Evaluation of Blood Flow from STA-MCA Bypass by MRA with Off-Sagittal Saturation Pulse

Toshiaki Akashi¹, Toshiaki Taoka¹, Hiroyuki Nakagawa¹, Toshiteru Miyasaka¹, Masahiko Sakamoto¹, Satoru Kitano¹, Satoru Iwasaki², Kimihiko Kichikawa¹

We evaluated the feasibility of MRA with off-sagittal saturation pulse covering STA and bypass point (sMRA) for discrimination between antegrade flow from ICA and bypassed flow from STA. Conventional MRA (cMRA) and sMRA were obtained. sMRA demonstrates only antegrade flow because off-sagittal saturation pulse suppress signal of bypassed flow while cMRA shows both of antegrade and bypassed flow. Subtracting source images of sMRA from those of cMRA was able to give source images and MIP images demonstrating bypassed flow with suppressed antegrade flow in most cases. sMRA is feasible technique for the post-operative assessment of STA-MCA bypass function.