see also: [[pupil exam]], [[Mydriasis]], [[Diplopia]] #opthal > **Definition:** Unequal pupillary size **causes** - [[pupil exam#Horner Syndrome|horner's syndrome]] - [[Cranial nerve palsies#CN III palsy|CN III palsy]] - physiologic - [[atropine]] - trauma - [[Glaucoma|acute angle glaucoma]] - [[traumatic brain injury#Signs of raised intracranial pressure ( ICP )|elevated ICP]] -- if [[Head trauma radiology#Brain Herniation types|herniation]], unequal and non-reactive pupils