An anopsia is a defect in the visual field. If the defect is only partial, then the portion of the field with the defect can be used to isolate the underlying cause.
|Scheme showing central connections of the optic nerves and optic tracts. (Lesions at different locations relate to different types of anopsias.)|
Types of partial anopsia:
The term anopsia comes from the Ancient Greek ἀν- (an-), "un-" and ὄψις (opsis) "sight".