This could be caused by a variety of factors, including a migraine aura, an eye muscle problem, or a problem with the blood vessels in your eyes. If your previous medical evaluations haven't found a cause, it would be best to try acupuncture for migraines.
This could be caused by a variety of factors, including a migraine aura, an eye muscle problem, or a problem with the blood vessels in your eyes. If your previous medical evaluations haven't found a cause, it would be best to consult with a neurologist for further evaluation, especially given your history of a concussion and post-concussive syndrome. It may also be helpful to keep a headache diary to track any patterns or triggers.
It is not typical of any specific problem. If you live in a large city with a university I would make an appointment with a neuro-ophthalmologist and make sure you have a peripheral visual field test. If you want to push with with local eye exam see an ophthalmologist that specializes in retina and vitreous. Besides sectoral RD, the problem could be a splitting of the retina which can be very difficulty to see (retinoschesis) and also rule out old peripheral retina vein or artery occlusions