Objective:To evaluate the values of 18F-PI-2620 PET/CT brain imaging with SUV ratio (SUVR) in the assessment of tau protein deposition in the brain of patients with different cognitive disorders and its correlation with cognition. Methods:This was a cross-sectional study. From December 2019 to November 2022, a total of 67 subjects including 54 patients with Alzheimer′s disease (AD; 21 males, 33 females, age (68.6±7.8) years), 7 patients with mild cognitive impairment (MCI; 1 male, 6 females, age (63.1±11.2) years) and 6 healthy controls (HC; 4 males, 2 females, age (69.0±5.8) years) were enrolled retrospectively in Renji Hospital. All participants were examined by 18F-PI-2620 PET/CT. SUVRs of brain regions were obtained, including frontal lobe, temporal lobe, occipital lobe, parietal lobe, insular lobe, whole brain, as well as 10 independent brain ROIs (amygdala, orbitofrontal cortex, cingulate gyrus, superior occipital gyrus, superior parietal gyrus, inferior angular gyrus, precuneus, inferior temporal gyrus, entorhinal cortex and parahippocampal gyrus), with inferior cerebellum cortex as the reference region. All participants were estimated by cognitive scales(mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA)). One-way analysis of variance and the least significant difference t test were used to compare the differences of SUVR in each brain region among HC, MCI and AD groups. ROC curve analysis was used to determine the optimal cut-off values of SUVR in each brain region for the differential diagnosis of AD-MCI and AD-HC. Pearson correlation analysis was employed to examine the correlations of SUVR with cognitive scale scores. Results:The SUVR of whole brain was 1.40±0.31 in AD group, 1.08±0.19 in MCI group, and 1.01±0.12 in HC group. SUVR analysis in the whole brain and each brain region could distinguish AD from HC, AD from MCI ( F values: 1.76-10.09, t values: 2.98-7.47, all P<0.05), but could not distinguish HC from MCI ( t values: 0.17-1.53, all P>0.05). ROC curve analysis showed that the best cut-off value of SUVR was 1.18 for whole brain (AUC=0.89), 1.13 for amygdala (AUC=0.94) and 1.26 for parahippocampal gyrus (AUC=0.94) for differential diagnosis of AD and HC, which was 1.06 for whole brain (AUC=0.82), 1.18 for amygdala (AUC=0.88) and 1.28 (AUC=0.88) for infratemporal gyrus to differential diagnosis of AD and MCI. SUVRs of the whole brain, frontal, occipital, parietal, temporal and insula were significantly negatively correlated with MMSE and MoCA cognitive scale scores ( r values: from -0.64 to -0.40, all P<0.05). Conclusions:SUVR quantitative analysis in 18F-PI-2620 PET imaging can assist the differential diagnosis of AD and HC, AD and MCI. The SUVRs of whole brain and five lobes show negative correlations with MMSE and MoCA scores.

Objective:To evaluate the detection rate and distribution characteristics of lesions in patients with biochemical recurrence (BCR) after radical prostatectomy for prostate cancer by 68Ga-prostate specific membrane antigen (PSMA)-11 PET/CT. Methods:From January 2020 to March 2024, 68Ga-PSMA-11 PET/CT examination results of 172 patients (age (69.4±6.5) years) with BCR after radical prostatectomy in Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine were retrospectively analyzed. The relationship between prostate specific antigen (PSA) levels and 68Ga-PSMA-11 PET/CT detection rate was explored. The location and quantity of lesions detected by 68Ga-PSMA-11 PET/CT were analyzed in BCR patients with clear location after local treatment, and data were analyzed by Fisher exact test. Results:The detection rate of 68Ga-PSMA-11 PET/CT in patients with BCR was 70.35%(121/172). The positive detection rate increased with the increase of PSA level, with detection rates of 0.2 μg/L≤PSA<0.5 μg/L, 0.5 μg/L≤PSA<1.0 μg/L, 1.0 μg/L≤PSA<1.5 μg/L and PSA≥1.5 μg/L groups of 49.12%(28/57), 67.24%(39/58), 15/16 and 95.12%(39/41), respectively. After local treatment, 64 cases were diagnosed with 95 recurrent and metastatic lesions. Among them, 22(34.38%) had simple prostate bed recurrence, 23(35.94%) had simple lymph node metastasis, 7(10.94%) had simple bone metastasis, and 12(18.75%) had multi regional metastasis. The proportion of bone metastasis (18.75%, 12/64) was significantly lower than that of prostate bed recurrence and lymph node metastasis (both 50.00%(32/64); both P=0.002). Conclusions:68Ga-PSMA-11 PET/CT has a high detection rate in patients with BCR after radical prostatectomy, especially in patients with high PSA levels. The lesions are mainly distributed in the prostate bed and lymph nodes, while bone metastases are relatively rare, which provide a theoretical basis for the selection of more accurate treatment plans for BCR patients in the future.

Objective:To assess the diagnostic efficiency of 18F-FDG PET for Alzheimer′s disease (AD) in patients with memory impairment. Methods:A retrospective analysis was conducted on 96 patients (40 males, 56 females, age: 69.0(62.8, 74.0) years) initially diagnosed with memory impairment in Renji Hospital, School of Medicine, Shanghai Jiao Tong University between August 2019 and September 2023. The amyloid-tau-neurodegeneration (ATN) criteria, based on 18F-AV45+ 18F-PI-2620 PET/CT+ MRI imaging results, were used as the diagnostic standard for AD. Visual analysis (temporoparietal or posterior cingulate cortex (PCC) hypometabolism) and semi-quantitative analysis methods (PET-SCORE and NeuroQ software analysis (SUV ratio, SUVR)) were applied to evaluate the diagnostic efficiency of 18F-FDG PET imaging for AD. Diagnostic efficiencies of visual assessment and semi-quantitative parameters were compared by χ2 test. Additionally, Pearson correlation analysis was performed to examine the relationship between results of PET-SCORE and cognitive scales. Results:Of the 96 patients initially diagnosed with memory impairment, 61 were clinically diagnosed with AD, while 35 were non-AD patients. Visual assessment of temporoparietal hypometabolism showed the highest sensitivity (91.80%, 56/61), which was significantly different from the sensitivities of PET-SCORE (40.98%(25/61); χ2=29.03, P<0.001) and visual assessment of PCC hypometabolism (77.05%(47/61); χ2=5.82, P=0.016). While semi-quantitative assessment using PET-SCORE demonstrated the highest specificity (100%, 35/35), which was significantly different from the specificities of visual assessment methods (temporoparietal hypometabolism: 17.14%(6/35), χ2=27.03, P<0.001; PCC hypometabolism: 54.29%(19/35), χ2=14.06, P<0.001). PET-SCORE exhibited statistically significant correlations with Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Activities of Daily Living (ADL) scores ( r values: -0.38, -0.36, 0.31, all P<0.01). Conclusions:Among patients initially diagnosed with memory impairment, visual assessment in 18F-FDG PET imaging analysis demonstrates higher sensitivity, while semi-quantitative analysis using PET-SCORE exhibits higher specificity. PET-SCORE shows statistically significant correlation with the severity of cognitive decline.

Objective:To assess the imaging characteristics of muscle FDG metabolism, tumor incidence, and pulmonary interstitial changes in patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody positivity in 18F-FDG PET/CT imaging, and the value of 18F-FDG PET/CT in differentiating anti-MDA5 antibody positive dermatomyositis. Methods:From June 2016 to July 2019, the PET/CT images of 75 patients with dermatomyositis (21 males, 54 females, age (52.3±14.3) years; 34 anti-MDA5 antibody positive and 41 anti-MDA5 antibody negative) and 30 healthy controls (10 males, 20 females; age (53.5±11.8) years) were retrospectively analyzed in Renji Hospital, School of Medicine, Shanghai Jiao Tong University. The SUV max of muscle was measured and the mean of SUV max (mSUV max) was calculated. Statistics of patients with dermatomyositis complicated with neoplastic lesions and the SUV max of pneumonia lesions in patients with dermatomyositis complicated with interstitial pneumonia was determined. Independent sample t test, one-way analysis of variance, Student-Newman-Keuls (SNK) test and χ2 test were used to analyze data. The ROC curve analysis was used to analyze the diagnostic efficacy of mSUV max for the differential diagnosis of anti-MDA5 antibody positive dermatomyositis. Results:The muscle mSUV max of the control group, anti-MDA5 antibody positive and negative groups were 0.39±0.05, 0.66±0.21 and 0.87±0.29 ( F=39.93, P<0.001), respectively. The muscle mSUV max of dermatomyositis patients was increased compared with healthy controls ( q values: 6.76, 12.63, both P<0.001), and the muscle mSUV max of anti-MDA5 antibody negative was higher than positive ( q=5.79, P<0.001). The AUC was 0.74, and the cut-off value of muscle mSUV max was 0.75 with the accuracy of 74.7%(56/75). Of 41 patients with negative anti-MDA5 antibody, there were 6 (14.6%) had malignant tumor, while there was no malignant tumor in patients with positive anti-MDA5 antibody (0/34; χ2=5.41, P=0.020). There were 11 patients (26.8%, 11/41) with anti-MDA5 antibody negative dermatomyositis complicated with interstitial pneumonia and 33 patients (97.1%, 33/34) with anti-MDA5 antibody positive dermatomyositis complicated with interstitial pneumonia ( χ2=37.81, P<0.001). FDG metabolism in anti-MDA5 antibody positive patients was higher than that in anti-MDA5 antibody negative patients (lesion SUV max: 3.65±1.83 and 2.38±1.27; t=2.13, P=0.039). Conclusions:The muscle FDG metabolism of anti-MDA5 antibody positive dermatomyositis patients is higher than that of healthy controls, but lower than that of anti-MDA5 antibody negative patients. The incidence of neoplastic lesions in patients with positive anti-MDA5 antibody is lower than that in patients with negative anti-MDA5 antibody. The proportion and severity of interstitial pneumonia are higher in patients with positive anti-MDA5 antibody than in those with negative anti-MDA5 antibody. 18F-FDG PET/CT has certain value on identifying anti-MDA5 antibody positive dermatomyositis.

Objective:To compare the diagnostic efficacy of 68Ga-prostate specific membrane antigen (PSMA)-11 PET/CT and 18F-fluorodeoxyglucose (FDG) PET/CT in TNM staging before radical prostatectomy. Methods:From July 2018 to December 2019, a total of 67 patients ((67.5±6.8) years) with prostate cancer diagnosed pathologically by radical surgery in Renji Hospital, School of Medicine, Shanghai Jiao Tong University were retrospectively enrolled. All patients underwent 68Ga-PSMA-11 PET/CT and 18F-FDG PET/CT whole-body scans before surgery. Results of PET/CT were compared with pathological diagnosis after surgery to compare the diagnostic efficiencies of 68Ga-PSMA-11 PET/CT and 18F-FDG PET/CT for preoperative TNM staging ( χ2 test). The differences of the maximum standardized uptake value (SUV max) in primary lesions between 2 imaging methods were compared by Mann-Whitney U test. Patients were divided into low-risk, intermediate-risk and high-risk for stratified analysis. Results:Among 67 patients, 9 were with low-risk, 19 were with intermediate-risk, 39 were with high-risk. For T staging, 59 (88.06%, 59/67) patients showed positive results by 68Ga-PSMA-11 PET/CT imaging, with median SUV max of 13.80(7.30, 22.40) for 67 patients; 31(46.27%, 31/67) patients showed positive results in 18F-FDG PET/CT imaging, with median SUV max of 4.00(3.10, 5.60) ( U=62, P<0.05). Stratifed analysis showed that the detection rate of 68Ga-PSMA-11 PET/CT was higher than that of 18F-FDG PET/CT in intermediate-risk patients (17/19 vs 6/19; χ2=4.920, P<0.05). Among 67 patients, 10 were diagnosed as N1 stage based on the pathological results. The sensitivities, specificities, accuracies, positive predictive values and negative predictive values of 68Ga-PSMA-11 PET/CT and 18F-FDG PET/CT for detecting positive regional lymph nodes were 6/10, 87.72%(50/57), 83.58%(56/67), 6/13, 92.59%(50/54) and 4/10, 89.47%(51/57), 82.09%(55/67), 4/10, 89.47%(51/57), respectively. 68Ga-PSMA-11 PET/CT detected 15 patients (22.39%, 15/67) with M1 stage, and 18F-FDG PET/CT identified 9 patients (13.43%, 9/67; χ2=35.436, P<0.05). Conclusions:As for T staging, the detection rate of 68Ga-PSMA-11 PET/CT in the intermediate-risk group is better than 18F-FDG PET/CT. In N and M staging, the detection rates of 68Ga-PSMA-11 PET/CT are higher than those of 18F-FDG PET/CT.

Objective:To evaluate the value of visual analysis and standardized uptake value ratio (SUVR) during 18F-florbetapir (AV45) PET/CT brain imaging in diagnosis of β-amyloid (Aβ) deposition in patients with mild cognitive impairment (MCI) and Alzheimer′s disease (AD), and to explore the clinical ancillary value of the two indexes. Methods:From December 2018 to July 2019, a total of 47 subjects, including 5 (3 males, 2 females, age (58±13) years) normal controls (NC), 8 (2 males, 6 females, age (66±10) years) patients with AD and 34 (16 males, 18 females, age (70±7) years) patients with MCI were enrolled. All subjects underwent 18F-AV45 PET/CT scan. All images were evaluated by visual analysis and SUVR were calculated. The diagnostic efficiencies of visual analysis and SUVR were compared by McNemar test and Kappa test. One-way analysis of variance and Welch test were used to compare data differences. The best threshold value of SUVR was obtained by receiver operating characteristic (ROC) curve analysis. Results:The positive rate of Aβ deposition for all subjects was 46.81%(22/47) by SUVR analysis, and 38.30%(18/47) by visual analysis. There was no significant difference between the two methods ( χ2=33.15, P>0.05), and the consistency was good ( Kappa=0.83). Considering the clinical diagnosis as the"gold standard", the Aβ deposition obtained by visual analysis and SUVR analysis can effectively distinguish AD from NC, and the sensitivities were 7/8 vs 8/8, respectively, both specificities were 5/5( χ2=9.48, P>0.05), with good consistency ( Kappa=0.84). SUVR quantitative analysis could distinguish AD from NC, AD from MCI ( F values: 3.99-8.79, all P<0.01), but could not distinguish NC from MCI (all P>0.05). ROC curve analysis showed that the best threshold value of precuneus′ SUVR was 1.08 for the differential diagnosis of AD and NC; for the differential diagnosis of AD and MCI, the best threshold value of lateral temporal′s SUVR was 1.06. Conclusion:Visual analysis was consistent with SUVR′s qualitative determination during 18F-AV45 PET/CT imaging for brain Aβ deposition, while SUVR quantitative analysis could assist in the differential diagnosis of AD and NC, AD and MCI.

Objective: To investigate the metabolic patterns of ¹¹C-2-beta-carbomethoxy-3-beta-(4-fluorophenyl)tropane (CFT) and ¹⁸F-fluorodeoxyglucose (FDG) PET/CT imaging in patients with tremor and non-tremor Parkinson′s disease (PD). Methods: From March 2018 to March 2019, 28 PD patients (19 tremor patients: 14 males and 5 females, age: (59.9±11.4) years; 9 non-tremor patients: 3 males and 6 females, age: (62.6±9.0) years) were enrolled. For the two groups, the ¹¹C-CFT uptake values in caudate nucleus, anterior putamen and posterior putamen as well as ¹⁸F-FDG uptake values in all brain regions were calculated by regions of interest (ROI) method. Two-sample t test or Mann-Whitney u test were used to analyze the data. Results: Caudate nucleus ¹¹C-CFT uptake in PD patients with tremor was higher than that without tremor (3.03±0.51 vs 2.60±0.62; t=2.687, P<0.05). Yet thalamus glucose uptake of non-tremor PD patients showed more active than tremor patients (1.14±0.05 vs 1.10±0.03; t=3.449, P<0.01). Sorted by modified Hoehn-Yahr stage, tremor patients in advanced stage (stage≥2.5) were characterized by glucose uptake increase in the putamen and cerebellum compared with non-tremor advanced group (1.27±0.04 vs 1.21±0.05, 0.94±0.04 vs 0.86±0.08; t values: 2.695 and 2.492, both P<0.05). Metabolic decrease in the premotor areas was observed in tremor patients in advanced stage compared with early stage (1.07±0.02 vs 1.10±0.03; t=2.053, P<0.05). Conclusion ¹¹C-CFT and ¹⁸F-FDG PET/CT imaging can indicate different metabolic patterns between tremor and non-tremor PD, thus providing information for clinical practice and differential diagnosis.

Objective To validate the quantitative accuracy of 99Tcm-pertechnetate (99 Tcm O4-)SPECT/CT imaging and its influencing factors (sphere size,radioactive concentration,reconstruction methods).Methods National Electrical Manufacturers Association (NEMA) International Electrotechnical Commission (IEC) body phantom with 99TcmO4-solution filled in 6 spheres (diameter:10,13,17,22,28,37 mm) and 1 cylinder (target/background ratio:10∶1) was used to assess the accuracy of uptake quantification.SPECT/CT was used for imaging data acquisition,and volume of interest (VOI) was drawn after the images being corrected and reconstructed.The radioactive concentrations of 6 spheres were measured and compared with the true radioactive concentrations,and quantitative accuracy of each sphere was calculated.The experiment was repeated for 12 times with the same method and different radioactive concentrations.Ordered-subsets expectation maximization (OSEM) reconstruction was performed with 2 or 5 iterations to process imaging data.CT VOI and nuclear medicine (NM) threshold methods were used for the delineation of VOI.Accuracy was compared by paired t test.Results The NM thresholds to get calculated volume close to the true volume were determined to be 40％,40％,50％,70％,80％,90％ for 6 spheres with diameters of 37,28,22,17,13,10 mm,respectively.Comparing 2 methods of VOI delineation (CT VOI and NM threshold),only the accuracy for 17 mm sphere was significantly different (t=5.89,P＜0.01).Five iterations group showed higher accuracy than 2 iterations group (t values:3.19-6.92,all P＜0.05).The average accuracies under 12 different radioactive concentrations were 102％,95％,80％,66％,27％,20％,respectively,for spheres in order from large size to small size.Conclusion The sphere volume and reconstruction method have effect on quantitative accuracy of 99TcmO4-SPECT/CT imaging,and spheres smaller than 17 mm is also significantly affected by partial volume effect.

Objective To compare treatment response according to the PERCIST1.0,RECIST1.1,EORTC,and WHO criteria in patients with colorectal liver metastases (CLM) who received neoadjuvant chemotherapy.Methods A total of 41 CLM patients (27 males,average age 68.48 years;14 females,average age 62.43 years) from January 2010 to September 2013 were included in this retrospective study.PET/CT scan was performed before chemotherapy and after 4-6 cycles′ chemotherapy.The baseline and the sequential follow-up 18F-FDG PET/CT of each patient were evaluated according to the PERCIST1.0,RECIST1.1,EORTC,and WHO criteria.The response was categorized into 4 levels including CR,PR,SD,PD.PET/CT images were used for both metabolic and anatomic evaluation.The concurrent diagnostic CT or MRI images (performed within 1 week of PET/CT) were also utilized when needed.The agreements of criteria were analyzed using Kappa test.The response rate (RR) and disease control rate (DCR) were compared using χ2 test.Results The RR and DCR according to the PERCIST1.0,EORTC and RECIST1.1 criteria were 31.71％(13/41) and 63.41％(26/41),31.71％(13/41) and 60.98％(25/41),17.07％(7/41) and 68.29％(28/41),respectively.The general comparison of PERCIST1.0 and RECIST1.1,EORTC and RECIST1.1 criteria showed good agreements (κ values: 0.711,0.689).Significant difference was not found in the DCR(χ2=2.000,P>0.05) but found in the RR(χ2=6.000,P<0.05) between PERCIST1.0 and RECIST1.1.Difference of DCR between EORTC and RECIST1.1 was not significant(χ2=3.000,P>0.05),while the RR had significant difference(χ2=6.000,P<0.05).The RR and DCR according to WHO criterion were 12.20％(5/41) and 70.73％(29/41),which had a good consistency with those according to PERCIST1.0 criteria (κ=0.629).Significant statistical difference was not found in the DCR(χ2=3.000,P>0.05) but found in the RR(χ2=8.000,P<0.05) between PERCIST1.0 and WHO criteria.Conclusions In evaluating CLM treatment response,anatomical criteria and metabolic criteria have a good consistency.But metabolic criteria are more sensitive for RR evaluating.

Objective To evaluate the predictive value of tumor metabolic indexes measured by 18F-FDG PET/CT in recurrence of stage Ⅰ NSCLC after surgery.Methods A total of 85 patients (44 males,41 females,age (62.46± 10.38) years) in Shanghai Renji Hospital with stage Ⅰ NSCLC,who underwent 18F-FDG PET/CT and subsequent surgical resection,were retrospectively enrolled from April 2006 to December 2011.Gender,age,tumor size,pathology,SUVmax,MTV and TLG of the primary tumor were selected as variables.ROC curve analysis was used to analyze the cut off value.The prognostic significance of parameters for recurrence-free survival (RFS) was evaluated by univariate and multivariate analyses.Survival analysis was analyzed by Kaplan-Meier method.Results During follow-up period,tumor recurrence occurred in 21 patients (24.7％,21/85) and 11 patients (12.9％,11/85) died.The median follow-up period was 44 months.The median values of SUVmax,MTV and TLG were 4.100,3.048 cm3 and 7.970,respectively.Cut off values of SUVmax,MTV and TLG were 7.115,4.701 cm3 and 12.015 according to ROC curve analysis.Univariate Cox analysis showed that SUVmax(x2 =22.091),MTV (x2 =4.941) and TLG(x2 =10.488) were associated with RFS(all P＜0.05).But gender,age,tumor size,and pathology were not independent risk factors of recurrence (x2=0.248-3.888,all P＞0.05).Multivariate Cox analysis revealed that SUVmax(=16.902,HR=15.426,P＜0.05) and TLG (x2=6.029,HR=4.054,P＜0.05) were independent prognostic factors for recurrence.Kaplan-Meier survival analysis showed that the period of RFS in high SUVmax (＞ 7.115) group (x2=32.545,P＜0.05) and in high TLG (＞12.015) group (x2=12.665,P＜0.05) were lower than those in low SUVmax group and low TLG group.Conclusion The SUVmax and TLG measured by 18F-FDG PET/CT have significant value for predicting the recurrence of stage Ⅰ NSCLC.