Oculoplastic surgical techniques for protection of the eye in facial nerve paralysis.

OBJECTIVE: To describe an algorithm for medical and surgical management of corneal exposure secondary to seventh cranial nerve paresis. STUDY DESIGN: A retrospective review of 54 patients requiring surgical intervention for seventh cranial nerve paresis was performed. SETTING: Patients underwent outpatient procedures at a tertiary care facility. RESULTS: 31 men and 23 women, with a mean age of 55.7 years, were included in this study. They included 45 patients with involvement of the facial nerve at the time of surgery, 3 with inflammatory processes, 2 with central palsies, 1 with a traumatic paralysis, and 3 with idiopathic palsies. All 54 patients were treated both medically and surgically. Fifty-two patients underwent gold weight placement, and 39 patients underwent surgical repositioning of their lower eyelids; 24 of those patients had supplemental ear cartilage grafts inserted as well. Five patients had brow ptosis repairs, and 13 had tarsorrhaphies (9 temporary and 4 permanent). Twelve patients had confluent epithelial defects of >50% of their corneal surface, and 33 patients had smaller disruptions of their corneal epithelium. Three patients had minor complications secondary to surgical intervention. Thirty-seven patients had isolated seventh nerve palsies, and 17 patients also had fifth nerve pareses affecting their ocular surfaces. The average preoperative lagophthalmos was 6.3 mm, and the average postoperative lagophthalmos after all ocular procedures was 1.6 mm. The mean follow-up time was 19.7 months. CONCLUSIONS: Treatment options for seventh cranial nerve deficits are reviewed. A decision-making process for the treatment steps is proposed and analyzed.

Immunoblotting analysis of schwannomin/merlin in human schwannomas.

HYPOTHESIS: Absent or reduced expression of schwannomin/merlin is associated with tumorigenesis of sporadic schwannomas. BACKGROUND: The neurofibromatosis type 2 (NF2) gene frequently is mutated in sporadic vestibular schwannomas. The protein product of the NF2 gene is called schwannomin or merlin. Little is known about the mutated forms of schwannomin/merlin present in schwannomas. METHODS: To investigate further the role of schwannomin/merlin in schwannoma tumorigenesis, immunoblotting experiments were performed. Antischwannomin/merlin-specific antibody that recognizes amino terminus of the protein was used to determine the expression levels of schwannomin/merlin in 16 sporadic vestibular schwannomas, 1 NF2-related vestibular schwannoma, and 5 spinal schwannomas. RESULTS: The antibody detects a protein of approximately 66 kDa in the Triton X-100-insoluble fraction of tumors. The expression of schwannomin/merlin was severely reduced, <35% of control, in 11 (50%) of 22 sporadic schwannomas and in 1 NF2-related vestibular schwannoma. The intensity of 66-kDa schwannomin/merlin band was moderately reduced, from 35-60%, in 7 (32%) of 22 schwannomas compared to the expression levels found in the human brain. Truncated forms of schwannomin/merlin were identified in three tumors with moderately reduced schwannomin/merlin. CONCLUSIONS: These results provide new evidence that inactivation of schwannomin/merlin is an important factor in tumorigenesis of sporadic schwannomas.

Retrospective blinded review of magnetic resonance imaging in patients with central electronystagmography findings.

OBJECTIVE: To evaluate the magnetic resonance imaging results (MRI) of patients with electronystagmography (ENG) suggestive of central vestibular dysfunction and to determine if MRI abnormalities correlate with ENG findings. STUDY DESIGN: Retrospective blinded case review. SETTING: A regional neurotology center. PATIENTS: Patients with ENG suggesting central vestibular dysfunction were identified (n = 30). An age-matched group of patients with normal ENG results were used as controls (n = 28). MAIN OUTCOME MEASURES: MRI abnormalities in cerebellum, brain stem, cerebellar peduncles, and central ENG findings. RESULTS: Twenty-one patients with abnormal MRI results of the vestibular pathway were found, 15 with abnormal and 6 with normal ENG results. MRI correlation with ENG findings has a better predictive value in older patients than in younger patients. Sixteen patients had MRI evidence of vascular compression, seven of whom had abnormal and nine of whom had normal ENG results. CONCLUSIONS: This study suggests that a detailed review of MRI images of the vestibular pathway is warranted, and, in patients with central ENG abnormalities, MRI may support the diagnosis of central vestibular dysfunction. MRI cannot support central vestibular dysfunction caused by vascular compression.

Rare lesions of the posterior fossa with initial retrocochlear auditory and vestibular complaints.

OBJECTIVE: To catalog a series of rare lesions of the posterior fossa that appeared with unusual initial retrocochlear symptoms and signs and to make the reader more aware of these unusual lesions with a view to improving initial assessment and treatment planning. STUDY DESIGN: The study was a retrospective case review of seven patients. SETTING: Multidisciplinary team evaluation in a tertiary hospital referral center. PATIENTS: Patients with unusual lesions of the cerebellopontine angle and posterior fossa with initial retrocochlear symptoms and signs were included. INTERVENTIONS: Diagnostic and therapeutic. MAIN OUTCOME MEASURES: Hearing preservation and balance function. RESULTS: The rare lesions presented include two aneurysms of the anterior inferior cerebellar artery, one giant basilar artery aneurysm, and one each of the following neoplasms: endodermal cyst, choroid plexus papilloma, cavernous angioma, and ependymoma. CONCLUSIONS: A close working relationship among the otolaryngologist, neurotologist, neurosurgeon, and neuroradiologist is necessary to accurately evaluate these unusual cerebellopontine angle lesions and effect the best treatment outcome.

Reduced expression of schwannomin/merlin in human sporadic meningiomas.

OBJECTIVE: The neurofibromatosis type 2 gene is frequently mutated in sporadic meningiomas. The protein product of the neurofibromatosis type 2 gene is called schwannomin or merlin. Its expression in leptomeningeal cells from which meningiomas are derived and the characteristics of mutated forms in meningiomas, to our knowledge, have not been previously studied. METHODS: Immunoblotting and immunoprecipitation experiments with two specific antibodies were used to determine the size and subcellular distribution of schwannomin/merlin in rabbit and human brain tissue and established human leptomeningeal LTAg2B cells. Immunoblotting was used to determine the expression level of schwannomin/merlin in 14 human sporadic meningiomas. RESULTS: Both antibodies detect a protein of approximately 66 kDa, which is predominantly expressed in the Triton X-100-insoluble fraction of the brain and LTAg2B cells. The levels of schwannomin/merlin were severely reduced in eight tumors (57%) when compared with the expression levels in the human brain, LTAg2B cells, and the remaining six meningiomas. All six tumors with the normal schwannomin/merlin expression were of meningotheliomatous type. In contrast, all other histological types and one meningotheliomatous tumor with psammoma bodies were deficient in the 66-kDa schwannomin/merlin. Although nonsense mutations leading to premature stop codons are common in the neurofibromatosis type 2 gene in meningiomas, we found no evidence of truncated schwannomin/merlin forms in the tumors analyzed. CONCLUSION: The absence of complete schwannomin/merlin in almost 60% of primary sporadic meningiomas seems to be an important factor in meningioma tumorigenesis. The development of meningotheliomatous meningiomas is probably linked to alterations in other oncogenes or tumor suppressor genes.

Long-term effects of Ménière's disease on hearing and quality of life.

OBJECTIVE: To evaluate long-term hearing results and quality of life in patients with Ménière's disease. STUDY DESIGN: Detailed audiometric evaluation and disease-specific as well as global health quality evaluation of patients with Ménière's disease. SETTING: Ambulatory evaluation was conducted in a large multispecialty clinic. PATIENTS: Ménière's disease in only one ear, were at least 1 year posttreatment, were < 65 years of age, had no neurologic or psychologic disorders, and lived within driving distance of the ambulatory clinic. MAIN OUTCOME MEASURES: Audiometry, the Hearing Handicap Inventory, Dizziness Handicap Inventory, Tinnitus Handicap Inventory, and SF-36 Health Survey. RESULTS: No statistically significant differences in long-term hearing results were detected from natural history in medically or surgically treated patients with Ménière's disease. A significant disease-specific symptom handicap was detected. The global health handicap was greater for emotional disability than for physical disability. CONCLUSIONS: Medical and surgical treatment does not significantly influence hearing results in Ménière's disease. Patients with Ménière's disease have a greater emotional disability than a physical disability.

Cochleosacculotomy for the treatment of Menière's disease in the elderly patient.

Cochleosacculotomy is a surgical option for the treatment of incapacitating vertigo in elderly patients with Menière's disease. This procedure was performed in nine patients (mean age: 73 years) for control of vertigo and/or drop attacks. The average follow-up period was 29 months. Vertigo was controlled in eight of nine patients, but hearing worsened in all but one patient. No patient developed a transient increase in vertigo in the postoperative period. Cochleosacculotomy should be considered in elderly patients with recurrent vertigo and severe non-fluctuating sensorineural hearing loss who would otherwise be candidates for labyrinthectomy.

Adenomatous lesions of the temporal bone immunohistochemical analysis and theories of histogenesis.

Adenomatous lesions of the temporal bone represent a diverse group of neoplasms. At least three histopathologic patterns have been described: glandular; ribbon-like, or "festooning;" and aggressive papillary. Combinations of glandular and ribbon-like histologies in the same lesion are not uncommon. The glandular and ribbon-like histologies have been associated with carcinoid tumors, and the aggressive papillary tumor has been considered a separate entity. Recently, the endolymphatic sac has been proposed as the site of origin of the aggressive papillary lesions. Previous reports have described neuroendocrine properties with characteristics embracing the three histologic types. The authors postulate that the neural crest is the site of origin of this unusual group of neoplasms. Immunohistochemical analysis on the pathologic specimens of patients with adenomatous lesions of the temporal bone was performed to test this hypothesis. From 1975 to 1992 seven patients were treated at the Cleveland Clinic Foundation with a diagnosis of middle ear adenoma. A panel of special stains for neuroectodermal markers, including synaptophysin, chromogranin, neuron specific enolase, calcitonin, and serotonin was used on the paraffin-embedded formalin-fixed specimens. Three lesions were also evaluated by electron microscopy, all demonstrating dense core, intracytoplasmic granules. Three ribbon-like tumors were positive for synaptophysin and chromogranin, and two of these were positive for serotonin. One glandular tumor was positive for synaptophysin, and an aggressive papillary tumor was positive for synaptophysin and neuron specific enolase. An additional papillary tumor was referred following a third recurrence without accompanying immunohistochemical data. Cholesteatoma-like material was identified with a few glandular cells interspersed, all negative by immunohistochemical evaluation. The seventh specimen, initially diagnosed as papillary adenoma on light microscopy, was not studied by the aforementioned stains, and was later identified as a papilloma of sinonasal origin. The neural crest gives rise to pluripotential stem cells with widespread anatomic distribution, including the temporal bone. Because immunomarkers used in this study are specific for neuroectodermal differentiation, results suggest that temporal bone adenomas have neuroendocrine characteristics and could be derived from the specialized neuroectoderm of the neural crest.

Retrolabyrinthine transtentorial approach to lesions of the anterior cerebellopontine angle.

Various surgical approaches to the cerebellopontine angle have been used for removal of acoustic neuromas. A retrolabyrinthine transtentorial approach has been developed that allows (1) access to the anterior cerebellopontine angle and all portions of the basilar artery, (2) extra dural retraction of the lateral sinus and cerebellum while avoiding the vein of Labbé, and (3) preservation of hearing. This approach allows good exposure of tumor and accurate visualization of cranial nerves. To avoid complications, control of spinal fluid is mandatory and great care must be taken to avoid injury of the cranial nerves. The retrolabyrinthine or translabyrinthine transtentorial approach enables skilled neurosurgeons and neurotologists to gain access to lesions that are located in areas difficult to approach.

Cancer of the periauricular region.

Cutaneous carcinoma of the auricular and periauricular region can be diagnosed early and often can be cured; however, many of these tumors become difficult to treat because of local spread and regional metastasis. Those tumors that are not treated early often require more aggressive treatment with ear canal resection, partial temporal bone resection, or even parotidectomy and radiation therapy. Mohs histographic surgery combined with conventional excision affords the best marginal control for local eradication of these tumors.

Squamous cell carcinoma of the external auditory canal.

Squamous cell carcinoma of the external auditory canal is an unusual head and neck malignancy. It may occur in an ear in which there had previously been chronic inflammation, either in the external canal or middle ear. However, in most cases the etiology of the cancer is unclear. Treatment modalities have ranged from full therapy irradiation to formal temporal bone resection. Morbidity and mortality with these treatment plans alone have not been satisfactory. The purpose of this paper is to describe diagnostic and therapeutic approaches to squamous cell carcinoma of the external auditory canal used in the Department of Otolaryngology and Communicative Disorders of the Cleveland Clinic Foundation for the last 10 years.

Intact canal wall tympanoplasty with mastoidectomy for cholesteatoma: long-term follow-up.

One hundred four ears operated for cholesteatoma using the intact wall technique were studied in 1981. In the 1981 study, there was a 7% recurrence rate in adults and a 25% recurrence rate in children after a 5-year follow-up. Recognizing that chronic otitis media is often not controlled by surgery, long-term follow-up is necessary to evaluate a particular operative approach to control the disease and restore function. The purpose of this study is to reexamine the series of patients studied in 1981 and evaluate the status of the ear, as well as long-term functional results.

The evolving treatment of necrotizing external otitis.

Necrotizing external otitis, or malignant external otitis, as initially described by Chandler, is a life-threatening Pseudomonas infection of the external auditory canal and skull base, which occurs most commonly in elderly diabetic patients. Historically, radical surgical intervention was the primary method of treatment. The treatment of choice has shifted during the past 20 years to aggressive systemic antibiotic therapy, with surgery reserved for those patients whose disease is resistant to medical therapy. Using this approach, 19 patients with necrotizing external otitis were treated at the Cleveland Clinic Foundation during the past 8 years. A 90% rate of cure was obtained. The diagnostic approach to patients suspected of having necrotizing external otitis, a classification scheme defining the extent of disease, delivery of systemic antibiotic therapy, indications for surgical intervention, and overall effectiveness of treatment are reviewed.

Clinical diagnosis of immune inner-ear disease.

The purpose of this study was to develop a high-risk clinical profile of patients with autoimmune (immune-mediated) inner-ear disease. The records of 52 patients diagnosed over the past 5 years were reviewed. Age, sex, bilateral versus unilateral involvement, otologic symptoms, concomitant systemic immune disease, and presenting clinical diagnoses were recorded. The presenting diagnoses were Cogan's syndrome, Meniere's syndrome, Dandy's syndrome without hearing loss, or progressive sensorineural hearing loss without dizziness. Because Cogan's and Dandy's syndromes were relatively uncommon, the typical high-risk clinical profile was a middle-aged patient (often female) with bilateral, asymmetric, progressive sensorineural hearing loss, with or without dizziness, and occasional systemic immune disease such as rheumatoid arthritis. When a more common clinical diagnosis cannot be reached in suspicious patients, immune laboratory tests should be obtained and a trial of immunotherapy offered. Positive test results and beneficial response to therapy support a presumptive diagnosis of immune inner-ear disease.