Supplementary Use of Computed Tomographic Angiography in Subarachnoid Hemorrhage with Negative Digital Subtraction Angiography: Report of a Case

Abstract

With advances of resolution and re-combination techniques in computed tomography (CT), CT angiography (CTA) has frequently been employed to detect intracranial aneurysms. Its advantages, such as being non-invasive and time efficient, as well as the high resolution and 3-dimensional images obtained, have made it the preferred choice for screening patients at high-risk for intracranial aneurysms. Here we report the case of a 57-year-old man whose initial digital subtraction angiography (DSA) was negative. However, a follow-up CTA revealed a neck of intracranial aneurysm on the anterior communicating artery 48 hours later. This aneurysm was clipped successfully through the left sub-frontal approach and the patient made a good recovery following the surgery. In this case, a DSA-missed aneurysm was picked up by CTA and a catastrophe was prevented. We have thus shown DSA-negative pictures in CTA-positive subarachnoid hemorrhage, and the reason for this unusual image presentation was probably intra-aneurysmal thrombosis, which was confirmed by surgery.