PP1002 - Evaluation of Saccadometry in Concussion Patients vs. Individuals with Normal Vestibular Function

The proposed research is being conducted to evaluate how antisaccades are affected when a patient has a concussion compared to healthy individuals with normal vestibular function. This study aims to answer if there is a statistical difference in directional error rate, overall error rate, latency, and velocity during antisaccadic eye movements between these two groups. Results of this study will help inform clinical decisions related to vestibular assessment, treatment, and counseling for patients experiencing vestibular deficits of concussion.

Summary:

Rationale/Purpose

An ongoing need in the diagnosis and management of concussion is objective tests of function. The proposed research will evaluate how saccadic eye movements are affected when a patient has a concussion compared to a healthy individual with normal vestibular function. The research will also establish foundational clinical norms for the antisaccade subtest of saccadometry for clinical use in the Neuroaudiology Clinic at the University of Kansas Medical Center. This research is designed to further contribute to the emerging research on this topic. 

Data from the literature review not only supports saccadometry testing as a reliable test of central function in concussion patients but also supports the need for further research to characterize exact eye abnormalities, which will support the diagnoses and management of these patients (Ventura et al., 2016). Comparing eye movement abnormalities between concussion patients versus individuals with normal vestibular function will help members of the care team to further understand how central function is affected by concussion. If the comparisons between concussion individuals and individuals with normal vestibular function result in statistical significance, the clinical norms generated will assist in the monitoring of concussion patients and aid in the counseling of evidence-based practice. 

Based on previous research, we hypothesize that directional and overall error rates, as well as latencies, will be significantly greater during antisacadic eye movements in patients with concussions compared to healthy individuals. In addition, we hypothesize velocities during antisaccadic eye movements will be significantly reduced in patients with concussions compared to healthy individuals.

Methods

This study is designed as a combined retrospective chart review and prospective study. Previous saccadometry data from adult ( > 18) patients with concussion seen in the Neuroaudiology Department of The University of Kansas Health System will be reviewed and compared to a control-matched group of subjects who have normal vestibular function. We will evaluate the data using a multiple regression model for each independent variable. 

A priori power calculations estimated 88 participants to detect a small effect with the current research design and hypotheses (G*Power 3.1.9.7). No randomization is used for this study design as subjects will either be recruited for normal vestibular function in the prospective arm of the study, or identified as having a concussion through retrospective chart review. Descriptive statistics of the chart-reviewed population will inform prospective recruitment so the team can attempt to match the age, gender, and ethnic origin of the concussion population. Linear mixed effect and regression models will be evaluated to compare data within groups (concussion/normal) and between groups. The target enrollment for this study is 44 prospective adult participants over 18. This allows the detection of a small effect for the main study question related to saccadometry results for normal and concussion groups. 

Results & Conclusions

Research is currently being conducted with a target completion of data collection in February 2024.