There is a growing body of evidence that concussion can impair eye movement. Over a series of research publications, CIRP’s Minds Matter researchers describe these deficits in eyes after concussion as seen in clinical settings and their association with prolonged recovery after concussion.
Researchers have also been testing the utility of a visio-vestibular exam to detect deficits in eyes after concussion in pediatric and adolescent patients and the use of eye tracking technology to objectively measure these deficits. They have learned that such clinical tools are both effective and feasible and important for diagnosis and recovery.
This has important implications for the management of eyes after concussion. Active rehabilitation therapy can be used to treat those with prolonged persisting symptoms, and specific academic accommodations targeting these visio-vestibular deficits can be made for these children when returning to the learning setting.
- Learn more about the vestibular system in this blog
- Learn more about the vision disorders after concussion in this blog
- Read a press release about this line of research
Areas of Research on Eyes After Concussion:
- Vision and Vestibular System Dysfunction Predicts Prolonged Concussion Recovery in Children – This study looked retrospectively at 432 randomly selected children ages 5-18 years who were seen in a specialty concussion program, of which 88 percent presented with a visio-vestibular deficit on initial clinical examination. Deficits in smooth pursuit and vestibular-ocular reflex function, accommodative amplitude and balance predicted prolonged concussion recovery. Clinical Journal of Sports Medicine. March 2018.
- Vision Diagnoses Are Common After Concussion in Adolescents -- In a single-center cross-sectional study of 100 patients with concussion enrolled at the Minds Matter concussion program at CHOP, 69 percent had at least one vision diagnosis after concussion. Clinician researchers found the Convergence Insuffiency Symptom Survey (CISS) to be a highly cost-effective means for general practitioners to identify patients with concussion-related vision deficits that could require referral to concussion specialist or eye care professional. Clinical Pediatrics. July 2015. Read this blog article for more details.
- Vestibular Deficits Following Youth Concussion -- In a retrospective cohort study of patients ages 5 to 18 referred to a sports medicine clinic, researchers sought to characterize the prevalence and recovery of pediatric patients with concussion who manifest clinical vestibular deficits, as well as describe the correlation of vestibular deficits with neurocognitive function based on computerized neurocognitive testing. Vestibular deficits were highly prevalent, associated with longer recovery and poorer outcomes in neurocognitive testing. The Journal of Pediatrics. March 2015. Read this blog article for more details.
- Occulomotor and Cognitive Test in Youth with Concussion --This study looked for correlations between different baseline assessments for concussion used for child and adolescent athletes: King-Devick (K-D) is a number-naming test assessing saccadic eye movement, ImPACT assesses working memory, visual motor speed and reaction time, while SCAT3 assesses working memory, concentration, and balance. In addition to these assessment tools, researchers wanted to see if useful information could be also obtained by measuring near point of convergence (NPC), the point at which a single visual object becomes double in near vision. In this study of youth hockey players ages 6-18 years, researchers ultimately determined that use of multiple assessment tools in a clinical evaluation of pediatric concussion is warranted rather than relying on any single tool. Also, the results suggest that the pediatric population may require more frequent than annual baseline testing. Additional research is needed to determine which combination of assessments will be most useful and non-overlapping. Developmental Neuropsychology. February 2015.
- Characteristics of Prolonged Recovery – This study identified pre-existing characteristics (depression, anxiety) and presenting symptoms (abnormal oculomotor, dizziness) associated with prolonged recovery from concussion in a sample of patients referred to a pediatric sports medicine clinic. Journal Pediatrics. December 2014. Read this blog article for more details.
Principal Investigators: Christina L. Master MD, CAQSM; Daniel J. Corwin, MD, MSCE; Funding: multiple
The visio-vestibular exam (VVE) identifies visual and vestibular system deficits which aid in the diagnosis of concussion and can predict prolonged recovery in those who are identified as having such deficits. These systems are responsible for integrating balance, vision and movement. Understanding these deficits early can have a substantial impact on a child’s visual function ability to return to learn and sports after a concussion.
The VVE screening assesses how eyes track a moving object, jump quickly between visual targets and their ability to view an object at near distance without double vision. Taken in the context of a preceding injury, abnormalities on this testing can assist in the diagnosis of concussion, as well as potentially aid in predicting children who will suffer from prolonged symptoms.
- Use of the Vestibular and Oculomotor Examination For Concussion In a Pediatric Emergency Department – This study analyzed patient charts of 400 children ages 6-18 who presented to the emergency department (ED) over a 12-month period in 2016-2107 with head injury and were considered to potentially have a concussion by the provider caring for them. Researchers found that 64 percent of the patients were assessed using the VVE. Of those ultimately diagnosed with concussion, 73 percent were assessed using the VVE, 9 percent of patients diagnosed with a concussion had one or fewer symptoms but abnormal exam findings, highlighting that the VVE can assist in more accurately identifying concussed patients. Patterns of use of the VVE differed among the types of authorizing providers in the ED: In patients diagnosed with a concussion, 92 percent of those were seen by an advanced practice provider, 88 percent were seen by a pediatrician, and 69 percent were seen by a pediatric emergency medicine physician received VVE testing. The VVE exam was more likely to be performed on those children with some common features of concussion. In those children with non-sports related injuries, minimal concussion symptoms, and no prior history of concussion, the VVE exam was less likely to be administered. With training and clinical support tools, pediatricians, emergency medicine clinicians, and advanced practice practitioners are able to conduct the VVE in a high volume acute care setting. American Journal of Emergency Medicine. September 2018. Principal Investigator: Daniel J. Corwin, MD, MSCE; Funding: National Institutes of Health
Automated eye tracking assessment
The automated eye tracking assessment is a rapid, objective, non-invasive aid in the diagnosis of concussion and it does not require an individual patient’s pre-injury baseline as a comparison to identify a concussion. This eye-tracking methodology reflects natural automatic physiologic brain activity and, thus, can be an objective alternative to traditional subjective, symptom-based assessments.
During the assessment, a clinician records a patient’s binocular eye movements with an SR Research Eyelink 1000 eye tracker while they are watching a 220-second video move continuously within a square aperture on the monitor as the patients head is stabilized on a chin rest to minimize head movement. Data collected are automatically processed using Oculogica software to yield metrics relevant to conjugacy, or the ability of the eyes to move well together. In collaboration with other institutions, CIRP researchers evaluated this technology as an objective method for identifying concussions in young patients.
- Objective Eye Tracking Deficits Following Concussion for Youth Seen in a Sports Medicine Setting – This study evaluated eye tracking measurements among adolescents within 10 days of the injury and healthy controls (n = 79). From among 17 metrics analyzed in this study, one metric measured by the automated eye tracking assessment stood out: The right eye’s ability to track an object predicted overall symptom severity among patients with concussion as compared to healthy controls. Child Neurology. Aug 2018.
- Eye Tracking as a Biomarker for Concussion in Children – This study evaluated eye tracking measurements among children with concussion seen in a concussion referral setting with a mean of 22 days out from injury and healthy controls (n = 139). For these patients there were 12 metrics from 89 evaluated that were significantly different between concussed and non-concussed children. The assessment’s detection of concussion was independent from the number of symptoms reported by the patient. Clinical Journal of Sports Medicine. Aug 2018.
Lead CIRP Investigator: Christina L Master, MD, CAQSM; Funding: National Institutes of Health, Centers for Disease Control and Prevention, NCAA, Department of Defense