As stated a couple of posts above this one...nearly all states have a provision for tinted windows for medical necessity. I've been to court twice on a medical re-eval where this was used--and twice I've been sucessfull in getting the driver's license suspended indefinately.
I'm not a doctor--but I'm qualified to testify as an expert in what it takes to safely operate a motor vehicle. I can testify to the hazardous conditions that exist when driving a car at night with dark tinted windows. I can make a compelling argument that in the event your are allowed to have tinted windows due to medical necessity, that a provision is added to your license that your NEVER eligiable to drive during the hours of darkness, and your vehicle is considered "in-operable" (meaning nobody else can drive your car during the hours of darkness either. Perhaps it would be easier to get tint, just not dark tint--just an option.