Department of Neurosurgery, John Radcliffe Hospital, Oxford, UK.
Department of Neuroradiology, John Radcliffe Hospital, Oxford, UK.
Clin Radiol. 2014 Apr;69(4):350-6. doi: 10.1016/j.crad.2013.11.002. Epub 2013 Dec 18.
To assess the efficacy of delayed magnetic resonance imaging (MRI) in identifying a structural cause for angiogram-negative subarachnoid haemorrhage.
All patients presenting with spontaneous subarachnoid haemorrhage who had negative computed tomography (CT) angiography and catheter angiography between 2006 and 2012 were reviewed.
During the 6 year period, 1023 angiograms were performed for a new presentation of subarachnoid haemorrhage. Of these, 242 (23.7%) did not show a cause for the haemorrhage. A second catheter angiogram was performed in 48 patients, and aneurysms were identified in two patients. Of the remaining 240 patients, 131 underwent a subsequent MRI brain. One hundred and five (80.2%) MRI examinations were performed 4 or more weeks after angiography. In two patients, cavernomas were identified as the likely bleeding source. In both patients, the pattern of subarachnoid haemorrhage surrounding a small intraparenchymal haemorrhage on the initial CT suggested the diagnosis. Thirty-nine patients underwent MRI of the cervical spine, none of which identified a cause for the haemorrhage. None of the patients re-presented to our centre during the 6 year study period.
Delayed MRI following angiogram-negative subarachnoid haemorrhage has a low (1.5%) yield and is not routinely necessary. MRI may be useful to characterize the diagnosis in patients with clinical or radiological features of an underlying abnormality such as a cavernoma.
评估延迟磁共振成像（MRI）对识别血管造影阴性蛛网膜下腔出血的结构性病因的疗效。
回顾了 2006 年至 2012 年间所有因自发性蛛网膜下腔出血而出现 CT 血管造影和导管血管造影阴性的患者。
在 6 年期间，对 1023 例新发蛛网膜下腔出血患者进行了 242 例（23.7%）未显示出血原因的血管造影。48 例患者进行了第二次导管血管造影，其中 2 例发现了动脉瘤。在剩余的 240 例患者中，131 例随后进行了脑部 MRI。105 例（80.2%）MRI 检查在血管造影后 4 周或以上进行。在 2 例患者中，海绵状血管畸形被认为是可能的出血源。在这 2 例患者中，初始 CT 上围绕小脑实质内出血的蛛网膜下腔出血模式提示了诊断。39 例患者接受了颈椎 MRI，均未发现出血原因。在 6 年的研究期间，没有患者再次到我们中心就诊。
血管造影阴性蛛网膜下腔出血后延迟 MRI 的检出率较低（1.5%），并非常规需要。对于有潜在异常的临床或影像学特征（如海绵状血管畸形）的患者，MRI 可能有助于明确诊断。
