Seasickness
Conditions
Brief summary
Participants were selected from the military navy crewmembers prior to commencing of active sailing. A vestibular time constant was calculated based on velocity step testing on a rotatory chair at baseline, 3 months and 6 month following active sailing duty. A seasickness questionnaire (WIKER) was completed during follow-up visits. study participants were divided to three groups based on WIKER score - susceptible , non-susceptible and habituating. Vestibular time constant was compared between study groups.
Interventions
DIAGNOSTIC_TESTrotatory chair testing in a velocity step protocol.
Tc was evaluated by the rotational velocity step test using the OtoaccessTM interface (Interacoustics Nydiag 200, Middlefart, Denmark). Subjects were seated on the rotatory chair wearing videonystagmography goggles with their heads supported and tilted 30° forward, thus bringing the horizontal semicircular canals plane perpendicular to the axis of rotation. Standard videonystagmography techniques were employed to record eye-movements. Subsequent to eye movements' calibration, the chair was accelerated about the yaw axis at 30°/sec2 to a maximal velocity of 90°/sec, followed by rotation at a constant velocity. After 57 seconds of constant velocity rotation, the chair was decelerated to zero velocity at 30°/sec2. The described velocity step was conducted both clockwise and counter-clockwise, giving a total run time of 4 minutes.
Sponsors
Medical Corps, Israel Defense Force
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
18 Years to 20 Years
Healthy volunteers
Yes
Inclusion criteria
* healthy male Navy sailors in basic training
Exclusion criteria
* History of hearing loss * Otoscopic findings of ear pathology * An implanted electrode * A finding of vestibulopathy upon otoneurological examination - * Discontinuation of active sailing for any reason during study follow-up * Withdrawal of informed consent.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 6 month follow up vestibular time constant measurement. | 6 months | vestibular time constant in seconds is the measurement of decline in maximal slow phase velocity of eye movement during nystagmus to 37% of initial value produced by abrupt acceleration and declarations in a rotatory chair - step velocity protocol. |
Countries
Israel
Outcome results
None listed