenoids cartilages on each side is a free fold of mucous membrane. This is the aryepiglottic fold it is thin in front, but thickens behind, where it contains the cartilages of Wrisberg and Santorini. Beneath these are the eminences formed by the arytenoids cartilages, and in between is the interarytenoid space. The ventricular bands lie immediately above the vocal cords and appear to be in contact with them: the ventricles of the larynx cannot usually be seen by indirect laryngoscopy. The vocal cords run backwards from the angle of the thyroid cartilage to the vocal processes of the arytenoids, forming the triangular aperture of the rima glottids. In the mirror-image the vocal cords appear as flat, ribbon-like structures with sharp, free margins. They are glistening white in colour and there should
3
Not be any vessels visible on their surface. The motility of the cords should be observed during quiet respiration and by making the patients phonate, saying ‘e-e-e-e’. If there is no paresis or fixation, the cords and arytenoids will approximate and the interarytenoid space will be obliterated. Below the vocal cords is the subglottic space the walk of which are hidden form views out, The first two or three rings o the trachea may be seen anteriorly. The larynx line in contact with the posterior wall of the pharynx, and moves away from it only on deglutition; thus the lower half of the hypopharynx cannot be seen. The entrances to the pyriform fossae can be seen in the mirror and a little more of he fossae becomes visible on phonation, but complete inspection is not possible by the indirect method of examination. The image of the larynx seen in the mirror is reversed anteroposteiorly but not from side to side. The anterior commissure will appear to point away from the examiner and the right-hand structures will be seen on his left. The most difficult part to bring into view is the anterior commissure, and the larynx cannot be passed as normal until this has been inspected. It is often invisible during quiet respiration, but if the patient is asked to say ‘e-e-e-e’ the larynx elevates and the epiglottis tilts
4
Forwards, uncovering the anterior commissure. In some cases the overhang of the epiglottis may be so marked that this maneuver fails. Another obstacle to satisfactory examination is the fact that the tongue may elevate on phonation and hide the mirror just when a view is most wanted; this can be overcome by using a tongue depressor, or by drawing the tongue well across to one side of the mouth while viewing the mirror in a line between the lateral border of the tongue and the anterior faucial pillar. Children are difficult to examine by indirect laryngoscopy and direct inspection is usually required if it is necessary to see the larynx. Sometimes however, a sufficiently good view can be obtained if the mirror is placed almost horizontally against the hard palate, instead of the uvula, so that the cough reflex is not elicited. Observations during examination: During examination the observer must look for, and assess the significance of any abnormal appearances. There may be injection, swelling, oedema, proliferation or ulceration; and the movements of the vocal cords may be impaired. Impairment of movement of a vocal cord may be due to a hidden subglottic growth, and forthy saliva in the pyriform fossae may be traced to a low laryngopharyngeal or upperoesophageal carcinoma.
5
Observation of the cartilage of Wsisberg in the aryepiglottic fold may be of assistance in the diagnosis of laryngeal paralysis, especially in differentiating paralysis from fixation of the cricoarytenoid joint. In the latter case, the cartilage retains its normal upright position, braced by the action of the posterior cricoarytenoid muscle. In recurrent laryngeal nerve paralysis this action fails. And the cartilage droops forward over the posterior end of the vocal cord, making it appear shorter than its fellow. Indirect laryngoscopy is used mainly for diagnosis. The laryngeal mirror is also useful in guiding the manipulations for anaesthetizing the larynx and trachea for direct laryngoscopy and bronchoscopy, and when bronchograms are required iodized oil may be introduced into the trachea via the larynx. Direct laryngoscopy By this method the larynx is looked at directly through a rigid endoscope. Except for injuries and diseases of the cervical spine. When there is marked laryngeal obstruction, preliminary tracheostomy may be necessary. The design of larynogoscopes has evolved from Chevalier Jackson’s through Negus’ and Kleinsasser’s, with many variations and modifications. Modern instruments employ the proximal lighting of Negus.
6
Anaesthesia General anaesthesia For children from two to seven years old trimprazine tartrate is an excellent premeditation. It is given by mouth 1 ½ hours before operation at a dose rate of 3-4 mg/kg. An intramuscular injection of 0.4-0.6 mg of atropine is also given half an hour before the operation is due to begin. Above the age of seven years pethidine and atropine are probably preferable to Omnopon and scopolamine because they do not depress the cough reflex so much Pethidine 10 mg/ 6.35 kg for children and a full dose of 100mg for adults it given with 0.6 mg of atropine 45 min preoperatively by intramuscular injection. The introduction of the muscle relaxant drugs has been of great help in per-oral endoscopy. Adults are induced with intravenous thiopentone followed by intravenous suxamethonium and when relaxation has been obtained a small-bore (7mm) endotracheal tube is passed through the nose or the mouth. Anaesthesia is maintaine through the tube with nitrous oxide oxygen and halothane. The tube lies in the posterior commissure and most of the larynx can be thoroughly inspected while it is in position. It is removed or displaced by the laryngoscope to allow inspection of the posterior commissure and adjacent regions.
7
Instruments ‘Wide-mouthed’ laryngoscopes modified Kleinsasser types in a range of sizes are ideal for micro-laryngoscopy. In cases of difficult due to anatomical problems of prominent teeth large tongue, shor narrow-angled mandible, or stiff cervical spine, the Negus tubes with their smaller diameter are necessary to allow insertion through the easier angle offered laterally between the molar teeth. Negus standard and anterior commissure larynoscopes, with oesophageal speculum, and grasping forceps, suction tubes and swab-carriers fibre-optic light carriers. Instrument used in direct laryngoscopy (a) Aspirating tube, Chevalier Jackson open end: (b) swab holder, Coolidge; (c) nodule forceps Chevalier Jackson; (d) grasping forceps, chevalier Jackson; (e) biopsy forceps, (f) cutting forceps Basic instruments for micro-laryngoscopy; 1. 2. 3. 4. 5. 6.
Diathermy electrode Angled cupped forceps Straight cupped forceps Fine serrated grasping forceps Scissors Sickle knife
The formalin sterilizing cabinet
8
Non-sterile equipment must include a fibre-optic light source, powerful suction pump and binocular operating microscope fitted with a long-focus (400mm) objective lens. Position of the patient
Diagram
The anaesthetized relaxed patient lies supine with an ordinary pillow under the occiput. The head-flap of the table is included in the sterile head-drape so that the surgeon can himself adjust its elevation without becoming unsterile.
9
A strong metal bridge is positioned for the Loewy support before draping is completed. Examination Examination should be conducted with full aseptic precautions to prevent the carrying of infection form one patient to another. Care must be taken to protect the teeth lips, and tongue form Insertion of a plastic guard to protect the upper teeth. Fingers of right hand protecting lips while beak of laryngoscope slips backwards a little to the right side of the midline of the tongue. The laryngoscope is now behind the epiglottis, which is being lifted forwards to establish the final definitive view required. Pressure and laceration at every stage. Generous lubrication and unhurried, gentle work are required. An excellent dental guard. When the posterior one-third of the tongue is reached, the laryngoscope is directed to the then guided behind the epiglottis advanced about 1 cm and elevated. This is effected by lifting upwards and forwards with the left hand. There must be no levering of the laryngoscope on the upper teeth or gums. Only the posterior part of the larynx is usually seen at first, and further elevation may be necessary to being the anterior commissure into view. At this stage the Loewy support can be fitted and judicious use of the extension screw will give a better view of the anterior half of the larynx.
10
Sometimes it is useful to get an assistant to press the thyroid cartilage back from the outside. The possibility, of chipping of an incisor, or even dislodgment of a loose tooth. If a lesion is in the posterior part of the larynx the laryngoscope must be placed behind the anaesthetic tube, lifting it forwards. When the required exposure of the larynx is finally achieved and stabilized the operating microscope is bought into position. Micro-laryngoscopy. (a) Ventricular cyst; (b) carcinoma of vocal cord The standard laryngoscope gives a general view of the larynx, but the anterior commissure laryngoscope is more useful for a detailed examination and for exposing the anterior commissure of the larynx. The tip of the anterior commissure laryngoscope can be sued to lift up the ventricular bands, so that the interior of the ventricle is exposed and it can be passed between the vocal cords to inspect the subglottic region. Chronic hyperplastic laryngitis Pathology The healthy larynx, is not lined everywhere with respiratory (i.e. ciliated columnar) epithelium. The free part of the epiglottis the aryepiglottic folds and the vocal cords are covered with nonkeratinized squamous opithelium. So far as the vocal cords are concerned the junction of the respiratory with the squamous epithelium is clear-cut 11
where the upper surfaces join the floor of the ventricles as the superior arcuate lines but beneath the glottis, the border on either side, the inferior arcuate line, is into so clear. In health, squamous epithelium will not be found over the false cords, the petiolus of the epiglottis or in the laryngeal ventricles, nor is keratinzation of the squamous epithelium ever observed. The ciliated epithelium on the false cords and on the lower part of the epiglottis becomes liable to metaplasia into squamous epithelium, and the squmaous epithelium of the cords and, less commonly the metaplastic epithelium, may become kertatinized to a greater or lesser extent. This assumption by the laryngeal epithelium of a skin-like character has been called epidermization. The changes are first seen in the vocal cords which become hyperaemic and swollen. The swelling is smooth initially but soon becomes irregular, granular or nodular. The earliest appearance of keratinization, usually seen again in the true cords, has been likened to forsted glass. It ends to be patchy and obscures the underlying capillaries which previously could be seen with the operating microscope through the still translucent epithelium. It is often bilateral and confined at first to the part of the cord in front of the vocal process. Collateral oedema of the ventricular lining may appear, also often bilaterally, producing the appearance that has, in the past, been mistakenly regarded as prolapse or
12
eversion of the ventricle. As the degree of hyperplasia increases the cords may become increasingly bulky, irregular and pale and the worse affected side may be moulded by the more normal one of produce what Kleinsasser has described as duplication of the cord. When atypia is present in a case showing keratinization it is called leucoplakia, Kleinsasseer (1968) classifies the histolotgical characteristics of epithelial hyperplasia into three grades, the first showing no evidence of atypia, the second corresponding to what Norris calls leucoplakia, and the third to what most pathologists would class as coarcinoma in situ. Diagnosis Every case to be submitted to micro-laryngoscopy. Nodularity, induration and ulceration are suggestive features and Kleinsasse has drawn attention to the significance of atypical capillaries. The straight uniform capillaries seen in inflammatory states give way tortuous, cork-screw like vessels, liable to abrupt changes in calibra. Treatment Conventional Treatment
(1) (2) (3) (4)
Attempts to eliminate infection elsewhere in the respiratory tract. Voice rest and speech therapy. Attempts to protect the patient from noxious environmental factors. Advice to avoid smoking, alcohol and any other ingested or inhaled irritant. 13
(5)
The prescription of antibiotics when indicated, expectorants and inhalations.
Surgical Treatment The object is the removal of all or most of the diseased epithelium in anticipation of healing with healthy tissue. Its importance is, not only that it offers a prospect of cure, but also that it removes a pre-cancerous lesion. The operation This consists of decortication usually of the vocal cords but sometimes of the false cords as well. It is performed under a general anaesthetic using a laryngoscope of the Jako or Kleinsasser pattern. The stripping of the diseased epithelium is carried out under the operating microscope with a set of special instruments – scissors, forceps, suction – cautery and knives - all with long (27 cm) rigid shafts which can be used, one in each hand when necessary, through the specially widened laryngoscope. An incision is made along the superior arcuate line curving medially just short of the anterior commissure in front and just short of the vocal process behind to reach the edge of the vocal cord. The D-shaped flap so-defined is then carefully raised form the subjacent vocal ligament and turned medially over the edge of the cord until its attachment along the inferior arcuate line is reached. The diseased
14
epithelium is then trimmed off using scissors along the inferior arcuate line form behind forward. If both cords are involved as is usual, the more hyperplastic one is dealt with first, the less affected one being operated on after an interval of 3-4 weeks, i.e. when the first side has healed completely. Great care must be exercised close to the anterior commissure since the removal of too much tissue here will result in blunting of the glottis with permanent dysphonia. The definition of the subepithelial plane is aided by the subepithelial injection before decortication is commenced of a 1:200000 solution of adrenaline in Normal saline. For a day or two after the operation while the patient remains in hospital he should not attempt to speak and, even more not to whisper. On discharge and for one month when healing is complete, he should use his voice sparingly and never raise it above a quiet conversational tone. The importance of avoiding thereafter whatever irritants may have been judged responsible for the laryngitis in the first place cannot be repeated too often. Contact pachydermia Aetiology Virchow’s opinion that this disease occurs as the result of serious misuse o the voice is called ‘hyperkinetic dysphonia’, vocalizing in a
15
loud, harsh and staccato manner, the voice forced out between cords held adducted with unnecessary tension. Pathology The principal changes are confined to the vicinity of the vocal processes. At first circumscribed injected oedematous swellings appear but as a rule by the time the patient reaches the laryngologist the typical lesions are found. They lie opposite each other, the hyperplastic epithelium being heaped up round a crater, beneath the floor of which lies the vocal process. Very often when the cords are adducted, an elevated part of the edge of the one lesion fits into the depression on the other so that, seen in the laryngeal mirror, the appearance is of a prominence on one side corresponding to a pit on the other. This is entirely in accord with the clinical course of contact pachydermia since carcinoma almost never develops in this part of the larynx. Symptoms The complaint is of a rough hoarse voice with a frequent desire to clear the throat. Diagnosis Direct examination under anaesthesia must be made preferably using the microscope.
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Treatment: An early case in a well-motivated patient may do well on conservative treatment. A period, of absolute voice rest should be followed by regular treatment from a speech therapist where it fails only surgery will offer a reasonable prospect of cure. The operation is micro surgical excision if an endotracheal tube is used it must be positioned to lie at the anterior commissure but the Venturi technique overcomes this difficulty. The aim is to excise the heaped-up hyperplastic epithelium forming the rim of the creater. The base need not be touched. A period of silence followed by voice rest is imperative and the speech therapist must not relax in efforts to maintain a high standard of voice production. Interarytenoid pachydermia The cause of non-specific interarytenoid hyperplasia is unknown. The symptoms are because of the location of the epithelial thickening over the vocal processes, hoarseness is the leading complaint. During quite respiration the lesion appears as a heaping-up of the epithelium between the posterior ends of the aryepiglottic folds at the laryngeal inlet. On phonation, the thickened tissue are compressed into a number of corrugations as the arytenoids come together and present as a sort of cock’s comb, preventing full approximation of the cords posteriorly.
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Deep fissures (Stoerk’s fissures) separate the elevations so formed. Treatment has proved ineffective in this condition since surgical removal of the hyperplastic epithelium is not easy and is likely to result in scarring and failure to improve the voice. Circumscribed epithelial hyperplasia Localized whit e patches appearing on normally nonkeratinized squamous epithelium. Occur in the larynx, usually on the membranous vocal cords. They vary in size and gross appearance from a small prominent white wart to an extensive nodular plaque involving the entire free edge of the cord and with the general texture and colour of cauliflower. They may be papilliferous, the keratin presenting as a sort of shaggy beard. Diagnosis The appearance on mirror examination may reasonably be taken for papilloma or carcinoma, the only characteristic being the striking degree and extent of the keratin formation. Even when the larynx is examined under the microscope the same is true and the eventual decision will depend on the histologist’s opinion. Treatment Conservative treatment has no place in the management, the only course being careful excision of the whole lesion under the operating microscope.
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The complete specimen will be submitted for histological examination. Atrophic laryngitis The larynx characterized by atrophy of the laryngeal mucous membrane and crust formation. Vocal cord polyps These, polypoid degeneration of the cords constitute the commonest cause of chronic hoarseness. They are rare in the young and the very old, commonest in he fifth decade, and affect men twice as the very old, commonest in he fifth decade, and affect men twice as frequently as women. Aetiology The cause has not been certainly identified although in the majority of cases misuse of the voice is apparent. Polyps are particularly likely to occur in patients with hyperkinetic dysphonia i.e. who phonate in a shrill or strident way with unnecessary tension. The vocal polyp is usually a translucent, sessile lesion arising close to the anterior commissure form the subglottic aspect of one vocal cord. In about 20 per cent of cases the condition is bilateral. The surrounding epithelium and the fragile epithelial envelope of the polyp show no sign of inflammatory change although on microlaryngoscopy fine capillary marking is seen. The stroma is as a rule scanty, relatively acellular and distended with glairy yellow-grey exudates.
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Clinical features A constantly hoarse voice is a large mobile polyp may be responsible for choking attacks and diplophonia. A pendulous polyp may be difficult to see with a mirror during inspiration but will be propelled between the cords to lie on top of them during phonation. Diagnosis The appearance of the typical gelationous polyp is diagnostic, particularly when well observed under the operating microscope, but in a cases the excised specimen must be sent for histological examination to confirm its true pathological status. Treatment The polyp should be grasped by suitable small forceps, pulled medially and carefully trimmed off using the scissors designed for the purpose. A week or ten day’s voice rest should be followed by a course of speech therapy with the object of correcting faulty voice production. Polypoid degeneration of the vocal cords (Reinks oedema) Bilateral symmetrical polypoid swelling of the whole length of the membranous part of the vocal cords.
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Aetiology Cause is uncertain but misuse of the voice in the majority of cases. Heavy cigarette smokers. Clinical features At first the patient has a weak and slightly husky voice. Examination early in the course of the disease will show the entirely typical pale translucent fusiform swelling of the cords. Treatment Conservative treatment is almost always ineffective and the condition is best treated by micro-surgery. The operation consists in the excision of an oval strip of epithelium extending form front to back of the swollen cord. On one side the strip should be removed form the upper surface of the oedematous roll, on the other from the caudal aspect, thereby avoiding the risk of an adhesion forming at the anterior commissure. If for technical reasons, this degree of precision is not possible, the second cord should be operated on three or four weeks after the first when healing is complete. Voice rest is important while healing is proceeding and as with vocal nodules and polyps, the help of a speech therapist should be enlisted in the hope of teaching the patient to produce voice with greater relaxation.
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Vocal nodules The synonyms include among other, singer’s ranter’s, preacher’s, heckler’s, teacher’s, hawder’s and screamer’s nodes. Aetiology Nodules occur more frequently in females than males and more often in children than in adult males Misuse of the voice is the invariable cause Pathology and pathogenesis The nodules are almost always symmetrical occurring on both cords at the junction of the anterior with the middle one-third. It is the anterior part of the cord which is active in the production of high-pitched sound and the dynamics of phonation appear to expose this point on the cords to traumatizing pressures during the loud sounding of high notes. It seems that this point of cords is even more liable to trauma when loud vocalization is attempted at the end of expiration. The cords must then more firmly in adduction if a loud high note is to be produced with falling subglottic air pressure. At first the nodules are strictly localized and limited arease of oedema, vascular engorgement focal haemorrhage occur in the connective tissue immediately beneath the epithelium of the free edge of the cord. The overlying epithelium is seen to have under gone a degree of hyperplastic thickening. Subepithelial fibrosis may The collagen undergoing in turn a greater or lesser degree of hyalinization.
22
Nodule remains entirely superficial and does not hinder the rhythmical flowing movement of the epithelium during phonation. Symptoms and Signs An inability to sing high notes softly is almost diagnostic. The voice tires easily and after prolonged use an ache develops n the throat. In long-standing becomes impossible. The diagnosis is confirmed as a rule at indirect laryngoscopy when the typical white sessile nodules are observed at the typical site direct examination under general anaesthetic is necessary. Treatment In the first place voice rest may be necessary for anything from weeks to months and the patient. Micro-surgical removal of the nodes must be considered. The nodes are small and hard to grasp. A small incision is made close to the base to the nodule. The medial lip of the incision may then be seized without too much difficulty; the nodule pulled medially and trimmed of with the curved scissors. Both sides may be dealt with at the same time but silence must be insisted on while the patient remains in hospital and voice rest for a few days more.
23
Reinke oedema of vocal folds The swollen vocal covering is retracted medially so that fine dissecting scissors may detach its superior layer. The inferior membrane is then similarly incised. Only one vocal fold is dealt with at a time to avoid webbing anteriorly. The other fold may be dealt with some 6 weeks later.
Diagram
Diagram
24
Diagram
Vocal fold paralysis The paralysed vocal fold is injected with 0.2-0.4 ml Teflon paste 4 mm deep into the lateral portion of the membranous fold at the junction of its middle and posterior third. A Bruning syringe is used. The paste is seen to expand the fold and subglottis towards the midline. Injection of too much paste may lead to a compromised glottis.
Diagram
25
Diagram
Laser Surgery The use of the carbon dioxide laser for laryngeal surgery has revolutionized the removal of tissue form this area. This technique achieves a bloodless field as the heat of the cutting ray not only vaporizes the area but also seals the ends of associated small blood vessels. Incisions can be made to remove pathological tissue for biopsy of much larger masses, and lesions such as papillomas and leukoplakia can be precisely outlined prior to formal vaporization. Finally, this form of excisional surgery is now being used to remove the early 11 carcinoma of the larynx as the primary and definitive form of treatment. Anaesthesia A technique involving endotracheal intubation with a small diameter tube as for direct laryngocopy is quite appropriate. The difficulty lies in ensuring that there is no risk of fire for the normal
26
endotracheal tube burns when hit by the carbon dioxide laser beam in the presence of high oxygen tension. Special non-metal tubes have now been developed which are treated with a coating of a metal-impregnated material that is resistant to penetration by the laser ray. The cuff of the tube is also vulnerable and should be filled with water (which absorbs carbon dioxide laser light). The tube and cuff should be protected by water-soaped swabs. Also available is a stainless steel malleable endotracheal tube for laser surgery and the high pressure jet injection technique. Provided the anaesthetist and surgeon are properly trained in laser surgery, the presence of aproperly protected anaesthetic tube should be of no more concern than in any other circumstance calling for extreme care in the course of a surgical operation. Every operating theratre employing laser techniques must develop a protocol to ensure that they are used safely. Instrumentation The carbon dioxide laser is the most commonly used laser in otorhinolaryngology. The laser energy in the present generation of lasers is produced form a portable independent source, with the lasers beam passing down a mobile arm, which is attached to the operating microscope, to be reflected down that optical pathway. As the carbon dioxide laser ray is invisible, there is also in line a visible aiming laser ray (a mixture of helium and neon) that produceds a sighting red dot.
27
At this red dot, which itself has no vaporizing power, carbon dioxide laser light will hit the tissue to evaporate it instantaneously when the foot switch is depressed.
28
SELF – ASSESSMET (1)
What is difference between Adult & Child Larynx?
(2)
How does the Laryngoscopy?
(3)
What is difference between Indirect laryngoscopy & Direct Laryngoscopy?
(4)
What is focal length of lens used in MLS?
(5)
What are the hidden areas of Larynx?
(6)
What are the causes of Laryngeal paralysis without hoarseness of voice?
(7)
Teflon paste is injected in which space?
(8)
What are the characteristic feature in tubercular laryngitis?
(9)
Malignancy is more common in anterior half or larynx or posterior half of larynx.
Vocal
Cord
appear
during
direct
(10) What are the characteristics of early malignancy during MLS?
