Role of 3D Display MR Angiography in the Study of Intracranial Aneurysms

This paper determines the usefulness of threedimensional (3D) phase-contrast (PC) magnetic resonance (MR) angiography with 3D display in characterizing large intracranial saccular aneurysms. Eight patients referred for non invasive confirmation of unruptured aneurysm (n=9) detected by conventional CT and/or MR imaging were studied by 3D PC (VENC of 20 cm/s, 3 axes) in axial acquisition localised on the circle of Willis using a 0.5 T unit (Vectra, GE). We used 3D display images to assess the feasibility of selective treatment. Results were correlated with catheter angiograms in 3 patients. In two thirds of the cases, location and size of the orifice, size of the sac, and clarification of parent artery were clearly provided allowing prediction of therapeutic management. In the remaining cases results remained doubful because of lack of spatial resolution. The benefit of the method was coupled with the clinical status of the patients to influence the final decision. 3D PC MR angiography with 3D display has emerged as an improvement in predicting therapeutic management, and is especially useful in large unruptured aneurysms in elderly or ill patients.