Purpose
Photophobia is a common and debilitating symptom in post-concussion syndrome. Pain sensation to the head, face and eye is transmitted by the trigeminal pathway which gathers input from rhodopsin and melanopsin origins. The melanopsin pathway is related to circadian rhythm and pupillary light response with peak sensitivity at 479nm. Melanopsin sensitive cells have been identified in the retina and the iris making an argument for blocking light from both. Spectacles with amber tint (CPF series) and rose tint (FL-41) limit blue light and are used for photophobia in cone dystrophies, blepharospasm, and migraine headaches. Limitations to wearing sunglasses indoors include cosmetic/social issues and stray light behind the spectacle lens.The purpose of this study was to assess the benefits of wearing tinted prosthetic contact lenses instead of spectacles for photophobia.
Methods
A retrospective observational cohort study was performed on vision rehabilitation clinic records from 5 females and 2 males, ages 24-69 with severe post concusssion photophobia. Subjects were fitted with Orion Biosport soft hydrogel contact lenses 7.5mm central rose/amber/grey (Suntac) tint. Spectrophotometry revealed 20% transmission between 400-640nm and above 640nm 80% transmission. Subjective limitation (SL) scores from 0(none)-4(severe) were attributed to symptoms under various lighting conditions before and after the CL fit. SL scores were also assessed from follow up visit records for night driving, rehab, work, shopping, and the use of electronic devices. Outcome measures were the change in SL scores due to photophobia for various lighting conditions and activities of daily living.
Results
SL score reduction ranged from 20%-80% with CLs. Average SL reduction in fluorescent lighting was 39.14%. A preference for contact lenses over spectacles was reported for work, rehab and social activities. For outdoor sunlight most subjects with CLs still required additional sunlenses.
Conclusions
While wearing dark wrapped sunglasses and hats for photophobia may be tolerable outdoors it is less desirable socially, at work, in rehab and activities of daily living. Prosthetic contact lenses provide enhanced social acceptability with relief from post concussive photophobia. Future studies can determine the ideal tint and diameter of coverage area.