<prompt> Which amongst the following is associated with Altitudinal visual field defect:Optic neuritisAION Anterior Ischemic Optic NeuropathyIntracranial tumorPapillitis  <response>: Ans. b AION Anterior Ischemic Optic NeuropathyRef: Harrisons 19th ed. 202 Anterior Ischemic Optic Neuropathy refers to a segmental or generalized infarction of anterior part of the optic nerve It occurs due to occlusion of the short posterior ciliary arteries Visual field defects show typically altitudinal hemianopia involving the inferior commonly or superior half. 