The Study Of MR In The Evalution Of Vessels Responsible For Moyamoya Disease, Cerebral Revascularization After Operation And Cerebral Hemodynamics During The Perioperative Period

Part1The study of Comparison of the diagnostic and postoperative follow-up value of DSA, MRA combining with MRI for Moyamoya disease.Objective:Comparison of the diagnostic and postoperative follow-up value of DSA, MRA combining with MRI for Moyamoya disease.Methods:Twenty-eight patients with Moyamoya disease ascertained by DSA received cerebral revascularization on one side. MRA and MRI were performed for all patients before and after the operation, while DSA was performed after operation for eleven patients. The images of MRA and DSA in visualization of stenosed vessels, Moyamoya vessels, collateral circulation, and cerebral revascularization after operation were compared by three experienced radiologists.Results:The visualization of stenosis in intracervical artery (ICA), middle cerebral artery (MCA), anterior cerebral artery (ACA) and the circle of Willis in MRA of all cases was very similar with DSA. Moyamoya vessels in all cases can be displayed by DSA, while two cases cann’t displayed in MRA. In all cases, the collateral circulation including posterior pericallosal artery(15,2), pial artery(26,2), ophthalmic artery(20,4), middle meningeal artery(10,1) and superficial temporal artery(9,1) was demonstrated on MRA and DSA respectively. Cerebral revascularizations after operation in all cases were well demonstrated on MRA. MR] can demonstrate the cerebral parenchyma that was just not available in DSA.Conclusions:DSA is the gold standard of diagnosing Moyamoya disease. The visualization of main vessels and cerebral revascularization after operation in MRA wasis very similar with DSA, but MRA was below DSA in insignificant Moyamoya vessels and collateral circulation. MRI as an important supplement can provide valuable information of cerebral ischemia and hemorrhage. MRA combining with MRI can be an important method for screening, diagnosis, cerebral revascularization after operation and follow-up of Moyamoya disease.Part 2The clinical value of MRA on stage and classification of Moyamoya disease, and the value of PWI in the cerebral hemodynamics of different classifications of Moyamoya disease.Objective:To evaluate the clinical value of MRA on stage and classification of Moyamoya disease, and explore the value of PWI in the cerebral hemodynamics of different classifications of Moyamoya disease.Methods:According to Suzuki’s vessel stage, twenty-eight patients with Moyamoya disease ascertained by DSA were staged. Stage Ⅰ-Ⅲ were classified as class A, stage Ⅳ-Ⅳ as class B. The reliability of stage and classification of all cases ascertained by MRA was evaluated with DSA as a standard. Perfusion weighted imaging (PWI) were performed for all patients. Perfusion parameters in terminal branches of middle cerebral artery (MCA) on operative side, compared with contralateral side, including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and delay time (DT), as well as relative rate (MCA distribution on operative side/ MCA distribution on contralateral side) of perfusion parameters (rCBF, rCBV, rMTT and rDT) were calculated. Comparisons of the data between different groups were performed using paired Student’s t test.Results:There were 16 patients in Class A, (0 in stage I,5 in stage Ⅱ,11 in stage III), and 12 patients in Class B (9 in stage Ⅳ,2 in stage V, and 1 in stage Ⅵ) for DSA. There were 14 patients in Class A, (1 in stage I,6 in stage Ⅱ,7 in stageⅢ), and 14 patients in Class B (10 in stage Ⅳ,3 in stage V, and 1 in stage VI) for MRA. MTT and DT were sensitive to the change of cerebral hemodynamics. In Class B, rMTT (2.35±0.49) and rDT (2.47±0.51) of MCA distributions on operative and contralateral sides were higher than rMTT (1,48±0.47) and rDT (1.51±0.56) in Class A (t=4.46,4.87, both P<0.05). There were no significant differences in rCBF (0.72±0.16 vs 0.89±0.25) and rCBV(0.75±0.27 vs 1.01±0.32) between classes(t=-1.28,-1.79, both P>0.05).Conclusions:MRA had its limitation in stage of Moyamoya disease. PWI can detect the cerebral hemodynamics of Moyamoya disease.Part 3The value of PWI in assessment of the effect of cerebral revascularization for Moyamoya disease.Objective:To evaluate the value of PWI in assessment of the effect of cerebral revascularization for Moyamoya disease.Methods:Twenty-four patients with moyamoya disease ascertained by DSA received cerebral revascularization on one side. MRA and PWI were performed for all patients before and after the operation. Perfusion parameters in terminal branches of middle cerebral artery (MCA) on operative side, compared with contralateral and cerebellar sides, including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and delay time (DT), as well as relative rate (MCA distribution on operative side/MCA distribution on contralateral side, and MCA distribution on operative side/MCA distribution on cerebellar side) of perfusion parameters (rCBF, rCBV, rMTT and rDT) were calculated. Comparisons of the data between different groups were performed using paired Student’s t test.Results:After operation, rCBF (1.30±0.27) and rCBF (1.26±0.21) of MCA distributions on operative and contralateral sides were higher than rCBF (0.73±0.15) and rCBF (0.98±0.12) before operation significantly (t=-7.19,-6.64, P<0.05). rMTT (1.06±0.20) and rDT (1.07±0.18) after operation were lower than rMTT (1.53±0.34) and rDT (1.40±0.26) before operation (t=5.62,5.40, P<0.05). In MCA distributions on operative and cerebellar sides, rCBF (1.93±0.34) and rCBV (2.25±0.35) were higher than rCBF (0.88±0.18) and rCBV (1.16±0.22) (t=-3.04,-3.06, P<0.05) before operation. rMTT (1.13±0.29) and rDT (1.29±0.12) were lower than rMTT (1.88±0.19) and rDT (3.29±0.47) before operation (t=4.01,4.72, P<0.05).Conclusions:PWI can be an important method for assessment of the effect of cerebral revascularization of Moyamoya disease.