Photophobia Associated with Traumatic Brain Injury: A Systematic Review and Meta-analysis.

SIGNIFICANCE: This study reports the prevalence and relative risk of photophobia in patients with traumatic brain injury (TBI). OBJECTIVES: This study aimed to conduct a systematic review and meta-analysis to determine the prevalence and relative risk of photophobia in patients with TBI. DATA SOURCES: Three databases were used for literature search: PubMed, EMBASE, and Cochrane Library. STUDY APPRAISAL AND SYNTHESIS METHODS: Publications reporting the prevalence of photophobia after TBI in patients of any age were included. A series of meta-regression analyses based on a generalized linear mixed model was performed to identify potential sources of heterogeneity in the prevalence estimates. RESULTS: Seventy-five eligible publications were identified. The prevalence of photophobia was 30.46% (95% confidence interval [CI], 20.05 to 40.88%) at 1 week after the injury. Prevalence decreased to 19.34% (95% CI, 10.40 to 28.27%) between 1 week and 1 month after TBI and to 13.51% (95% CI, 5.77 to 21.24%) between 1 and 3 months after the injury. The rapid decrease in the prevalence of photophobia in the first 3 months after a TBI injury was significant (P < .001). Three months post-TBI, the prevalence of photophobia leveled off to a near plateau with nonsignificant variability, increasing between 3 and 6 months (17.68%; 95% CI, 9.05 to 26.32%) and decreasing between 6 and 12 months since TBI (14.85%; 95% CI, 6.80 to 22.90%). Subgroup analysis of 14 publications that contained control data showed that the estimated risk ratio for photophobia was significantly higher in the TBI than in the control group during the entire 12 months after TBI. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: This study demonstrates that photophobia is a frequent complaint after TBI, which largely resolves for many individuals within 3 months after the injury. For some patients, however, photophobia can last up to 12 months and possibly longer. Developing an objective quantitative methodology for measuring photophobia, validating a dedicated photophobia questionnaire, and having a specific photophobia International Classification of Diseases, Tenth Revision code would greatly improve data gathering and analysis.

Incidence and temporal presentation of visual dysfunction following diagnosis of traumatic brain injury, active component, U.S. Armed Forces, 2006-2017.

This analysis describes the incidence of visual dysfunctions following a diagnosis of traumatic brain injury (TBI) among active component service members. The visual dysfunctions were divided into 9 major categories. A comparison group of service members with no history of TBI was used to determine relative incidence rates. The most commonly diagnosed visual dysfunctions were subjective visual disturbances, convergence insufficiency (CI), visual field loss, and accommodative dysfunction (AD). Service members with mild or moderate/severe TBI had significantly higher incidences of AD and CI compared to service members with no TBI. Results of survival analysis showed that service members with mild or moderate/severe TBI had lower probabilities of remaining without the visual dysfunction outcome at almost every week of follow-up in the first year after TBI diagnosis compared to those with no TBI. The findings of this report suggest opportunities to improve both documentation and access to care for service members with these conditions.

Visual Deficits and Dysfunctions Associated with Traumatic Brain Injury: A Systematic Review and Meta-analysis.

SIGNIFICANCE: This study reports prevalence data combined independently for accommodative dysfunction, convergence insufficiency, visual field loss, and visual acuity loss in patients with traumatic brain injury in the absence of eye injury. OBJECTIVE: The objective of this study was to conduct a systematic review and meta-analysis to determine the prevalence rates of accommodative dysfunction, convergence insufficiency, visual field loss, and visual acuity loss in TBI patients without concomitant eye injury. DATA SOURCES: The data sources used in this study were PubMed, EMBASE, EBSCO, and Cochrane Library. STUDY APPRAISAL AND SYNTHESIS METHODS: Publications reporting the prevalence of diagnosed accommodative dysfunction, convergence insufficiency, visual field loss, or visual acuity loss to the level of legal blindness in TBI patients of any age were included. Univariate metaregression analyses and subgroup analyses were performed to account for statistical heterogeneity. RESULTS: Twenty-two eligible publications were identified across the four visual conditions. Random-effects models yielded combined prevalence estimates: accommodative dysfunction (42.8; 95% confidence interval [CI], 31.3 to 54.7), convergence insufficiency (36.3%; 95% CI, 28.2 to 44.9%), visual field loss (18.2%; 95% CI, 10.6 to 27.1%), and visual acuity loss (0.0%; 95% CI, 0.0 to 1.1%). Metaregression and subgroup analyses revealed that visual field loss was significantly more prevalent in moderate to severe (39.8%; 95% CI, 29.8 to 50.3%) compared with mild TBI (6.6%; 95% CI, 0 to 19.5%). CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: This study demonstrates that accommodative dysfunction, convergence insufficiency, and visual field loss are common sequelae of TBI. Prospective longitudinal research with rigorous and uniform methodology is needed to better understand short- and long-term effects of TBI on the vision system.

Nutritional manipulation of primate retinas, V: effects of lutein, zeaxanthin, and n-3 fatty acids on retinal sensitivity to blue-light-induced damage.

PURPOSE: Blue-light photooxidative damage has been implicated in the etiology of age-related macular degeneration (AMD). The macular pigment xanthophylls lutein (L) and zeaxanthin (Z) and n-3 fatty acids may reduce this damage and lower the risk of AMD. This study investigated the effects of the lifelong absence of xanthophylls followed by L or Z supplementation, combined with the effects of n-3 fatty acid deficiency, on acute blue-light photochemical damage. METHODS: Subjects included eight rhesus monkeys with no lifelong intake of xanthophylls and no detectable macular pigment. Of these, four had low n-3 fatty acid intake and four had adequate intakes. Control subjects had typical L, Z, and n-3 fatty acid intake. Retinas received 150-µm-diameter exposures of low-power 476-nm laser light at 0.5 mm (∼2°) eccentricity, which is adjacent to the macular pigment peak, and parafoveally at 1.5 mm (∼6°). Exposures of xanthophyll-free animals were repeated after supplementation with pure L or Z for 22 to 28 weeks. Ophthalmoscopically visible lesion areas were plotted as a function of exposure energy, with greater slopes of the regression lines indicating greater sensitivity to damage. RESULTS: In control animals, the fovea was less sensitive to blue-light-induced damage than the parafovea. Foveal protection was absent in xanthophyll-free animals but was evident after supplementation. In the parafovea, animals low in n-3 fatty acids showed greater sensitivity to damage than animals with adequate levels. CONCLUSIONS: After long-term xanthophyll deficiency, L or Z supplementation protected the fovea from blue light-induced damage, whereas adequate n-3 fatty acid levels reduced the damage in the parafovea.

Dietary supplementation: effects on visual performance and occurrence of AMD and cataracts.

OBJECTIVE: To evaluate results of studies that have provided information regarding the effects of dietary supplementation on visual performance, development and progression of age-related macular degeneration (AMD), and risk for cataracts. RESEARCH DESIGN AND METHODS: Studies with information about the effects of dietary supplementation were identified via PubMed searches that combined (in separate searches) the terms 'supplement' OR 'supplementation' OR 'diet' AND 'cataract' or 'macular degeneration' or 'visual' OR 'vision'. Additional references concerned with biologic effects of specific agents, measurement of visual function, and the etiology and epidemiology of cataracts and AMD were identified on the basis of PubMed conventional literature searches. RESULTS: Studies of the effects of dietary supplementation, primarily with preparations including lutein and zeaxanthin, have demonstrated improvements in contrast sensitivity and visual performance under glare conditions that, in some studies, have been correlated with effects of treatment on macular pigment optical density. Results from both observational and prospective interventional studies generally support the conclusion that dietary supplements including these xanthophylls significantly decrease the occurrence of AMD and the development of nuclear lens opacities. However, there is variability in results regarding effects of dietary supplementation that may be related to limitations of long-term observational or interventional studies and which cannot be easily controlled or which may also be related in some studies to other important, yet unrecorded, diet- and lifestyle-related factors that are capable of influencing the risks for AMD and/or cataracts. CONCLUSIONS: The multiple benefits of dietary supplementation support the development and use of these preparations to promote optimal visual function and decrease risk for AMD and cataracts. Increasing understanding of the optimal approach to supplementation will depend upon results from interventional studies that also carefully evaluate and analyze well-established factors for these two conditions.

Xanthophyll accumulation in the human retina during supplementation with lutein or zeaxanthin - the LUXEA (LUtein Xanthophyll Eye Accumulation) study.

The xanthophylls lutein (L) and zeaxanthin (Z) form the macular pigment with the highest density in the macula lutea. We investigated Macular Pigment Optical Density (MPOD) responses to supplementation with identically formulated (Actilease) L or Z (OPTISHARP) or L+Z over 6-12 months using doses of 10 or 20mg/day. MPOD as well as blue light sensitivity in fovea and parafovea were measured monthly by heterochromatic flicker photometry. Average xanthophyll plasma concentrations, analysed monthly by HPLC, increased up to 27-fold. MPOD increased by 15% upon L or L+Z supplementation. Supplementation of Z alone produced similar pigment accumulation in fovea and parafovea, which confounded MPOD measurements. After correction for this, a 14% MPOD increase resulted for Z. Thus, during supplementation with xanthophylls, L is predominantly deposited in the fovea while Z deposition appears to cover a wider retinal area. This may be relevant to health and disease of the retina.

Supplementation with the carotenoids lutein or zeaxanthin improves human visual performance.

BACKGROUND: Macular pigment (MP) is found in diurnal primate species when vision spans a range of ambient illumination and is mediated by cone and rod photoreceptors. The exact role of MP remains to be determined. In this study we investigate two new hypotheses for possible MP functions. OBJECTIVE: As MP absorption coincides partly with that of rhodopsin, MP may reduce rod signal effectiveness in the mesopic range, thus extend the usefulness of cone-mediated vision into the mesopic range. Forward light scatter in the eye can reduce retinal image contrast. If blue light contributes significantly to intraocular scatter, selective blue light absorption by MP could reduce the effects of scatter. DESIGN: We investigated 34 subjects from a carotenoid supplementation trial. The measurements included high mesopic contrast acuity thresholds (CATs), macular pigment optical density (MPOD), wavefront aberrations, and scattered light. The measurements were made after 6 months of daily supplementation with zeaxanthin (Z, OPTISHARP), lutein (L), a combination of the two (C), or placebo (P), and again after a further 6 months of doubled supplementation. RESULTS: The data reveal a trend toward lower CATs in all groups supplemented, with a statistically significant improvement in the lutein group (p = 0.001), although there was no correlation with MPOD. Light scattering in the eye and the root-mean-square wavefront aberrations show decreasing trends as a result of supplementation, but no correlation with MPOD. CONCLUSIONS: The results suggest that supplementation with L or Z increases MPOD at the fovea and at 2.5 degrees , and that supplementation can improve CATs at high mesopic levels and hence visual performance at low illumination.