Presentation
Right arm/leg paralysis, a right facial droop and fecal incontinence.
Patient Data
Non-contrast CT head (stroke window level 32 HU/ width 8 HU) shows obscuration of the left caudate and lentiform nucleus. There is loss of gray-white matter differentiation in the posterior portion of the left insula cortex and the left superior temporal gyrus. Hyperdense MCA sign is present in the M1 and M2 segments of the left middle cerebral artery. The left frontoparietal cortex maintains normal gray-white differentiation at this stage. No intraparenchymal hemorrhage.
Case Discussion
Stroke window setting is used to optimize visual depiction of subtle loss of gray-white matter differentiation. Window level of 32 Hounsfield unit (HU) and width of 8 HU has been shown to improve sensitivity in detection of acute ischemic stroke on CT. The sensitivity is increased from 57% to 71% compared to normal window setting (level of 20 HU and window width of 80 HU) 1.