16 July 2026

Quantitative Pupillometry Research Supports Objective Concussion Assessment for Service Members

Mild traumatic brain injury (mTBI), commonly known as concussion, remains one of the most common injuries affecting Service members. Diagnosing and monitoring concussion can be challenging since symptoms can vary widely, and many evaluation methods rely on self-reported symptoms or clinical observation.  

Recent studies examining quantitative pupillometry, a technology that measures how the pupil responds to light, suggest that subtle changes in the eyes’ reflexes may provide measurable indicators of brain recovery following a concussion. 

Studying concussion recovery in military cadets 

Dr. Kenneth L. Cameron, co-principal investigator for the study and the Director of Orthopaedic and Sports Medicine Research at Keller Army Community Hospital at the U.S. Military Academy at West Point, led a team of investigators in collaboration with LTC Bradley Dengler, MD at the Uniformed Services University to study whether pupillary light reflex measurements can serve as a biomarker for concussion diagnosis and recovery, and whether pupillary measurements could predict recovery timelines. 

Objective measurements for concussion care 

Despite advances in concussion care, clinicians still face challenges when diagnosing and monitoring mTBI recovery. Standard evaluation tools, including symptom checklists, cognitive testing, and balance assessments, remain important components of care. Many of these approaches depend on patient-reported symptoms or examiner interpretation. 

Quantitative pupillometry offers a different type of assessment by measuring pupillary light reflexes, which reflect autonomic nervous system function. Using handheld devices, clinicians can capture pupil reflex data in seconds and generate objective measurements that can be tracked throughout recovery. 

For military populations, objective tools that support concussion evaluation are particularly important. The researchers noted that quantitative pupillometry, given its ease of use and rapid output, could be used in far-forward military operations to aid in diagnosis. Service members often train and operate in demanding environments where early identification of brain injury and careful monitoring of recovery can support both individual health and operational readiness. 

Studying recovery patterns following concussion 

The study involved collecting baseline clinical and pupillary measurements from cadets and repeating those assessments when a concussion occurred during training or other military activities. By comparing post-injury measurements with baseline data, researchers observed how pupillary responses changed after concussion and how those responses evolved during recovery. 

Cadets who sustained mTBI showed measurable differences in several pupillary metrics following concussion, including changes in pupil diameter and constriction velocity. Researchers observed two distinct recovery patterns in pupillary responses. Some measures, such as changes in pupil diameter difference and dilation velocity, gradually returned toward baseline levels as cadets progressed through recovery. In contrast, other measures, such as initial and ending pupil diameter, remained significantly different from baseline even when cadets were medically cleared to return to full duty. 

Researchers also examined whether quantitative pupillometry could help estimate recovery timelines following concussion. They identified relationships between certain pupillary measurements and the amount of time required before cadets returned to unrestricted activity. These findings suggest that pupillometry measurements may provide clinicians with additional information to evaluate concussion recovery and readiness to resume full activity. 

The research also demonstrated that quantitative pupillometry measurements may be useful in tracking the clinical progression of concussion over time, providing another potential tool to help monitor recovery following mTBI. 

Advancing research that supports readiness 

The Geneva Foundation advances military medical research programs that aim to improve care for service members and strengthen operational readiness. Through research administration and operational expertise, Geneva enables investigators to conduct studies that expand understanding of traumatic brain injury and evaluate emerging diagnostic tools. 

Research exploring quantitative pupillometry reflects ongoing collaboration among military research institutions and clinical experts working to improve concussion care for service members. As additional data are collected and analyzed, these objective measurements may help clinicians better monitor recovery and support informed return to duty decisions. 

Continued research in this area contributes to broader efforts to improve the diagnosis, monitoring, and management of traumatic brain injury across military populations. By advancing studies like these, Geneva helps translate scientific knowledge into practical tools for clinicians caring for those who serve. 

Explore more about this research 

Quantitative pupillometry as a biomarker for prediction of return to play in mild traumatic brain injury: a Military Traumatic Brain Injury Initiative study – https://pubmed.ncbi.nlm.nih.gov/38950435/

Quantitative Pupillometry Predicts Return to Play and Tracks the Clinical Evolution of Mild Traumatic Brain Injury in US Military Academy Cadets: A Military Traumatic Brain Injury Initiative Study – https://scholar.usuhs.edu/en/publications/quantitative-pupillometry-predicts-return-to-play-and-trac… 

Aderman MJ, Meister MR, Houston MN, Dengler BA, Ross JR, Malvasi SM, Cameron KL. Normative Values for Pupillary Light Reflex Metrics Among Healthy Service Academy Cadets. Mil Med. 2023. Accepted for publication 16 May 2023. PMID: 37522744 

Disclaimer: The views expressed do not reflect the official policy of the Army, the Department of War, or the U.S. Government.