Pritam Dutta, M.Optom
Lecturer, Ridley College of Optometry, Optometrist, Chandraprabha Eye Hospital Jorhat, Assam
Traumatic Brain Injury (TBI) is defined, “as an alteration in brain function, or other evidence of brain pathology, caused by an external force”1. The mode of TBI can be either due to falls, assaults, road traffic accidents, pedestrian accidents, sports-related, industrial and workplace-related accidents2. Among all, mild TBI accounts for 75% alone3. The American Congress of Rehabilitation Medicine (ACRM) defined mild TBI as “traumatically induced physiological disruption of brain function, as manifested by at least one of the following: any period of loss of consciousness, any loss of memory for events immediately before or after the accident, an alteration in the mental state at the time of the accident (disoriented or confused), focal neurological deficit that may or may not be transient”.
There occurs a cellular and sub cellular level damage in mild TBI without the involvement of any haemorrhage or any changes detectable in imaging techniques4. Visual symptoms following TBI include near vision problems with prolonged reading, glare, photosensitivity, and difficulty maintaining fusion5. The most common symptoms an individual develops following mild TBI are headache, dizziness, fatigue, irritability, insomnia, difficulty concentrating, memory problems, and/or intolerance of stress6. Several studies have found convergence insufficiency, accommodative dysfunction, and oculomotor problems to be the commonest among patients following mild TBI7 (see Table 1). It is reported that there occurs a diffuse and multiple axonal damages which in turn causes disruption of accommodation and vergence neural nerve fibers leading to certain dysfunctions8. The saccade and pursuit share a common premotor neural pathway which contains neurons of inhibitory omnipause and neurons of pursuits and saccades in the paramedian pontine reticular formation (PPRF) and any lesions following TBI to this area leads to oculomotor dysfunction9. These alterations in the accommodation, vergence and versions also have an impact on the academic performances of adult/children, leading to lack of concentration, difficulty performing near tasks, and asthenopia which results in achieving lower grade points when compared to a non-TBI child10,11.
Common ocular conditions | Findings in mild TBI |
Accommodation | Reduced amplitude, time constant, peak accommodative velocity12 |
Vergence | Reduced convergence amplitude and poor fusional vergence13 |
Oculomotor based reading dysfunction | Reduced reading speed, poor comprehension, deficit in saccades and pursuits14,15 |
Photosensitivity | Found in a larger prevalence of mild TBI individuals due to poor pupillary dynamics16 |
Pupillary response | Delayed pupillary latencies and velocities17 |
Visual memory | Impaired18 |
Vestibular dysfunction | Associated with symptoms such as blurred vision, dizziness, nausea etc. due to various neurometabolic changes occurring following a mild TBI19 |
Visual field |
Scattered, restricted; might be homonymous 22 |
Table 1: Common ocular findings in mild TBI.
A thorough ocular examination including the tests for binocular vision, eye movements, visual processing and visual efficiency would provide an estimation of the underlying abnormalities in mild TBI individuals. Therefore, eye care professionals play a crucial role in diagnosing and treating these visual consequences, working as an integrated team in a hospital or an individual set up. The Neuro-optometric based vision therapy and other treatment modalities (see Table 2) along with a proper referral for managing the associated non-ocular based problem would significantly make a difference in improving the quality of life in those patients.
Conditions | Management options |
Accommodation | Accommodative training (vision therapy)15 |
Vergence | Vergence training (vision therapy)15 |
Reading deficits | Oculomotor rehabilitation15 |
Photosensitivity | Tinted glass20 |
Vestibular dysfunction | Vestibular therapy20,21 |
Visual field | Prisms and visual scanning20,21 |
Table 2: Management options for associated conditions following mild TBI.
References:
- Thomas R.Frieden FSC. Report to Congress on Traumatic Brain Injury in the United States : Understanding the Public Health Problem among Current and Former Military Personnel.; 2013.
- Reznik, J. E., Biros, E., Marshall, R., et.al. (2014). Prevalence and risk-factors of neurogenic heterotopic ossification in traumatic spinal cord and traumatic brain injured patients admitted to specialised units in Australia. Journal of musculoskeletal & neuronal interactions, 14(1), 19–28.
- Dewan, M. C., Rattani, A., Gupta, S.et. al. (2018). Estimating the global incidence of traumatic brain injury, Journal of Neurosurgery JNS, 130(4), 1080-1097.
- Barnett, B. P., & Singman, E. L. (2015). Vision concerns after mild traumatic brain injury. Current treatment options in neurology, 17(2), 329. https://doi.org/10.1007/s11940-014-0329-y
- Padula W V, Simmons-grab D, Cannelongo J, et al. Visual Dysfunction Following a Neurological Event. NORA. 1995
- Barlow, K. M. (2016). Postconcussion Syndrome: A Review. Journal of Child Neurology, 31(1), 57–67. https://doi.org/10.1177/0883073814543305
- Matuseviciene, G., Johansson, J., Möller, M., et al. (2018).Longitudinal changes in oculomotor function in young adults with mild traumatic brain injury in Sweden: an exploratory prospective observational study. BMJ open, 8(2), e018734. https://doi.org/10.1136/bmjopen-2017-018734
- Searle, A., & Rowe, F. J. (2016). Vergence Neural Pathways: A Systematic Narrative Literature Review. Neuro-ophthalmology (Aeolus Press), 40(5), 209–218. https://doi.org/10.1080/01658107.2016.1217028
- Ciuffreda, K. J., Kapoor, N., Rutner, D., et.al. (2007). Occurrence of oculomotor dysfunctions in acquired brain injury: a retrospective analysis. Optometry (St. Louis, Mo.), 78(4), 155–161. https://doi.org/10.1016/j.optm.2006.11.011
- Russell, K., Hutchison, M. G., Selci, E., et.al. (2016). Academic Outcomes in High-School Students after a Concussion: A Retrospective Population-Based Analysis. PloS one, 11(10), e0165116. https://doi.org/10.1371/journal.pone.0165116
- Swanson, M. W., Weise, K. K., Dreer, L. E., et.al. (2017). Academic Difficulty and Vision Symptoms in Children with Concussion. Optometry and vision science : official publication of the American Academy of Optometry, 94(1), 60–67. https://doi.org/10.1097/OPX.0000000000000977
- Green, W., Ciuffreda, K. J., Thiagarajan, P., et.al. (2010). Accommodation in mild traumatic brain injury. Journal of rehabilitation research and development, 47(3), 183–199. https://doi.org/10.1682/jrrd.2009.04.0041
- Szymanowicz, D., Ciuffreda, K. J., Thiagarajan, P., et.al. (2012). Vergence in mild traumatic brain injury: a pilot study. Journal of rehabilitation research and development, 49(7), 1083–1100. https://doi.org/10.1682/jrrd.2010.07.0129
- Capó-Aponte, J. E., Urosevich, T. G., Temme, L. A., et. al. (2012). Visual dysfunctions and symptoms during the subacute stage of blast-induced mild traumatic brain injury. Military medicine, 177(7), 804–813. https://doi.org/10.7205/milmed-d-12-00061
- Thiagarajan, P., Ciuffreda, K. J., Capo-Aponte, J. E., et.al. (2014). Oculomotor neurorehabilitation for reading in mild traumatic brain injury (mTBI): an integrative approach. NeuroRehabilitation, 34(1), 129–146. https://doi.org/10.3233/NRE-131025
- Truong, J. Q., & Ciuffreda, K. J. (2016). Objective Pupillary Correlates of Photosensitivity in the Normal and Mild Traumatic Brain Injury Populations. Military medicine, 181(10), 1382–1390. https://doi.org/10.7205/MILMED-D-15-00587
- Ciuffreda, K. J., Joshi, N. R., & Truong, J. Q. (2017). Understanding the effects of mild traumatic brain injury on the pupillary light reflex. Concussion (London, England), 2(3), CNC36. https://doi.org/10.2217/cnc-2016-0029
- Arciniega, H., Kilgore-Gomez, A., Harris, A., et.al. (2019). Visual working memory deficits in undergraduates with a history of mild traumatic brain injury. Attention, perception & psychophysics, 81(8), 2597–2603. https://doi.org/10.3758/s13414-019-01774-9
- Gurley, J. M., Hujsak, B. D., & Kelly, J. L. (2013). Vestibular rehabilitation following mild traumatic brain injury. NeuroRehabilitation, 32(3), 519–528. https://doi.org/10.3233/NRE-130874
- Ciuffreda, Kenneth & Diana, O & Ludlam, Diana. (2011). Conceptual Model of Optometric Vision Care in Mild Traumatic Brain Injury. The Journal of Behavioral Optometry. 22.
- Ciuffreda, K.J., Ludlam, D.P., & Kapoor, N. (2009). Clinical Oculomotor Training in Traumatic Brain Injury.
- Suchoff, I. B., Kapoor, N., Ciuffreda, K. J., et.al. (2008). The frequency of occurrence, types, and characteristics of visual field defects in acquired brain injury: a retrospective analysis. Optometry (St. Louis, Mo.), 79(5), 259–265. https://doi.org/10.1016/j.optm.2007.10.012
Thank you to the author for providing indepth details of such an unaddressed field
Quite informative with adequate content and thank you to the author for providing the details in a tabular format for better understanding. Appreciable
Very informative. What does the neuro imaging reflects in mild TBI cases ?
Thank you. The CT/MRI often shows no abnormalities in mild cases because it is thought to be a kind of diffuse axonal injury as a resultant of mild TBI
Quite interesting. Never knew that traumatic brain injury is also an area where optometrist could work in diagnosing and managing the sequelae
Very interesting to know some unknown facts
Is it important to measure the static and dynamic response of accommodation in order to make a conclusion in TBI ?
Interesting article and few unknown facts
The dynamic measures would basically include the peak velocities , latencies…..to make a conclusion of accommodation anomalies ( if present) a thorough binocular vision assessment would also work but for precise measurements the dynamic responsivity would actually work well
Kudos to the author for taking up such an unexplored area in Optometry
Appreciate the author for the content. Quite informative.
Never thought TBI would also affect the visual system in a gross manner. Appreciating the author for providing the basic concept of approaching such cases
Very interesting !! Looks like the author has put up adequate info for the beginners to actually understand the problem