Question 2317
{"accessible":true,"alternatives":[{"id":11458,"text":"right middle cerebral artery"},{"id":11459,"text":"right anterior cerebral artery"},{"id":11460,"text":"left atrium"},{"id":11461,"text":"right atrium"}],"archived":false,"correctAlternativeId":11460,"explanation":"\u003cp\u003eThe image shows a hyperdense MCA sign, indicating a clot in the right middle cerebral artery. The thrombus usually does not form in situ, it forms in either the carotid bulb or heart where it contracts, becomes dense, and breaks off to embolize to the intracranial vessels, in this case, the right MCA.\u003c/p\u003e\u003cp\u003eAlthough it is conceivable that the thrombus formed in the right atrium, right-sided thrombi are less common than left-sided thrombi. In addition, for a right atrial thrombus to reach the brain, a right-to-left shunt must be present. Left-sided cardiac thrombi, either from the left atrium or left ventricle, are much more likely to embolize to the brain.\u003c/p\u003e","id":2317,"imageUrl":"https://prod-images-static.radiopaedia.org/images/1985894/aaa871cf1008507f31536f3236b12b_big_gallery.jpg","imageAttribution":{"kind":"case","rID":17958},"imageAttributionCaseInfo":{"title":"Ischemic stroke - hyperdense MCA sign","contributor_name":"Frank Gaillard","contributor_param":"frank","case_rid":17958,"case_param":"ischaemic-stroke-hyperdense-mca-sign"},"firstQuestionPath":"/questions/2591","nextQuestionPath":"/articles/ischaemic-stroke/questions/2311","relatedArticles":[{"id":5242,"title":"Hyperdense MCA sign (brain)","link":"/articles/hyperdense-mca-sign-brain-1?lang=us"},{"id":184109,"title":"Hyperdense vessel sign","link":"/articles/hyperdense-vessel-sign?lang=us"}],"alsoUsedIn":[{"id":1377,"kind":"Course","title":"Head CT: Graphic Novel - page 1377","link":"https://radiopaedia.org/courses/head-ct-graphic-novel/pages/1377"}],"stem":"\u003cp\u003eIn what structure did the intra-arterial clot shown on this CT image most likely\u0026nbsp;form?\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/2317"}],"attemptsPercentages":[{"alternativeId":"11459","percentage":3},{"alternativeId":"11460","percentage":13},{"alternativeId":"11461","percentage":3},{"alternativeId":"11458","percentage":81}],"promptToLogin":false,"questionManager":false,"articleId":"ischemic-stroke"}