Alteration Of Regional Cerebral Blood Flow In Patients With Parkinson’s Disease Using ¹³N-NH₃ PET/CT

Objective The thesis aims to study the changes of regional cerebral blood flow（r CBF）in Parkinson’s disease（PD）with different severity and clinical classification by using¹³N-NH₃ PET/CT.The thesis is also conducted to analyze the correlation between disease duration and r CBF in PD patients,as well as the correlation between the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale（MDS-UPDRS）and the r CBF.Methods PD patients who met the inclusion criteria and exclusion criteria in the outpatient department or the admitted neurology ward of General Hospital of Ningxia Medical University,Cardiovascular and Cerebrovascular Disease Hospital of Ningxia Medical University,or those recruited through the research group during January 2020 to December 2020 were collected.The basic clinical information of the patients was collected.MDS-UPDRS and H-Y staging were used to evaluate the clinical symptoms and disease severity of the patients,and ¹³N-NH₃PET/CT brain imaging was used to calculate the standardized uptake value ratio（SUVr）of different brain regions.Two samples t test was used to compare the differences of SUVr among PD patients in different groups.The correlation between duration of disease,MDS-UPDRS III motion score,and SUVr was analyzed by Pearson correlation or Spearman rank correlation.Results In the early-stage PD group,the SUVr of straight gyrus,lateral orbital gyrus,the contralateral straight gyrus,the contralateral medial orbital gyrus,bilateral lateral orbital gyrus was higher than the middle and advanced-stage PD group（t values:2.250,2.751,2.865,2.113,2.751,2.491,all P<0.05）;In middle and advanced-stage PD group,the SUVr of the ipsilateral posterior temporal lobe and postcentral gyrus was higher than the early-stage PD group（t values:-2.101,-2.202,all P<0.05）.In the tremor group,the SUVr of ipsilateral putamen was higher than the non-tremor group（t value 2.437,P<0.05）.The MDS-UPDRS III motion score correlated negatively with SUVr in inferior frontal gyrus,anterior orbital gyrus,lateral orbital gyrus,superior parietal gyrus,substantia nigra,cingulate gyrus anterior part,cingulate posterior part（r values:-0.439,-0.435,-0.460,-0.450,-0.442,-0.422,-0.522,all P<0.05）.There was a significant positive correlation between the SUVr of cerebellar and MDS-UPDRS III motor score（r value:0.547,P<0.01）.The course of disease correlated positively with SUVr in the middle and inferior temporal gyrus and cerebellum（r values:0.423,0.464,all P<0.05）.The course of disease correlated negatively with SUVr in the Superior parietal gyrus（r value:-0.468,P<0.05）.Conclusion1.The severity of PD may be closely related to the changes in cerebral blood flow in the orbitofrontal cortex,posterior temporal lobe and postcentral gyrus;the duration of PD disease may be related to the changes of cerebral blood flow in the middle and inferior temporal gyrus,superior parietal gyrus and cerebellum.2.Motor dysfunction may be associated with cerebral blood flow in the inferior frontal gyrus orbitofrontal cortex,superior parietal gyrus,substantia nigra,cingulate gyrus,and cerebellum.3.The pathophysiological changes of PD tremor may be related to increased putamen perfusion.