迷路性固視機能検査法に関する研究 : 地磁気センサによる基準範囲 [in Japanese] Active Head Oscillation Vestibular Testing with a Terrestrial Magnetism Sensor : Reference lntervals in Healthy Subjects [in Japanese]
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The purpose of this study was to determine reference intervals of the characteristics of the visual-vestibuloocular reflex in healthy subjects.<BR>Head and eye movements during active head oscillation were examined. The head was oscillated in the horizontal (H) and vertical (V) planes, and head movements were recorded with a terrestrial magnetism sensor. Eye movements were recorded by an elec-tronystagmographic technique. The examination was performed under the following 2 conditions: a) visual fixation on an earth-fixed target in the light (test for visual-vestibuloocular reflex, VVOR), and b) image fixation on an earth-fixed target in the dark (test for vestibuloocular reflex, VOR). The data were stored on a floppy disc in a microcomputer. From the stored data, transfer function was calculated with head movements as input and eye movements as output in a specially designed program.<BR>Five healthy adults were tested. From the data obtained, the mean and the standard deviation were calculated.<BR>Results<BR>a) VVOR test:<BR>(1)The breakpoint frequencies were 3.3±0.5 Hz (H) and 2.2±0.4 Hz (V).<BR>(2)The frequency ranges of 180°±10° were 0.2±0.1-0.9±0.2 Hz (H) and 0.2±0.2-0.6±0.6 Hz (V).<BR>b) VOR test<BR>(1)The gains at 0.1 Hz were-5±2 dB (H) and-3±2 dB (V).<BR>(2)The slopes of the gain enhancement were 6±2 dB/dec (H) and 4 ± 4 dB/dec (V).<BR>(3)The frequency ranges of 180°±10° were 0.1±0.1-0.8±0.2 Hz (H) and 0.2±0.1-0.6±0.4 Hz (V).<BR>The mean±the standard deviation×2 are presented as reference intervals.
- Equilibrium Research
Equilibrium Research 54(2), 225-235, 1995-04-01
Japan Society for Equilibrium Research