Authors' recommendations: Mild TBIOverall, the findings from this qualitative systematic review provide moderately suggestive evidence for a range of vision sequelae primarily in the acute stages of mild TBI in younger clinically-based adult populations. The evidence is limited by small sample size and heterogeneity in the selection of cases and controls, injury severity criteria and outcome measures.In the acute stages following mild TBI, photosensitivity is a common complaint particularly in the Veteran population. The evidence suggests that while nearly half of the cases tend to experience photosensitivity in the acute phase following injury; this problem can persist for several weeks especially in the presence of post-concussive cognitive complaints. Moderately firm evidence exists for the presence of self-reported vision disorders (blurred vision and double vision) and saccadic deficits in the acute and chronic stages post injury. These common symptoms are not representative of the range of possible symptoms and impairments found in individuals with mild TBI, nor are they necessarily specific to an underlying mechanism of TBI.Findings from both meta-analyses and primary studies of neurocognitive dysfunction following mild TBI suggest resolution of these effects generally within 3 months, but data from longer time since injury are lacking. Preliminary evidence suggests that some domains of neurocognitive testing with respect to visual processing speed, visuospatial attention, and spatial memory may be sensitive to detecting persistent mild TBI.Moderate-severe TBIThese findings provide preliminary speculative evidence from one case series of Veteran patients and moderately-suggestive evidence from case-control studies of diffuse deficits to oculo-motor function and visual perception in clinically-and community-based populations with chronic moderate-severe TBI. Results suggest deficits often persist many years after injury. As with studies of mild TBI, the evidence base is limited by conduct and reporting of key study elements, specifically, small sample sizes, selection process of cases and controls, injury severity criteria and testing measures.Among Veterans with moderate-severe TBI, binocular dysfunction, pursuit and/or saccade deficits and visual spatial deficits were common. The rate of visual impairment with either overt blast injury or blast exposure was more than twice that of other mechanisms of injury, suggesting a need to conduct more comprehensive eye examination beyond refractive correction to uncover more pervasive visual deficits in this population, particularly those who complain of reading difficulty or photosensitivity.The preponderance of evidence from multiple studies suggests that moderate-severe TBI is associated with widespread deficits in attention, in particular in information processing speed and executive control of task switching in focused/selective and divided attention. Possible reasons underlying these impairments are a reduced resource capacity and impairment in self-regulation (Battistone 2008). Mathias (2007) stressed the need to account for the effect of the impairment in information processing speed when measuring other aspects of attention. Summers (2006) highlighted the role of inattentional blindness, i.e. the failure to identify significant but unexpected events that occur within a person’s visual field, and its implications on function and in design of rehabilitative models of care.Results from single case-control studies found higher frequencies of agnosia, apraxia and unilateral neglect, dark adaptation dysfunction and visual memory as well as impairment in body scheme and constructional skills in moderate-severe TBI subjects than in noninjured subjects.

Project Status: Completed

URL for project: http://www4.va.gov/VATAP/docs/VisualProblemsTBI2009tagm.pdf

Year Published: 2009

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: VA Technology Assessment Program

Contact Address: Liz Adams, VA Technology Assessment Program, Office of Patient Care Services (11T), VA Boston Healthcare System Room 4D-142, 150 South Huntington Avenue, Boston, MA 02130 USA Tel: +1 617 278 4469; Fax: +1 617 264 6587;

Contact Name: elizabeth.adams@med.va.gov

Contact Email: elizabeth.adams@med.va.gov

Copyright: VA Technology Assessment Program (VATAP)