Concussion Diagnostics: How We Evaluate Concussion in Children and Teens
Concussions can happen anywhere and everywhere – from the school yard to the playing field, from the playground to the home. Historically, clinicians have had to rely on symptom self-reporting from patients and observational reporting from parents and family members.
A team of clinicians and researchers from CHOP’s Minds Matter Concussion Program have developed and are evaluating several cutting-edge tools to better diagnose concussion in youth, provide information regarding prognosis, and assess treatment outcomes. These concussion diagnostic tools include:
- Visio-vestibular exam (VVE), which assesses eye movements and balance
- Measuring gait and balance
- Pupillary light reflex (Pupillometer)
- Exercise testing
The visio-vestibular examination (VVE) is a series of physical exam maneuvers that tests the concussed youth’s vision and the function of their vestibular system, which controls elements such as balance and eye movements. The exam evaluates both abnormal signs (such as abnormal movement of the eyes during testing) as well as the provocation of symptoms.
VVE includes testing of:
- Smooth pursuits — how well an affected youth can track a moving object on a single plane
- Horizontal and vertical saccadic eye movements — evaluating for abnormal eye movements or symptom provocation as the eyes move between two fixed objects
- Horizontal and vertical gaze stability (the vestibulo-ocular reflex) — evaluating for abnormal signs or symptom provocation as a youth’s eyes remain fixed on an object when they move their head up and down, or side to side
- Near point-of-convergence and monocular accommodation — how close an object can get the youth’s face before it appears to double or becomes blurry
- Tandem gait and balance, while walking toe-to-heel, forward and backwards, with their eyes open and closed, looking for sway and steps off a straight line
Learn more about our team’s ongoing research into visio-vestibular markers for concussion and how this line of research has the potential to improve concussion diagnosis and recovery.
Automated eye-tracking assessment
The automated eye tracking assessment is a rapid, objective and non-invasive aid in the diagnosis of concussion and does not require a patient’s pre-injury baseline as a comparison to identify concussion. This eye-tracking methodology reflects the brain’s natural and automatic activity and can be an alternative to traditional subjective, symptom-based assessments.
During the assessment, a clinician records a patient’s eye movements with an eye tracking device while they watch a nearly 4-minute video. The patient’s head is stabilized on a chin rest to minimize head movements and data is automatically collected and processed to assess how well the eyes move together.
CHOP researchers were among the first to evaluate this technology as an objective method for identifying concussions in young patients. In 2019, the Oculogica EyeBOX® received FDA approval as one of the few devices cleared for commercial use in the diagnosis of concussion.
Measuring gait and balance
CHOP researchers have studied three tools to evaluate whether gait and balance measurements could be helpful in diagnosing concussion in youth, including:
- A biomedical force plate device, a device-based measure
- The Modified Balance Error Scoring System (mBESS), a standardized exam that’s part of the Sport Concussion Assessment Tool
- Complex tandem gait, an evaluation used in the visio-vestibular exam developed at CHOP
Our research showed the complex tandem gait evaluation possessed the greatest sensitivity in diagnosing – and ruling out – concussion.
In this video, Dan Corwin, MD, MSCE, discusses how complex tandem gait can be used in diagnosing concussion.
Saccades and gaze stability assessments
Our clinical researchers also completed a study of concussed and healthy athletes to evaluate the optimal number of repetitions of saccades (side-to-side eye movements) and gaze stability (up-and-down eye movements) assessments at different repetition increments to differentiate youth with concussion and those without.
Increasing the repetitions improved the sensitivity of each assessment, but when we combined results of eye movement in both the horizontal and vertical plane, our team determined 20 repetitions allowed clinicians to diagnose youth concussion more accurately.
Pupillary light reflex
One of the most promising new concussion diagnostic tools is the automated dynamic infrared pupillometry hand-held device – commonly called the pupillometer – which measures the pupil’s automated response to light. This is an exciting correlate to assess autonomic dysfunction – abnormalities in the part of the nervous system that is controlled automatically by the brain – that CHOP researchers have found to be a key component driving a child’s symptoms after an injury.
In a recent study, CHOP researchers explored whether pupillary light reflex (PLR) measured by the pupillometer could distinguish between youth with concussion and those without. Researchers assessed nine specific PLR metrics and found significant differences between the concussed and non-concussed adolescents for eight of those studied.
Watch a video where Christina Master, MD, discusses the pupillometer and its impact on concussion knowledge.