The sinusoidal harmonic acceleration test in vestibular disorders. Comparative study with caloric test results.
Sinusoidal harmonic acceleration test (SHA) was performed on 89 patients with peripheral vestibular disorders. The results of SHA were compared with that of the alternate bilateral caloric test. The patients were classified into 3 groups according to the degree of asymmetry of the caloric response (CP). In the lowest frequency rotation (0.01 Hz), the phase lags for all 3 groups were smaller than the normals. The phase lags tended to approach the normal value as the frequency of rotation increased, resulting in a phase lag curve of typical peripheral type. Even subjects without CP revealed a decreased phase lag. This indicates that the SHA at low frequencies is more sensitive than the caloric test for diagnosing a vestibular lesion. In the 0.02 Hz range, the phase lag of the patient without CP were close to the normals, however, the phase lags of the patients with severe CP were smaller than the normals. This suggests that SHA to 0.02 Hz should be given more credence, since it appears to be critical for diagnosing more extensive lesions.
Suzuki
M
M
Department of Otolaryngology, Hiroshima University, School of Medicine, Japan.
Pulec
J L
JL
Smith
J C
JC
D000054:Acceleration; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002150:Caloric Tests; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012399:Rotation; D015837:Vestibular Diseases / Q000175:diagnosis*; D014724:Vestibular Function Tests / Q000379:methods*