|題名: ||Toward normal perfusion after radiosurgery : Perfusion MR imaging with independent component analysis of brain arteriovenous malformations|
|作者: ||Guo, Wan-you;Wu, Yu-te;Wu, Hsiu-mei;Chung, Wen-yuh;Kao, Yi-hsuan;Yeh, Tzu-chen;Shiau, Cheng-ying;Pan, D. Hung-chi;張玉坤;Chang, Yue-cune;Hsieh, Jen-chuen|
|上傳時間: ||2010-01-28 07:29:41 (UTC+8)|
|出版者: ||American Society of Neuroradiology|
|摘要: ||BACKGROUND AND PURPOSE: Brain perfusion is disturbed by cerebral arteriovenous malformations (AVMs). Our study was conducted to determine the radiosurgical effects on this disturbed perfusion.
METHODS: MR perfusion imaging with independent component analysis was performed in five healthy subjects and 19 patients with AVM before and after radiosurgery (every 6 months up to 2 years). Perfusion map relative cerebral blood volume (rCBV), cerebral blood flow (rCBF), and mean transient time (rMTT) were assessed. Regions of interest (ROIs) on AVM target sections were defined as follows: N, AVM nidus; H, the rest of the ipsilateral hemisphere; P, immediately posterior to the nidus; A, immediately anterior to the nidus; Ar, anterior remote; Pr, posterior remote. Similar ROIs in the contralateral hemisphere (N1, H1, P1, A1, Pr1, and Ar1) served as internal references. Perfusion ratios of ROI–ROI1 were defined. Nonparameteric Mann-Whitney U tests and generalized linear models were used for statistical analysis.
RESULTS: Before radiosurgery, patients’ H/H1 rCBV and rCBF ratios were significantly higher than those of healthy subjects (P < .005), indicating AVM steal. Three types of perilesional perfusion disturbance were observed. From the first postradiosurgical follow-up at 6 months, N/N1 rCBV and rCBF ratios gradually decreased to 1.0 (both P < .001), whereas rMTT ratios gradually increased to 1.0 (P < .015); H/H1, A/A1, and P/P1 rCBV and rCBF ratios decreased after radiosurgery (P < .005), indicating reversal of steal toward normal perfusion.
CONCLUSION: Initial high transnidal flow and perinidal perfusion disturbances were demonstrated. They gradually changed toward normal perfusion after radiosurgery. This explains, in part, the pathophysiologic factors of AVM and therapeutic effects.
|關聯: ||American Journal of Neuroradiology 25(10), pp.1636-1644|