Andaluz Norberto, Zuccarello Mario
Department of Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0515, USA.
Neurosurgery. 2008 May;62(5):1040-6; discussion 1047. doi: 10.1227/01.neu.0000325865.22011.1f.
Subarachnoid hemorrhage (SAH) is cryptogenic in 15% of cases. Despite reports of proven recurrence, additional diagnostic studies are not often recommended when no abnormalities were identified on the initial study with digital subtraction angiography (DSA). In our retrospective review of outcomes after cryptogenic SAH, we identify diagnostic strategies that most often yielded the source of bleeding.
Of 719 patients admitted with SAH from 1998 to 2003, 92 (12.8%) patients had findings negative for a bleeding source on initial four-vessel DSA. Based on computed tomographic scans, SAH was categorized as perimesencephalic in 45 patients (mean age, 48 yr) and nonperimesencephalic in 47 patients (mean age, 53 yr). All underwent cerebral magnetic resonance imaging and magnetic resonance angiography; select patients underwent additional studies. Multiple variables were analyzed. Outcomes at the time of discharge were categorized according to the modified Rankin Scale.
After perimesencephalic SAH, 44 (97.8%) patients had good scores (0-2) on the modified Rankin Scale, and one patient (2.2%) was deceased. Six (13.3%) patients experienced complications, one (2.2%) experienced vasospasm, and two (4.4%) had hydrocephalus. Further studies in perimesencephalic SAH yielded a diagnosis in 13.9% of patients. After nonperimesencephalic SAH (mean Hunt and Hess score of 2.2), hospital and intensive care unit stays averaged 12 and 8.3 days, respectively. Outcomes were good in 30 (63.8%) patients, poor (modified Rankin Scale 3-5) in 11 (23.4%), and six (12.8%) died. Further studies in nonperimesencephalic SAH exhibited positive findings in 21.3% of patients. Eighteen (38.3%) patients had complications, nine (19.1%) experienced vasospasm, four (8.5%) had recurrent SAH, and 12 (25.5%) had hydrocephalus.
Compared with perimesencephalic SAH, nonperimesencephalic SAH was associated with significantly (P < 0.01) longer hospital and intensive care unit stays, greater complication rates, and worse outcomes. Positive findings after further work-up after initial negative DSA in 16% of our patient population confirms that cryptogenic SAH is not necessarily nonaneurysmal, but that a bleeding risk exists. Therefore, we advocate repeat DSA and/or computed tomographic angiography after cryptogenic SAH.
15%的蛛网膜下腔出血（SAH）病例病因不明。尽管有复发的确切报道，但当初次数字减影血管造影（DSA）检查未发现异常时，通常不建议进行额外的诊断性研究。在我们对原因不明性SAH患者预后的回顾性研究中，我们确定了最常能找到出血源的诊断策略。
在1998年至2003年收治的719例SAH患者中，92例（12.8%）患者初次四血管DSA检查未发现出血源。根据计算机断层扫描，45例患者（平均年龄48岁）的SAH被归类为中脑周围型，47例患者（平均年龄53岁）为非中脑周围型。所有患者均接受了脑磁共振成像和磁共振血管造影检查；部分患者还接受了其他检查。分析了多个变量。出院时的预后根据改良Rankin量表进行分类。
中脑周围型SAH后，44例（97.8%）患者改良Rankin量表评分为0 - 2分，预后良好，1例（2.2%）死亡。6例（13.3%）患者出现并发症，1例（2.2%）发生血管痉挛，2例（4.4%）发生脑积水。对中脑周围型SAH患者进一步检查后，13.9%的患者明确了诊断。非中脑周围型SAH（平均Hunt和Hess评分为2.2）患者的住院时间和重症监护病房停留时间分别平均为12天和8.3天。30例（63.8%）患者预后良好，11例（23.4%）预后较差（改良Rankin量表评分为3 - 5分），6例（12.8%）死亡。对非中脑周围型SAH患者进一步检查后，21.3%的患者有阳性发现。18例（38.3%）患者出现并发症，9例（19.1%）发生血管痉挛，4例（8.5%）再次发生SAH，12例（25.5%）发生脑积水。
与中脑周围型SAH相比，非中脑周围型SAH患者的住院时间和重症监护病房停留时间显著更长（P < 0.01），并发症发生率更高，预后更差。在我们16%的患者人群中，初次DSA检查阴性后进一步检查有阳性发现，这证实原因不明性SAH不一定是非动脉瘤性的，而是存在出血风险。因此，我们主张对原因不明性SAH患者进行重复DSA和/或计算机断层血管造影检查。
