CTA and DSA Evaluation of Patients with Subarachnoid Haemorrhage

Abstract

We correlate digital subtraction angiography (DSA) and computed tomography with angiographic 3D reconstruction (CTA) in patients with subarachnoid haemorrhage. 45 patients were evaluated with both techniques (CTA and DSA) within 3–4 days after acute haemorrhage: source CT images, MIP and 4D-angio reconstruction and standard DSA were performed and correlated. The MIP tecnique is very easy and quick to perform and operator independent, while 4D-angio reconstruction requires at least 30 minutes to obtain good quality images. CTA and DSA were equivalent in demonstrating the presence of all 57 aneurysms in the 45 patients. Most aneurysms were located at the level of the circle of Willis; CTA was not adequate to demonstrate the neck of aneurysms in 7 cases located in of the syphon, vertebral artery and posterior communicating artery; CTA gave a good display of the thrombus within the aneurysm. Patients could go directly from the CT diagnostic room to the operating room in certain types of aneurysm such as those in the anterior communicating artery or middle cerebral artery in which there is a correlation between site of the haemorrhage and the aneurysm. In the future, improvements in MR technology will also exclude aneurysms in sites difficult to evaluate by CTA such as the syphon, so that DSA will be performed only in selected doubtful cases.