Novel Kinematic Methods for Detecting Vestibular Loss in Veterans

Project Background/Rationale: The purpose of this proposal is to improve our techniques for testing peripheral vestibular (inner-ear balance) function in Veterans. Vestibular loss is a leading culprit for imbalance and falls, which are among the top reasons for health care visits and a leading cause of mortality particularly in older people. Vestibular loss can be due to exposure to ototoxic antibiotics or chemotherapeutic agents, trauma during otologic surgery including cochlear implantation, aging, inflammatory or infectious processes, or other causes. In many clinical situations, the detection of small losses in vestibular function could motivate alternative therapeutic approaches or a change in surgical planning, thereby preventing the development of further losses leading to potentially disabling symptoms. While current vestibular tests are good at detecting large losses, they are not adequate for identifying more subtle lesions. Project Aims: There is a need to develop new vestibular tests better able to identify small losses in vestibular function. Here, we will investigate the ability of kinematic testing using inertial sensors to meet that need. This technique analyzes the outputs of multiple body-worn sensors recording movement and orientation of parts of the body while performing various activities. The specific aims of this research proposal are to (1) develop improved test paradigms for collecting kinematic data; (2) evaluate alternative kinematic sensor technologies; and 3) collect pilot data for future large-scale comparisons of kinematic and conventional tests of vestibular function. Project Methods: The first two aims of this 2-year pilot project will be accomplished by comparing kinematic performance between normal controls (n=10) and patients with complete unilateral vestibular loss (n=10). The third aim will involve patients at risk for minor vestibular loss due to cochlear implant surgery (n=15). We will compare changes in their kinematic performance during surgery to analogous changes in their conventional vestibular tests. Kinematic testing methods will include measures of stance (movement of head and body while standing on foam in the dark) and gait (head angular distance, velocity, and acceleration while rotating the head about the yaw axis) while conventional tests will include video head impulse testing and cervical vestibular-evoked myogenic potential. Subjective imbalance will be quantified using subjective questionnaires. This will allow us to evaluate the relative ability of each testing modality to identify minor vestibular losses. Anticipated Impact: Completion of the proposed study will demonstrate that kinematic testing can measure small changes in vestibular function inexpensively, simply, reliably, and accurately. This will provide solid scientific footing for incorporation of kinematic testing into standard vestibular testing paradigms. Results of this study will lead to a VA Rehabilitation Research & Development Merit Award application exploring the applicability of kinematic tests to evaluating vestibular function among patients with diverse causes for potential vestibular loss and establishing best practices for monitoring vestibular function in sets of patients at risk. This research is highly significant because successful completion of these studies will reduce the incidence of severe vestibular loss and the impact of vestibular loss among Veterans. Project Number: 1I21RX005452-01 | Fiscal Year: 2025 | NIH Institute/Center: Veterans Affairs (VA) | Principal Investigator: TIMOTHY HULLAR | Institution: PORTLAND VA MEDICAL CENTER, PORTLAND, OR | Activity Code: I21 | Study Section: Rehabilitation Research and Development SPiRE Program[RRDS] View on NIH RePORTER: https://reporter.nih.gov/project-details/11053398