Value Of ¹¹C-CFT PET Imaging In The Differential Diagnosis Of Parkinson's Disease And Vascular Parkinsonism

Objective:In this paper,using ¹¹C-Labeled-2-?-carbomethoxy-3-?-?4-fluorophenyl?tropane(¹¹C-CFT)PET/CT imaging,to compare the value of visual analysis and quantitative analysis in ¹¹C-CFT PET/CT imaging in the differential diagnosis of Parkinson's disease and vascular parkinsonism?VP?,and to compare the age,sex,clinical features and brain structural MRI imaging of patients with Parkinson's disease and VP.In order to find a rapid and accurate method to distinguish Parkinson's disease from VP.Method:This study retrospectively analyzed 66 patients who underwent ¹¹C-CFT PET/CT brain imaging because of clinical suspicion of Parkinson's disease from October 2017to October 2019.Brain structural magnetic resonance imaging?MRI?was performed in our hospital within a week before and after ¹¹C-CFT PET/CT imaging.21 patients with Parkinson's disease?9 males,12 females,mean age 60.7±6.7 years?were diagnosed according to clinical diagnostic criteria for Parkinson's disease in China?2016?.According to the diagnostic criteria recommended by Zijlmans,10 patients with VP were diagnosed?8 males and 2 females,mean age 65.7±5.9years?.The remaining patients were patients with Parkinson's superposition syndrome,essential tremor?ET?or no definite clinical diagnosis.Exclusion criteria:1,there is a history of taking anti-dopamine drugs,brain infectious diseases,carbon monoxide or metal poisoning,brain trauma,etc.;2,with symptoms such as hydrocephalus;3,with a tendency of severe coagulation dysfunction.The age,sex,clinical features?including resting tremor,active tremor ankylosis,bradykinesia,gait disorder?,brain structural MRI ischemic imaging findings?including normal,white matter degeneration,lacunar infarction,focal infarction?and visual analysis of ¹¹C-CFT PET imaging were compared and analyzed in Parkinson's disease group and Parkinson's disease group?score standard:0 as normal uptake of bilateral striatum?.1 decreased uptake of bilateral striatum with mild to moderate uniformity,2 focal defects of tracer accumulation in any striatal area or decreased uptake of uniform unilateral striatum.3 the uptake of radioactive tracer in striatum decreased symmetrically or asymmetrically,and the decrease of uptake in putamen was more obvious than that in the caudate nucleus,showing head-end-caudal gradient with or without other irregularly related defects)and quantitative analysis included a striatal binding index,caudate/putamen ratio and striatal asymmetry index?SAI?.T-test was used to compare the age of patients in Parkinson's disease group and VP group.Sex,clinical features,brain structural MRI ischemic imaging findings and qualitative analysis of ¹¹C-CFT PET imaging of patients in Parkinson's disease group and VP group were compared with Fisher's exact test.Wilcoxon rank-sum test was used for the visual score of ¹¹C-CFT PET imaging.In striatum binding index,caudate nucleus/putamen ratio and SAI,the skewness distribution of continuous variables was tested by wilcoxon rank-sum test.The optimal cutoff value determined by ROC curve analysis was used to calculate the visual score of ¹¹C-CFT PET imaging,the binding index of striatum on the opposite side,the ratio of the putamen to putamen on the opposite side of the caudate nucleus,and the sensitivity and specificity of SAI in distinguishing Parkinson's disease and VP group.Using SPSS 22.0 software package to analyze the data,all variables with P<0.05 were considered to have statistical differences.Result:In this study,the age and sex information of the two groups showed that the average age of onset in the VP group was 5.5 years higher than that in the Parkinson's disease group,but there was no significant difference between the two groups?P>0.05?.In the sex ratio,more male patients accounted for about 80%in the VP group,and male patients accounted for about 42.9%in the Parkinson's disease group.The comparison between the two groups was statistically significant.In this study,the clinical characteristics of the two groups showed that the main clinical symptoms were resting tremors in Parkinson's disease group and gait disorder in the VP group.There was a significant difference in clinical symptoms of resting tremor and gait disorder between the two groups.There was no significant difference in clinical symptoms of ankylosis and bradykinesia between the two groups?P>0.05?.In this study,the brain structural MRI ischemic imaging findings results of Parkinson's disease group and VP group showed that 76.2%of the patients in Parkinson's disease group were normal,and the rest of the patients had leukoaraiosis or lacunar cerebral infarction;however,MRI showed cerebrovascular lesions in all patients in VP group,and there was a significant difference between the two groups.The results of the visual score of ¹¹C-CFT PET imaging showed that no patients in the Parkinson's disease group had a score of 0;9.5%of the patients had a score of 1,and the imaging results showed that the distribution of radioactive tracers in the bilateral putamen was moderately reduced and symmetrically distributed;19.0%of the patients had a score of 2,and the results of ¹¹C-CFT PET imaging showed a decrease in uniform uptake of the tracer in the putamen region of the contralateral striatum.71.4%of the patients scored 3 points.The results of ¹¹C-CFT PET imaging showed that the uptake of imaging agents in the bilateral striatum decreased asymmetrically,especially in the bilateral putamen.In the VP group,50%of patients had a score of 0 and ¹¹C-CFT PET imaging was normal.30%of the patients had a score of 1 and the imaging results showed that the distribution of radiotracers on both sides of the nucleus was slightly reduced,and the distribution was symmetrical.10%of patients had a score of 2 and the imaging result was a focal tracer defect in the onset contralateral striatal area.10%of the patients had a score of 3,and the ¹¹C-CFT PET imaging results showed that the imaging agent intake of bilateral striatum was significantly reduced,with an asymmetric distribution,with the bilateral putamen as the focus.The difference in visual score of ¹¹C-CFT PET imaging between Parkinson's disease and VP patients was statistically significant?P<0.05?.The best cut-off value of¹¹C-CFT PET imaging visual score estimated by ROC curve analysis was 3 and area under curve?AUC?was 0.88.The maximum sensitivity and specificity for distinguishing Parkinson's disease from VP patients were 71.4%and 90.0%,respectively.In this study,the contralateral striatum binding index of ¹¹C-CFT PET imaging showed that the striatum binding index of the contralateral striatum in the Parkinson's disease group?1.79⁴.26,2.62±0.71?was lower than that in the VP group?2.05⁴.38,3.39±0.81?.There was a significant difference between the two groups?P<0.05?.The best cut-off value for estimating the contralateral striatum binding index by ROC curve analysis was 3.19,AUC was 0.76,and the maximum sensitivity and specificity for distinguishing Parkinson's disease from VP patients were 70.0%and81.0%,respectively.In this study,the ¹¹C-CFT PET imaging onset of the contralateral caudate/putamen showed that the ratio of the contralateral caudate/putamen?1.07².18,1.66±0.34?in patients with Parkinson disease was higher Patients in the VP group?0.84¹.90,1.33±0.32?,the comparison between the two groups was statistically significant?P<0.05?.The best cut-off value for estimating the putamen-putamen ratio of the contralateral caudate nucleus by ROC curve analysis was 1.42,and the AUC was0.74.The maximum sensitivity and specificity for distinguishing Parkinson's disease from VP patients were 71.4%and 80.0%,respectively.In this study,the SAI results of¹¹C-CFT PET imaging showed that the SAI of patients with Parkinson's disease?2.85²7.81,17.17±6.94?was significantly higher than that of patients with VP?1.20¹7.35,5.73±4.57?,which was statistically significant?P<0.05?.The best cut-off value of SAI estimated by ROC curve analysis was 11.19,and AUC was 0.91.The maximum sensitivity and specificity for distinguishing Parkinson's disease from VP patients were 85.7%and 90.0%,respectively.Conclusion:1.In Parkinson's disease and VP,gender,resting tremor,gait disturbance and ischemic lesions in brain structural MRI ischemic imaging findings have a certain value in the differential diagnosis of the two groups.2.In ¹¹C-CFT PET imaging,visual analysis,contralateral striatum binding index,the ratio of caudate/putamen and SAI are of a certain value in the differential diagnosis between Parkinson's disease and VP.3.In the ¹¹C-CFT PET imaging,quantitative analysis index SAI has the highest accuracy in the differential diagnosis of Parkinson's disease and VP.When the best cutoff value is 11.19,the maximum sensitivity and specificity for distinguishing Parkinson's disease and VP patients are 85.7%and 90.0%,respectively.