磁共振灌注成像对脑白质疏松患者脑血流的评价作用

目的 了解能否通过磁共振灌注成像评价脑白质疏松(leukoariosis,LA)患者病灶的血流灌注情况,并用于LA疗效的判断.方法 44例LA患者进行了动态磁敏感对比磁共振灌注成像,其中13例治疗后进行了复查.根据常规磁共振图像确定每例患者最大病灶的感兴趣区(ROI),计算病灶的相对脑血容量(rCBV)、相对脑血流量(rCBF)及相对平均通过时间(rMTT),采用Pearson相关分析法分析以上参数和患者的简易智能状态(MMSE)和日常生活活动能力(ADL)评分的相关性.结果44例LA患者病灶的rCBV(0.797±0.160)和rCBF(0.779±0.164)均减小,而rMTT(1.029±0.073)延长.患者病灶的rCBV与MMSE(r=0.524,P=0.000)和ADL(r=0.621,P=0.000)评分呈显著正相关,rCBF与MMSE(r=0.555,P=0.000)和ADL(r=0.690,P=0.000)评分呈显著正相关,rMTT与MMSE(r=-0.307,P=0.043)和ADL(r=-0.434,P=0.003)评分呈显著负相关.13例复查患者中,有10例病灶区血流灌注增加,并多数伴随着不同程度临床症状改善.结论 磁共振灌注成像可以无创地评价LA患者的脑血流灌注情况,病灶区的血流灌注状态能够在一定程度上客观地反映患者的临床症状,血流灌注的变化可用于疗效的客观评价和监测.

Abstract：

Objective To investigate whether perfusion-weighted imaging (PWI) can be used to evaluate blood perfusion of patients with leukoaraiosis (LA), its relationship to clinical features, and the therapy effect of LA. Methods The 44 patients with LA were recruited in the study. All the subjects were examined with both conventional and dynamic susceptibility contrast-enhanced perfusion MR imaging, 13 of them repeated the examinations after the treatment. The shapes and sizes of the biggest lesions in each patient were confirmed by conventional MR imaging, then the values of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time (rMTT) in each lesion were calculated respectively. Furtherly, a Pearson's correlation analysis was performed to show whether these values were correlated with mini-mental state examination (MMSE)scores or activities of daily living (ADL) scores. Results The 44 lesions of all the subjects showed significant decreases in rCBV (0. 797 ± 0. 160) and rCBF (0. 779± 0. 164) but increase in rMTT (1. 029±0. 073). There were positive correlations between rCBV and MMSE (r = 0. 524, P =0. 000), between rCBV and ADL (r=0. 621, P=0. 000), between rCBF and MMSE (r=0. 555, P=0. 000), and between rCBF and ADL (r= 0. 690, P= 0. 000), and negative correlations between rMTTand MMSE (r=-0.307, P=0.043), and between rMTT and ADL (r=-0.434, P=0. 003). The blood perfusion was enhanced in 10 out of 13 patients who received the repeated examinations after the treatment, most of whom showed the improvement of clinical symptoms.Conclusions Perfusion MR imaging can assess hemodynamic alterations in LA, which could reflect the clinical symptoms. Moreover, the changes of blood perfusions can be used to evaluate and monitor the therapy effect of LA.

Initial investigation of magnetic resonance perfusion-weighted imaging in leukoaraiosis

Objective To investigate whether perfusion-weighted imaging (PWI) can be used to evaluate blood perfusion of patients with leukoaraiosis (LA), its relationship to clinical features, and the therapy effect of LA. Methods The 44 patients with LA were recruited in the study. All the subjects were examined with both conventional and dynamic susceptibility contrast-enhanced perfusion MR imaging, 13 of them repeated the examinations after the treatment. The shapes and sizes of the biggest lesions in each patient were confirmed by conventional MR imaging, then the values of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time (rMTT) in each lesion were calculated respectively. Furtherly, a Pearson's correlation analysis was performed to show whether these values were correlated with mini-mental state examination (MMSE)scores or activities of daily living (ADL) scores. Results The 44 lesions of all the subjects showed significant decreases in rCBV (0. 797 ± 0. 160) and rCBF (0. 779± 0. 164) but increase in rMTT (1. 029±0. 073). There were positive correlations between rCBV and MMSE (r = 0. 524, P =0. 000), between rCBV and ADL (r=0. 621, P=0. 000), between rCBF and MMSE (r=0. 555, P=0. 000), and between rCBF and ADL (r= 0. 690, P= 0. 000), and negative correlations between rMTTand MMSE (r=-0.307, P=0.043), and between rMTT and ADL (r=-0.434, P=0. 003). The blood perfusion was enhanced in 10 out of 13 patients who received the repeated examinations after the treatment, most of whom showed the improvement of clinical symptoms.Conclusions Perfusion MR imaging can assess hemodynamic alterations in LA, which could reflect the clinical symptoms. Moreover, the changes of blood perfusions can be used to evaluate and monitor the therapy effect of LA.