Search

The device of subjective visual vertical (SVV) was made to test the gravity orientation of subjects visual.The normative value was established firstly in the right, left and both eyes respectively. Then the test was applied to evaluate the function of otolith function (utricular function) in normal adult subjects and examined the SVV in some patients suffered from acute unilateral vestibulopathy.The difference of the SVV among right, left and both eyes was not significant and the normative value was lower than +/- 2 degrees. No matter one eye or both eyes, SVV had the tendency to lateraliseze to the right.The SVV is a reliable choice to test the otolith vestibulopathy, which is at least suitable for acute phase. The bilateral eyes open mode is recommended to test the subjects suspected of utricuar dysfunction.

To investigate the occurrence, genetic inheritance, and hearing loss conditions of large vestibular aqueduct syndrome (LVAS), and to measure the width of external aperture of vestibular aqueduct (VA) of LVAS, and to analyze the relationship between the hearing loss and the width of external aperture.A retrospective review was conducted by the history, auditory, and vestibular function examinations in 95 patients (190 ears) of LVAS. The width of VA was measured by CT scanning criterion of each LVAS patients in the past 10 years (from 1992 to 2002).In 95 patients, there were male 65 cases and female 30 cases. The male cases was more than the females by a ratio of 2.2:1. Twelve cases (12.6%) would have familial genetic history. The average of the consult age was 7.6 years (range from 1.2 to 39 years). The most patients were misdiagnosed, the hearing deterioration originated from mild head trauma in 21 cases (22.1%), the hearing loss after common cold in 13 cases (13.6%). Nine cases (9.5%) misdiagnosed as sudden hearing loss, 5 cases (5.3%) as ototoxic hearing loss of Aminoglycoside antibiotic. The profound hearing loss was found in 172 ears (92.4%). The average width of external aperture of LVAS was 7.5 mm +/- 1.2 mm (mean +/- s, 77 cases, 154 ears). The level of hearing loss did not proportional to the width of VA. The hearing impairment could be derived from protein-rich endolymph refluxed into the cochlear and vestibule.The LVAS is distinct clinical entity characterized by fluctuate and progressive SNHL. The diagnosis depends upon the CT scan and MR image. If the hearing fluctuated and subsequently improved, the children were kept under conservation treatment. If the significantly decreased of hearing effected school performance, the cochlear implant might be considered.