Prism glasses

[bkennedy]

Does anyone know how prism glasses work and how it relates to MBS? I have several patients who have ‘post concussive syndrome’ which is clearly MBS (one of them just got hit in the head by someone’s elbow at work and has had profound symptoms for 11/2 years now). Several of my patients see the optometrist/OT who give them prism glasses to help with the vision changes and they help some of them. Is this placebo? Is there something to them?

[dschwarz]

I am not an optometrist, but I have extensively worked with people experiencing post-concussion syndrome symptoms. In other words, my expertise is limited in the area of optics, but I would refer people out if oculomotor activities would not improve their coordination. Sensorimotor disruption is common in post-concussion syndrome, and this can cause strabismus (basically where one or both eyes are pointed outside the area of focus). From my understanding, prisms in eyeglasses bend light so that the person can fixate their eye appropriately. In functional neurological symptoms (such as occurring with post-concussion syndrome), the levels of strabismus are generally minimal (compared to a measurable sustained injury to the brain tissue) but can cause some eye strain and difficulty coordinating movement. Successful oculomotor rehabilitation in these cases hopefully will include a gradual reduction in prisms. So, while they can have a placating effect, that effect is a real effect of the physics of optics and how that interacts with their nervous system. Another thing is that even if someone needs prisms, not everyone can tolerate them from what I hear and some do better without them. I hope that explanation helps. -David

[Author]

Posts