Utility of 3-Dimensional Reconstructions in Multiplanar CT Angiography Negative Spontaneous Subarachnoid Hemorrhage (S23.001)

Abstract

Objective: To determine the utility of 3-dimensional reconstructions in diagnosing vascular malformations in multiplanar CT angiography (CTA) negative spontaneous subarachnoid hemorrhage (SAH). Background Multiplanar CTA is widely used as a first line imaging modality in detecting and characterizing aneurysms in spontaneous SAH. The standard practice in many institutions is to follow up a negative CTA with digital subtraction angiography (DSA). Recently, the yield and utility of this practice has been questioned. We attempted to find whether regular use of 3-dimensional reconstructions in multiplanar CTA negative patients can help avoid the use of DSA in attempts of finding source of hemorrhage. Design/Methods: Retrospective review of consecutive spontaneous SAH cases presenting to a tertiary care hospital from 01/01/2001 to 08/31/2011 was performed. All cases with a known traumatic cause or CTA negative with no follow up DSA were excluded from analysis. Retrospective review of 3-dimensional reconstructions was performed for those cases in which multiplanar CTA was negative but DSA was positive for a vascular malformation. Descriptive statistics were performed to calculate correlation between CTA and DSA in identifying the source of hemorrhage. Results: Of total 547 patients records reviewed, 70 were found to be multiplanar CTA negative. 10 patients were found to have a vascular malformation on DSA. 3-dimensional reconstructions located the source of bleeding in 8 of these 10 cases on retrospective review. Sensitivity of multiplanar CTA was 97.9% with a negative predictive value (NPV) of 85.7%. After retrospective review of the 3-dimensional reconstructions, the sensitivity and NPV increased to 99.6% and 96.8%, respectively. Conclusions: 3-dimensional CTA reconstructions significantly increase the yield in identifying the cause of spontaneous SAH. With the increasing availability of higher resolution scanners and better reconstruction software, there is potential to abolish the practice of immediate DSA in patients with CTA negative spontaneous SAH. Disclosure: Dr. Punia has nothing to disclose. Dr. Jethwa has nothing to disclose. Dr. Gandhi has nothing to disclose. Dr. Prestigiacomo has nothing to disclose.