Concussion and vision testing in sports: Insights for legal review

Traumatic Brain InjuryVision Evaluations
Written By Steven H. Rauchman, MD

An athlete takes a blow to the head during a contact sport. There may be no immediate symptoms. Yet within minutes, a trainer pulls them from the game to complete a rapid visual test on a tablet. The goal of this test is to determine if brain function may be compromised. This approach often includes the King-Devick test, designed to assess how efficiently the eyes and brain work together following head trauma.

This pattern frequently appears in post-traumatic evaluations, where changes in visual tracking or speed may indicate deeper neurologic involvement.

Football player holds head in pain

How eye movements reveal brain function

The brain controls eye movements in two specific ways:

  • Smooth pursuit lets the eyes follow slow-moving objects, like tracking a plane across the sky.

  • Saccades are quick, jump-like movements used to shift focus, especially when something appears suddenly in the peripheral vision.

These two eye movement types work together during activities like reading, where smooth pursuit helps move across a line of text, and saccades jump the eyes to the next line. Both are essential for daily functioning. After a traumatic brain injury (TBI), even a mild one, these eye movements can be disrupted.

Common issues in post-traumatic evaluations include:

  • Slower reading

  • Trouble tracking motion

  • Visual fatigue

What the King-Devick test measures

The King-Devick test is a timed eye movement test often used on the sidelines after a potential head injury. The person is asked to quickly read a series of numbers displayed on a screen. The test checks how efficiently the eyes and brain can coordinate during rapid visual tasks. While not a diagnostic tool on its own, the test is a valuable part of a broader assessment protocol after a suspected concussion.

Key points about the King-Devick test:

  • It’s commonly used in sports settings to decide whether a player should return to play.

  • It gives a numeric score that can be compared to pre-injury baseline results.

  • A slower completion time or errors may suggest a possible brain injury.

Supporting tools: Vision symptom surveys

To supplement timed eye tests, clinicians may use symptom-based questionnaires. One commonly used tool is BIVSS (Brain Injury Vision Symptom Survey), a 28-question survey that helps identify people with mild to moderate TBI based on their visual symptoms.

The BIVSS can be used multiple times over the course of recovery to monitor changes or improvements in visual function. It helps capture patient-reported symptoms like blurred vision, trouble focusing, and difficulty reading. Other vision or TBI-related questionnaires may also be part of a patient’s evaluation and ongoing care.

Why this matters in legal injury cases

For legal professionals reviewing sports injuries, especially in cases involving concussion or return-to-play decisions, these tools can provide:

  • Objective data from eye movement testing

  • Corroboration of symptoms like reading difficulty or slowed reaction time

  • Support for timeline reconstruction, especially in cases with delayed symptom onset

Because eye movement impairments are often not visible during routine exams, the use of structured tests like King-Devick and BIVSS can help document subtle but functionally significant changes after head trauma.

Consult Dr. Rauchman for trusted medical-legal analysis

Submit Contact Form
Steven H. Rauchman, MD
Next

Clinical considerations in slip and fall TBIs among older adults