Evaluation on Moyamoya Disease Based on Magnetic Resonance Perfusion Weighted Imaging Technology and Hemodynamic Research

This study applied magnetic resonance perfusion weighted imaging (PWI) technology to evaluate the haemodynamic situation of moyamoya disease, including cerebral blood flow (CBF), cerebral blood volume (CBV) and time to peak (TTP), so as to provide an assessment method for clinical treatment of moyamoya disease. A total of 96 hospitalized patients confirmed with moyamoya disease from July, 2013 to July, 2015 were selected; all of them received digital subtraction angiography (DSA) and magnetic resonance perfusion examination. Besides, 30 patients without medical history of nervous system were selected as the normal control group. Then, all cases were divided into groups for comparison. The first group included bilateral moyamoya disease group and normal control group; the second group was for the contrast between the healthy side and the affected side of unilateral moyamoya disease; the third group was for the contrast between sudden onset and chronic onset of moyamoya disease; the fourth group was for the contrast between hemorrhagic and ischemic type of moyamoya disease. Based on mean transit time (MTT) image, scope of abnormal perfusion was classified as region of interest (ROI), and absolute perfusion value of the opposite side was measured and obtained by mirror method. According to ROI area, measurement of the corresponding area of normal control group was carried out. Each ROI area was measured for three times and the mean value was obtained. Values of the corresponding perfusion parameters were recorded and paired sample t test was carried out. Then, CBF, CBV and TTP of the cerebral ischemia area were analyzed and perfusion parameters before and after operation were compared so as to understand the hemodynamic changes. The follow-up studies were performed at certain intervals. The following results can be drawn: statistical significance was found on parameter variation (p < 0.05) between typical moyamoya disease group and normal control group except for relative CBV (rCBV); statistical significance was found on parameter variation (p < 0.05) of the four perfusion parameters between the healthy side and the affected side; statistical significance was found on parameter variation (p < 0.05) of rCBV and relative CBF (rCBF) between acute onset group and chronic onset group; no statistical significance was found on parameter variation (p > 0.05) between hemorrhagic type and ischemic type. Therefore, MRPWI can vividly and intuitively reflect the abnormal perfusion areas and correctly evaluate the cerebral hemodynamics situation of the patients with moyamoya disease, and the sensibility of MTT and TTP is higher than that of CBF and CBV; based on the evaluation of blood vessel compensation of collateral circulation with PWI, the blood perfusion abnormality area can be reflected, which can provide an objective reference for the clinicians in determining the optimal surgical method. In addition, there was no statistically significant difference on blood perfusion between hemorrhagic type and ischemic type.