The minimum speech test battery in profound unilateral hearing loss.

OBJECTIVE: Individuals with monaural hearing experience disadvantages compared with normal hearing counterparts because of the loss of the head shadow effect, the squelch effect, and binaural summation. In this study the Minimum Speech Test Battery (MSTB), a battery designed to document word recognition in bilaterally hearing impaired cochlear implant candidates, was administered to unilaterally hearing-impaired and normal hearing subjects to study its possible use in measuring hearing difficulty in monaural subjects. STUDY DESIGN: Repeated measures design with the MSTB administered in sound-field in a sound-isolated booth in 1) quiet; 2) speech toward good ear, noise (+10 dB S/N) toward impaired ear; 3) speech toward impaired ear, noise toward good ear; and 4) bilateral speech and noise. SETTING: Academic otologic practice. PATIENTS: Ten adults with normal hearing and 10 adults with normal or near-normal hearing in one ear and profound hearing loss in the contralateral ear. MAIN OUTCOME MEASURES: The MSTB, composed of the Consonant-Nucleus-Consonant (CNC) test and the Hearing In Noise Test (HINT). RESULTS: As expected, performance differences between the groups were not found in quiet conditions. Analysis of variance and regression analysis confirmed that the impaired group performed significantly worse than control subjects on HINT testing when noise was directed toward the good ear. Analysis of variance and regression analysis confirmed that the impaired group performed significantly worse than control subjects on CNC testing when noise was directed toward the good ear and in bilateral noise. CONCLUSIONS: The MSTB may be useful in measuring the hearing difficulty of patients with monaural hearing.

Mastoid oscillation in canalith repositioning for paroxysmal positional vertigo.

OBJECTIVE: The canalith repositioning procedure (CRP) was developed to treat paroxysmal positional vertigo (PPV). Successful CRP results in cessation of PPV and positional nystagmus. Mastoid oscillation (MO) has been advocated to enhance the efficacy of CRP. The authors sought to objectively determine the effect of MO on CRP. STUDY DESIGN: Retrospective review. SETTING: Ambulatory referral center. PATIENTS: Patients with PPV seen from 1993 through 1999 (N = 168). INTERVENTIONS: Canalith repositioning procedure performed without MO (n = 104) and performed with MO (n = 64). MAIN OUTCOME MEASURE: Presence or absence of nystagmus on Dix-Hallpike testing 6 weeks after CRP. RESULTS: Eighty-four percent of patients treated with MO had resolution, and 16% had persistent nystagmus. Seventy-three percent of patients without MO had resolution, and 27% had persistent nystagmus. Although suggesting a trend, the difference did not reach the level of significance (p = 0.151). CONCLUSIONS: Mastoid oscillation does not significantly enhance the efficacy of the CRP.

Cochlear implantation in sudden bilateral sensorineural hearing loss.

Although 1-4% of all cases of sudden sensorineural hearing loss (SSHL) are bilateral, all such patients reported to date have experienced significant recovery of hearing in at least one ear. We report a case of profound, bilateral idiopathic SSHL without recovery which was treated with cochlear implantation; the first such report to our knowledge. The patient achieved open-set spondee recognition. Individuals with sudden bilateral hearing loss in whom treatable causes have been eliminated may benefit from cochlear implantation.

Measurement of facial movement with computer software.

OBJECTIVE: To adapt desktop computer software to objectively grade facial movement. DESIGN: The criteria of the facial nerve grading system by House and Brackmann, the current "gold standard," are prone to ambiguous interpretation. Proposed objective grading systems compare the movement of points on each side of the face or use subtraction and thresholding of digitized images of the face to yield images that represent moving areas of the face. The movement of a point on the face and the area of motion determined by digital subtraction were compared during an increasing smile in healthy subjects. The Nottingham system (calculated using measurement of the movement of 4 points on the face) using desktop computer software (Adobe Photoshop 3.0, Adobe Systems Inc, Mountain View, Calif) to measure movement of the points was compared with the system by House and Brackmann. The computer software was used to subtract digitized images and derive a facial movement score, which was compared with the scores of the systems by Nottingham and House and Brackmann. SETTING: Academic otologic practice. STUDY PARTICIPANTS: Nine patients with varying degrees of facial nerve disability and 7 individuals with normal facial nerve function. RESULTS: The movement of the oral commissure compared with the apparent area of movement of the face determined by digital subtraction had high intersubject variability. In patients with facial weakness, the Nottingham score had a correlation coefficient of -0.97 compared with the House and Brackmann grade, and the digital subtraction score had a correlation coefficient of -0.62 (paired Student t test). CONCLUSIONS: The desktop computer software can be used to calculate the Nottingham score. Digital subtraction as a measure of facial function warrants further study.

Sudden sensorineural hearing loss following nonotologic, noncardiopulmonary bypass surgery.

OBJECTIVES: To report 3 cases of sudden sensorineural hearing loss (SSHL) following nonotologic surgery in which cardiopulmonary bypass (CPB) surgery was not involved and to review reports in the literature of similar cases. DATA SOURCES: Clinical records and MEDLINE and Healthstar databases. STUDY SELECTION: Reports in the world literature of cases of SSHL following nonotologic, non-CPB surgery. DATA SYNTHESIS: While said to be more common after CPB surgery, fewer than 20 cases of SSHL following non-otologic, non-CPB surgery have been reported. A number of proposed causes of SSHL temporally related to non-otologic, non-CPB surgery have been theorized; however, the true cause is unknown. This report presents 3 cases of SSHL following nonotologic, non-CPB surgery. Two patients had profound unilateral loss; 1 had moderate bilateral loss. None of the patients demonstrated recovery despite diuretic and prednisone therapy; in approximately 30% of the cases reported to date, the patients experienced significant improvement. CONCLUSIONS: Sudden sensorineural hearing loss following nonotologic, non-CPB surgery is rare, and its cause remains unknown. The scarcity of reports of SSHL following nonotologic, non-CPB surgery raises the possibility that the apparent association may be spurious.

Idiopathic bilateral vestibular loss.

We describe the clinical and laboratory features of 13 patients with bilateral loss of peripheral vestibular sensitivity of no known cause. In the office, screening for this condition was possible using illegible e-testing and examination of the patient for refixation saccades after brisk head movements while attempting visual fixation. Diagnosis was confirmed by bilaterally reduced caloric responses (< 20 degrees/second on all 4 caloric irrigations) and abnormally low gain of the vestibulo-ocular reflex on rotational chair testing. The mean age of the patients was 68 years. We noted two patterns of symptom onset: onset associated with vertigo (10 patients) and insidious progressive disequilibrium not associated with vertigo (3 patients). Only 38% of the patients complained of subjective oscillopsia. The subjects performed poorly on platform posturography, particularly when deprived of visual and somatosensory feedback. When associated with vertigo, bilateral vestibular loss may be the result of bilateral sequential vestibular neuritis; when not associated with vertigo, disequilibrium may be caused by slow, symmetrical loss of peripheral function as a result of aging. Although the subjects in this report were elderly, idiopathic bilateral vestibular loss has been reported in patients of all ages.

Meatal facial nerve decompression in acoustic neuroma resection.

Delayed facial palsy occurs after approximately 15% of acoustic neuroma resections. Whereas in most cases facial nerve function recovers satisfactorily, in about 12% of cases delayed facial palsy may have a poor functional recovery. The fate of facial nerve function was studied in 55 consecutive translabyrinthine acoustic neuroma resections, 23 of whom underwent meatal facial nerve decompression (MFND) at the time of tumor resection. The facial nerve results also were reviewed in 19 middle cranial fossa resections, of whom 14 underwent MFND. There was a bimodal distribution of the delayed palsies, with one group having the onset of palsy within hours to 2 days after surgery and the second group having onset of palsy up to 17 days after surgery. The poorest recoveries were seen in the first group. Although the effect was not statistically significant due to the small sample size, the chance of facial weakness in patients who underwent MFND after translabyrinthine surgery was about 40% less than in those who did not undergo decompression. The apparent protective effect of MFND was increased when the confounding factors of tumor size and degree of resection were taken into account, although the effect was not statistically significant. The duration of palsy was shorter and ultimate recovery better among the patients who underwent facial nerve decompression than in those who did not. Of the translabyrinthine patients who underwent MFND, 100% had House-Brackmann grade I-II function at 2 years, whereas 87% of patients who did not have MFND had grade I-II function and 13% had grade III-IV function. Without MFND, 57% of translabyrinthine patients whose onset of facial palsy was within 2 days of surgery had grade III-IV facial nerve function.

Posterior semicircular canal occlusion for benign paroxysmal positional vertigo--CO2 laser-assisted technique: preliminary results.

Benign paroxysmal positional vertigo (BPPV) is a common vestibular end-organ disorder that in the majority of patients resolves with conservative management. In the occasional patient who has unremitting BPPV despite conservative treatment, posterior semicircular canal occlusion (PCO) may be effective in eliminating symptoms. In an attempt to minimize the risk of hearing loss, a modified procedure was developed that uses the CO2 laser to shrink the membranous vestibular posterior semicircular canal prior to mechanically plugging the canal. Preliminary results of this CO2 laser-assisted occlusion technique used in four patients are presented.

Carcinoma metastatic to both cerebellopontine angles masquerading as acoustic neuromas.

Metastases to the cerebellopontine angles (CPAs) are rare. Typically, the clinical course is one of rapid onset and progression of crarial nerve deficits. The clinical presentation and course of carcinoma metastatic to the CPAs are reviewed. We report a case of bilateral CPA metastases with a radiographic appearance similar to neurofibromatosis type 2 presenting with rapidly progressive bilateral hearing loss followed by unilateral facial nerve palsy.

Giant intradiploic epidermoid cyst of greater sphenoid wing causing unilateral proptosis and optic nerve compression.

Epidermoids are cystic tumors that arise from aberrant epidermal cells. Intradiploic epidermoids are relatively rare tumors that occur in all bones of the calvarium, temporal and sphenoid bones, paranasal sinuses, and maxilla. We report the case of an intradiploic epidermoid of the sphenoid wing causing severe proptosis and visual loss. Theories of embryogenesis and pathophysiology are discussed.

Visually-induced adaptive plasticity in the human vestibulo-ocular reflex.

The vestibulo-ocular reflex (VOR) is under adaptive control which corrects VOR performance when visual-vestibular mismatch arises during head movements. However, the dynamic characteristics of VOR adaptive plasticity remain controversial. In this study, eye movements (coil technique) were recorded from normal human subjects during sinusoidal rotations in darkness before and after 8 h. of adaptation to 2X binocular lenses. The VOR was studied at 7 frequencies between 0.025 and 4.0 Hz at 50 degrees/s peak head velocity (less for 2.5-4 Hz). For 0.025 and 0.25 Hz, the VOR was tested at 4 peak head velocities between 50 and 300 degrees/s. Before 2X lens adaptation, VOR gain was around 0.9 at 2.5-4.0 Hz and dropped gradually with decreasing frequency to under 0.6 at 0.025 Hz. Phase showed a small lead at the highest frequencies which declined to 0 degree as frequency decreased to 0.5-0.25 Hz, but then rose to 14 degrees by 0.025 Hz. VOR gain was independent of head velocity in the range 50-300 degrees/s at both 0.025 and 0.25 Hz. However, Phase lead rose with increasing head velocity, more so at 0.025 than at 0.25 Hz. After 2X lens adaptation, gain rose across the frequency bandwidth. However, the proportional gain enhancement was frequency dependent; it was greatest at 0.025 Hz (44%), and declined with increasing frequency to reach a minimum at 4 Hz (19%). Phase lead increased after 2X lens adaptation at lower frequencies, but decreased at higher frequencies. New velocity-dependent gain nonlinearities also developed which were not present prior to adaptation; gain declined as peak head velocity increased from 50 to 300 degrees/s at both 0.025 (23% drop) and 0.25 Hz (15% drop). This may suggest an amplitude-dependent limitation in VOR adaptive plasticity. Results indicate both frequency and amplitude dependent nonlinearities in human VOR response dynamics before and after adaptive gain recalibration.

The primate vestibulo-ocular reflex during combined linear and angular head motion.

The squirrel monkey vestibulo-ocular reflex (VOR) was studied in darkness during Earth-horizontal rotation over a frequency range, 0.01-4 Hz, with the head positioned both centrally and displaced radially relative to the axis of rotation. With the head centered, the canal-mediated angular VOR (AVOR) was recorded in isolation. However, with the head placed eccentrically, otolith-mediated linear VOR (LVOR) components interact with the AVOR to yield a combined AVOR-LVOR response. The plane of the ocular response could be manipulated by placing the head in different orientations relative to gravity (i.e. upright or nose-up). When the head was upright and centered, the horizontal AVOR was recorded. Comparisons between eye and head angular velocity showed that gain (pk eye/pk head velocity) was nearly flat, averaging 0.83, across the frequency range. Phase (difference in degrees between eye and head velocity, shifted 180 degrees by convention) was near 0 degrees, except at frequencies below 0.1 Hz where phase leads were seen. When the head was displaced eccentrically and in the nose-out position (facing away from the axis of rotation), gain rose above that of the AVOR alone. The enhancement was progressive with increasing frequency, but only for frequencies above 0.25 Hz. When the subject was turned nose-in, gain declined relative to the AVOR alone, and in a similar frequency-dependent fashion. These results are consistent with the notion that nose-out and nose-in responses to eccentric rotation represent a combined influence of the horizontal AVOR and LVOR, the latter driven by inter-aural tangential acceleration. To further evaluate this possibility, eccentric rotation was also used to assess the LVOR in isolation. With the head in the nose-up orientation, the AVOR was shifted into the head's roll plane and generated torsional ocular responses. With the head centered over the axis of rotation, no systematic horizontal responses were observed. However, when the head was displaced eccentrically and placed in the head-out and head-in positions, horizontal ocular responses were recorded which were proportional to head eccentricity and were of appropriate polarity to presume that they represented the inter-aural LVOR activated by inter-aural tangential acceleration. Response gain rose with increasing frequency, as did tangential acceleration. The LVOR in its resting state in darkness could be characterized by an average sensitivity of 40.3 degrees/s/g (g = 9.81 m/s2).(ABSTRACT TRUNCATED AT 400 WORDS)

Selection of monoclonal antibody to hCG which localizes in human choriocarcinoma growing in the Syrian hamster cheek pouch.

Six different monoclonal antibodies (MAbs) to human chorionic gonadotropin (hCG) were evaluated for radioimmunodetection in Golden Syrian Hamsters bearing a human choriocarcinoma in the cheek pouch (188-516 mIU of hCG/g). The affinity of three antibodies when determined were high and five of the antibodies were of IgG1 subclass. After i.v. injection of Staphylococcus Protein A (SPA) affinity purified radioiodinated antibodies, tissue distribution studies demonstrated that antibody 061 had higher target-to-nontarget ratios than the other five antibodies. The mean tumor:muscle ratio of 131I-MAb 061 was 27.5 in four animals, where the mean tumor:muscle ratio of four animals injected with 131I-labeled control monoclonal IgG1 Kappa from MOPC-21 murine myeloma (MOPC-21) was only 2.2. Sharp images of the cheek pouch tumor were obtained at five days following a tracer dose of 131I-061 MAb, but not with the same dose of a 131I-MOPC-21.