Usefulness of source images from three-dimensional time-of-flight MR angiography after treatment of cavernous dural arteriovenous fistulas

Source images from three-dimensional time-of-flight MR angiography (3D TOF MRA) are useful for the diagnosis of cavernous dural arteriovenous fistulas. The purpose of this study was to assess the accuracy of source images from 3D TOF MRA compared with digital subtraction angiography (DSA) as a follow-up technique for the detection of residual or recurrent fistulas after treatment. We also assessed the effect of embolized materials in the evaluation of MRA.In 14 patients who were treated with embolization and/or radiation therapy, follow-up MRA and DSA were performed after a mean follow-up duration of 3 months. Two observers independently reviewed the source images from MRA in regard to the presence of hyperintense regions within the cavernous sinus and enlargement of the draining veins. They also assessed whether embolized materials affected the evaluation.Sensitivity, specificity, and positive predictive value of source images from MRA in revealing residual or recurrent fistulas were 100% (9 of 9 true positive findings), 80% (4 of 5 true negative findings), and 90% (9 of 10 positive findings), respectively. In all five patients treated with platinum coils, hypointense areas in the cavernous sinus were observed but did not affect image evaluation.Source images from 3D TOF MRA provided accurate diagnosis with no effect of embolized materials in the follow-up of treated cavernous dural arteriovenous fistulas.