Time-of-flight MR angiography at 3T versus digital subtraction angiography in the imaging follow-up of 51 intracranial aneurysms treated with coils

Abstract

Objective: To compare 3D time-of-flight MR angiography (TOF-MRA) at 3 Tesla (3T) with digital subtraction angiography (DSA) for the evaluation of intracranial aneurysm occlusion after endovascular coiling.

Methods: In a prospective study, 51 consecutive patients (25 females, 26 males; median age, 51 years) with 51 saccular aneurysms treated with endovascular coiling underwent simultaneous DSA and 3T TOF-MRA at follow-up. DSA and TOF-MRA images were analyzed independently by two senior neuroradiologists. Findings were assigned to 1 of 3 categories in the Raymond classification: complete obliteration, residual neck or residual aneurysm. Agreement between observers and techniques was evaluated using kappa statistics.

Results: DSA images were not interpretable for one patient. Interobserver agreement was determined as excellent for DSA (kappa=0.86) and TOF-MRA (kappa=0.80). After reaching a consensus, DSA follow-up showed 26 (51%) complete obliterations, 20 (39%) residual necks and 4 (8%) residual aneurysms. TOF-MRA showed 23 (45%) complete obliterations, 22 (43%) residual necks and 6 (12%) residual aneurysms. Comparison between TOF-MRA and DSA showed excellent agreement between the techniques (kappa=0.86). In the four cases that were misclassified, TOF-MRA findings were assigned to a higher class than for DSA.

Conclusion: TOF-MRA at 3T is at least as efficient as DSA for the evaluation of intracranial aneurysm occlusion after endovascular treatment with detachable coils. We suggest that TOF-MRA at 3T might be used as the primary method for imaging follow-up of coiled intracranial aneurysms.