Management of labyrinthine fistulae secondary to cholesteatoma

Improvements in diagnosis and management of chronic ear disease in general and cholesteatoma in particular have led to a decreased incidence of serious labyrinthine complications. Unfortunately, significant disease still does occur and, if unrecognized, may result in significant morbidity. Labyrinthine fistulae secondary to cholesteatoma cause potentially irreversible symptoms such as hearing loss and vertigo. This study reviews 17 patients who developed labyrinthine fistula secondary to cholesteatoma. Sixteen involved the horizontal semicircular canal and one involved the oval window. The cholesteatoma matrix was removed in all cases and the underlying fistula repaired primarily. Cochlear function was preserved in all patients. Sixteen of 17 patients have had no further difficulty with vertigo beyond the immediate postoperative period. The evaluation and contemporary management of this difficult problem are discussed.

[High resolution computerized tomography of middle ear abnormalities]

BACKGROUND

The aim of this study was to analyze malformed petrous bones with computed tomography and to develop a radiologic score which can help to judge the indication for operative reconstructions.

METHODS

One hundred forty-two petrous bones in 71 patients with unilateral or bilateral microtia, atresia of the external auditory canal, and malformations of the middle ear were evaluated with high-resolution CT.

RESULTS

In 97% of patients with severe auricular dysplasia, there was dysplasia of the middle ear ossicles; in 70% the stapes was malformed. In 32% the oval window was occluded, and in 7% the round window. In 75%, the canal of the facial nerve was displaced, and 16% also showed abnormalities of the labyrinth. A close correlation between the malformation of the auricle and of the middle ear was not found.

CONCLUSIONS

High-resolution CT is necessary for the evaluation of malformed middle ears. Based on the abnormalities described, we propose a radiologic score for the assessment of malformed petrous bones. This consists of the following criteria: external auditory meatus, pneumatization of the mastoid and of the tympanic space, size of the tympanic space, facial nerve, vessels, malleus and incus, stapes, oval and round window. The graded points of each structure are added up to the score, which might range between 0 and 28. This score can help to judge the indication for reconstruction of the middle ear. In bilateral malformation we suggest a middle ear reconstruction of the better hearing ear if the score is greater than or equal to 15, and in unilateral malformation if it is at least 20. In patients with lower scores, we only suggest hearing aids.

Vein graft in stapes surgery

Sealing the opening of the oval window during stapes surgery is essential; it prevents postoperative complications, such as perilymph fistula and sensorineural hearing loss. In this small series of 269 cases with otosclerosis, tympanosclerosis, and congenital ossicular abnormality, vein grafting was used to seal the opening of the footplate. Hearing improvement after surgery was acceptable, and none had total hearing loss or perilymphatic fistula. World literature from the last half of this century on grafting the oval window is reviewed. Absorbable gelatin sponge (Gelfoam) seems to be causing more complications, so its use is highly discouraged. Temporalis fascia, fat, and perivenous loose areolar tissue have been used by different authors at different times in footplate surgery. The opening created in the oval window during stapes surgery must not be left uncovered.

[Obliterative otosclerosis]

In true (grade IV) obliterative otosclerosis, the limits of the oval windows are lost. The insertion of a prosthesis requires drilling and surgical ability. Thirty eight cases of the true obliterative otosclerosis operated in our Department between 1974 and 1992 have been reviewed. Only 6.2% of all the patients operated by us with the diagnosis of otosclerosis had true obliterative otosclerosis. The average preoperative gap in conversational frequencies was 39 dB. In general, the gap closure obtained (13 dB) was slightly lesser than that for otosclerosis. Reobliteration of the oval window may occur in this type of otosclerosis.

Transposition of the facial nerve in congenital aural atresia

It is generally recognized that surgery for congenital aural atresia is difficult. The success or failure of the operation is often directly related to the degree of development of the middle ear. In poorly developed middle ears, the facial nerve may overhang and conceal the oval window niche, making this area inaccessible to inspection, let alone manipulation. The criteria for transposing the facial nerve are; (1) the atresia must be bilateral, (2) there must be preoperative imaging evidence of a stapes and/or patent oval window, (3) there must be no large blood vessels feeding or draining the facial nerve, and (4) facial nerve monitoring must be available. Over the past 2 years, 6 of 94 patients undergoing surgery for atresia were operated with an intent to transpose the facial nerve in order to access the oval window. In all patients, it was impossible to see the oval window niche due to a displaced nerve. In four of six cases, the facial nerve was transposed. The ossicular chain was reconstructed with a total ossicular replacement prosthesis. In no case was there a postoperative facial paralysis or paresis. Facial nerve transposition allows a final chance of achieving serviceable hearing through surgery. The lack of facial nerve injury and the potential for hearing restoration make this procedure feasible in otherwise marginal or poor surgical candidates.

Prostheses for stapes surgery

A variety of different implants are available today for use by the otologic surgeon. All prostheses are well tolerated, and the risks of complication as a result of their implantation are comparable. The most commonly used prostheses are the wire-Teflon piston and the stainless steel bucket handle. Although the otologic surgeon has a wide variety of prostheses to choose from, most have a preference for one particular type. Results of hearing improvement following a successful stapedectomy is more a function of the surgeon's experience than of the type of prosthesis used. As James L. Sheehy, MD, so often says, "if a technique is working well for you, don't change for change's sake" (personal communication, 1994).

Comparison of endoscopic and surgical explorations for perilymphatic fistulas

A history suggestive of perilymphatic fistula (PLF) often prompts repeated tympanostomies to establish a diagnosis and perform a repair. Two patients having multiple previous explorations for perilymphatic fistulas were reoperated, comparing endoscopic and open surgical methods. A third patient with a history consistent with PLF also underwent dual assessment. Endoscopic exploration of the middle ear was performed through a myringotomy and, immediately after, by elevation of a tympanotomy flap. The endoscopic examinations were thorough yet revealed no evidence of perilymphatic fistula; however, the surgical approaches revealed pooling in the oval windows consistent with perilymphatic fistula. These findings were video documented. Recurrent and primary fistulas may be the result of artifact, such as injected anesthetic agents and transudates introduced during surgical explorations, which may interfere with an accurate diagnosis of perilymphatic fistula. Endoscopy of the middle ear is recommended as one method to minimize errors in diagnosis.

Postoperative recurrence of perilymphatic fistulas

Postoperative follow-up study of perilymphatic fistulas (PLFs) showed that recurrence of PLF was not rare and revision was sometimes needed to relieve the symptoms associated with leakage of perilymph. Of the 54 PLF patients surgically treated in our clinic, some sign or symptom of recurrence was found in 9 cases (17%). Vertigo accompanied by spontaneous or positional nystagmus was noted in all 9 cases, while only 3 complained of exacerbation of the existing hearing loss. Revision was indicated in 3 patients since they had no predisposition to spontaneous healing. Various etiological and underlying factors contributed to the incidence of recurrence. Careful operative procedures together with strict postoperative management are required for surgical treatment of PLF.

Impedance transfer: acoustic impedance of the annular ligament and stapedial tendon reconstruction in otosclerosis surgery

The resistance rebuilt around the lower tip of the piston must be the same as that created by the annular ligament of the stapes footplate. Otherwise, the threshold at which an acoustic or barotrauma is able to damage the membranes and hair cells of the inner ear will be lowered. The elasticity reestablished around the lower tip of the piston plays a part in the quality and quantity of hearing for the low frequencies up to 3 kHz. To protect the ear against acoustic traumas, an attempt to rebuild the stapedial reflex is proposed.

[Introduction to the surgery of the middle ear: general principles]

We study the basic guidelines of the middle ear surgery, having as target the recuperation of the anatomic functional integrity of ear. There are different important elements in the quality/quantity of the functional results as follows: The surgery technical method used. The actual pathology in the middle ear. The quality of eustachian tube function. The surgeon's experience and ability and several factors. We review the concept introduced by Wullstein called it tympanoplasty from 1952 till nowadays. Finally, we described the most frequent surgery procedures used in the daily practice.

Stapedectomy technique

This article reviews the evolution of the author's stapedectomy technique from total footplate removal with single loop wire prosthesis and Gelfoam seal to small fenestra stapedectomy with platinum ribbon piston prosthesis and blood seal. The author concludes that the microdrill is effective, safe, and cost effective for performing this procedure. Since using this technique, the author has had no cases of sensorineural hearing loss and few complaints of dizziness or vertigo.

Spontaneous perilymphatic fistula: electrophysiologic findings in animals and man

The case against the occurrence of spontaneous perilymphatic fistulas is presented. Electrophysiologic findings both in animals and in man suggest that small holes in either the round or oval window are not associated with any significant hearing loss. Removal of perilymph may cause some changes in the electrocochleogram that can be reversed when the perilymph is replaced. Tympanotomy surgery, especially when performed with the injection of local anesthetic solutions may result in transudates in the middle ear that are difficult to differentiate from perilymph leaking out from the inner ear. Perilymphatic fistulas were excluded by performing a posterior myringotomy under general anesthesia in 162 congenitally deaf ears. If fluid was present it was suctioned, and if no change occurred on the intraoperative electrocochleogram, it was concluded that no fistula existed. Based on the electrophysiologic findings and the clinical observations in over 240 ears, it was concluded that spontaneous perilymphatic fistulas do not exist. The author accepts that perilymphatic fistulas occur after surgery, especially after stapedectomy, and that they can occur after head injury or barotrauma. However, these should heal readily; persistent or intermittent fistulas are an otologic rarity.

Auditory performance of children with cochlear ossification and partial implant insertion

The management of the profoundly deaf child with a cochlear implant poses a special challenge, particularly when total ossification of the cochlea is present. In this setting, insertion of an electrode array into a child's cochlea is often difficult. Our experience supports the feasibility of partial insertion of a multichannel implant into the basal turn of an ossified cochlea. Five children with ossified cochleae who had undergone partial implantation of a multichannel electrode were compared with the performance of matched controls who had full insertion of multichannel implants. No dramatic differences were detected during a 6- to 18-month follow-up period on selected test measures. These preliminary results suggest that active electrode number may exert a limited effect on performance with a cochlear implant. Drilling out the basal turn of an ossified cochlea in conjunction with partial insertion of a multichannel implant appears to be an acceptable surgical and rehabilitational alternative for placement of a cochlear implant prosthesis in children with complete cochlear ossification.

Surgical management of perilymphatic fistulas: a Portland experience

A comprehensive review of our series of surgical perilymphatic fistula (PLF) repairs, as well as a review of published results from other otologists, suggested an unacceptably high rate of postoperative PLF recurrence. Some recurrences were related to specific events (i.e., coughing, strenuous activity, Valsalva-type maneuvers). However many cases had no apparent cause. Rather, the patients' symptoms recurred spontaneously, and at reoperation the graft was seen to have not "taken," suggesting graft failure rather than "patient failure." After a critical evaluation of current PLF surgical procedures and state-of-the-art concepts of wound healing, we developed a new surgical technique for PLF closure. Combining the use of laser graft-site preparation, an autologous fibrin glue "buttress," and a program of postoperative activity restriction, the new procedure allowed us to achieve statistically significant improvements in graft retention and surgical outcome, with recurrences dropping from 27 percent to 8 percent. In addition, complete resolution or significant symptomatic improvement occurred in 89 percent of patients with vertigo and/or dizziness and in 84 percent with disequilibrium. We conclude that this new surgical technique is an important addition to the otologic surgeon's arsenal for PLF management.

Perilymphatic fistula induced by barotrauma

The association between diving, barotrauma, and the production of perilymphatic fistula has been known for almost 20 years. Forty-eight cases of round and oval window fistulas following diving have been reviewed and essentially corroborate previous findings. Any patient with a history of diving and subsequent sensorineural hearing loss within 72 hours should be suspected of having a round or oval window perilymphatic fistula and surgical exploration and closure of the fistula should be undertaken. Patients who have a loss of hearing, vertigo, nausea, or vomiting following a decompression dive should be re-compressed and if symptoms do not clear, exploration should be performed. Surgical treatment should be executed as soon as possible after the diagnosis is suspected for the best possible results.

Positional audiometry in the diagnosis of perilymphatic fistula

Fifty-eight cases with a presumptive clinical diagnosis of perilymphatic fistula (PLF) are described with the results of a positional audiometric test designed to detect the presence of air in the cochlea. All patients underwent tympanotomy and observations of the middle ear are recorded together with the results of treatment. A definite leak was found in 33 cases and none in 25, but grafting of the round and oval window was performed in all but 10 cases. Pure-tone audiometry was performed before and after a 30-minute period of positioning the patient horizontally with the affected ear uppermost. A change in audiometric thresholds was noted in the group where a presumptive diagnosis of PLF was made, including some of those not found to have leaks at operation. However these changes were not observed in the positional tests of a group of 22 patients with hearing losses attributable to other causes. Also, an abnormal air-bone gap was noted in the PLF group compared with the other group. Although the original two-frequency criteria of earlier studies applied to the positional test did not predict the operative findings (leak or no leak), new data on frequency specific changes are presented. It is possible that fistulas at the oval window may be associated with positional threshold change at 500 Hz, and those at the round window with changes at 8 kHz.

Congenital anomalies limited to the middle ear

Congenital anomalies of the middle ear are occasionally encountered during surgery for conductive hearing loss and are unexpected in patients with no other deformities. We reviewed 12 such patients operated on at The New York Eye and Ear Infirmary from 1985 through 1989. Nine of the patients (75%) had unilateral conductive hearing loss whereas three (25%) had bilateral symptoms. One had bilateral congenital middle ear anomalies. Three patients (25%) had anomalies limited to the malleus and scutum. Five patients (47%) had agenesis of the oval window. After reconstructive surgery, 72% of patients had hearing improvement ranging from 13 to 38 dB. The etiology of these anomalies is discussed and their evaluation and surgical indications are presented.

[Bifenestration--a hearing-improving operation in severe ear malformations]

Bifenestration as an operation for hearing improvement is described in a case of congenital absence of the oval and round window. Besides the classical fenestration of the horizontal semicircular duct, an artificial round window was performed in the middle ear. Due to the acoustic resonance of the mastoid cavity, the resulting conductive loss in the higher frequencies was only 20-30 dB.

Repair of a cerebrospinal fluid perilymph fistula primarily through the middle ear and secondarily by occluding the cochlear aqueduct

A 35-year-old man had a 5-year history of fluctuating hearing loss in his only hearing ear. History and diagnostic tests indicated a perilymph fistula, a diagnosis subsequently confirmed by exploration. Primary and secondary repairs temporarily ameliorated symptoms. A spinal fluid to middle ear fluid pathway was identified by radioactive tracer. A patent cochlear aqueduct indicated on computed tomography scan was found and repaired through a posterior cranial fossa approach. Hearing was preserved, remaining relatively stable during the 2-year follow-up period.

Restoration of hearing with type V tympanoplasty

Type V tympanoplasty with fenestration of the oval window and protection of the round window in a residual hypotympanic cavity can be considered as the last-chance procedure for rehabilitation of hearing in ears with 'canal wall down' or other conditions. The review of 64 cases suggests that restoration of hearing can be adequate in the majority of cases.

Chondrogenic potential of tragal perichondrium: a cause of hearing loss following stapedectomy

Tragal perichondrium is a widely used tissue seal in the oval window following stapes surgery. Autogenous and easily accessible, it is a suitable substance to cover the vestibule in total stapedectomy, and to seal around the prosthesis in small-fenestra stapedotomy. The incidence of complications from the use of perichondrium in this manner is exceedingly low. We report a case where tragal perichondrium in the oval window resulted in the proliferation of cartilage. The cartilage displaced the stapes prosthesis, resulting in a conductive loss. Although the chondrogenic potential of perichondrium is known, we are not aware of other reports implicating this as a cause of failure in stapes surgery. The pertinent clinical and experimental literature regarding chondrogenesis is reviewed. This information suggests that the formation of cartilage from perichondrium in the oval window might be influenced by mechanical trauma and tissue orientation.

[Recurrence of perilymphatic fistula]

Recurrence of the perilymphatic fistula is not rare and may be a tough problem for surgical treatment. This is because a graft is usually applied on the ruptured window(s) from the middle ear and therefore the perilymphatic pressure directly acts on the graft. The recurrence may be caused by a technical failure, use of an unsuitable graft material, poor postoperative bedrest, trauma, increased inner ear pressure, etc. In our clinic, the recurrence occurred in 7 of 48 cases surgically treated. Vertigo accompanied with spontaneous or positional nystagmus was seen in all 7 recurrent cases, while only 2 of them complained of worsening of the existing hearing loss. Re-operation was carried out in two patients. In the first case, closure of the round window by the previous operation was found incomplete, and the perilymph leaked through the gap around the graft. In the second case, closure of the round window was complete, but perilymph leaked from the oval window. In order to prevent the recurrence, the operation should be carefully performed by using strong and adhesive tissue as a graft material, applying a glue between the graft and the inner ear window(s), and keeping strict postoperative bedrest.