Diagnostic evaluation is negative in 10 to 15% of patients with spontaneous SAH; however, the long-term angiographic follow-up in these patients is unknown. In this study, we report the long-term clinical and angiographic follow-up of a cohort of patients with diagnostically negative subarachnoid haemorrhage (DNSAH) enrolled in the Barrow Ruptured Aneurysm Trial (BRAT).Methods
The BRAT study database of patients was analysed for patients with DNSAH. Inclusion criteria were diagnosis of SAH and negative work up, including angiography and MRI of the brain and cervical spine. Follow-up was available at 6 months, one year and three years. Analysis included demographics, clinical course, mRS, and followup imaging studies.Results
No aetiology for SAH could be identified in 56 of 471 (12%) patients enrolled in the BRAT study between March 2003 and January 2007. The mean age for the group with DNSAH was 51 years; 39 (70%) were female. Hydrocephalus required shunting in 4 (7.1%). Clinical symptomatic vasospasm occurred in 4 (7.1%) patients, leading to stroke in one. There were no re-bleeding events. Eleven patients were lost to follow-up and one died of unrelated causes. At one-year, a poor outcome (mRS>2) was present in 4 of 46 (8.7%). At 3-year follow-up, neurovascular imaging was available in 33 and was negative.Conclusion
Hydrocephalus and vasospasm, while infrequent, do occur in DNSAH. Long-term neurologic outcomes are generally good. A thorough evaluation to rule out an aetiology of haemorrhage is necessary, however, imaging beyond 6 weeks from ictus has little utility and re-bleeding is unexpected.Disclosures
A. Elhadi: None. G. A.C. Mendes: None. K. Almefty: None. C. McDougall: None. P. Nakaji: None. R. F. Spetzler: None. J. M. Zabramski: None.