Seasickness Susceptability and Vestibular Time Constant

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.

Study Overview

• Status: Completed
• Conditions: Seasickness
• Intervention / Treatment: Diagnostic test: rotatory chair testing in a velocity step protocol.

• Study Type: Interventional
• Enrollment (Actual): 67
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Israel
  • Haifa, Israel, 2705335
    • Israeli Naval Medical Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 20 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: seasickness susceptibility and vestibular time constant; All study participants underwent rotatory chair testing in a velocity step protocol to determine the Vestibular time constant. testing were preformed at baseline, before commencing active duty on a ship, 3 month and 6 month follow up after the beginning of active sailing.

Diagnostic test: rotatory 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
6 month follow up vestibular time constant measurement.	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.	6 months

Collaborators and Investigators

• Sponsor: Medical Corps, Israel Defense Force

Study record dates

Study Major Dates

• Study Start (Actual): September 18, 2017
• Primary Completion (Actual): January 26, 2020
• Study Completion (Actual): July 26, 2020

Study Registration Dates

• First Submitted: November 28, 2022
• First Submitted That Met QC Criteria: November 28, 2022
• First Posted (Actual): December 7, 2022

Study Record Updates

• Last Update Posted (Actual): December 14, 2022
• Last Update Submitted That Met QC Criteria: December 12, 2022
• Last Verified: November 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Motion Sickness
• Other Study ID Numbers: IDF-1710-2016

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No
• IPD Plan Description: The data that supports the findings of this study are available upon request from the corresponding author, Tal D.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No