Abstract
Purpose:
To determine whether photosensitivity (PS) changes over time, and if so, what factors may be related with the change; furthermore, to determine whether tint density changes over time, all in mTBI.
Methods:
A retrospective analysis of 100 electronic patient records (ages 18-40 years) with mTBI and PS was conducted. All charts were from the clinics of SUNY/Optometry from the years 2004 to 2011. An initial computer query using the ICD-9 diagnostic code of 368.13 was used (i.e., “visual discomfort” including PS). Only charts with documented PS were selected for analysis. Numerous factors were assessed, with key findings reported here.
Results:
50% of the patients reduced in PS over time, with most occurring after year 1 post-injury (43%); 2% increased, and the remainder did not change. 33% of patients who wore tinted lenses decreased in PS, in contrast to 73% for those who did not. 77% of patients who used tint maintained the same tint density over time, while 23% reduced, and none increased. 82% of patients who wore contact lenses (non-tinted) decreased in PS, in contrast to 40% for those who did not. Factors associated with retarding PS reduction were: presence of migraines (25%), loss of consciousness at the time of trauma (29%), and having multiple brain injuries (32%). Factors with equal distribution in PS reduction (~50%) were gender, refractive error, medications, visual field defect type, and type of illumination.
Conclusions:
The findings suggest that neural adaptation to PS is a long-term process, with most occurring after year one. The use of spectacle lens tint inhibited this adaptive process; this may change the way PS is treated clinically (i.e., use of low density tints or no tints). Use of non-tinted contact lenses fostered this adaptive process resulting in decreased PS. This too may change the way PS is treated clinically (i.e., use of non-tinted contact lenses). These findings are promising, as they provide prognostic indicators and initial guidance in the management and treatment of photosensitivity in the clinic population.
Keywords: 742 trauma •
611 neuro-ophthalmology: cortical function/rehabilitation •
718 spectacle lens