Effects on cervical vestibular-evoked myogenic potentials of four clinically used head and neck measurement positions in healthy subjects

The most reliable head and neck position for cervical vestibular-evoked myogenic potentials (cVEMPs) measurements yet to be determined.To assess how four body positions used during clinical recordings of cVEMPs affect cVEMP parameters.cVEMPs of 10 healthy subjects (26-50 years old) were recorded in four body positions:Mean background sternocleidomastoid muscle (SCM) electrical activity was significantly higher in positions C and D than in positions A and B. The latencies of p13 and n23 differed significantly among the four positions. Raw p13-n23 complex amplitude was significantly greater in positions C and D than in A and B. These differences were reduced when amplitudes were corrected by SCM activity. For positions A and B, one and two subjects, respectively, had an abnormal raw asymmetry ratio (AR). After correction, all subjects had normal ARs in all positions.Body positions in which the head is elevated produce a quicker and larger cVEMP response compared to positions in which the head is not elevated. The difference in ARs among positions can be ignored as long as the correction is made.