Coronary flow reserve (CFR) has been an indicator used to evaluate coronary microvascular diseases (CMVD), despite its regional heterogeneity and diagnostic inaccuracies. The coronary flow capacity (CFC) map assesses regional size, severity of resting flow, hyperaemic flow, and CFR simultaneously, which may more likely illuminate CMVD. The objective of this study is to clarify the diagnostic, typing, and prognostic value of CFC for CMVD. Patients with a high suspicion of CMVD who underwent rest and adenosine-stress 13 N-ammonia myocardial perfusion imaging (MPI) were included and further classified into three types: type 1, CMVD without obstructive coronary artery disease (CAD) and myocardial diseases; type 2, CMVD in the presence of myocardial diseases; type 3, CMVD co-existing with obstructive CAD. The associations of CMVD types with clinical variables, myocardial blood flow (MBF), CFR, and CFC map were evaluated. Factors predictive of therapy response and prevention of major adverse cardiovascular events (MACE) were also analyzed. A total of 83 patients were diagnosed with CMVD, and there were 40, 16, and 27 patients in types 1, 2, and 3, respectively. Type 2 patients showed the lowest values of MBF and CFR, and the largest CFC areas of dysfunction. The cutoff value of stress MBF between types 1 and 2 was 1.70 mL·min −1 ·g −1 . Severe CFC dysfunction area and CMVD classification were prognostic factors for therapy response, as well as independent predictors of MACE. A severe CFC value of 19.00% was the best cutoff value for therapeutic responses, and patients with higher severe CFC values tended to have a higher incidence of MACE. CFC mapping helps to classify CMVD, and has prognostic value for therapeutic response and MACE.

Background: Phase analysis is a technique used to assess left ventricular mechanical dyssynchrony (LVMD) in nuclear myocardial imaging. Previous studies have found an association between LVMD and myocardial ischemia. We aim to assess the potential diagnostic value of LVMD in terms of myocardial viability, and ability to predict major adverse cardiac events (MACE), using Nitrogen-13 ammonia ECG-gated positron emission tomography (gPET). Methods: Patients with coronary artery disease (CAD) who underwent Nitrogen-13 ammonia and Fluorine-18 FDG myocardial gPET were enrolled, and their gPET imaging data were retrospectively analyzed. Patients were followed up and major adverse cardiac events (MACE) were recorded. The Kruskal-Wallis test and Mann-Whitney U test were performed to compare LVMD parameters among the groups. Binary logistic regression analysis, receiver operating characteristic (ROC) curve analysis, and multiple stepwise analysis curves were applied to identify the relationship between LVMD parameters and myocardial viability. Kaplan–Meier survival curves and the log-rank test were used to look for differences in the incidence of MACE. Results: In total, 79 patients were enrolled and divided into three groups: Group 1 (patients with only viable myocardium, n = 7), Group 2 (patients with more viable myocardium than scar, n = 33), and Group 3 (patients with less viable myocardium than scar, n = 39). All LVMD parameters were significantly different among groups. The median values of systolic phase standard deviation (PSD), systolic phase histogram bandwidth (PHB), diastolic PSD, and diastolic PHB between Group 1 and Group 3, and Group 2 and Group 3 were significantly different. A diastolic PHB of 204.5° was the best cut-off value to predict the presence of myocardial scar. In multiple stepwise analysis models, diastolic PSD, ischemic extent, and New York Heart Association (NYHA) classification were independent predictive factors of viable myocardium and myocardial scar. The incidence of MACE in patients with diastolic PHB > 204.5° was 25.0%, higher than patients with diastolic PHB <204.5° (11.8%), but the difference was not significant. Conclusions: LVMD generated from Nitrogen-13 ammonia ECG-gated myocardial perfusion imaging had added diagnostic value for myocardial viability assessment in CAD patients. LVMD did not show a definite prognostic value.

Dopamine transporter (DAT) and glucose metabolism imaging have been applied in the diagnosis of Parkinson's disease (PD). We explored the possibility of evaluating for PD with NeuroQ software by analyzing 11C-2β-carbomethoxy-3β-(4-fluorophenyl) tropane (11C-CFT) and 18F-FDG PET/CT. We retrospectively analyzed brain 11C-CFT and 18F-FDG PET/CT of 38 patients with parkinsonism, including 20 with PD, 10 with multiple system atrophy (MSA) and 8 with essential tremor (ET), and compared them with the PET/CT of 11 normal healthy controls (NC). PD patients were divided into mild and moderate-severe grade according to the Hoehn-Yahr (H&Y) scale. The 11C-CFT uptake in the caudate nuclei (CN) and putamen (Pu) normalized with cerebellum (CN/Cb and Pu/Cb) were obtained with a manual method and NeuroQ software, and their diagnostic performance was compared.18F-FDG uptake of specific regions was also obtained with NeuroQ, and the enhancement effect for the differential diagnosis was evaluated. There was significant agreement between the manual method and the NeuroQ method for 11C-CFT uptake by CN (r2 = 0.680) and Pu (r2 = 0.770). 11C-CFT uptake by CN and Pu in PD and MSA patients was significantly lower compared to NC and ET patients. The cutoffs of CN/Cb and Pu/Cb for the distinction between PD and NC were 1.71 and 2.20, respectively. No difference in uptake ratios occurred between PD and MSA. 18F-FDG uptake by the pons and cerebellum in the MSA group was markedly decreased. It was highly accurate in distinguishing between PD and MSA when combined with analysis of 11C-CFT uptake. Pu/Cb decreased significantly in mild grade PD compared to NC group (1.92 ± 0.33 vs. 2.82 ± 0.43); however no statistically significant decrease in CN/Cb was observed until moderate-severe grade PD (1.43 ± 0.11 vs. 2.23 ± 0.36). In early asymmetric PD, a statistically significant difference could be seen with Pu/Cb between the symptomatic and asymptomatic side (2.17 ± 0.30 vs. 1.95 ± 0.22). 11C-CFT and 18F-FDG PET/CT can be analyzed quantitatively with NeuroQ software, which provides an accurate method for the diagnosis and severity evaluation of PD.

Objective To assess the diagnostic value of PET/CT in detection of recurrence and metastasis in patients with postoperative colon cancer.Methods A total of 78 patients were suspected with recurrence and metastasis of postoperative colon cancer,including 46 males and 32 females.The diagnostic results of PET/CT and traditional imaging were analyzed and compared with histopathological diagnosis or clinical follow-up data.Results In all 78 patients,recurrence and metastasis were confirmed in 54 patients with histopathological diagnosis or clinical follow-up data.The sensitivity and accuracy of PET/CT were higher than those of traditional imaging in diagnosis of all recurrence and metastasis of postoperative colon cancer,and the sensitivity and accuracy of PET/CT and traditional imaging was 90.74% and 51.85%(P0.01),89.74% and 58.97%(P0.01),respectively.The sensitivity and accuracy of PET/CT were also higher than those of traditional imaging in diagnosis of local recurrence and metastasis of postoperative colon cancer(90.91% vs.42.42%,P0.01;96.15% vs.75.64%,P0.01),respectively.Conclusion PET/CT imaging has significantly higher sensitivity and accuracy than traditional imaging in detection of recurrence and metastasis of postoperative colon cancer.It is an ideal method to monitor the recurrence and metastasis of postoperative colon cancer.

643 Objectives To assess the value of 18F-FDG PET/CT in diagnostic and therapeutic evaluation of malignant lymphoma. Methods The results of 136 18F-FDG PET/CT scans were retrospectively reviewed in 112 patients with pathological diagnosis of malignant lymphoma. All 28 PET/CT scans in 23 cases with Hodgkin’s Disease (HD) were performed after therapy. Among108 PET/CT scans in 89 patients with Non-Hodgkin Lymphoma (NHL), 39 scans were performed before therapy, and 69 scans after therapy. All the patients had corresponding CT, MRI, and/or ultrasound (conventional) images. Results (1) From the 28 PET/CT scans in patients with HD, 7 cases showed normal after chemotherapy and/or radiotherapy, and 8 cases showed improved or partly improved. The other 13 cases were in progresses or recurred after relief. Of 21 cases shown abnormal in PET/CT scans, only 14 cases (66.7%) could reflect the pathogenetic condition on conventional images. (2) From 39 NHL cases performed PET/CT scanning before therapy, 37 cases showed positive, and the accuracy rate was 94.9%. The positive rate was 83.3% from conventional images, but there were 14 cases (46.7%) from positive scans underestimated. (3) From the 69 PET/CT scans of NHL cases after therapy, 30 cases (43.5%) showed normal, and 16 cases (23.2%) improved or partly improved. The other 23 cases (33.3%) were in progresses or recurred after relief. There are only 41 cases (59.4%) could reflect the true situation from conventional images. Conclusions 18F-FDG PET/CT is a sensitive and accurate imaging method in clinical diagnosis, therapy and recurrence evaluation of malignant lymphoma, much more sensitive than conventional imaging methods. Research Support Supported by China National 863 Project 2008AA02Z426