The College of Optometrists

what is it that actually causes the distortion in amd and where in the retinal layers does it occur

Good question. I am not sure. It certainly is not unique to the distension of the photoreceptors in the retina by fluid in leaking CNV (wet AMD). I addition, distortion of the retina may occur in dry AMD by underlying drusen and owing to lack of structural support by glial cells. I also suspect that errors in retinal element localisation could occur due to abnormal retinal processing resulting from damage to the inner and outer plexiform layers.

Comments welcome.

Distortion is picked up by the Amsler chart and indicates a 'squiggly' or 'wavy' area on the grid - as described by the Px. There are no missing areas as such. This indicates a wet maculopathy as the retina is raised - due to fluid build up between the RPE and sensory retina. (Im sure its these layers but Kanski will confirm) Fluid leaks and builds up, forming gaps and therefore blood vessels are able to grow towards the retina from the choriocappilaris. This blood can leak and cause further problems. Dry ARMD will show missing portions on the Amsler grid because the photoreceptor outer segments are not being recyled/shed, and therefore function of them are decreased.This leads to missing areas as some receptors are unable to fire responses. Hope this helps.

Any other comments to confirm layers???????