Unbiased stereological quantification of neurons in the human vestibular ganglion

Vestibular ganglion (VG) neurons are bipolar neurons that relay peripheral vestibular information to the CNS. Neuron counts in normal humans provide a basis for quantitative studies on the effects of aging or pathological conditions in the audiovestibular systems. No prior study has employed unbiased stereological technique to count human VG neurons. This study used unbiased stereology in the form of the optical fractionator to estimate the total number of human VG neurons in archival temporal bone specimens. An average (+/- s.d.) of 27330+/-2593 neurons was found in specimens from five patients with no history of vestibular pathology. This result, a significant departure from results of past studies, provides the first unbiased baseline value to compare with future stereologically based studies on the human VG.