Hearing rehabilitation using the BAHA bone-anchored hearing aid: results in 40 patients.

OBJECTIVE: This study evaluates the U.S. experience with the first 40 patients who have undergone audiologic rehabilitation using the BAHA bone-anchored hearing aid. STUDY DESIGN: This study is a multicenter, nonblinded, retrospective case series. SETTING: Twelve tertiary referral medical centers in the United States. PATIENTS: Eligibility for BAHA implantation included patients with a hearing loss and an inability to tolerate a conventional hearing aid, with bone-conduction pure tone average levels at 60 dB or less at 0.5, 1, 2, and 4 kHz. INTERVENTION: Patients who met audiologic and clinical criteria were implanted with the Bone-Anchored Hearing Aid (BAHA, Entific Corp., Gothenburg, Sweden). MAIN OUTCOME MEASURES: Preoperative air- and bone-conduction thresholds and air-bone gap; postoperative BAHA-aided thresholds; hearing improvement as a result of implantation; implantation complications; and patient satisfaction. RESULTS: The most common indications for implantation included chronic otitis media or draining ears (18 patients) and external auditory canal stenosis or aural atresia (7 patients). Overall, each patient had an average improvement of 32+/-19 dB with the use of the BAHA. Closure of the air-bone gap to within 10 dB of the preoperative bone-conduction thresholds (postoperative BAHA-aided threshold vs. preoperative bone-conduction threshold) occurred in 32 patients (80%), whereas closure to within 5 dB occurred in 24 patients (60%). Twelve patients (30%) demonstrated 'overclosure' of the preoperative bone-conduction threshold of the better hearing ear. Complications were limited to local infection and inflammation at the implant site in three patients, and failure to osseointegrate in one patient. Patient response to the implant was uniformly satisfactory. Only one patient reported dissatisfaction with the device. CONCLUSIONS: The BAHA bone-anchored hearing aid provides a reliable and predictable adjunct for auditory rehabilitation in appropriately selected patients, offering a means of dramatically improving hearing thresholds in patients with conductive or mixed hearing loss who are otherwise unable to benefit from traditional hearing aids.

Tinnitus, dizziness, and nonotologic otalgia improvement through temporomandibular disorder therapy.

U.S. Air Force otologic patients seeking care at Wilford Hall Medical Center for tinnitus, dizziness, and/or nonotologic otalgia without an identifiable cause and presenting with temporomandibular disorder (TMD) symptoms in the temple, jaw, or preauricular area or with otalgia at least once a month were referred to a TMD specialty clinic. The patients were provided a dental orthotic and TMD self-care instructions. After 3 months of orthotic wear, the percentages of patients reporting at least moderate symptom improvement of their tinnitus, dizziness, otalgia, and/or TMD were 64, 91, 87, and 92%, respectively. Follow-up telephone calls 6 months after completion of TMD therapy revealed that all patients maintained their symptom improvements. These findings imply that TMD was affecting the patients' otologic symptoms. Patients seeking care for tinnitus, dizziness, and/or nonotologic otalgia without an identifiable cause may have TMD, and their otologic symptoms may benefit from conservative reversible TMD therapy.

Cerebrospinal fluid fistulae in a canine model.

Various diagnostic techniques currently are used to detect the presence of a cerebrospinal fluid fistula. High resolution computerized tomography scanning with the instillation of an intrathecal nonionic contrast medium yields the most accurate diagnostic results. Occasionally, even with optimal conditions, little information is gained other than the confirmation of the presence of a fistula. Intrathecal fluorescein can provide accurate information on the exact location of the fistula. The current study was designed to refine the clinical examination for cerebrospinal fluid fistulae with the use of intrathecal fluorescein. The canine model that we used also served as a vehicle to investigate the histopathologic effects of fluorescein on the central nervous system. We modified a commonly used xenon light source to enable examination with 490 nm light. In the canine model, this allowed accurate visualization of surgically created fistulae using very low doses of intrathecal fluorescein. An examination of the histopathologic features of the central nervous system of the canine model after acute instillation of a higher dose of fluorescein revealed microscopic changes consistent with the introduction of an irritant material. The changes induced by the chemical trauma may explain the serious neurologic sequelae sometimes seen in patients after the instillation of intrathecal fluorescein. Recommendations on the correct dosage of intrathecal fluorescein for diagnosis of cerebrospinal fluid fistulae are proposed.

Surgical rehabilitation of deafness.

Cochlear implants are now an accepted treatment in the rehabilitation of sensorineural hearing impairment. An overview of our understanding of how implants work, the clinical indications, and the current expected results of implantation are briefly reviewed. This is not a comprehensive review but rather a brief summary on the current knowledge of cochlear implants.

Meningiomas intrinsic to the geniculate ganglion.

OBJECTIVE: To present the clinical, surgical and histopathological manifestations of meningioma intrinsic to the geniculate ganglion. STUDY DESIGN: Retrospective study of outcome. SETTING: Three private tertiary and one university (otology/neurotology) referral centers. PATIENTS: Six patients with cranial nerve VII paresis underwent magnetic resonance imaging and/or high-resolution computed tomography for subsequently histologically proven intrinsic meningioma of the geniculate ganglion. An additional six cases were identified in the literature. Most patients were female and ranged in age from 5 to 40 years. INTERVENTION: Total tumor removal via middle fossa and mastoid exposures followed by cable graft VII-VII neuroanastomosis. MAIN OUTCOME MEASURE: Meningioma can occur intrinsic to the geniculate ganglion and produces gradual VIIth nerve paresis as its first symptom. Other sites of predilection may occur extrinsically within the temporal bone or along intracranial venous sinuses at sites of arachnoid villi. RESULTS: Hearing was maintained in each patient, and postoperative House-Brackmann grade III-V facial nerve function was achieved. CONCLUSIONS: Intrinsic meningiomas of the geniculate ganglion rarely occur. However, this entity should be included in the differential diagnosis of a slowly progressive VIIth nerve paresis, especially in young females. Surgical removal and cable graft VII-VII neuroanastomosis is the treatment of choice. Long-term follow-up should be maintained because of the potential for von Recklinghausen's disease.

Preoperative electroneuronography and facial nerve outcome in acoustic neuroma surgery.

OBJECTIVE: To determine whether preoperative electroneuronography (ENoG) predicts facial nerve outcome in patients undergoing acoustic neuroma surgery. STUDY DESIGN: Prospective, consecutive patients undergoing surgery for acoustic neuroma. SETTING: A private tertiary otology and neurotology practice. PATIENTS: One hundred consecutive patients presented for surgical removal of an acoustic neuroma between May 1992 and September 1993. The mean patient age was 49 years (range 17-77). Forty-three percent were male and 57% were female. The mean tumor size was 1.77 cm (range 3 mm to 5 cm). The tumors were removed by a translabyrinthine approach in 59% of patients, via the middle fossa in 40%, and retrosigmoid in 1%. The facial nerve was anatomically intact at the conclusion of the operation in all but one patient. INTERVENTION: Preoperative ENoG in all patients undergoing surgical removal of their acoustic neuromas. MAIN OUTCOME MEASURES: Facial nerve outcome was measured using the House-Brackmann scale immediately after the operation. 5-7 days after surgery, and > 1 year after surgical resection. RESULTS: Preoperative ENoG had no predictive value in determining immediate or eventual facial nerve outcome. CONCLUSIONS: ENoG has no value in predicting the facial nerve outcome in acoustic neuroma patients. The results of this study are similar to reports with smaller series in the literature. Preoperative ENoG has proven useful, in another study from this institution, in predicting the possible presence of a facial nerve neuroma. This test may be helpful in determining the possible etiology of an intracanalicular mass.

Idiopathic Dandy's syndrome.

In 1941 Dandy described patients in whom he had performed bilateral vestibular nerve sections who reported "jumbling" objects in their visual fields when in motion and difficulty walking in the dark. We use the term Dandy's syndrome to describe patients with bilateral vestibular loss as the cause of the above symptoms. The caloric response in these patients is either markedly reduced or absent when the cause is in the peripheral vestibular system. This study explored whether differences exist between those patients in whom the cause is known and those patients with no known cause. We reviewed our experience with 105 patients in whom Dandy's syndrome was diagnosed between 1984 and 1994. Information on their presenting symptoms, findings on physical examination, audiometric status, electronystagmographic findings, laboratory test results, symptom outcome, and cause was collected. Patients with known causes (Meniere's disease, ototoxicity, tumors, vascular disease, trauma, heredity, autoimmune disease, infection) were compared as a group with those with no known cause. Of the 105 patients 34 (32%) had no obvious cause for their symptoms despite an extensive evaluation. This group was similar to those with a known cause except for having a greater preponderance of women (68% vs. 41%, p = 0.018) and an increased likelihood to have normal audiogram findings (53% vs. 19%, p = 0.0009). All other variables, including age, duration of and age at onset of symptoms, physical examination, and electronystagmographic findings did not differ significantly between the two groups. Only 28% of patients with known causes and 40% (p < 0.05) of those with idiopathic Dandy's syndrome had improvement of their symptoms, underscoring the problem with rehabilitation. The results of this study are compared with earlier reports from our and other institutions.

Flow cytometric analysis of primary and metastatic squamous cell carcinoma of the oral cavity and oropharynx.

A retrospective analysis of formalin-fixed, paraffin-embedded tissue from patients with histologically confirmed metastatic squamous cell carcinoma was performed using flow cytometry. Ninety-eight sets of specimens from previously untreated patients with an oral cavity or oropharyngeal tumor and a simultaneous cervical metastatic deposit were analyzed. Normal mucosa and cervical lymph nodes were processed identically and run as controls. All patients underwent surgical resection at Wilford Hall USAF Medical Center or The Eye and Ear Hospital of Pittsburgh between 1980 and 1986. The specimens from 94 patients were technically adequate for interpretation. Diploid histograms in both the primary and metastatic tumors were present in 49 (52%) of 94 patients. Aneuploid histograms in either the primary and metastatic tumors were noted in 45 (47%) of 94 patients. In this group of 45 patients, the primary tumor and cervical metastasis were both aneuploid in 21 (46%), and aneuploid histograms occurred with equal incidence in either the primary or metastasis in the remaining 24 cases. No statistically significant prediction of survival could be made from any correlation with the histograms of either the primary or metastasis. The potential technical problems and limitations of flow cytometry in the determination of DNA content of formalin-fixed, paraffin-embedded tissue and the selection of patients with advanced disease warrant caution in the interpretation of results.

Flow cytometric evaluation of adenoid cystic carcinoma: correlation with histologic subtype and survival.

Adenoid cystic carcinoma is an unusual but capricious tumor of salivary gland origin. Characteristically, these tumors follow a relentless clinical course, although some patients experience prolonged disease-free survival. Tumor size, site, and grade have been shown to correlate with tumor behavior. Recent investigation by others has suggested that DNA ploidy as determined by flow cytometry may provide an additional biologic marker of tumor behavior. This study was undertaken to investigate the relationship of DNA ploidy to tumor grade, biologic behavior, and patient outcome. A retrospective comparison of flow cytometric evaluations of paraffin-embedded formalin-fixed tumor specimens with patient outcome and histopathologic grade was undertaken. Follow-up of 4 to 7 years in 26 patients confirmed that the presence of a solid histologic component in the tumor correlated with the presence of recurrent or persistent disease (p = 0.04). Twenty-two of 28 tumors (78%) were found to be aneuploid on at least one section. Comparison of DNA ploidy with either patient outcome or the presence of a solid component did not achieve statistical significance, although a trend was suggested. This study confirms previous studies demonstrating the validity of histopathologic evaluation of tumor grade in the prediction of the biologic behavior of adenoid cystic carcinoma. However, our findings suggest that DNA ploidy has only limited value as an additional marker of tumor behavior in this patient population.