Corneal topology before LASIK (blind as a bat). The yellow places are elevated ridges across the front of my corneas, the red areas are the "peaks". In "perfect" eyes the entire plane would be blue/green. The crosshairs at the bottom of the chart show why I could never see vertical lines.

And after LASIK (20/15). The yellow-red areas on the front of my corneas are now planar (see the blue/green color now). The outside yellow-red areas are small pools of artificial tears to keep the flaps moist.