Disorders in which the Margin of the Optic Disk is Well Defined
Optic Nerve Pits
An optic nerve pit (Fig. 13.17) is characterized by a round or oval grayishdepression in the papillary tissue that does not compromise the margin of the optic disk. These pits are usually found in an inferior temporal location,although they do occur elsewhere. In 85% of all cases, one eye is affected.
Several pits in one optic disk have been described. Serous retinal detachment occurs in 25% of all cases, depending on the location of the pit. Where the detachment affects the macula, a significant loss of visual acuity will result that will prove very difficult to manage with laser surgery. Otherwise optic nerve pits are an incidental finding without any functional deficit. They are considered to be rudimentary colobomas.