MR angiography in the follow-up of intracranial aneurysms treated with Guglielmi detachable coils: systematic review and meta-analysis

Introduction The aim of this study was to systematically review published data on the diagnostic performance of magnetic resonance angiography (MRA) compared with digital subtraction angiography as reference standard in the follow-up of intracranial aneurysms treated with Guglielmi detachable coils. Methods A systematic search for relevant studies was performed of the PubMed/MEDLINE and Embase databases. Two reviewers independently assessed the methodological quality of each study. A meta-analysis of the reported sensitivity and specificity of each study was performed. Results The inclusion criteria were met by 16 studies. The studies had moderate methodological quality. Pooled sensitivity and specificity of nonenhanced time-of-flight MRA (TOF-MRA) for the detection of residual flow (within the aneurysmal neck and/or coil mesh) were 83.3% (95% CI 70.3-91.3%) and 90.6% (95% CI 80.4-95.8%), respectively. Pooled sensitivity and specificity of contrast-enhanced MRA (CE-MRA) for the detection of residual flow were 86.8% (95% CI 71.4-94.5%) and 91.9% (95% CI 79.8-97.0%), respectively. All pooled estimates were subject to heterogeneity. There were no statistically significant differences in pooled sensitivity and specificity between TOF-MRA and CE-MRA. Conclusion The results of this study suggest that both TOF-MRA and CE-MRA achieve a moderate to high diagnostic performance. However, the findings should be interpreted with caution because the included studies were of moderate methodological quality and all pooled estimates were subject to heterogeneity. More well-designed studies are required to confirm the current results and MRA at higher field strength (> 1.5 T) needs to be further explored.