RT Book, Section A1 Singh, Manpreet A1 Whitfield, Denise A2 Knoop, Kevin J. A2 Stack, Lawrence B. A2 Storrow, Alan B. A2 Thurman, R. Jason SR Print(0) ID 1181038395 T1 Anisocoria T2 The Atlas of Emergency Medicine, 5e YR 2021 FD 2021 PB McGraw-Hill PP New York, NY SN 9781260134940 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1181038395 RD 2024/11/09 AB Anisocoria is a disparity of pupil size. To determine the abnormal pupil, compare pupil sizes in light and dark. It is accentuated in the paretic muscle. If the iris sphincter (or its innervation) is involved, the anisocoria will be increased in bright light. If the iris dilator muscle (or its innervation) is affected, it will be more pronounced in darkness. Up to 20% of normal individuals have physiologic anisocoria of 1 to 2 mm.