MY CONTENT

The appropriate period of follow-up examinations after endovascular embolization for cerebral aneurysms using time-of-flight MR angiography is not well-known. Between April 2006 and March 2011, one hundred forty-eight unruptured aneurysms were treated with endovascular coil embolization. Among them, the authors investigated 116 unruptured aneurysms, which were followed up for >5 years. Time-of-flight MRA was performed at 1 day, 3–6 months, 1 year after the procedure, and every year thereafter. The mean follow-up period was 7.0 years. Recanalization was observed in 19 (16.3%) aneurysms within 2 years. Among them, retreatment was performed in 8 (6.8%) aneurysms. No recanalization was detected in any aneurysms that had been stable in the first 2 years after embolization. They conclude that aneurysms in which recanalization was not observed within 2 years after endovascular coil embolization were stable during a mean follow-up of 7 years. This result may be helpful in considering the appropriate span or frequency of follow-up imaging for embolized cerebral aneurysms.