Labyrinthine fistula: an unreported complication of the Grote prosthesis.

OBJECTIVES: To alert the otological surgeon that labyrinthine fistula is a rare and avoidable complication of the Grote hydroxyapatite ceramic external auditory canal (EAC) prosthesis. The reasons for its causation and strategies to prevent its formation are discussed. STUDY DESIGN: Case study and retrospective review of the literature. METHODS: Labyrinthine fistula that occurred after the use of the Grote hydroxyapatite ceramic EAC prosthesis is presented. The literature is reviewed retrospectively for various methods of reconstruction of the EAC following canal wall down mastoidectomy. Strategies and principles are outlined to avoid complications associated with reconstruction of the mastoid and EAC. RESULTS: The Grote hydroxyapatite (HA) prosthesis is a reliable prosthesis for reconstruction of the external auditory canal (EAC) in the absence of a draining mastoid cavity or cholesteatoma and with adequate soft tissue cover. Contact of the medial end of the prosthesis with the lateral semicircular canal must be avoided. Immobilization or rigid fixation and avoidance of infection are essential for optimal prosthesis stability and osseointegration. Covering the prosthesis with vascularized soft tissue appears to be important for the achievement of a successful reconstruction. CONCLUSION: The Grote prosthesis is safe and effective provided it does not contact the lateral semicircular canal, is stabilized, and covered by vesicular tissue, in the absence of infection.

Facial reanimation with jump interpositional graft hypoglossal facial anastomosis and hypoglossal facial anastomosis: evolution in management of facial paralysis.

When viable proximal facial nerve is inacessible, facial nerve paralysis has been classically managed with the hypoglossal facial anastomosis (HFA) for at least the past 70 years. While this procedure has proven its reliability, its problems with hemilingual atrophy (speech deglutition, drooling, mastication), hypertonia, synkinesis, and mimetic deficits indicate the need for a more perfect solution for facial paralysis. The jump interpositional graft hypoglossal facial anastomosis (JIGHFA) along with gold weight lid implantation and electromyographic (EMG) rehabilitation achieves substantial facial reanimation without hemilingual deficits. We present our results in 18 patients who underwent JIGHFA along with gold weight lid implantation and EMG rehabilitation for facial paralysis. These results were compared with those from published series of 30 patients treated with HFA with EMG rehabilitation evaluated with objective (House-Brackmann) criteria. Anonymous retrospective information from questionnaires from 22 of 48 patients who were treated with the classic HFA was also presented. In properly selected patients, the JIGHFA technique is capable of achieving substantial facial reinnervation (House-Brackmann grade III or better) in 83.3% of the patients without hemilingual sequelae which was seen in 45% of the HFA patients. In contrast to the HFA, this procedure can be used by patients with concomitant lower cranial nerve paralysis (except hypoglossal), and bilateral facial paralysis. Hypertonia, synkinesis, and lagophthalmus were less symptomatic in the JIGHFA patients. Mimetic expression was not improved in the JIGHFA population compared with the HFA group.

A review of 308 cases of revision stapedectomy.

OBJECTIVE/HYPOTHESIS: Identify causes of primary and revision stapedectomy failure in 308 patients, assess whether these are different based on source of initial surgery, and evaluate hearing results in revision stapedectomy to improve outcome. STUDY DESIGN: Retrospective, nonrandomized chart review of patients undergoing revision stapedectomy in a referral otology practice in a large metropolitan region. MATERIALS AND METHODS: Intraoperative findings, preoperative and postoperative revision stapedectomy air and bone conduction pure-tone averages, speech discrimination scores, postoperative air-bone gaps, complications, and repeated revisions were noted in 308 patients. RESULTS: Leading causes of primary stapedectomy failure included dislocated prosthesis (24.4%), inadequate prosthesis length (14%), long process resorption (14%), and fibrous adhesions (13.6%). Revision stapedectomy air-bone gaps were less than 10 dB in 80% and greater than 30 dB in 6.8% of cases. Increased sensorineural hearing loss occurred in 0.8% of revision stapedectomy cases. Five of seven cases of vertigo associated with primary stapedectomy resolved after revision surgery. CONCLUSION: Revision stapedectomy by experienced surgeons is highly effective in attaining successful air-bone gap closure in 80% and improved closure in 84.8% of operative cases. Risk of vertigo and/or sensorineural hearing loss was not any higher in this patient population when compared with reports of primary stapedectomy.

Prognostic significance of intraoperative facial nerve stimulus thresholds.

OBJECTIVE: Intraoperative facial nerve monitoring has reduced the incidence of facial nerve paralysis associated with acoustic neuroma surgery, but poor facial nerve outcomes continue to occur. Intraoperative prediction of facial nerve outcome would be advantageous in patient management and counseling. This study seeks to evaluate intraoperative facial nerve stimulus thresholds as a tool for predicting postoperative facial nerve outcome. STUDY DESIGN: This study is a prospective clinical study of the prognostic value of intraoperative stimulus thresholds. SETTING: The study was performed at a tertiary referral center. PATIENTS: There were 109 patients undergoing excision of acoustic neuromas included in this study. INTERVENTIONS: The minimum current required to stimulate the facial nerve at the brain stem was prospectively recorded after excision of the acoustic neuroma. MAIN OUTCOME MEASURES: Facial nerve outcome was evaluated by the House-Brackmann grade. RESULTS: A statistically significant relationship was found between poor initial facial nerve outcome and higher stimulus thresholds. Long-term impaired facial function was also more common in the higher stimulus group compared to that of the lower stimulus groups. CONCLUSIONS: Although these findings suggest that intraoperative stimulus thresholds have prognostic potential, other prognostic factors should also be considered and additional research is needed.

Evaluation and management of spontaneous temporal bone cerebrospinal fluid leaks.

Spontaneous temporal bone cerebrospinal fluid leak may be defined as a leak without an apparent precipitating cause. These transdural fistulas occur rarely, and diagnosis is predicated upon a high index of suspicion. Leaks have been reported through both middle and posterior fossa defects, although the vast majority involve the middle fossa plate. In a previous study we reported 7 cases of spontaneous temporal bone cerebrospinal fluid leaks, all involving the middle fossa tegmen. Upon further review of these cases and 5 previously unreported cases, the defect was localized to the tegmen tympani in 9 of the total 12 cases. Diagnostic methods are discussed, with the importance of high-resolution computed tomography stressed. The role of contrast cisternography is also evaluated. An outline for surgical management is presented based upon residual hearing and defect location and accessibility. A transmastoid procedure offers the advantage of visualization of both the middle and posterior fossa plates, and this approach can be supplemented with an obliterative procedure when indicated. The middle fossa approach provides optimal exposure of the tegmen plate with less likelihood of ossicular injury when dealing with tegmen tympani defects. Adjuncts to surgical therapy include intrathecal fluorescein dye and continuous postoperative lumbar cerebrospinal fluid drainage.

Management of traumatic facial nerve paralysis with carotid artery cavernous sinus fistula.

Massive skull base injuries require detailed preoperative neurological and neurovascular assessment prior to undertaking surgical repair of isolated cranial nerve deficits. We present the management of a patient with traumatic facial paralysis, cerebrospinal fluid leak, and carotid artery cavernous sinus fistula as the result of a gunshot wound to the skull base. The carotid artery cavernous sinus fistula was ultimately controlled with super-selective embolization via the vertebral artery. The facial nerve injury was then safely treated with mobilization of the labyrinthine and vertical segments to allow a primary anastomosis.

Cerebrospinal fluid rhinorrhea and recurrent meningitis.

Cerebrospinal fluid rhinorrhea is the result of transdural communication between the subarachnoid space and the skull base. A transdural fistula may originate from the anterior, middle, or posterior cranial compartments. All skull-base sites of leakage potentially lead to the nasal cavity. Recurrent meningitis is commonly associated with such a direct source of bacterial contamination. Organisms associated with recurrent meningitis secondary to cerebrospinal fluid leaks are commonly found in the upper respiratory tract. We report a case of recurrent meningitis in a 5-year-old girl that highlights the problem of cerebrospinal fluid rhinorrhea, and we discuss etiology, current diagnostic techniques, and surgical management.

Otologic disease in AIDS patients: CT correlation.

The contrast-enhanced computed tomographic (CT) scans of the temporal bone and brain in 18 patients with otologic disease and acquired immunodeficiency syndrome (AIDS) were retrospectively reviewed. Seven scans revealed middle ear and mastoid disease; three scans were consistent with central nervous system (CNS) pathology; and eight scans demonstrated no abnormalities. CT scanning was found useful in localizing otopathology and diagnosing CNS toxoplasmosis, aural polyps, osteomyelitis, mastoiditis, and middle ear effusion due to hypertrophic lymphoid tissue. The authors conclude that AIDS patients with sensorineural hearing loss should undergo contrast-enhanced brain CT scans to rule out CNS pathology; AIDS status does not alter criteria for CT scanning in patients with conductive hearing loss; and that images of the nasopharynx should be included on temporal bone CT scans of patients with conductive hearing loss in order to exclude eustachian tube obstruction by hypertrophic lymphoid tissue.

Intraoperative monitoring of facial nerve function in cerebellopontine angle surgery.

Facial nerve paralysis associated with cerebellopontine angle surgery has been reported to range up to 26% in a recent series. Various methods of intraoperatively monitoring the facial nerve have been developed to reduce the incidence of facial paralysis. We report our experience with an intraoperative monitoring technique using intramuscular EMG electrodes to detect subclinical electrical responses that were amplified and made audible to the operating surgeon after gating stimulus artifacts. A 3.6% incidence of facial paralysis in 111 consecutive cases with this intraoperative monitoring method compared with 14.5% in 207 previously unmonitored cases indicates significant reduction of this complication in cerebellopontine angle surgery (p less than 0.001). Along with this reduction in facial paralysis, an increase in the percentage of partial facial paresis was observed in the monitored group (p less than 0.05). The percentage of those with intact facial function was similar in the monitored (82.0%) and unmonitored groups (78.3%).

Pneumocystis carinii in the temporal bone as a primary manifestation of the acquired immunodeficiency syndrome.

Extrapulmonary infection with Pneumocystis carinii is rare and is usually associated with severe systemic illness. We report, in two patients, the histologic, ultrastructural, and monoclonal cell surface antibody identification of P carinii in otic polyps. Both patients had serum antibody to human immunodeficiency virus. These P carinii infections in the temporal bone are unusual in their location and in the apparent absence of associated pulmonary infection. This otologic presentation was the primary manifestation of the acquired immunodeficiency syndrome.

Electromyographic rehabilitation of facial function and introduction of a facial paralysis grading scale for hypoglossal-facial nerve anastomosis.

For reinnervation of facial paralysis, the XII-VII nerve anastomosis provides tone and mass contraction but rarely allows selective muscle control. The efficacy of EMG rehabilitation was evaluated in 30 patients who had no coordinated control of facial muscles. EMG signals from bilateral homologous facial muscle sites were converted into computer-compatible waveform traces and displayed on a video monitor. This facilitated modification of neuromuscular responses using behavioral shaping techniques. A six-point Facial Nerve Grading Scale was introduced for hypoglossal-facial nerve anastomosis to assess the results of EMG rehabilitation. Rehabilitation lasted from 3 to 18 months. Ten patients (33%) achieved the highest possible grading (II) with symmetry and synchrony of function and spontaneity of expression; 17 (57%) reached grade III, which allowed voluntary control of eye and mouth function; 3 (10%) showed minimal gains. It is suggested that neural plasticity allows therapeutic manipulation of central facilitory and inhibitory mechanisms, and possible unmasking of neural connections between the ipsilateral VII and XII nerve motor nuclei which leads to improved facial function.

Hypoglossal-facial nerve anastomosis and electromyographic feedback rehabilitation.

Electromyographic (EMG) feedback has been proposed to enhance rehabilitation following hypoglossal-facial nerve anastomosis. Sixteen of 25 patients who underwent hypoglossal-facial nerve anastomosis with and without postoperative EMG rehabilitation were videotaped for evaluation of facial movement by four observers unaware of these patients' rehabilitation therapy. Using a House Facial Nerve Grading System and intragroup comparison, a trend discernible in this preliminary study indicates a chance for better facial function with EMG feedback rehabilitation.

Intraoperative real-time monitoring of brain stem facial evoked response (BFER).

Injury to the facial nerve is of concern in surgery of cerebellopontine angle tumors. The crossed acoustic reflex provides a way to monitor the ipsilateral facial nerve with the auditory stimuli delivered to the contralateral side. Using the method of optimum digital filtering, it is possible to monitor the resulting brain stem facial evoked response (BFER) in real time. This paper presents preliminary experiences in more than 18 such operations monitored using this method. This preliminary study demonstrates a trend for a high (88.8%) correlation between BFER and postoperative facial nerve function. Identical latencies from simultaneous BFER and facial nerve recordings along with findings after facial nerve transection suggest that some portion of the complex BFER waveform derives from facial nerve depolarization.

Real-time monitoring of brainstem auditory evoked response (BAER) during cerebellopontine angle (CPA) surgery.

The signal-to-noise ratio of brainstem auditory evoked responses (BAER) can be greatly enhanced by use of optimal digital filtering before averaging. This permits accurate assessment of auditory nerve status every 5 to 10 seconds, making real-time intraoperative monitoring possible. The major advantages yielded by real-time monitoring--in our experience thus far--have been identification of potentially adverse functional consequences of apparently uneventful surgical maneuvers, reducing postoperative dysfunction, early indication of potential for improved clinical function, and potential identification and localization of neural tissue in the face of absent surgical landmarks. Examples of these advantages will be provided from case studies, and the possibility that real-time monitoring may improve ability to preserve hearing will be discussed.

Cholesteatoma vs. cholesterol granuloma of the petrous apex.

Lesions involving the petrous apex are rarely encountered in clinical practice. This directly affects the ability of the otolaryngologist to diagnose and effectively treat these lesions. Greater physician awareness and increased technologic capability are leading to more effective management of pathologic conditions involving this area of the temporal bone.

Acoustic neuroma presenting as sudden hearing loss with recovery.

In our series of patients operated on for acoustic neuromas at New York University Medical Center between 1974 and 1983, 13% (17 of 133) had sudden hearing loss. Of these, approximately 23% (four of 17) had recovered auditory function before acoustic neuroma extirpation. Three patients spontaneously recovered, while one improved with steroid therapy. Contrast computerized tomography demonstrated a widened internal auditory canal and evidence of cerebellopontine angle tumor, respectively, in 88% and 59% of patients with sudden hearing loss and acoustic neuroma. Clinical characteristics suggesting acoustic neuroma as the cause of sudden hearing loss with or without auditory recovery could not be identified in our series. Our data support the rationale that patients with unilateral sudden hearing loss, even with recovery, must be evaluated for a possible cerebellopontine lesion.