2004 Volume 97 Issue 12 Pages 1053-1058
Three cases of central positional vertigo (central PV) in young patients were reported. The first case had combined torsional and horizontal nystagmus to the right in a head-hanging position. The nystagmus lacked latency and did not diminish easily. Magnetic resonance imaging (MRI) scan showed a tumor in the medulla, which was histologically diagnosed as astrocytoma. The second case had very weak apogeotropic nystagmus with torsional and horizontal components in a head-hanging-left position. The nystagmus diminished after 3 or 4 beats, but was easily reproduced. MRI showed arteriovenous malformation in the vermis. The third case showed positional nystagmus that resembled benign paroxysmal positional vertigo (BPPV), but did not respond to vestibular rehabilitation therapy. MRI showed multiple tumors in the cerebellum, which were histologically diagnosed as neuroblastoma. Close examination of nystagmus based on an understanding of BPPV is the most useful clue for a correct diagnosis. However, even if the nystagmus is consistent with that of BPPV on initial assessment, central PV cannot be excluded, and careful follow-up is necessary until both objective and subjective symptoms diminish.