Vision Vision is much more complicated because these signals have to be processed into a 3-D image Vision is much more complicated because these signals have to be processed into a 3-D image

Fundus Photograph – Hu Eye Fovea Optic Disk

Blind Spot Find Your “blind spot” Optic Disk Find Your “blind spot” Optic Disk Cover 1 eye with the hand from the same side of your body, i.e., L hand over L eye Cover 1 eye with the hand from the same side of your body, i.e., L hand over L eye Fully Extend your free hand with your index finger pointing upward directly in front of your other eye. Note what ever object your index finger is covering and move your finger just out of the way so you can fix your sight on that object. Fully Extend your free hand with your index finger pointing upward directly in front of your other eye. Note what ever object your index finger is covering and move your finger just out of the way so you can fix your sight on that object. Now wiggle your index finger while slowly moving it to the right, left up and down within your peripheral view. Now wiggle your index finger while slowly moving it to the right, left up and down within your peripheral view. Just to the lateral periphery of your fixed view, you will notice you are “blind” to your wiggling finger. Just to the lateral periphery of your fixed view, you will notice you are “blind” to your wiggling finger. Do the same for your other eye. Do the same for your other eye. Where is your blind spot for your other eye? Where is your blind spot for your other eye? How come you are never aware of your blind spot? How come you are never aware of your blind spot?

Amsler Grid

Normal Pre-convergence Appears Normal to Patient but ….. Crowding, Completion and Fixation “Hide” the Details Vision Loss

The classic “Kaniza Triangle” – one can clearly see a triangle, even though the borders are composed of virtual lines formed by the brain Completion

When viewing this face, we automatically scan it with our fovea to form a complete, clear image. The Amsler grid cannot force fixation on a central point, thereby it cannot prevent the peripheral scanning which may mask a non-foveal defect. This is the actual track of an eye looking at this picture, even though the observer was instructed to stare at a single point on the face Fixation – 1 moment please

SRZ + R + While staring at the yellow cross in the upper box, try to read the middle letter on the right. Now try to do the same thing with the lower box. It is easier with the lower box where the “R” stands alone. The neighboring lines in the Amsler Grid reduce the patient’s ability to isolate and detect visual distortions. Crowding

Can you see which are “popping / pimpling out” of the page and which are “pressing” dimpling / indenting in to the page?

Can you see which are “popping / pimpling out” of the page and which are “pressing” dimpling / indenting in to the page? Does it make a difference in this view?