Background: The angiogram-negative subarachnoid hemorrhage (SAH) literature includes patients with perimesencephalic hemorrhage, which is recognized to have a much better outcome than aneurysmal SAH.
Objective: To evaluate the clinical outcomes of Nonperimesencephalic Angiogram-Negative SAH (NPAN-SAH).
Methods: A prospective, spontaneous SAH database of 1311 patients that accrued between April 2006 and December 2014 was screened. All patients with NPAN-SAH and 2 consecutive negative cerebral angiograms were included.
Results: We identified 191 (11%) from a total of 1311 patients with spontaneous SAH. Amongst angiogram-negative patients, 83 (4.9%) were adjudicated to have NPAN-SAH. Patient characteristics were similar across the groups, except NPAN-SAH patients were more likely to be men and had higher rates of diabetes. In a multivariable logistic regression model, NPAN-SAH patients were less likely to develop vasospasm, after adjusting for Fisher grade, sex, and diabetes (odds ratio [OR]: 0.197, 95% confidence interval [CI; 0.07-0.55], P = .002). In another adjusted model accounting for Hunt and Hess clinical grade, NPAN-SAH patients were also less likely to develop vasospasm (OR: 0.2, 95% CI [0.07-0.57], P = .002). We found no statistical significance between 2 groups for rebleed, developing hydrocephalus, seizures, or delayed cerebral ischemia. NPAN-SAH patients were equally associated with poor functional outcome (modified Rankin scale ≥3; OR: 1.16, 95% CI [0.615-2.20], P = .6420), and death (OR: 1.22, 95% CI [0.362-4.132], P = .7455) compared to aneurysmal SAH.
Conclusion: Although the risk of vasospasm may be lower, patients with NPAN-SAH are equally associated with delayed cerebral ischemia, poor outcome, and death as compared to patients with aneurysmal SAH. Furthers studies may be necessary to further clarify these findings.
Copyright © 2017 by the Congress of Neurological Surgeons