Division of Roles between Three-dimensional Computed Tomography Angiography and Digital Subtraction Angiography in the Diagnosis of Subarachnoid Hemorrhage

Abstract

We summarize our procedure for the diagnosis of the cause of subarachnoid hemorrhage (SAH) and discuss the role of digital subtraction angiography (DSA). From January 2012 to June 2015, 193 patients with nontraumatic SAH were admitted to our institution. All the patients underwent three-dimensional computed tomography angiography (3D-CTA). In 176 (91.2%) of these patients, the cause of SAH was identified by using 3D-CTA. The source of bleeding was detected on DSA on the day of admission in 8 patients (4.1%). However, the origin of the bleeding was unknown in 9 patients (4.7%). Second DSA was performed 4 to 7 days after the onset of SAH in 9 patients with negative angiographic results. Thereby, the cause of SAH was identified in 3 patients. The remaining 6 patients received conservative treatment, as the origin of their SAH was still unknown. Their long-term neurological outcomes were good. Our results showed that most SAH cases could be treated based on 3D-CTA findings alone. However, repeated DSA is necessary for patients with negative results in the initial DSA.