Acquired Disorders that Obscure the Margin of the Optic Disk

 Disorders that Obscure the Margin of the Optic Disk

Acquired Disorders that Obscure the Margin of the Optic Disk

The normal variants and congenital changes discussed in the previous section must be distinguished from abnormal changes to the optic disk due to nervefiber edema. The term optic disk edema is used in a generic sense to describeany such change. However, this term should be further specified whenever possible:

❖ Optic disk edema without primary axonal damage:

–  Papilledema.

–  Hypotension papilledema.

❖ Optic disk edema with direct axonal damage:

–  Inflammation: papillitis or retrobulbar optic neuritis.

–  Infarction with ischemic optic neuropathy (arteriosclerotic or arteritic).

❖ Optic disk edema due to infiltration:

–  For example due to an underlying hematologic disorder.

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