The main characteristic that distinguishes<unk>  is an increase of pupil size with lower light or reduced illumination, such that the pupils differ in size between the two eyes. At any given eye examination, up to 41% of healthy patients can show an anisocoria of 0.4 mm or more at one time or another. It can also occur as the difference between both pupils varies from day to day. A normal population survey showed that during poor light or near dark conditions, differences of 1 mm on average between pupils was found. The presence of physiologic anisocoria has been estimated at 20% of the normal population, so some degree of pupil difference may be expected in at least 1 in 5 clinic patients.
Physiological anisocoria
Mechanical anisocoria
Relative afferent pupillary defect
Ocular dysmetria
Persistent pupillary membrane
Tunnel vision
Scintillating scotoma
Cerebral polyopia