The other ear: findings and results in 1,800 bilateral stapedectomies.

OBJECTIVES: To determine the incidence of middle ear abnormalities in patients with bilateral otosclerosis, which could potentially affect successful stapedectomy, and the rates of success in these patients, including the chance of overclosure in the second ear. STUDY DESIGN: Retrospective case review of operative and audiologic records. SETTING: Private otology practice. PATIENTS: One thousand eight hundred patients underwent 3,600 primary stapedectomies for bilateral otosclerosis. INTERVENTION: Analysis of perioperative and follow-up audiograms with associated operative findings, including obliterative otosclerosis and solid footplates, dehiscent or overhanging facial nerve, narrow oval window niche, promontory overhang, and ossicular fixation or malformation. MAIN OUTCOME MEASURES: Audiologic stapedectomy success was determined as overclosure or closure of preoperative air-bone gap to less than 10 dB at 1 year or more of follow-up. RESULTS: The rate of finding any abnormality was 25%. Abnormalities present bilaterally were found in 135 patients (7%), with otosclerosis requiring an oval window drillout as the most common finding (41%), followed by dehiscent or overhanging facial nerves (25%). Success in patients with abnormalities was 78% overall, with bilateral overclosure in 40%. CONCLUSIONS: Abnormal middle ear findings during stapedectomy occur in a significant percentage of patients. Reasonable rates of success and overclosure can still be expected, but this is somewhat finding-specific. The predictive value of these findings, the associated rates of success with potential impact on surgical counseling, and planning for the "other ear" are discussed.

Analysis of the human neurofibromatosis type 2 gene promoter and its expression.

OBJECTIVE: It is hypothesized that transcriptional regulation plays an important role for neurofibromatosis type 2 (NF2) expression in Schwann cells and other cell types. The objective of this study is the isolation and characterization of the transcriptional regulatory elements of the NF2 gene. STUDY DESIGN AND SETTING: A bacterial artificial chromosome library and a partial genomic DNA library were used to isolate the human NF2 gene; NF2 promoter-luciferase constructs were generated, and promoter activities were assayed. This study was carried out in a molecular biology laboratory. RESULTS: A bacterial artificial chromosome clone with an approximately 100-kilobase insert containing nearly the entire human NF2 gene has been isolated. An additional 5' NF2 sequence has also been cloned. Transient transfection experiments demonstrate strong promoter activity from the NF2 5' flanking DNA. CONCLUSIONS: The NF2 gene is approximately 100 kilobases long. Both positive and negative regulatory elements are present in NF2 5' flanking regions. SIGNIFICANCE: Better understanding of the NF2 gene and its regulation will improve molecular diagnostics and ultimately treatment of patients with NF2.

Causes of unilateral sensorineural hearing loss screened by high-resolution fast spin echo magnetic resonance imaging: review of 1,070 consecutive cases.

OBJECTIVE: Evaluation of the ability of screening high-resolution, nonenhanced, fast spin echo (FSE) T2-weighted magnetic resonance imaging (MRI) of the internal auditory canal (IAC) and cerebellopontine angle (CPA) to detect nonacoustic schwannoma causes of unilateral sensorineural hearing loss (SNHL). FSE-MRI is equally sensitive in detecting acoustic (vestibular) schwannoma as gadolinium-enhanced MRI, but sensitivity to other causes of hearing loss is unknown. STUDY DESIGN: Retrospective review of screening FSE-MRI studies. SETTING: Academic otology/neurotology and neuroradiology practices. PATIENTS: There were 1,070 patients with unilateral SNHL who underwent radiologic screening for retrocochlear pathology. RESULTS: Normal findings were found in 944 cases. Typical (acoustic) vestibular schwannoma were found in 56 patients. Seventy additional lesions were identified: 27 CPA lesions, 29 inner ear lesions, and 12 intraaxial lesions including 9 infarctions, 1 multiple sclerosis case, 1 mesial temporal lobe sclerosis, and 1 colloid cyst. CONCLUSIONS: High-resolution T2 FSE-MRI of the IAC and CPA is a highly sensitive screening tool for unilateral SNHL, which can detect a variety of lesions in addition to vestibular schwannomas. To our knowledge in 2 years of follow-up in these patients screened for IAC/CPA lesions, no other lesions causing SNHL have been found. High-resolution FSE screening technique, used in conjunction with appropriate clinical prescreening and referral, can provide an equally sensitive method of evaluating unilateral SNHL compared to gadolinium-enhanced T1 MRI while reducing costs and providing distinct advantages in evaluating nonacoustic schwannoma causes of SNHL.

Preoperative antibiotics and steroids in vestibular schwannoma excision.

OBJECTIVE: To examine the benefits of preoperative admission for intravenous steroids and antibiotics for patients undergoing vestibular schwannoma excision. STUDY DESIGN: Retrospective cohort study. METHODS: One hundred twenty patients with pathologically confirmed vestibular schwannoma followed for at least 1 year after surgery were included. Sixty patients were assigned to the preoperative admission group and 60 patients to the same-day-admission surgery group. The preoperative admission group was given intravenous dexamethasone (0.1 mg/kg) and intravenous cefazolin (1 g) beginning 12 hours before surgery. The same-day-surgery group received the same dosage of medication beginning at induction of anesthesia. OUTCOMES: Facial nerve function, meningitis, and wound infection rates, duration of hospital stay, and readmission rates were examined. RESULTS: There was no statistical difference in facial nerve function between the groups when controlling for tumor size. Likewise, there was no difference in meningitis or wound infection rates in the groups. As expected, hospital stay was significantly reduced but readmission rates were not affected. CONCLUSIONS: There are no apparent facial nerve function or infection control benefits to 1-day preoperative admission for intravenous steroids and antibiotics for patients undergoing vestibular schwannoma excision.

Partial ossicular reconstruction in children: a review of 62 operations.

OBJECTIVE/HYPOTHESIS: The published experience and audiometric results with ossicular reconstruction in children are limited. To better understand the role of ossiculoplasty in children, audiometric results were examined for partial ossicular reconstructions performed on a pediatric population. STUDY DESIGN: Retrospective. METHODS: Sixty-two partial ossicular reconstructions performed on a pediatric population were reviewed for audiometric results, prosthesis extrusion rates, and mechanisms of failure at revision. Comparison of techniques and prosthesis types: porous polyethylene partial ossicular replacement prosthesis (POP), Schuring ossicle cup (SOC), and modified Robinson prosthesis (MRP) were also evaluated. Follow-up ranged from 6 to 72 months. RESULTS: Six-month hearing results showed postoperative airbone gaps less than or equal to 20 dB in 77% of cases. Successful results at 1 and 2 years were retained in 66% and 63% of cases, respectively. Results for POPs at 1 and 2 years were 78% and 89%. Results for SOCs at 1 and 2 years were 61% and 55%. The overall extrusion rate was approximately 3%. CONCLUSIONS: These results compare favorably with those from other, mostly adult, studies. Comparison of prosthesis types revealed generally stable long-term results with few significant differences. Success with ossiculoplasty in children can be obtained by applying the same principles and approach to ossicular reconstruction as used in adults. Ossicular reconstruction in children remains a secondary goal after establishing a safe, dry, and stable ear. A discussion of techniques and comparative literature review are presented.

Ultra high resolution nonenhanced fast spin echo magnetic resonance imaging: cost-effective screening for acoustic neuroma in patients with sudden sensorineural hearing loss.

The financial burden for the evaluation of patients for acoustic neuroma in an otolaryngology practice is substantial. Patients with sudden sensorineural hearing loss represent a portion of that population seen with unilateral, asymmetric auditory symptoms who require investigation for acoustic neuroma. For these patients, gadolinium-enhanced magnetic resonance imaging is the diagnostic gold standard. Auditory brain stem response testing has been used in the past as a screening test for acoustic neuroma, but its apparent sensitivity has fallen as the ability to image smaller acoustic neuromas has improved. Fast spin echo magnetic resonance imaging techniques without gadolinium have been shown to be as effective in the detection of acoustic neuroma as contrast-enhanced magnetic resonance imaging. Limited nonenhanced fast spin echo magnetic resonance imaging now provides an inexpensive alternative for high-resolution imaging of the internal auditory canal and cerebellopontine angle. Fast spin echo magnetic resonance imaging can now be done at a cost approximating auditory brain stem response testing while providing the anatomic information of contrast-enhanced magnetic resonance imaging. Cost analysis was done in the cases of 58 patients with sudden sensorineural hearing loss by comparing the costs for routine workup and screening of acoustic neuroma with the cost of fast spin echo magnetic resonance imaging with the use of screening protocols based on literature review. The potential cost savings of evaluating patients with sudden sensorineural hearing loss with fast spin echo magnetic resonance imaging for acoustic neuroma was substantial, with a 54% reduction in screening costs. In an era of medical economic scrutiny, fast spin echo magnetic resonance imaging has become the most cost-effective method to screen suspected cases of acoustic tumors at our institution by improving existing technology while reducing the cost of providing that technology and eliminating charges for impedance audiometry, auditory brain stem response testing, and contrast-enhanced magnetic resonance imaging.

Hemangiopericytoma of the masticator space.

Hemangiopericytomas are rare tumors of the head and neck. The benign presentation of this tumor belies its high local recurrence rate, local aggressiveness, and malignant potential. In view of these characteristics, workup to provide a diagnosis preoperatively is of significant importance. Diagnostic imaging is helpful in planning operative management, detecting metastases, and narrowing the list of differential diagnoses. However, because of the variety and lack of specificity of radiologic findings, it is generally difficult to provide a diagnosis. A history of a painless, slowly growing, otherwise asymptomatic mass, together with the radiologic findings of a vascular neoplasm, should enhance the suspicion of an HPC as a diagnosis. Hemangiopericytoma should be included in the differential diagnosis of any vascular soft tissue lesion presenting in the head and neck, and plans for surgical intervention should include the possibility of aggressive, wide local resection in order to adequately treat such a lesion should it be encountered.

Detection of viral DNA in endolymphatic sac tissue from Menière's disease patients.

Neurotropic viruses have been postulated to play a role in the development of Menière's disease (MD). The purpose of this study was to evaluate the endolymphatic sacs of patients undergoing surgery for MD in a single-blind study for evidence of herpes simplex virus (HSV), varicella zoster (VZ), or cytomegalovirus (CMV) DNA. Polymerase chain reaction (PCR) was used as the method of detection because of its sensitivity, specificity, and applicability to fresh, as well as fixed tissues. Twenty-two patients with MD and 11 control patients with vestibular schwannomas had a portion of the endolymphatic sac removed at the time of surgery. The specimens were then evaluated for herpes simplex type and 2, varicella zoster, and cytomegalovirus DNA. Herpes simplex virus DNA was detected in 2 of the 22 extracts from the endolymphatic sacs obtained from patients with MD. There was no evidence of a positive signal obtained with any of the other viral DNA probes when PCR was performed on the control tissue extracts or the other MD tissue extracts. These results do not demonstrate a significant difference and do not statistically support the postulate that ongoing viral infection in the endolymphatic sac is a frequent factor in the development of Menière's disease.

Effect of intranasal inoculation of Streptococcus pneumoniae on the structure of the surface carbohydrates of the chinchilla eustachian tube and middle ear mucosa.

The changes in the cell surface carbohydrates of the eustachian tube (ET) and middle ear subsequent to the intranasal (i.n.) inoculation of Streptococcus pneumoniae (Spn) type 6A were studied in the chinchilla model of otitis media (OM) using a lectin histochemical technique with six different lectins (SNA, WGA, Succ WGA, BSL II, PNA, ECL). The labeling pattern revealed not only the removal of the terminal sialic acid, but also exposure of N-acetylglucosamine (GlcNAc), a component of the trisaccharide receptor for Spn previously identified on human pharyngeal cells. The removal of sialic acid residues progressed from the nasopharyngeal to the tympanic orifice and was most pronounced in those animals from which Spn could be isolated from the middle ear. Our data indicate an alteration of the normal lectin labeling pattern and exposure of GlcNAc restricted mainly to the roof and neck portion, along the course of the eustachian tube. Exposure of part or all of a Spn adherence receptor structure by the pneumococcal enzymes, may facilitate colonization, invasion of the middle ear, and induction of OM.

Analysis of frequency of pulmonary atelectasis in patients undergoing pectoralis major musculocutaneous flap reconstruction.

The incidence of pulmonary atelectasis following head and neck surgery is not well reported. This study retrospectively evaluated the incidence of pulmonary atelectasis in 161 head and neck cancer patients, with 152 being evaluable. There were 90 patients evaluated following pectoralis musculocutaneous flap reconstruction with their effective flap size and 71 nonflap patients as a control group. Clinical findings were correlated to radiographic scores. Of pectoralis musculocutaneous flap patients screened for preexisting pulmonary disease (PEPD), nine of 45 (20%) demonstrated pulmonary atelectasis in the first 24 hours compared with 10 of 39 or 25.6% nonflap controls. Major pulmonary atelectasis was not found in the pectoralis musculocutaneous flap patients by scoring criteria, and in only one of 39 (2.6%) nonflap patients. In flaps larger than 40 cm2, the incidence was eight of 37 (21.6%), with no major pulmonary atelectasis noted. Only one of nine (11.1%) patients with radiographic pulmonary atelectasis exhibited clinical symptoms (three of 10 or 30% control). In patients with PEPD and pectoralis musculocutaneous flaps, 22 of 45 (48.9%) had evidence of pulmonary atelectasis in contrast to 13 of 32 or 40.6% controls. There were two of 45 (4.4%) who had major pulmonary atelectasis with zero of 32 in the nonflap group. For flaps larger than 40 cm2, the incidence was 19 of 39 (48.7%) with two of 39 (5.1%) scored as major pulmonary atelectasis. The clinical correlation for this group and the major pulmonary atelectasis group was each approximately 50% compared to 15.4% for nonflap patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Modeling adenovirus type 1-induced otitis media in the chinchilla: effect on ciliary activity and fluid transport function of eustachian tube mucosal epithelium.

Previous studies have shown that viral upper respiratory tract (URT) infection predisposes to the development of bacterial otitis media (OM). The mechanisms underlying this phenomenon have been well defined for influenza A virus in the chinchilla model of experimental OM but have not been for adenovirus because of the heretofore lack of an appropriate model. In this study, chinchillas were inoculated intranasally or transbullarly with type 1 adenovirus to assess whether or not the chinchilla could serve as a suitable model for future investigation of adenovirus predisposition to bacterial OM. Data indicated that the chinchilla readily supported an active infection by and responded serologically to this agent and that route of inoculation markedly influenced otoscopic findings, elicitation of middle ear fluids, onset and location of histopathology, and progression of disease. The time course of disease onset and recovery and an assessment of the effect of this virus isolate on the mucosal epithelial integrity and on both the ciliary activity and transport function of the eustachian tube epithelium for both routes of inoculation are presented.