Potential Uses for Precision Tinted Lenses in a Neurology Clinic

Photophobia is a complex disorder that can involve aversion not simply to bright light but to spatial patterns, colour and flicker. The use of tinted lenses to reduce photophobia in neurological diseases has a long history. Rarely has the possibility that different individuals might require lenses individually tailored to their needs been considered. Here we explore this possibility using the Intuitive Colorimeter system. The colorimeter illuminates text with coloured light and permits the colour, strength of colour and brightness to be manipulated separately. Many individuals find that a colour other than white is comfortable for viewing text. This colour is optimized in the colorimeter by a search strategy that allows for colour adaptation. Spectacle lenses are then individually tinted so that the chosen colour is experienced under conventional lighting. In this article, we review the use of the Intuitive Colorimeter in photosensitive epilepsy, autism, migraine, cluster headache, visual snow, stroke, multiple sclerosis and concussion; these are disorders in which individually coloured tints have featured in scientific and clinical reports. The evidence is preliminary rather than conclusive, but it suggests that precision tints can reduce photophobia. In patients with autism, the perception of emotion in facial expression is improved. Occasionally, the clinical benefit extends to the reduction of seizures and headaches and to an increase in reading speed.