Peripheral vestibular disorder (PVD) is serious and common. Clinically, giving an accurate diagnosis of PVD can be challenging. Vestibular evoked myogenic potential (VEMP) is an objective test to evaluate the integrity of vestibular organs, particularly saccule and/or inferior vestibular nerve. This study was performed to determine the sensitivity and specificity of VEMP using different stimuli. Fourty normal and 65 PVD subjects who fulfilled the inclusion criteria were recruited. While sitting comfortably, VEMP waveforms were recorded with active electrode on sternocleidomastoid muscle and negative electrode on upper forehead. Tone bursts (500, 750 and 1000 Hz) were delivered via headphones at 90 dBnHL and 5/s presentation rate. VEMP parameters for each stimulus (amplitude and latency of P1 and N1 peak) were analyzed accordingly. Receiver operating characteristic (ROC) was performed to determine the sensitivity and specificity of VEMP at different test frequencies. N1 amplitude of 750 Hz stimulus produced the most ideal sensitivity (65% on right and 63% on left) and specificity (83% on right and 78% on left). The importance of using a few tone bursts in VEMP test in order to minimize the false negative in cases might be encountered in clinics as the certain tone burst had inadequate sensitivity in detecting PVD cases. The 750 Hz stimulus produced the most ideal VEMP with adequate values of sensitivity and specificity, at least in this study.
Vestibulocochlear Nerve Diseases

Objective: To present 3 cases of Möbius sequence exposed in utero to misoprostol and discuss their clinical presentations, etiopathogenesis, and management. Methods: Medical records of 3 patients with Möbius sequence and prenatal exposure to misoprostol were reviewed. Clinical findings were compared with those reported in the literature. Results: Lack of facial-muscle movement, lagophthalmos with secondary exposure keratitis, decreased ability to crease forehead, and shallow nasolabial fold imply facial-nerve dysfunction. Small- and large-angle esotropia and apparent orthotropia with abduction limitation showed varying degrees of abducens nerve involvement. Two patients had early prenatal exposure to misoprostol during the first 3 months of gestation. Conclusion A history of misoprostol exposure should be routinely elicited from parents of children with Möbius sequence. Associated deficiencies in Möbius sequence and its variants require a multidisciplinary approach.
Abducens Nerve Vestibulocochlear Nerve Paralysis

Neurovascular compression syndrome of the eighth cranial nerve is characterized by recurrent audiologic and vestibular symptoms. The clinical presentation is the most important for diagnosing neurovascular compression syndrome of the eighth cranial nerve. This review describes the pathophysiology, diagnosis and treatment of neurovascular compression syndrome of the eighth cranial nerve.
Diagnosis ; Nerve Compression Syndromes ; Vertigo ; Vestibulocochlear Nerve*

Audiometry ; Humans ; Vestibulocochlear Nerve Diseases ; etiology ; physiopathology

A narrow internal auditory canal(IAC) is a malformation of the temporal bone, which is defined as IAC diameter of only 1-2mm in high resolution computed tomography(HRCT). This syndrome is known to be caused by aplasia or hypoplasia of the vestibulocochlear nerve. We present a case of unilateral narrow IAC which was diagnosed by HRCT. The aplasia of vestibulocochlear nerve was confirmed using MRI with parasagittal reconstruction images. The IAC was composed of two separate canals, one of which had facial nerve and the other an empty space by aplasia of the vestibulocochlear nerve.
Facial Nerve ; Magnetic Resonance Imaging ; Temporal Bone ; Vestibulocochlear Nerve

Acclimatization ; Dizziness ; rehabilitation ; therapy ; Humans ; Vestibulocochlear Nerve ; physiology

Cochlear Implantation ; Cochlear Implants ; Humans ; Vestibulocochlear Nerve Diseases

OBJECTIVETo analyze the clinical diagnosis of auditory neuropathy by retrospective review of the articles published in Chinese Journals in the past 10 years.

METHODSThe key word of "auditory neuropathy" was used to search all of the articles published in Chinese Journals by the Chinese Bio-medicine Literature Data Base and Chinese Journal Net from 1995 to 2004. The selected subjects of auditory function examination, diagnosis standards were analyzed, respectively.

RESULTSForty-two articles were collected, and 23 articles were clinical researches and case reports. There were 573 patients (1146 ears) in all series, and 480 ears (42%) were accords with the standards of diagnosis of auditory neuropathy. Others were accompanied by cochlea, brain stem and peripheral nerve disorders.

CONCLUSIONThe clinical manifestation and hearing examination on auditory neuropathy in Chinese journal literatures is inconsistent with the diagnosis standards, moreover, it is necessary to further explore the pathological location and unify the diagnosis standards of auditory neuropathy.

Hearing Loss, Central ; genetics ; Humans ; Vestibulocochlear Nerve Diseases

Hair Cells, Auditory, Inner ; Humans ; Synapses ; Vestibulocochlear Nerve Diseases