MR-angiography evaluation of intracranial aneurysms treated with Guglielmi detachable coils

The aim of the work was to compare digital subtraction angiography (DSA) with magnetic resonance angiography (MRA) in the evaluation of intracranial aneurysms embolized with Guglielmi Detachable Coils (GDC). Forty-nine comparative evaluations were performed in twenty-eight patients with treated intracranial aneurysms by means of 3D Time-of-flight (TOF) MR angiography and digital subtraction angiography studies. The presence and morphology of residual neck and the patency of intracranial vessels were evaluated with both techniques. In patients with complete aneurysm occlusion (36/49), a good resemblance between MR angiography and digital subtraction angiography images was achieved, whereas in partially occluded lesions (13/49) MRA only visualized the residual neck in seven studies. In 24/49 studies (48.9%), a good visualization of intracranial vessels near the aneurysm was not obtained with MRA images. This was due to too small vessel dimensions (below the MRA resolution power) or to turbulent flow related to the presence of GDC In conclusion, MR angiography cannot substitute digital subtraction angiography in the evaluation of GDC treated aneurysms. The resolution of MRA will not visualize the residual aneurysm neck in all cases and can be executed only in cases with major contra-indications to digital subtraction angiography.