Introduction: In up to 11% of patients who present with subarachnoid hemorrhage (SAH), the origin of the bleed cannot be identified. Cervical spine vascular malformations are known causes of SAH and have been published in several case reports. However, large cohort studies have not found a clear diagnostic benefit in performing cervical spine imaging. There is no clear guideline indicating whether or not cervical spine imaging should be routinely done in these patients. We conducted this retrospective analysis to investigate the diagnostic yield of obtaining cervical spine imaging in patients with digital subtraction angiography (DSA) negative SAH.
Methods: All patients who were admitted to the Mount Sinai Hospital (MSH) for SAH between January 2011 and August 2016 were reviewed. Patients with traumatic etiology were excluded from the study. Patients who had negative findings on initial diagnostic DSA and subsequent cervical spine imaging were identified. The cervical spine imaging results were then analyzed to determine diagnostic yield.
Results: 251 patients were admitted to MSH for SAH over a 5 year period. Forty (16%) had negative findings on initial diagnostic DSA. Twenty-four patients (60%) underwent a second DSA, with none showing positive findings. Fifteen patients (38%) underwent cervical spine magnetic resonance imaging (MRI), and none of them demonstrated positive findings. None of these patients had readmissions due to rebleeding. Compared with SAH DSA-positive patients, DSA-negative patients had lower mean Hunt-Hess grade (2.0 versus 2.8, p<0.00001) and lower modified Fisher score (2.2 versus 3, p<0.001), and higher Glasgow Outcome Score at hospital discharge (4.2 versus 3.1, p<0.00001).
Conclusions: Although cervical spine vascular malformations can cause SAH, it is overall exceedingly rare. The diagnostic yield of MRI cervical spine appears to be low, but our numbers are too small to make definitive conclusions. Further study is warranted to replicate and validate our findings.
Patient Care: Results of our study provide further evidence that can help avoid unnecessary, expansive, and time-consuming scans being done patients with angiographic negative subarachnoid hemorrhage.
Learning Objectives: By the conclusion of this session, participants should be able to discuss why cervical spine MRI should not be ordered in these patients.