Burkhardt-Merian’s Aural InstrumentFig. 178. Burkhardt-Merian’s Aural Instrument.A. Curette.B. Myringotome.C. Furunculotome.D. Hook for removal of foreign body.
A. Curette.B. Myringotome.C. Furunculotome.D. Hook for removal of foreign body.
The surgeon holds the speculum in position within the meatus with the left hand, and with the right inserts the knife through the lumen of the speculum along the meatus until its point passes the innermost limit of the furuncle. It is then quickly withdrawn, at the same timeincising the furunclefreely down to its base. Another method is totransfix the furuncleby passing the knife through its base and making it cut outwards through the skin. In a similar manner any other furuncles that may be present are incised or transfixed.
If the inflammatory process, instead of being localized as a furuncle, extends to the subcutaneous tissues, and especially if it is accompaniedby much pain, pyrexia, and occlusion of the external meatus,linear scarificationmay become necessary.
After incision, the contents of the furuncle are rapidly scooped out with the curette (Fig. 178,A). Slight hæmorrhage may occur, but can be arrested at once by plugging the meatus for a minute with a strip of sterilized gauze. The auditory canal is finally syringed out with a warm aqueous 1 in 5,000 solution of biniodide of mercury and firmly plugged with gauze soaked in a 10% solution of carbolic acid in glycerine; a hot fomentation being afterwards applied to the side of the head.
If the operation has been performed under a local anæsthetic (and this should only be done if a solitary furuncle is present), the pain is usually too great to permit of firm packing of the auditory canal. This after-packing, however, should be carried out, if possible, for the following reasons: firstly, it presses out the contents of the furuncle; secondly, it prevents auto-infection from one hair follicle to another; and thirdly, it tends to dilate the auditory canal.
After-treatment.If the furuncles have occurred during the course of a middle-ear suppuration, the gauze plugging must be removed within a few hours after the operation. The ear is then syringed out once or twice daily with a warm solution of lysol or carbolic acid, a small wick of gauze soaked in a 10% solution of carbolic acid in glycerine being afterwards inserted along the meatus.
If there be no accompanying middle-ear suppuration, the packing should not be removed for at least twenty-four hours. The pain produced by the first dressing may be severe, but can be usually avoided by first soaking the gauze with 5% solution of cocaine for a few minutes before removal and then gently withdrawing it whilst the ear is being syringed with a warm aseptic lotion. For the next two or three days it is sufficientto insert a drain of gauze soaked in a 1 in 3,000 alcoholic solution of perchloride of mercury.
Results.Although cure may be expected, it is not uncommon for further furuncles to occur in crops at repeated intervals. This is due to auto-infection of the hair follicles, which to a large extent may be prevented by painting the surface of the auditory canal daily, for at least two or three weeks, with an oil containing a drachm of nitrate of mercury to the ounce.
In the case of diffuse inflammation, although relapses are uncommon, superficial necrosis of a portion of the bony meatus may afterwards occur as a result of involvement of its periosteal lining. If this takes place, stenosis of the auditory canal may afterwards occur from subsequent cicatrization.
Dangers.With ordinary precautions no accident should occur, but the following may be mentioned: (1) if the furuncles are deeply placed, the tympanic membrane may be incised inadvertently, and a middle-ear suppuration may result; (2) a too violent incision may cut through the meatal cartilage posteriorly, and, as a result of septic infection, may give rise to perichondritis of the auricle. This, fortunately, is rare.
Indications.The indications vary, depending on whether there is a coexisting middle-ear suppuration or not.
If there be no middle-ear suppuration.Operation is not urgent, but is justifiable under the following conditions:—
(i)When one ear only is affected.(a) If there be complete deafness due to obstruction of the auditory canal. The question of operation, however, should be decided by the patient, because it may be postponed indefinitely so long as no symptoms occur.
(b) If there be recurring attacks of discomfort or of pain in the ear as a result of eczema, of otitis externa, or of actual pressure of the growth itself. The patient may desire operation to obtain permanent relief.
(c) If there be deafness of the opposite side from other causes, and the presence of the exostoses is causing deafness of the functionally good ear.
(ii)When both ears are affected.In addition to the indications already given, operation is advisable on the worse side if there be almost complete obstruction on both sides, accompanied by recurrent attacks of deafness, owing to the narrowed passage of the auditorycanal becoming repeatedly blocked from accumulation of cerumen or epithelial débris.
Operation is contra-indicatedif previous examination indicates that the deafness is due to a chronic middle-ear catarrh or internal-ear disease, as in these cases restoration of hearing, which is the primary object of the operation, will be impossible.
If middle-ear suppuration be presentoperation is generally advisable.
(i)In acute middle-ear suppurationoperation is urgent if there are signs of retention of pus,providedit is impossible to dilate the lumen of the auditory canal. Before resorting to operation an attempt should always first be made to obtain free drainage, as the obstruction may be due merely to inflammatory swelling of the tissues lining the auditory canal. With cessation of the acute inflammation, this swelling may subside and the lumen of the auditory canal again become patent; and if recovery with healing of the tympanic membrane takes place the hearing may again become normal, rendering the operation no longer necessary.
(ii)In chronic middle-ear suppurationoperation is always indicated if there are symptoms of retention of pus. It is also advisable as a prophylactic measure, although not urgent, even although no acute symptoms are present.
Operation.When there is no middle-ear suppuration.
The operation may be performed either (a) through the external meatus or (b) by reflecting the auricle forward by a post-auricular incision.
Through the external meatus.This method is only indicated if the exostosis is situated at the entrance of the meatus and is pedunculated.
A general anæsthetic is given, the patient being in the recumbent position. The surgeon works by reflected light. After the ear has been thoroughly cleansed a large-sized aural speculum is inserted into the meatus and the outlines of the exostosis are defined with a probe. A small gouge or chisel is used. It is inserted into the meatus in such a fashion that its point presses between the pedicle of the exostosis and the wall of the bony meatus. With successive sharp taps of the mallet, the gouge is made to cut through the pedicle, care being taken that the instrument is not driven in too deeply, on to the tympanic membrane.
The growth, which can now be felt to be movable within the meatus, can usually be removed by grasping it between the blades of forceps, or can be expelled by syringing the ear. After its removal the auditory canal should be plugged for a few minutes with a solution of cocaine andadrenalin chloride. This checks all hæmorrhage, and at the same time enables the surgeon to get a good view of the deeper parts to see if further growths are situated more deeply within the meatus. Such growths, provided they are pedunculated and do not abut on the tympanic membrane, can sometimes also be removed by the same method; much depends on their shape and situation. If sessile or too deeply placed, the operation may have to be completed by reflecting forward the auricle. Before terminating the operation a clear view of the tympanic membrane should always be obtained.
The meatus is finally syringed out with a 1 in 5,000 aqueous solution of biniodide of mercury and dried, a strip of sterilized gauze being inserted into the auditory canal. A simple dressing is then applied to the side of the head.
Other methods of operation through the external meatus.
(a) Perforation of the exostosis, or enlargement of the small passage existing between multiple exostoses, by means of the burr.
Although successful results have been recorded, this method is not advised, as cicatricial tissue almost invariably causes closure of the opening made. To keep the opening patent it is necessary to insert a small lead or silver canula, frequently a source of great discomfort.
(b) If the exostosis has a very fine pedicle, it may be possible to nip through its base with a pair of forceps, but it is not so sure a method as the employment of a gouge and mallet.
(c) Such methods as attempts to destroy the growth by means of the galvano-cautery or by the pressure of laminaria tents should be avoided; they are useless and unsurgical.
By reflecting the auricle forward.This is indicated if the exostoses are multiple, have a broad base, and are deeply situated.
The position of the patient, and the anæsthetic, are the same as in the previous operation. Reflected light may not be necessary.
The ear and the surrounding parts are carefully cleansed and the head is shaved for a short distance over and beyond the mastoid process. A curved incision is madeclose behindthe auricle (Fig. 226), beginning at the upper level of its attachment and extending downwards along the retro-auricular fold. The incision goes down to the bone. The auricle is reflected forward and the soft tissues are separated from the bone until Henle’s spine and the posterior upper margin of the auditory canal are brought into view. Any bleeding, chiefly from branches of the posterior auricular artery, is at once arrested by pressure forceps, ligatures being afterwards applied. The assistant’s duty is to hold the auricle well forward and at the same time to keep the wound dry by swabbing.
The fibrous portion of the canal is carefully separated from the bony portion with the periosteal elevator, the growth, if possible, being exposed without tearing through the thin layer of skin which covers it.
The method of procedure now depends on the character and number of the exostoses present.
(a) If situated superficially, they are removed by chiselling through their base with a gouge. They should be thoroughly removed, if necessary cutting through the normal bone well behind their base.
(b) If deeply placed, they are more easily removed by first chiselling away a part of the upper posterior wall of the external meatus. This is done in the same manner as in the early stage of the complete mastoid operation (seep. 397). If possible the antrum should not be exposed, and care should be taken not to cut too deeply for fear of injuring the tympanic membrane.
(c) If the exostoses spring from the anterior wall, it is necessary to make a T-shaped incision through the posterior membranous portion of the auditory canal in order to bring them into view clearly. This is done with a tenotomy knife, the flaps being held apart by means of forceps. The growths can now be removed by means of the gouge and mallet.
(d) If the obstruction is due to multiple small exostoses forming an annular stricture within the bony canal, it is better to separate the membranous portion completely from the bony meatus. In doing so the skin over the exostoses tears through, so that the membranous portion can be reflected outwards as a finger-like process. To give greater room for the operation, the auricle and fibrous portion are pulled well forward by means of a loop of gauze passed through the lumen of the cartilaginous meatus.
If necessary, reflected light should now be used. To reach the exostoses it may be necessary, as in the previous case, to remove part of the posterior bony wall. With the gouge and mallet the exostoses are carefully chiselled away. They frequently abut on the tympanic membrane, so that their removal without injuring it may be well-nigh impossible. It is of the utmost importance that the field of operation should be kept dry, if necessary by repeatedly mopping out the canal with pledgets of cotton-wool soaked in adrenalin solution. The chief difficulty is to determine the situation of the tympanic membrane. A fine probe is used to discover any existing chink between the growths; this will be a guide to show the direction in which to work. As soon as a small passage has been made, sufficient to allow of a view of the deeper-lying parts, the ear should be syringed out and dried, and a thorough inspection made. The tympanic membrane can usually be seen as agreyish-blue membrane; at other times it can be recognized by touching it with a probe. After making certain of the position of the membrane, the rest of the operation is easy. A small seeker (Fig. 219), such as is used in the mastoid operation, is passed through the opening already made, and with it the deeper limits of the exostoses can be felt. The opening is gradually enlarged by removing the growths piecemeal with the chisel or gouge.
Although the burr is contra-indicated when operating through the external meatus, it is frequently of great service in these cases in rendering the walls of the canal smooth. The disadvantages of using a burr are, that it is less easy to control (unless the surgeon has had considerable experience in using it), and that it destroys all the epithelial lining of the auditory canal with which it comes in contact. It should, therefore, only be used in those cases in which there is a complete ring of exostoses, but should be avoided if the exostoses are limited and if it is still possible to leave untouched a portion of the epithelial lining of the auditory canal.
When the surgeon considers he has successfully removed the obstruction, he should verify this fact by syringing out and drying the ear, and again obtaining a clear view of the tympanic membrane.
The fibrous portion is now replaced by inserting a finger into the cartilaginous meatus and pressing it back into the bony canal, the auricle being meanwhile pulled back into its normal position. The edges of the posterior wound are sutured together and the auditory canal is gently packed with gauze which should be inserted right down to the tympanic membrane. It is not necessary to make special meatal skin flaps, as careful packing of the auditory canal should be sufficient to keep the parts in apposition.
When middle-ear suppuration is present.In acute middle-ear suppurationthe chief difficulty is to decide what operation to perform. As operation is only indicated if there is retention of pus, it is wiser to open the mastoid antrum; the exostosis, if superficial and pedunculated, can also be removed at the same time. If, however, the obstruction is due to multiple and deeply placed exostoses, this part of the operation should be deferred to a later date, that is, after the acute symptoms have subsided.
In chronic middle-ear suppurationthe only operation to be recommended is the complete mastoid operation (seep. 392).
After-treatment.The after-treatment is practically the same whatever operation has been performed. The first dressing need not be done until the third day. The gauze plugging is then withdrawn and the auditory canal is syringed out and dried. If only a single exostosis has been removed the wound surface is small, and it is usually sufficient topuff in some boracic powder and again insert a piece of gauze. This may be repeated every second day, healing usually taking place within two or three weeks. In the case of deeply situated multiple exostoses, especially if removed from the anterior wall, considerable swelling of the soft parts lining the auditory canal may occur as a result of the manipulations. In such cases, after syringing out any existing blood-clots, some cocaine and adrenalin solution should be instilled into the meatus. An aural speculum is then gradually worked into the auditory canal, which is gently mopped out with small pledgets of cotton-wool, and the deeper parts are carefully inspected. Sometimes the torn ends of the fibrous portion, instead of covering the bony walls, are found to project into the auditory canal and to cause considerable narrowing of its lumen. By careful manipulations with the probe or by stroking the edges with tiny pledgets of cotton-wool, these rough surfaces may be smoothed down. It is very important, in the early days of the after-treatment, to prevent any narrowing at the site of the operation. This is one of the chief causes of subsequent failure. The gauze should always be reinserted right down to the tympanic membrane, and if there is not much secretion it should be packed firmly against the posterior and outer portion of the canal in order to prevent subsequent stenosis from the tendency of the cartilage to prolapse forward owing to the soft parts having been separated from the bony canal at the time of the operation.
The wound behind the ear heals very quickly and the stitches can generally be removed on the third or fourth day. Subsequent treatment consists in preventing the formation of granulations over the wound area. This is best accomplished by keeping the auditory canal aseptic and dry. If granulations occur they should be touched from time to time with a saturated solution of trichloracetic acid. If healing has not taken place within two weeks, it will frequently be advantageous to discontinue the gauze packing and, in its stead, to instil drops of pure rectified spirit.
If a middle-ear catarrh with secretion of fluid occurs, owing to the tympanic membrane having been injured, it may be impossible to continue the gauze packing. In these cases only a fine drain of gauze should be inserted into the meatus, the dressing being changed as frequently as may be necessary.
Provided asepsis is maintained, the middle-ear inflammation usually subsides rapidly with healing of the membrane. After healing has taken place, inflation of the middle ear is recommended twice a week, for two or three weeks, in order to aid recovery and to prevent adhesions forming within the tympanic cavity.
Dangers.1. If the exostoses be deeply situated, the tympanic membrane may be injured.
2. If much of the anterior wall of the auditory canal be removed, the temporo-maxillary joint may be opened.
3. It is possible that the tympanic membrane may not be recognized, and, by working too deeply, the labyrinth or the facial nerve may be injured.
Prognosis.Provided no accident has occurred during the operation, a successful result should be obtained. Stenosis, however, may occur from cicatricial contraction if the operation has been incompletely performed.
Before considering the question of removal of foreign bodies, the following points cannot be emphasized too forcibly:—(1) No attempt should be made to remove a foreign body until it is certain that one really exists. (2) Provided there is no middle-ear suppuration, a foreign body left in the ear will very rarely cause any immediate harm. (3) The most serious complications are due almost invariably to ill-advised haphazard attempts to remove the foreign body; as a rule from working blindly in the dark without making use of reflected light.
If a foreign body be suspected, the surgeon should first carefully examine the auditory canal in order to determine its character and position and the condition of its walls. On this will depend the treatment to be employed.
If the object be a living insect it should be killed at once by the instillation of warm oil, rectified spirit, or chloroform. This will cause immediate relief of the intense pain and tinnitus which may have been set up by its movements against the sensitive tympanic membrane.
The methods employed for the removal of a foreign body are syringing, extraction by instruments through the external meatus, and removal by operation by making a post-auricular incision and reflecting forward the auricle.
By syringing.In the vast majority of cases syringing is successful, and therefore should always be tried except under the following conditions:—(a) If the foreign body be of such a nature that it may be driven inwards; for example, a percussion cap for a toy pistol, lying with its concavity outwards.
(b) If there be much inflammation and swelling of the walls of the external meatus, unfortunately frequently due to previous unsuccessful attempts at extraction by instruments. In such cases forcible syringing may cause considerable pain, and in addition immediate removal ofthe foreign body may be impossible owing to the temporary occlusion of the meatus.
Unless urgent symptoms of retention of pus behind the foreign body are present, it is wiser to wait for a few days until the inflammation has subsided, in order that the canal may become more patent and permit of a more favourable opportunity for removal of the foreign body. The auditory canal, in the meanwhile, may be mopped out two or three times a day with pledgets of cotton-wool, and a 1 in 5,000 alcoholic solution of biniodide of mercury afterwards instilled into the ear.
The method of syringing has already been described (seep. 308). The syringe should be a large one with its tip protected by some india-rubber tubing. The point is inserted within the meatus up against the foreign body and the stream of lotion is directed towards any chink which may exist between it and the auditory canal. It may be necessary to use many syringefuls with considerable force before the foreign body can be expelled, but the syringing should be stopped if pain or giddiness are caused.
If the foreign body cannot be removed at the first attempt, drops of rectified spirit may be instilled into the ear several times a day, provided there are no urgent symptoms. This will tend to diminish any swelling of the soft tissues of the external meatus and of the foreign body if it is a vegetable substance. The ear should again be syringed after two or three days. In many cases this will now be successful; if not, the foreign body may be moved gently with a probe (using a speculum and reflected light), great care being taken not to push it further into the auditory canal, and another attempt may be made to remove it by prolonged syringing. If this fails it may be leftin situfor a still longer period, provided there are still no symptoms requiring its immediate removal. In some cases, instead of the instillation of alcohol, a 5% solution of carbolic acid in glycerine or olive oil proves more effectual.
In the case of a hard substance, repeated attempts may be made to dislodge it before resorting to further measures; but in the case of a soft vegetable substance like a pea, it must not be forgotten that moisture tends to make it swell and perhaps will necessitate almost immediate extraction by instruments.
Crocodile ForcepsFig. 179. Crocodile Forceps.Two-thirds size.A, Points of crocodile forceps, full size.BandC, Aural punch-forceps.D, Aural scissors.
A, Points of crocodile forceps, full size.BandC, Aural punch-forceps.D, Aural scissors.
Extraction by instruments.
Indications.(i) If inspection shows that the foreign body can at once be removed by a suitable instrument: for example, a percussion cap the edge of which may be grasped by a pair of forceps (Figs. 179 and193); or a small boot button whose shank, if it faces outwards, may be caught by a small hook.
(ii) If repeated attempts have failed to remove the foreign body by syringing.
(iii) If previous attempts by others have failed, and the foreign body has been pushed in beyond the isthmus, and cannot be removed after prolonged syringing.
(iv) If syringing produces violent giddiness, showing the probable presence of a perforation of the tympanic membrane.
(v) If there be symptoms of acute inflammation of the middle ear or of pus being pent up behind the foreign body.
Operation.An anæsthetic may not be necessary in adults if the foreign body is not too deeply placed within the ear, if its removal appears to be a simple matter, and if the patient is of a placid temperament. Otherwise, unless contra-indicated for some special reason, a general anæsthetic should always be given in children, and it is also preferable in adults for the following reasons:—(1) Inability to remove the foreign body after repeated attempts by syringing usually means that its extraction by instruments will be a somewhat difficult matter. (2) The risk of injury to the meatal walls or tympanic membrane from involuntary movements of the patient during the operation is far greater than the risk of the anæsthetic. (3) If the foreign body cannot be removed through the meatus by means of instruments, the post-meatal operation is indicated. This, if necessary, can be done at once if the patient is under a general anæsthetic.
If no anæsthetic is given the patient may sit up in a chair; otherwise, the recumbent position is advised.
It is usually necessary to use an aural speculum, but if the foreign body be situated near the entrance of the meatus a sufficient view may be obtained by pulling the tragus forward and the auricle backward. Good illumination is essential.
(i)If the body be a soft substance, such as a pea, the core of an onion, or a fragment of wood, it is best removed by fixing into it some form of sharp hook (Fig. 178,D). These hooks vary in shape. They may be curved, or shaped like a crochet-hook, or have the sharp point placed at right angles to the shaft of the instrument.
In the case of a round substance like a pea, especially if it is tightly impacted within the meatus, its removal is sometimes facilitated by first slicing it into pieces by means of a small bistoury.
As a rule, the foreign body is impacted at the junction of the cartilaginous and bony portion of the auditory canal; sometimes, however, it is more deeply situated within the osseous meatus, usually the result of previous attempts to extract it.
In the former case, the instrument is passed along the upper posterior wall of the canal between it and the foreign body, the point of the hook being kept upwards or downwards so as not to project into the auditory canal. The instrument is first passed well beyond the foreign body, and then the shaft is twisted round so that the hook projects into the auditory canal. With a quick movement it is drawn outwards a short distance so that the point of the hook pierces the impacted substance. Gentle traction is now used and in the majority of cases the foreign body can be extracted.
Imray’s Scoop for extracting a Foreign BodyFig. 180. Imray’s Scoop for extracting a Foreign Body.
If this fails, a slightly curved fenestrated scoop (Fig. 180) or curette should be passed, if possible, between the foreign body and the anterior wall of the auditory canal. The hook already fixed into the foreign body prevents it from being driven further within the meatus, whilst the scoop, if it can be got beyond the foreign body, can usually lever it out.
If the foreign body has been pushed in beyond the isthmus and lies deeply within the osseous canal, it is better to pass the hook along the anterior inferior wall of the meatus, because owing to the inclination of the tympanic membrane its anterior inferior margin is much more deeply placed than its upper posterior part.
(ii)In the case of a hard substance, such as a piece of stone, coal, ora bead, blunt hooks may be used instead of sharp ones. They should be passed into the meatusbeyondthe foreign body in the manner already described.
(iii)In other cases, depending on its shape and position, the foreign body is better removed by means of a snare, the loop of which is manipulated round it and then drawn tight in the same manner as in the extraction of a polypus.
The chief points to observe in these manipulations are (a) not to push the foreign body farther in and (b) not to injure the walls of the meatus or the tympanic membrane.
Other methods of extractionare—(1)Drilling through the foreign body, if it is a hard substance, and then inserting a fine hook into the opening so made. (2)The agglutinative method, which consists in dipping a small paint-brush into a concentrated solution of seccotine or glue and then inserting it into the meatus until it comes in contact with the foreign body. The brush is left in this position for several hours in the hope that it may become adherent to the foreign body; if so, on withdrawing the brush from the ear, the foreign body should be extracted with it. This method can only be used provided the ear is kept dry.
These procedures, although said to be successful in a few cases, are not recommended.
After-treatment.If the tympanic membrane and auditory canal have not been injured, it is sufficient to dry the meatus and puff in a little boracic powder. If there be abrasions of the canal, a small strip of gauze should be inserted and changed as frequently as it becomes moist with secretion, the meatus, if necessary, being also syringed out with an aseptic lotion. If there be acute inflammation of the walls of the canal, accompanied by much swelling and purulent discharge, drops of glycerine of carbolic (1 in 10) may be instilled frequently. After the inflammation has subsided, an alcoholic solution of 1 in 3,000 biniodide of mercury may be employed. If the tympanic membrane has been injured, either from the presence of the foreign body itself or from the attempts at extracting it, the treatment is similar to that for an ordinary middle-ear suppuration.
Removal by operation.This may be done in the following ways:—
By means of a post-aural incision.
Indications.(i) If prolonged attempts to remove the foreign body by instruments have failed. This operation becomes imperative if there are signs of retention of pus within the middle ear.
(ii) If the foreign body has been pushed into the tympanic cavity and cannot be removed otherwise. In such cases, if the perforation is largeand the foreign body is small, an attempt may first be made to dislodge the substance by injecting fluid into the middle ear through the Eustachian tube by means of the catheter and syringe (seep. 372). This method, however, is rarely successful.
Operation.The procedure is the same as for the removal of exostoses (seep. 318). After separating the fibrous from the bony portion of the canal, an incision is made through it and the cut edges are held aside with forceps. Usually the foreign body can now be seen lying within the canal. It is best removed by passing a small fenestrated curette beyond it and levering it out. In some cases one of the hooks already mentioned will be found to be more suitable. Forceps should not be used, as they may inadvertently push the foreign body farther in. If the foreign body be very deeply placed, removal of the upper posterior portion of the bony meatus may be necessary. The subsequent steps of the operation and its after-treatment are similar to that already described in the case of an exostosis.
By means of an operation upon the mastoid.
Indications.(i) If the above measures fail to remove the foreign body.
(ii) If there be symptoms of inflammation of the mastoid process, or of internal-ear or of intracranial suppuration.
(iii) If there be facial nerve paralysis the result of pressure from the foreign body.
Operation.The operation performed depends on the condition found. Simple opening of the mastoid antrum may be sufficient in a case of recent middle-ear suppuration, although it is usually necessary also to remove a considerable portion of the posterior wall of the auditory canal before the foreign body can be extracted. If these measures fail, an attempt may be made to dislodge the foreign body by forcibly syringing through the aditus, or by the insertion of a probe through it, into the tympanic cavity. If this likewise ends in failure, it will then be necessary to perform the complete operation. These cases fortunately are rare.
If it be certain that chronic middle-ear suppuration already exists, the complete mastoid operation is indicated.
If it becomes necessary to operate on the mastoid process, owing to other means having failed to dislodge the foreign body, it is wiser, as a rule, to perform the complete operation at once, because, under these circumstances, irreparable destruction must have taken place within the tympanic cavity.
The technique of these operations and their after-treatment are described in the chapter on operations upon the mastoid process (seep. 390).
Stenosis, or stricture of the auditory canal, is practically always the result of traumatism or inflammatory conditions; it is only very rarely congenital.
Indications.(i) If there be deafness of the other ear, and the functionally good ear periodically becomes deaf from obstruction of the narrow passage by cerumen or epithelial débris, and the patient is weary of conservative treatment.
(ii) If there be recurrent attacks of otitis externa.
(iii) If there be retention of pus, the result of inflammation of the external or middle ear, which is not relieved by conservative treatment.
The operation is contra-indicatedif there is accompanying deafness, due to chronic middle-ear or to internal-ear disease, provided there is no suppuration within the external or middle ear.
Operation.The method of operation depends on whether the stricture is membranous, fibrous, or bony in consistence, or whether it is limited or is causing a general narrowing of the auditory canal. It may take one of the following forms:—
Dilatation.This method is not very satisfactory, and is limited to recent cases of membranous or fibrous stricture of the annular variety. After cleansing the meatus, a small laminaria tent is inserted through the stricture, and if the pain is not too severe it is leftin situfor at least twenty-four hours and then withdrawn. The ear is again carefully cleansed, and if possible a larger laminaria tent is substituted. This procedure is repeated until the maximum amount of dilatation has been obtained.
Incision of the stricture.This also is limited to membranous or to fibrous strictures of the annular variety.
The operation, if necessary, may be performed under a local anæsthetic, produced by subcutaneous injections, although usually a general anæsthetic is preferable.
The ear and surrounding parts are surgically cleansed by the ordinary methods. The surgeon works by reflected light. The patient may be in either the sitting or the recumbent position, depending on whether a local or general anæsthetic is given. In the latter case the auditory canal should be filled with cocaine and adrenalin solution before the anæsthetic is administered in order to diminish bleeding as far as possible.
The ear having been dried, a conveniently large aural speculum is inserted, and with a tenotome or a furunculotome radiating incisionsare made through the stricture. One of the small flaps thus made is grasped with a fine pair of tenaculum forceps, and the surgeon cuts through its base, keeping the knife as close as possible to the wall of the auditory canal. Each flap is treated in a similar fashion. Instead of making radiating incisions, the tissue forming the obstruction may be transfixed through its base, the knife being made to cut in a circular fashion right round the auditory canal, keeping as close as possible to its wall.
On completion of the operation, a piece of india-rubber tubing, of as large a size as possible, is inserted into the dilated canal. It should only be removed for the purpose of cleansing and should be at once reinserted. A silver canula, if necessary, can afterwards replace the india-rubber tubing. This canula may have to be worn for months.
This operation is often most unsatisfactory, as the stricture, instead of being annular as first supposed, may be found, on operation, to extend a considerable distance along the auditory canal and, in addition, to be partially due to a general thickening of the underlying bone.
Excision of the stricture.The auricle is reflected forward and the preliminary steps of the operation are performed as already described for removal of a deep-seated exostosis (seep. 319). The surgeon makes a transverse incision with a knife through the fibrous portion of the auditory canal, just external to the stricture, and carries it right round the meatus, thus separating the outer portion of the membranous from the bony canal. The fibrous portion is now pulled outwards by means of a retractor, and the thickened tissue, forming the stricture, is peeled off from the surrounding bony meatus with a small periosteal elevator and so removed. If the stenosis is partially due to thickening of the walls of the canal itself, it may also be necessary to chisel away a considerable portion of its upper posterior part. After completion of the operation a clear view of the tympanic membrane should be obtained.
In this operation a considerable portion of the bony canal is denuded of its epithelial lining membrane, so that there is a special tendency to the re-formation of cicatricial tissue. To prevent this taking place two methods may be employed:—(1) If much of the upper posterior wall of the bony meatus be removed, a post-meatal flap should be made and kept in position by means of a catgut suture carried through the skin behind the auricle. The formation of such a flap is described as a step in the complete mastoid operation (seep. 401).
(2) If no bone be removed, the membranous portion is replacedin situ, the posterior auricular wound closed, and as large an india-rubber tube as possible is inserted into the meatus. A week or ten days later, assoon as granulations begin to form, skin-grafting may be undertaken (seep. 410).
If grafting be not successful, the india-rubber tube or silver canula must be kept constantly within the meatus (only being removed for cleansing purposes) until healing takes place.
The complete mastoid operationis indicated in the case of stenosis occurring in chronic middle-ear suppuration if symptoms of retention of pus occur.
In acute middle-ear suppuration, however, every attempt should be made to avoid operation, as the lumen of the auditory canal may again become patent after the acute inflammation has subsided.
Atresia of the external meatus may be either congenital or acquired.
Indications.(i)In congenital casesoperation is only justifiable if the atresia is due to amembranous websituated in the outer part of the auditory canal and if, as a result of tuning-fork tests and of inflation through the Eustachian tube, it is fairly certain that the middle ear is normal.
Operation is contra-indicated in cases of bony atresia.Although attempts have been made to make an artificial canal in order to restore the hearing power, a successful result has not yet been obtained. Apart from the difficulty of retaining the patency of any canal so made, the accompanying malformation of the middle ear renders a successful result impossible (Paper by author,Journal of Laryngology, &c., March, 1901). Although the tympanic membrane is said to have been exposed by operation in a few cases, experience has shown that the supposed tympanic membrane was really the capsule of the temporo-maxillary joint.
(ii)In acquired casesoperation is indicated if the other ear is deaf; if the site of the occlusion of the auditory canal is in its outer part and is due to membranous or fibrous tissue, and if there is no previous history of middle-ear disease, and if the labyrinth is still intact.
Operation is not advised if the other ear is normal, unless the patient particularly desires it.
Operation is contra-indicatedif there is internal-ear deafness on the affected side and if the other ear is normal; or if there is a definite history of the closure of the auditory canal having been the result of a previous middle-ear suppuration. In the latter case the destructive changes within the tympanic cavity will be so marked that the chances of improving the hearing will be very slight in spite of the most successful operation.
Operation.If the obstruction be due to a fibrous band, an attempt may be made to remove it by excising it by the intrameatal method. In other cases the post-auricular method is necessary.
The chief point to remember is to make a large opening. For this reason the post-auricular method is to be preferred, as a considerable portion of the upper posterior wall can be removed and a large meatal flap fashioned (seep. 401).
Results.If the stricture or point of occlusion of the auditory canal is limited and composed of membranous and fibrous tissues, a good result can be usually obtained, and there is no reason why complete recovery of hearing should not take place if the labyrinth and tympanic cavity are normal.
Unfortunately, as in all cases of stricture, there is a tendency for it to recur.
In this section only the aural polypi which project from the tympanic cavity into the external auditory meatus will be considered; whereas the treatment of granulations, and with them the minute polypi which are still limited to the tympanic cavity, will be discussed in the chapter on operations within the middle ear.
Indications.An aural polypus shouldalwaysbe removed because, apart from the fact that it is a symptom of underlying disease, it may obstruct free drainage of the purulent discharge, and therefore become a source of danger.
Operation.The simplest and the best method isremoval by the snare.
In the case of small and soft polypi, the polypus is removed by traction—formerly calledavulsion—after the snare has been tightened round its pedicle; with a large, tough, fibrous polypus considerable force may be required to tear through its pedicle. This procedure in the case of polypi arising from the region of the tegmen tympani has been known to give rise to fatal meningitis. In such cases the pedicle of the polypus should be cleanly cut through by the snare—so-calledexcision.
As aural polypi are always associated with suppuration, it is especially necessary that the ear should be thoroughly cleansed before operation.
A local anæsthetic (seep. 310) is sufficient in the case of smaller polypi, but if the polypus be large and tough, it is wiser to give a general anæsthetic, such as gas and oxygen. Or a 3% solution of cocaine may be injected into the growth, which, according to Frey of Vienna,renders removal absolutely painless; this, however, has not always been my experience.