title: Contrast Extravasation on Computed Tomography Angiography Imitating a Basilar Artery Trunk Aneurysm in Subsequent Conventional Angiogram-Negative Subarachnoid Hemorrhage: Report of Two Cases with Different Clinical Courses.
abstract: Contrast extravasation on computed tomography angiography (CTA) is rare but becoming more common, with increasing use of CTA for various cerebral vascular diseases. We report on two cases of spontaneous subarachnoid hemorrhage (SAH) in which the CTA showed an upper basilar trunk saccular lesion suggesting ruptured aneurysm. However, immediate subsequent digital subtraction angiography (DSA) failed to show a vascular lesion. In one case, repeated follow up DSA was also negative. The patient was treated conservatively and discharged without any neurologic deficit. In the other case, the patient showed sudden mental deterioration on the third hospital day and her brain CT showed rebleeding. The immediate follow up DSA showed contrast stagnation in the vicinity of the upper basilar artery, suggestive of pseudoaneurysm. Double stents deployment at the disease segment was performed. Due to the frequent use of CTA, contrast extravasation is an increasingly common observation. Physicians should be aware that basilar artery extravasation can mimic the appearance of an aneurysm.
authors.affiliation: Department of Neurosurgery, Medical Research Institute, Pusan National University College of Medicine and Hospital, Busan, Korea.
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Cho
authors.affiliation: Department of Neurosurgery, Medical Research Institute, Pusan National University College of Medicine and Hospital, Busan, Korea.
authors.forename: Hyuk Jin
authors.initials: HJ
authors.lastname: Choi
authors.affiliation: Department of Neurosurgery, Medical Research Institute, Pusan National University College of Medicine and Hospital, Busan, Korea.
authors.forename: Kyoung Hyup
authors.initials: KH
authors.lastname: Nam
authors.affiliation: Department of Neurosurgery, Medical Research Institute, Pusan National University College of Medicine and Hospital, Busan, Korea.
authors.forename: Jae Il
authors.identifier: 0000-0001-9806-8676
authors.initials: JI
authors.lastname: Lee
keywords: Angiogram-negative SAH; Basilar artery; Computed tomography angiography; Contrast extravasation