Diagnosis of Otolith and Semicircular Canal Lesions by Galvanic Nystagmus and Spinal Reflexes

概要

論文の詳細を見る
Galvanic nystagmus and spinal reflexes were investigated in normal subjects and patients with labyrinthine disturbances.Methods: Galvanic stimulation was performed by the biaural-bipolar method. Galvanic nystagmus was induced by application of a direct current of 3mA for 60sec. Galvanic spinal reflexes were observed with sway of the head and the body center of gravity as well as soleus muscle activities induced by the application of a direct current of 1mA for 3 or 6sec. The sway of the body center of gravity indicated an initial response (IR) toward the cathode side followed by a deviation response (DR) toward the anode side.Results: A. Among the patients who did not respond to rotatory and caloric labyrinthine stimulation, one showed no galvanic nystagmus but normal galvanic spinal reflexes. In another patient, on the contrary, galvanic nystagmus was induced normally, while galvanic body sway was reduced. Clinical symptoms and other balance tests, such as the standing test, suggest that galvanic nystagmus is mainly a reaction of the semicircular canal system while spinal reflexes are mainly a reaction of the otolithic system.B. The results of the galvanic spinal reflex test in 22 patients with unilateral or bilateral labyrinthine disturbances were classified from A to C. In type A, IR and DR were normal. In type B, IR was normal but DR was absent or reduced. Type C showed no IR, and DR was absent or reduced. Galvanic spinal reflexes in normal subjects suggest that IR is induced by action potentials of the vestibular nerve, which occur as the electric current is turned on, while deviation responses are due to the electrotonic effect of the galvanic current on the resting discharges of the vestibular nerve. This interpretation enabled us to localize lesions in the otolithic system.
耳鼻咽喉科臨床学会の論文

Diagnosis of Otolith and Semicircular Canal Lesions by Galvanic Nystagmus and Spinal Reflexes

スポンサーリンク

概要

著者

関連論文

スポンサーリンク