Magnetic resonance angiography or digital subtraction catheter angiography for follow-up of coiled aneurysms: do we need both?

INTRODUCTION

Endovascular treatment of intracranial aneurysms is now common. Digital subtraction catheter angiography (DSA) is the gold standard for imaging follow-up of coiled intracranial aneurysms; however, it is an invasive procedure with a risk of complications. Time-of-flight magnetic resonance angiography (MRA) is an alternative non-invasive imaging method. In a previous study, we found that MRA at 1.5T was comparable to DSA for detection of aneurysm recurrence in this patient group and subsequently added MRA to the routine follow-up protocol. In the current study, we further compare MRA with DSA to determine whether MRA could safely replace DSA.

METHODS

Patients who had endovascular coiling procedure for intracranial aneurysm from 10/2004 to 6/2010 were identified from our database. A radiologist and a radiology registrar compared MRA and DSA for all patients who received both modalities. DSA was considered as the reference technique. 'Agreement' or 'disagreement' between modalities was noted regarding absence or presence of aneurysm recurrence.

RESULTS

The study group comprised 86 treatments of 80 aneurysms in 73 patients. There were 83/86 agreements between modalities and 3 disagreements. In one case, MRA identified a recurrence that was not seen on the corresponding DSA. In two cases, DSA showed a minor recurrence that was not seen on MRA.

CONCLUSION

Of the two MRA 'misses', neither would have resulted in different management. MRA is a safe and accurate modality for follow-up of coiled aneurysms and can replace DSA.