Question 1769
{"accessible":true,"alternatives":[{"id":8787,"text":"A"},{"id":8788,"text":"B"},{"id":8789,"text":"C"},{"id":8790,"text":"D"},{"id":8791,"text":"E"}],"archived":false,"correctAlternativeId":8791,"explanation":"\u003cp\u003eThe\u0026nbsp;\u003cstrong\u003einfarct core\u003c/strong\u003e\u0026nbsp;denotes the part of an\u0026nbsp;\u003ca href=\"https://radiopaedia.org/articles/ischaemic-stroke?lang=gb\"\u003eacute ischemic stroke\u003c/a\u003e\u0026nbsp;which has already infarcted or is irrevocably destined to infarct regardless of reperfusion.\u0026nbsp;\u003c/p\u003e\u003cp\u003eOn\u0026nbsp;CT perfusion\u0026nbsp;the infarct core is defined as the area of the brain with:\u0026nbsp;\u003c/p\u003e\u003col\u003e\u003cli\u003eincreased\u0026nbsp;mean transit time (MTT)\u003c/li\u003e\u003cli\u003emarkedly decreased relative\u0026nbsp;cerebral blood flow (CBF): \u0026lt;30% normal\u003c/li\u003e\u003cli\u003edecreased\u0026nbsp;\u003ca href=\"https://radiopaedia.org/articles/cerebral-blood-volume-cbv?lang=gb\"\u003ecerebral blood volume (CBV)\u003c/a\u003e: \u0026lt;40% normal\u003c/li\u003e\u003c/ol\u003e\u003cp\u003e\u0026nbsp;\u003c/p\u003e","id":1769,"imageUrl":"https://prod-images-static.radiopaedia.org/multiple_choice_questions/262/Slides-for-perfusion-case.key_big_gallery.jpeg","imageAttribution":{"kind":"external","attribution":" AAron S.Field MD, PhD"},"imageAttributionCaseInfo":null,"firstQuestionPath":"/questions/1769","nextQuestionPath":"/articles/ct-brain-perfusion-protocol/questions/1768","relatedArticles":[{"id":24523,"title":"Infarct core","link":"/articles/infarct-core?lang=us"}],"alsoUsedIn":[],"stem":"\u003cp\u003eIn the accompanying\u0026nbsp;graphic, that depicts\u0026nbsp;the changes in cerebral perfusion parameters with progressively decreasing perfusion pressure, which letter best identifies the infarct core?\u0026nbsp;\u003c/p\u003e","menuLinks":[{"text":"Report problem with question","url":"https://docs.google.com/forms/d/e/1FAIpQLSfO3soWYhOjJ7yErSysyCe5V4A1CqW7WK3rDA7MtAkecMGqNw/viewform?entry.1624461248\u0026entry.553583435=https://radiopaedia.org/questions/1769"}],"attemptsPercentages":[{"alternativeId":"8788","percentage":4},{"alternativeId":"8789","percentage":7},{"alternativeId":"8791","percentage":73},{"alternativeId":"8790","percentage":13},{"alternativeId":"8787","percentage":2}],"promptToLogin":false,"questionManager":false,"articleId":"ct-brain-perfusion-protocol"}