2相性頭位眼振を認めた頭部外傷例 A Case of Head Trauma with Positional Nystagmus with Secondary Phase
A 14-year-old boy visited our hospital with positional vertigo after head trauma. The color of his left eardrum was dark blue from bleeding in the middle ear and the external aural meatum was deformed. CT showed fracture of the left temporal bone. Various types of positional and positioning nystagmus were observed. In some head positions, positional nystagmus with a secondary phase was noted. The secondary phase in the opposite direction followed the first phase of positional nystagmus, while the patient remained in the same head position. This secondary phase of nystagmus was not observed after 10 days. Positional vertigo disappeared after 2 months.<BR>We speculated that the secondary phase of positional nystagmus was due to the movement of the debris in the semicircular canal or to short term adaptation of the central or peripheral vestibular system and that the secondary phase of nystagmus was in-creased by transient dysfunction of the central nervous system due to head trauma.
- Equilibrium research
Equilibrium research 56(6), 582-585, 1997-12-01
Japan Society for Equilibrium Research