Comparison of the image quality between total-body PET/CT with 1 min acquisition and conventional PET/CT: a self-control study / 中华核医学与分子影像杂志

Objective:To investigate whether the image quality of total-body PET/CT (TB PET/CT) with 1 min acquisition can meet the clinical diagnostic requirements.Methods:From May 2019 to September 2021, a total of 90 malignant tumor patients (60 males, 30 females, age 31-86 years) with primary lesions confirmed by pathological diagnosis in Zhongshan Hospital, Fudan University were respectively analyzed. All patients underwent conventional PET/CT (C PET/CT) scan with conventional clinical acquisition and TB PET/CT scan with 1 min acquisition after injecting 18F-FDG in random order. Paired t test or Wilcoxon signed rank test was used to analyze the image quality of these two scans. Results:SUV max of primary lesions in TB PET/CT group was significantly higher than that in C PET/CT group (15.9(7.9, 24.6) vs 12.5(5.8, 16.6); z=8.14, P<0.001), so were signal-to-noise ratio (SNR) of the blood pool, liver, muscles (9.3±3.0, 11.4(9.5, 14.2), 8.3(7.3, 10.1) vs 6.2±1.7, 9.4(7.7, 11.8), 6.0(4.9, 7.1)), tumor-to-blood pool ratio (TBR) (9.3(4.3, 14.8) vs 8.5(4.3, 11.1)), tumor-to-liver ratio (TLR) (6.7(3.0, 10.4) vs 6.1(2.9, 7.7)), tumor-to-muscle ratio (TMR) (23.2(11.5, 38.0) vs 18.3(9.6, 26.6); t=9.36, z values: 4.44-7.40, all P<0.001). Conclusion:The image quality of TB PET/CT scan with 1 min acquisition can meet the diagnostic requirements, and is better than the C PET/CT image quality with conventional clinical acquisition.

Preoperative prediction of lymphovascular and visceral pleural invasion of lung adenocarcinoma based on 18F-FDG PET radiomics / 中华核医学与分子影像杂志

Objective:To evaluate the predictive value of 18F-FDG PET-based radiomics models for lymphovascular invasion (LVI) and visceral pleural invasion (VPI) in lung adenocarcinoma (LAC) prior to surgery. Methods:Eighty-seven patients with LAC (42 males, 45 females, age: (64.6±9.0) years; 90 lesions) pathologically confirmed in the Affiliated Taizhou People′s Hospital of Nanjing Medical University between August 2018 and August 2022 were retrospectively included. Based on the radiomics features extracted from PET images, the machine learning models were constructed by using the support vector machine (SVM), logical regression (LR), decision tree (DT), and K-nearest neighbor (KNN) algorithm. Stratified sampling (Python′s StratifiedkFold function) was employed to divide the data into training set and test set at a ratio of 8∶2. The model stability was assessed using the 50% discount cross-validation. The ROC curve was drawn, and the AUC was calculated to evaluate the value of radiomics models in predicting LVI and VPI in LAC. Delong test was used to compare AUCs of different models.Results:The radiomics models (SVM, LR, DT, KNN) based on PET images showed good predictive value for LVI and VPI in patients with LAC. For LVI, the AUCs were 0.91, 0.90, 0.91, 0.91 in the training set, and were 0.85, 0.87, 0.77, 0.78 in the test set; for VPI, the AUCs were 0.86, 0.86, 0.84, 0.81 in the training set, and were 0.82, 0.80, 0.69, 0.78 in the test set. The F1 scores of the SVM model were the best (0.59 and 0.66 for predicting LVI and VPI respectively). The Delong test showed that there were no significant differences in AUCs among the four models ( z values: from -1.46 to 1.71, all P>0.05). Conclusions:The machine learning models based on 18F-FDG PET radiomics features are effective in predicting LVI and VPI in patients with LAC prior to surgery. These models can assist clinicians in stratifying the risk of LAC and making informed clinical decisions. The SVM model has the best performance in predicting LVI and VPI.

Value of radiomics signatures based on 18F-FDG PET/CT for predicting molecular classification and Ki-67 expression of breast cancer / 中华核医学与分子影像杂志

Objective:To investigate the value of radiomics signatures based on 18F-FDG PET/CT for predicting molecular classification and Ki-67 expression of breast cancer. Methods:A total of 134 female patients ((55.4±13.3) years) who underwent 18F-FDG PET/CT examination and were diagnosed with breast cancer by pathology in the First Affiliated Hospital of Soochow University from April 2016 to May 2023 were retrospectively enrolled. LIFEx software was used to extract radiomics features and the least absolute shrinkage and selection operator (LASSO) algorithm and independent-sample t test were used to screen potentially meaningful features and calculate the radiomics score, which were considered as radiomics models. Clinical characteristics were selected by supervised logistic regression and clinical models were established. Radiomics features and clinical characteristics were incorporated to logistic regression analysis to establish combined models. ROC curves were drawn and the differences among AUCs were analyzed by Delong test. Results:Among 134 patients, 22 were with triple negative breast cancer (TNBC), 47 were human epidermal growth factor receptor 2 (HER2) over-expression type, 37 were Luminal A type and the rest 28 were Luminal B type. The expression of Ki-67 was high in 85 patients, and was low in the rest 49 patients. The AUCs (95% CI) of the combined models for predicting TNBC, HER2 overexpression type, Luminal A type and Ki-67 expression were 0.843(0.770-0.900), 0.808(0.723-0.876), 0.825(0.711-0.908) and 0.836(0.762-0.894), respectively, which were higher than those of clinical models ( z values: 1.97-3.06, all P<0.05). Conclusion:The predictive model combining radiomics signatures based on 18F-FDG PET/CT and clinical characteristics can well predict the molecular classification and Ki-67 expression level of breast cancer.

Diagnostic value of machine learning model based on 18F-FDG PET/CT for polymyalgia rheumatic / 中华核医学与分子影像杂志

Objective:To investigate the diagnostic value of machine learning model based on 18F-FDG PET/CT for polymyalgia rheumatica (PMR). Methods:From November 2014 to December 2022, 177 patients (119 males, 58 females; age: 67.0 ( 61.0, 72.0) years) admitted to the Department of Rheumatology and Immunology, the First People′s Hospital of Changzhou, with suspected PMR and undergoing 18F-FDG PET/CT examination were retrospectively analyzed. Patients were randomly divided into training set and validation set at the ratio of 7∶3. Three machine learning models, including classification and regression tree (CART), the least absolute shrinkage and selection operator (LASSO) algorithm, and logistic regression, were established based on the PET/CT imaging features to aid in the diagnosis of PMR. The diagnostic efficacy of each model was evaluated by ROC curve analysis and differences among AUCs were analyzed by Delong test. Results:There were 78(44.1%, 78/177) PMR patients and 99(55.9%, 99/177) non-PMR patients, and 124 patients in the training set and 53 patients in the validation set. The logistic regression model (training set: AUC=0.961; validation set: AUC=0.930) was superior to the CART (training set: AUC=0.902, z=2.96, P=0.003; validation set: AUC=0.844, z=2.46, P=0.014) in diagnosing PMR, and was similar to LASSO algorithm (training set: AUC=0.957, z=0.95, P=0.340; validation set: AUC=0.930, z=0.00, P=1.000), but with fewer sites evaluated. The simplified PMR-Logit score had the AUC of 0.951 in the overall population, with the sensitivity of 89.74%(70/78) and the specificity of 90.91%(90/99). Conclusion:Machine learning models based on 18F-FDG PET/CT imaging features are expected to be an effective diagnostic tool for PMR.

Prognostic value of 18F-FDG PET/CT combined with clinical staging/scoring system in nasal extranodal natural killer/T-cell lymphoma / 中华核医学与分子影像杂志

Objective:To compare and choose the best method for measuring metabolic tumor volume (MTV) of nasal extranodal natural killer/T-cell lymphoma (ENKTL), evaluate the prognostic value of 18F-FDG PET/CT metabolic parameters and clinical staging/scoring systems for patients with nasal ENKTL, and explore the added value of the two combinations for prognostic prediction. Methods:From January 2016 to September 2022, 44 patients (26 males, 18 females; age (47.5±13.6) years) pathologically diagnosed with nasal ENKTL who underwent 18F-FDG PET/CT imaging before treatment in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively collected. SUV 2.5, SUV 4.0 and 41%SUV max were used as thresholds to measure MTV and total lesion glycolysis (TLG), and the consistency was analyzed by Bland-Altman analysis. The ROC curve analysis was used to compare the prognostic efficiency of different methods and determine the best method. The prognostic values of different clinical factors and clinical staging/scoring systems between groups were evaluated by corrected χ2 test. The independent factors were screened by Cox-regression model, and the combined diagnosis model was constructed by logistic regression. Results:Of 44 patients, 6(13.6%) were dead, with the overall survival (OS) of 32.05(11.77, 64.43) months, and the 2-year and 5-year OS rates of 86.6% and 82.5%, respectively. The mortality of different groups in age (≥60 and <60 years), prognostic index of natural killer cell lymphoma (PINK) score (low- and high-risk), and international prognostic index (IPI) score (low- and high-risk) were significantly different ( χ2 values: 5.02, 4.12, 3.88, all P<0.05). The consistency of MTV measured by different thresholds was good. Among them, the MTV measured by threshold of SUV 2.5 had the highest predictive efficiency with the AUC of 0.737. Multivariate analysis showed that MTV (hazard ratio ( HR)=10.488, 95% CI: 1.864-59.026, P=0.008) was the independent influencing factor of OS. By removing other factors, minimization model was obtained, including MTV and PINK score ( P values: 0.006, 0.048). The prediction model of MTV combined with PINK score improved prognostic efficacy with the AUCs of MTV, PINK score and the combination model of 0.781, 0.741 and 0.912, respectively. Conclusions:MTV measured by threshold of SUV 2.5 has better prognostic predictive value. MTV is the independent prognostic factor for OS in nasal ENKTL patients. MTV combined with PINK score has better prognostic value.

Application of 18F-FDG PET metabolic parameters in evaluating histopathologic grading of soft tissue sarcoma / 中华核医学与分子影像杂志

Objective:To evaluate the value of 18F-FDG PET metabolic parameters in predicting histopathological grade of soft tissue sarcoma (STS). Methods:From December 2012 to December 2021, 51 patients (26 males, 25 females, age range: 32-84 years) who underwent 18F-FDG PET/CT imaging before treatment and confirmed STS pathologically in the First Affiliated Hospital of Dalian Medical University were retrospectively collected. 18F-FDG PET metabolic parameters SUV max, metabolic tumor volume (MTV), total lesion glycolysis (TLG) and intertumoral FDG uptake heterogeneity (IFH) were measured. Kruskal-Wallis rank sum test was used to analyze the differences in metabolic parameters among different groups and Spearman rank correlation analysis was used to analyze the correlation of each metabolic parameter and histological grade. Logistic regression was used to screen and construct the prediction model for high-grade STS. ROC curve was plotted and Delong test was used to analyze the differences among AUCs. Results:The metabolic parameters SUV max, MTV, TLG and IFH were significantly different among French Federation of Cancer Centers Sarcoma Group (FNCLCC)Ⅰ( n=8), Ⅱ( n=10) and Ⅲ ( n=33) grade groups ( H values: 16.24, 10.52, 19.29 and 16.99, all P<0.05), and each metabolic parameter was positively correlated with histological grade ( rs values: 0.58, 0.45, 0.52, and 0.62, all P<0.05). Multivariate logistic regression analysis showed that SUV max(odds ratio ( OR)=1.27, 95% CI: 1.06-1.51, P=0.009) and IFH ( OR=6.83, 95% CI: 1.44-32.27, P=0.015) were independent risk indicators for high-grade STS. The prediction model constructed by combining SUV max and IFH had better diagnostic efficacy for differentiating high-grade STS with the AUC of 0.93, and the sensitivity of 93.9%(31/33) and the specificity of 16/18, respectively. The AUC of prediction model was significant different from SUV max, MTV, TLG and IFH (AUCs: 0.81, 0.78, 0.86 and 0.85; z values: 2.69, 2.53, 1.94 and 1.97, all P<0.05). Conclusions:The metabolic parameters SUV max, MTV, TLG and IFH are valuable predictors for histological grade of STS. The combination of SUV max and IFH may be a more meaningful method than using each of the above metabolic parameters alone.

Prognostic value of baseline 18F-FDG PET/CT metabolic parameters in locally advanced cervical cancer after concurrent chemoradiotherapy / 中华核医学与分子影像杂志

Objective:To explore the prognostic value of baseline 18F-FDG PET/CT metabolic parameters in locally advanced cervical cancer (LACC) after concurrent chemoradiotherapy (CCRT). Methods:From September 2015 to October 2021, the clinical data of 180 LACC patients (age: 22-76 years) who underwent 18F-FDG PET/CT before CCRT at Affiliated Cancer Hospital of Shandong First Medical University were analyzed retrospectively. The metabolic tumor volume (MTV), total lesion glycolysis (TLG), SUV max, and SUV mean were computed by using the margin threshold of 42%SUV max. The optimal threshold for predicting progression-free survival (PFS) was obtained by ROC curve analysis. The Kaplan-Meier method was applied for survival analysis, and the log-rank test was applied to compare the survival rate between groups. Multivariate Cox proportional hazard regression was used to analyze progression for PFS. Results:The median follow-up was 19.1 months, and 54 patients (30.0%, 54/180) suffered from disease progression. ROC curve analysis showed that the optimal cut-off value of MTV was 31.145 ml, with the AUC of 0.641. Para-aortic lymph node (PALN) metastasis had the highest AUC value (0.589) among the clinical factors, followed by International Federation of Gynecology and Obstetrics (FIGO) stage (0.581). The 1-year PFS rates of patients with MTV<31.145 ml ( n=88) and MTV≥31.145 ml ( n=92) were 80.68% and 59.78%, respectively ( χ2=13.72, P<0.001). Multivariate Cox analysis demonstrated that pathological type (hazard ratio ( HR)=3.075, 95% CI: 1.370-6.901, P=0.006), FIGO stage ( HR=1.955, 95% CI: 1.031-3.707, P=0.040), PALN metastasis ( HR=2.136, 95% CI: 1.202-3.796, P=0.010) and MTV ( HR=2.449, 95% CI: 1.341-4.471, P=0.004) were the significant predictors for PFS. Conclusions:Pathological type, FIGO stage, PALN metastasis and MTV are independent prognostic risk factors for PFS. MTV as the baseline 18F-FDG PET/CT metabolic parameter, can realize prognostic stratification analysis.

Value of brain 18F-FDG PET/CT in the preoperative localization of epileptogenic foci in refractory epilepsy patients with negative MRI / 中华核医学与分子影像杂志

Objective:To evaluate the value of 18F-FDG PET/CT for preoperative localization of epileptogenic foci in refractory epilepsy patients with negative MRI. Methods:Clinical data (550 lobes) of 55 epilepsy patients (38 males, 17 females, age (20.0±8.1) years) with negative MRI who underwent preoperative 18F-FDG PET/CT-MRI between January 2014 and June 2020 at the First Affiliated Hospital of Jinan University were retrospectively analyzed. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of 18F-FDG PET/CT, video electroencephalogram (VEEG), PET/CT+ VEEG and PET/CT-VEEG for localizing epileptogenic foci were calculated using stereoelectroencephalography (SEEG) and the outcomes of at least 1 year of postoperative follow-up as reference standards. χ2 test was used to compare the efficiencies of different examination modalities for unilobar, multilobar and all patients. Results:The correct lateralization rate of epileptogenic foci was 92.6%(25/27) using PET/CT. The sensitivity, specificity, accuracy, PPV and NPV of PET/CT for localization of epileptogenic foci were 65.1%(54/83), 77.9%(364/467), 76.0%(418/550), 34.4%(54/157) and 92.6%(364/393), respectively. The sensitivities of PET/CT-VEEG for localization of epileptogenic foci in all patients and patients with multilobar epilepsy were higher than those of VEEG alone (75.9%(63/83) vs 45.8%(38/83), 68.6%(35/51) vs 31.4%(16/51); χ2 values: 15.80, 14.16, both P<0.001). The specificities of PET/CT+ VEEG for localization of epileptogenic foci in all patients and patients with unilobar epilepsy were higher than those of VEEG alone (97.6%(456/467) vs 94.6%(442/467), 97.9%(282/288) vs 94.1%(271/288); χ2 values: 5.66, 5.48; P values: 0.017, 0.019). The sensitivity of PET/CT-VEEG (PET/CT and VEEG concordance) for localization of epileptogenic foci was higher than that of PET/CT+ VEEG (PET/CT and VEEG discordance) (8/9 vs 28.4%(21/74); χ2=10.40, P=0.001), and its specificity and accuracy were higher than those of PET/CT-VEEG (PET/CT and VEEG discordance) (93.4%(57/61) vs 71.7%(291/406), 92.9%(65/70) vs 72.1%(346/480); χ2 values: 13.23, 13.96; both P<0.001). Conclusions:18F-FDG PET/CT can localize and lateralize epileptogenic foci in patients with negative MRI. The combination of 18F-FDG PET/CT and VEEG improves the sensitivity, specificity, and accuracy for epileptogenic foci detection. 18F-FDG PET/CT is more accurate in detecting epileptogenic foci when it is concordant with VEEG.

Clinical value of 18F-FDG PET/MR in localizing epileptogenic foci in refractory epilepsy / 中华核医学与分子影像杂志

Objective:To analyze the clinical value of 18F-FDG PET/MR for precise localization of epileptogenic foci in patients with refractory epilepsy. Methods:From February 2019 to December 2021, 81 patients (52 males, 29 females; age (30.0±10.9) years) with refractory epilepsy confirmed in Ruijin Hospital Shanghai Jiao Tong University School of Medicine were retrospectively enrolled. All patients underwent preoperative PET/MR exam, and the possible position of the epileptogenic foci were determined by PET/MR imaging and pre-surgical evaluation, then the stereoelectroencephalography (SEEG) electrodes were implanted. Surgery was performed, and outcome was assessed by using a modified Engel classification two years after surgery. χ2 test was used to compare the detection rates of MRI and PET/MR fusion imaging in localizing epileptogenic foci and the detection rates of epileptogenic foci in temporal lobe epilepsy (TLE) and extratemporal lobe epilepsy (ETLE) by PET/MR. Results:MRI correctly localized seizure foci in 38 patients, with the detection rate of 46.91%(38/81), while PET/MR detected seizure foci in 73 patients, with the detection rate of 90.12%(73/81; χ2=35.05, P<0.001). There were 63 TLE and 18 ETLE patients. The detection rate of PET/MR in localizing seizure foci in TLE patients was 95.24%(60/63), which was significantly higher than that in ETLE patients (13/18; χ2=5.94, P=0.015). After 2 years follow-up, the postoperative efficacy rate of TLE patients with Engel grades Ⅰ-Ⅱ was 76.19%(48/63), which was 13/18 of ETLE patients ( χ2=0.12, P=0.731). Conclusion:Hybrid PET/MR imaging can accurately locate epileptogenic foci, especially for MRI negative lesions, which provides precision imaging information for surgical planning and improves surgical success rate.

Role of 18F-FDG PET in the preoperative evaluation of extratemporal lobe epilepsy / 中华核医学与分子影像杂志

Objective:To analyze the application value of 18F-FDG PET in the preoperative evaluation of patients with extratemporal lobe epilepsy (ETLE) and explore improved methods to enhance its localization accuracy. Methods:A total of 41 patients (25 males, 16 females, age (22.7±7.5) years) who underwent surgery and ultimately confirmed ETLE in Peking Union Medical College Hospital between January 2006 and November 2022 were enrolled. The accuracy of preoperative independent 18F-FDG PET imaging and the combined application of 18F-FDG PET and MRI in detecting epileptogenic foci and their impacts on treatment decisions were retrospectively analyzed by using visual and semi-quantitative methods. Fisher′s exact test was used to analyze the data. Results:In all 41 patients, 40 cases were found metabolic abnormalities in extratemporal lobe by independent 18F-FDG PET based on visual analysis. Among them, 26 showed unifocal metabolic abnormalities, which were localized as epileptogenic foci. Fourteen patients showed multifocal metabolic abnormalities, and the epileptogenic foci were further verified in 8 cases through semi-quantitative analysis. In 1 case with negative PET visual analysis, a micro-metabolism focus was found at the abnormal MRI signal area. Among 13 patients with negative independent MRI, 9 were found microstructures abnormalities in brain regions with hypometabolism. 18F-FDG PET improved clinical decision-making in 18 patients (43.9%, 18/41). There were 30 patients (73.2%, 30/41) with seizure-free postsurgery, and the prognosis was not significantly different between patients with unifocal 18F-FDG PET metabolic pattern and those with multifocal ones (73.1%(19/26) vs 10/14, P=1.000). Conclusions:18F-FDG PET can be a useful diagnostic tool for patients with ETLE. Semi-quantitative analysis helps to detect more epileptogenic foci with multifocal metabolic abnormalities. The combined evaluation of 18F-FDG PET and MRI can improve the accuracy in localizing epileptogenic foci outside the temporal lobe.

Optimization of 18F-FDG PET/CT semi-quantitative diagnostic model for children with autoimmune encephalitis with epilepsy and negative MRI / 中华核医学与分子影像杂志

Objective:To investigate the value of 18F-FDG PET/CT imaging in the diagnosis of suspected autoimmune encephalitis (AE) in children with epilepsy and negative MRI. Methods:From May 2019 to August 2022, 94 suspected AE children (49 males, 45 females; age 1-15 years) with epilepsy and negative MRI who underwent brain 18F-FDG PET/CT imaging at Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine were retrospectively analyzed. All patients were divided into AE and non-AE groups based on clinical final diagnosis. The effectiveness of visual diagnosis was evaluated. The cortical lesion extent score (S), and SUV max, SUV mean and minimum of SUV (SUV min) of cortical lesions (L), basal ganglia (B) and thalamus (T) were measured and SUV ratios (SUVR) of L/B or L/T were obtained. Independent-sample t test or Mann-Whitney U test was used to analyze data. Binary logistic regression analysis was used to screen the diagnostic factors of AE, and a diagnostic model was established. The diagnostic efficiency was evaluated by ROC curve analysis and Delong test. Results:There were 53 cases in AE group and 41 cases in non-AE group. Based on visual analysis, the sensitivity, specificity and accuracy of 18F-FDG PET/CT for AE were 100%(53/53), 43.9%(18/41) and 75.5%(71/94), respectively. Differences of LSUV max, LSUV mean, LSUV min, L/BSUVR max, L/BSUVR mean, L/BSUVR min, L/TSUVR max, L/TSUVR mean, L/TSUVR min and S between AE and non-AE groups were statistically significant ( z=-6.74, t values: from -8.51 to -3.97, all P<0.001). ROC curve analysis showed that the AUC of L/BSUVR max was the highest (0.914) among visual analysis and semi-quantitative parameters. Logistic regression analysis showed that S (odds ratio ( OR)=11.40, 95% CI: 2.18-59.52, P=0.004), L/BSUVR max( OR=13.19, 95% CI: 2.11-82.51, P=0.006) and L/TSUVR max( OR=9.66, 95% CI: 1.57-59.55, P=0.015) were independent diagnostic factors for AE. Regression model was established: P=1/(1+ e - x), x=2.433×S+ 2.580×L/BSUVR max+ 2.267×L/TSUVR max-3.802. The AUC of this model was 0.948, with the sensitivity, specificity and accuracy of 98.1%(52/53), 90.2%(37/41) and 94.7%(89/94), respectively. The diagnostic efficacy of the optimized scoring system was consistent with the pre-optimization model, and were both superior to L/BSUVR max(both z=2.01, both P=0.040). Conclusion:The diagnostic model and scoring system based on the semi-quantitative analysis of 18F-FDG PET/CT have better diagnostic efficacy for AE and are superior to semi-quantitative parameters alone.

Deep neural networks analysis of 18F-FDG PET imaging in postoperative patients with temporal lobe epilepsy / 中华核医学与分子影像杂志

Objective:To predict the short-term postoperative recurrence status of patients with refractory temporal lobe epilepsy (TLE) by analyzing preoperative 18F-FDG PET images and patients′ clinical characteristics based on deep residual neural network (ResNet). Methods:Retrospective analysis was conducted on preoperative 18F-FDG PET images and clinical data of 220 patients with refractory TLE (132 males and 88 females, age 23.0(20.0, 30.2) years)) in the First Affiliated Hospital of Jinan University between January 2014 and June 2020. ResNet was used to perform high-throughput feature extraction on preprocessed PET images and clinical features, and to perform a postoperative recurrence prediction task for differentiating patients with TLE. The predictive performance of ResNet model was evaluated by ROC curve analysis, and the AUC was compared with that of classical Cox proportional risk model using Delong test. Results:Based on PET images combined with clinical feature training, AUCs of the ResNet in predicting 12-, 24-, and 36-month postoperative recurrence were 0.895±0.073, 0.861±0.058 and 0.754±0.111, respectively, which were 0.717±0.093, 0.697±0.081 and 0.645±0.087 for Cox proportional hazards model respectively ( z values: -3.00, -2.98, -1.09, P values: 0.011, 0.018, 0.310). The ResNet showed best predictive effect for recurrence events within 12 months after surgery. Conclusion:The ResNet model is expected to be used in clinical practice for postoperative follow-up of patients with TLE, helping for risk stratification and individualized management of postoperative patients.

Comparison of Al 18F-NOTA-FAPI-04 and 18F-FDG PET/CT in evaluating patients with initial gastric cancer / 中华核医学与分子影像杂志

Objective:To compare Al 18F-1, 4, 7-trizacyclononane-1, 4, 7-triacetic acid (NOTA)-fibroblast activation protein inhibitor (FAPI)-04 PET/CT with 18F-FDG PET/CT in the evaluation of patients with initial gastric cancer. Methods:Twenty patients (13 males, 7 females, age: 27-77 years) with histologically proven gastric cancer were recruited prospectively between March 2021 and July 2022 in the First Affiliated Hospital of Zhengzhou University. Each patient underwent both 18F-FDG and Al 18F-NOTA-FAPI-04 PET/CT within one week. SUV max, tumor background ratio (TBR) and positive detection rate of the two methods were compared (Wilcoxon signed rank sum test, McNemar χ2 test). Results:Al 18F-NOTA-FAPI-04 showed higher SUV max and TBR than those of 18F-FDG in primary tumors (10.2(8.0, 13.7) vs 5.2(3.3, 7.7), z=-3.47, P=0.001; 7.6(5.6, 10.3) vs 2.4(1.8, 3.0), z=-3.85, P<0.001). For the detection of primary gastric cancer, the positive detection rate of Al 18F-NOTA-FAPI-04 PET/CT showed the trend of being higher than that of 18F-FDG PET/CT (95%(19/20) and 75%(15/20); χ2=2.25, P=0.125). For assessing lymph node metastasis, the detection rate of Al 18F-NOTA-FAPI-04 PET/CT was higher than that of 18F-FDG PET/CT (78.9%(101/128) vs 64.8%(83/128); χ2=13.47, P<0.001). The SUV max and TBR of Al 18F-NOTA-FAPI-04 in lymph node were higher than those of 18F-FDG (5.3(3.5, 9.2) vs 2.8(1.8, 4.7), z=-7.31, P<0.001; 4.6(2.6, 6.5) vs 1.7(1.0, 3.0), z=-8.44, P<0.001). For the detection of peritoneal carcinomatosis, Al 18F-NOTA-FAPI-04 PET/CT showed higher peritoneal cancer index (PCI), SUV max, and TBR compared to 18F-FDG PET/CT (PCI: 12.0(3.0, 29.8) vs 5.5(0.5, 17.5), z=-2.22, P=0.026; SUV max: 8.2(4.4, 12.5) vs 2.7(1.9, 4.0); z=-2.52, P=0.012; TBR: 5.1(2.9, 13.3) vs 1.1(0.9, 2.0); z=-2.52, P=0.012). Conclusion:Al 18F-NOTA-FAPI-04 PET/CT outperforms 18F-FDG PET/CT in primary and metastatic lesions of gastric cancer and might be a potential novel modality for imaging patients with gastric cancer.

Progress on Cerebral Glucose Metabolism Patterns of PET Imaging in Parkinson's Disease / 中国医学影像学杂志

Parkinson's disease(PD)is a common neurodegenerative disease,which seriously affects the quality of life of patients.The early and accurate diagnosis of PD is still a major medical problem.Positron computed tomography(PET)can be used to monitor noninvasively the pathophysiological changes in the early stage of PD in vivo,which has good clinical application value.18F-FDG PET cerebral glucose metabolism imaging is the most convenient and widely used detection method.At present,a variety of specific cerebral metabolic patterns of PD have been found,which have good guidance for the early diagnosis,differential diagnosis,disease monitoring and curative efficacy judgment of PD.Therefore,this paper focuses on the review of the 18F-FDG PET cerebral glucose metabolism model related to PD,aiming to enable a better application of this technique to the diagnosis of PD.

The value of 18 F ⁃FDG PET/CT dynamic imaging in the diagnosis of primary hepatocellular carcinoma with liver metastases / 安徽医科大学学报

Objective @#To explore the value of 18 F ⁃FDG PET/CT dynamic imaging in the diagnosis of primary liver cancer and liver metastases.@*Methods @#In this study , the data of 94 patients with hepatic malignant lesions [hepatocellular carcinoma group (25 cases) , cholangiocellular carcinoma group (27 cases) , and liver metastases group (42 cases)] imaged by whole⁃body dynamic 18 F ⁃FDG PET/CT were used as the research subjects , and the methods of (ANOVA) and subjects ′ working characteristic curves (ROC) were applied to examine the patients with liver malignant tumours of different pathological types SUV max , MRFDG , TBR and d max were statistically analysed as imaging features. @*Results @#Among 94 patients , the differences in SUV max , MRFDG , TBRSUV max and TBRMRFDG were statistically significant in the hepatocellular carcinoma , cholangiocellular carcinoma and hepatic metastasis groups (SUV max : F = 48. 773 , P < 0. 001 ; MRFDG : F = 26. 334 , P < 0. 001 ; TBRSUV : F = 41. 314 , P < 0. 001 ; TBRMRFDG : F = 20. 821 , P < 0. 001) . The AUCs for the differential diagnosis of primary hepatocellular carcinoma and hepatic metastases for SUV max , MRFDG , TBRSUV max , and TBRMRFDG were 0. 836 , 0. 851 , 0. 827 , and 0. 847 , respectively. There was a positive correlation between SUV max , MRFDG , and the hepatic malignant lesions ′ There was a positive correlation between SUV max , MRFDG and the maximum diameter d max (SUV max : r = 0. 4 , P < 0. 05 ; MRFDG :r = 0. 2 , P < 0. 05) , and the difference was statistically significant. @*Conclusion @#18 F ⁃FDG PET/CT dynamic imaging has good differential diagnostic efficacy in different pathological types of liver malignant tumors. There is a positive correlation between SUV max , MRFDG and d max in different pathological types of liver malignant tumors.

The value of 18F-FDG PET-CT in predicting relapse of type 1 autoimmune pancreatitis / 中华胰腺病杂志

Objective:To investigate the predictive value of F-2-fluoro-2-deoxy-D-glucose ( 18F-FDG) PET-CT metabolic parameters for the recurrence of type 1 autoimmune pancreatitis (AIP). Methods:Eighty-six patients with type 1 AIP who met the International Consensus Diagnostic Criteria (ICDC) and underwent 18F-FDG PET-CT before interventional treatment at the PLA General Hospital between May 2009 and June 2021 were included and divided into recurrence group ( n=43) and no-recurrence group ( n=43) according to whether they recurred after treatment. The standard uptake value (SUV)≥2.5 fixed threshold was used to outline the pancreatic lesion volume of interest (VOI) in three dimensions, and the three-dimensional diameter of the lesion, maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), peak standardized uptake value (SUVpeak), metabolic tumor volume (MTV), total lesion glycolysis (TLG), target-to-bench ratio (TBR) and standardized uptake value ratio (SUVR) were measured to compare the clinical characteristics, biochemical indices and treatment of the two groups; univariate and multifactorial regression analysis were used to examine 18F-FDG PET/CT visual indices of pancreatic lesions and extra-pancreatic involved organs as well as metabolic parameters in the two groups. A recurrence prediction model was constructed and its predictive efficacy was assessed. Results:The proportion of patients receiving glucocorticoid maintenance therapy was significantly higher in the no-recurrence group than in the recurrence group (58% vs 23.3%), and the serum IgG4 levels before treatment were significantly higher in the recurrence group [(15 309±11 724) mg/L vs (8 816±7 169) mg/L]. The results of univariate analysis showed that the proportion of extra-pancreatic salivary gland involvement and VOI, SUVmax, SUVpeak, SUVR, TBR, MTV, and TLG were significantly higher in the recurrence group than in the no-recurrence group, and the differences were statistically significant (all P values <0.05); the results of multivariate analysis showed that VOI ( OR=1.012, 95% CI 1.001-1.023 ), SUV max ( OR=1.398, 95% CI 1.029-1.899), SUV peak ( OR=1.408, 95% CI1.002-1.978), SUVR ( OR=1.977, 95% CI1.036-3.771) and MTV ( OR=1.012, 95% CI1.000- 1.022) in the recurrence group were significantly higher than those in the no-recurrence group, and all differences were statistically significant (all P values <0.05). The prediction model was constructed by multifactorial binary logistic regression analysis of SUVR>2, MTV>36 cm 3, and IgG4>11 400 mg/L, which had an AUC of 0.800 (95% CI 0.704-0.897), sensitivity of 81.4% (95% CI 0.661-0.911), specificity of 74.4% (95% CI 0.585-0.860), and prediction accuracy of 77.9%. Conclusions:18F-FDG PET/CT metabolic parameters can be used as predictors of type 1 AIP recurrence; a multiparameter model constructed based on metabolic parameters SUVR, MTV and IgG4 has a good predictive efficacy for predicting type 1 AIP recurrence.

Evaluation of 18F-FDG PET/CT myocardial metabolism image quality / 中国医师杂志

Objective:To evaluate the value of 18F-fluorodeoxyglucose positron emission computed tomography ( 18F-FDG PET/CT) myocardial metabolic image quality by the ratio of the maximum standard uptake value (M/B) of left ventricular myocardium to cardiac blood pool. Methods:The clinical data of 145 non diabetes patients with coronary heart disease who were admitted to the First Affiliated Hospital of Xinjiang Medical University from January 2016 to August 2022 were retrospectively selected. All patients received intravenous injection of 18F-FDG for myocardial glucose metabolism imaging. According to the visual (qualitative) analysis, the image was divided into three categories: the best, the second best and the worst. Group A was the best image quality group, while Group B was the second best and the worst image quality group. The left ventricular myocardium, cardiac blood pool and descending aorta were semi-quantitatively analyzed, and M/B was calculated. Results:All 145 patients underwent image fusion analysis. Image visual (qualitative) analysis showed that the myocardial metabolic image quality of 111 patients was evaluated as the best (111 patients in Group A), 19 patients as the second best, and 15 patients as the worst (34 patients in Group B). The SUVmax value of the descending aorta in the two groups was lower than that of the left ventricle, with statistically significant difference (all P<0.05). The M/B value of group A was higher than that of group B, with statistically significant difference ( P<0.05). Conclusions:For the evaluation of image quality and the reliability of image interpretation, M/B value may be a good evaluation index, which reduces the interference of image quality evaluation due to high 18F-FDG uptake in some heart blood pools (background), and improves the accuracy of evaluation of myocardial viability.

Value of dynamic 18F-FDG PET/CT semi-quantitative parameters in the diagnoses of non-small cell lung cancer subtypes and lymph node metastasis / 中华核医学与分子影像杂志

Objective:To explore the values of dynamic 18F-FDG PET/CT semi-quantitative parameters in the differentiation of histological subtypes of non-small cell lung cancer (NSCLC) and the diagnosis of lymph node metastasis. Methods:Twenty-three patients (10 males, 13 females, age (61.5±8.1) years) with NSCLC in Shengjing Hospital of China Medical University were prospectively enrolled between October 2020 and June 2021. All patients underwent 40 min of dynamic PET/CT scan and static scan at 60 min post-injection of 18F-FDG. SUV max, SUV mean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of primary lesions at different stages of PET/CT imaging were evaluated. SUV max of lymph nodes were also analyzed. The histopathological results were considered as the gold standard. Parameters of primary lesions and lymph nodes at different PET/CT imaging stages in different groups were compared by independent-sample t test or Mann-Whitney U test. The diagnostic efficiencies of those parameters were tested by ROC curve and compared by DeLong test. Results:A total of 24 lesions in 23 patients were pathologically confirmed as NSCLC, of which 11 were squamous cell carcinoma and 13 were adenocarcinoma. The SUV max (13.5±3.4 vs 9.6±5.1), SUV mean (8.1±2.2 vs 5.8±3.2) at the third stage of dynamic PET/CT (33-40 min) between squamous cell carcinoma and adenocarcinoma were both significantly different ( t values: 2.20, 2.10, P values: 0.039, 0.048). SUV max, TLG of static PET/CT between the 2 groups were also different ( t=2.22, P=0.037; z=-2.17, P=0.030). ROC curves of those parameters showed that AUCs were between 0.727 and 0.762. Fourteen patients underwent surgery and lymph node dissection. According to the pathological results, lymph nodes in 15 areas were metastatic, the rest in 70 areas were benign. There were significant differences in SUV max at the second stage of dynamic PET/CT (19-26 min) between metastatic and benign lymph nodes (4.0(2.8, 6.2) vs 2.3(1.8, 2.8); z=-4.31, P<0.001), as well as SUV max at the third stage of dynamic PET/CT and static PET/CT between the 2 groups ( z values: -4.59, -4.10, both P<0.001). ROC curves of those 3 parameters showed that the AUCs were 0.856, 0.879 and 0.838 respectively, with no significant differences ( z values: 0.78, 0.34, 1.27, P values: 0.434, 0.734, 0.205). The sensitivity, specificity, and accuracy of the SUV max of the third dynamic imaging stage were 13/15, 90.0%(63/70) and 89.4%(76/85), respectively. Conclusion:Dynamic 18F-FDG PET/CT semi-quantitative parameters have certain clinical significance in the identification of histological subtypes of NSCLC and the diagnosis of metastatic lymph nodes, especially the third stage dynamic imaging has a better diagnostic performance.

Imaging study of 18F-SDM-8 in rat temporal lobe epilepsy model / 中华核医学与分子影像杂志

Objective:To explore whether the specific synaptic vesicle glycoprotein 2A (SV2A) targeted imaging agent ( R)-4-(3-fluoro-5-(fluoro- 18F)phenyl)-1-((3-methylpyridin-4-yl)methyl)pyrrolidin-2-one ( 18F-SDM-8) can be used to detect epileptic foci. Methods:Twenty male Sprague-Dawley (SD) rats (8-9 weeks) were injected with 1.2 μl of kainic acid (16 rats in the epilepsy group) or saline (4 rats in the control group) into the right hippocampus. 18F-SDM-8 and 18F-FDG mircoPET/CT imaging were respectively performed at 1-2 d (acute phase), 6-7 d (incubation period) and 45-60 d (chronic phase) after the seizure. Asymmetric index (AI) was used to evaluate the epileptic foci identify ability of 18F-SDM-8. Paired t test, Mann-Whitney U test and Pearson correlation analysis were used to analyze data. Results:In the three periods of 18F-SDM-8 imaging, the differences of AI of hippocampus between the epilepsy group and control group were statistically significant ( z values: from -2.64 to 2.67, all P<0.05). Both imaging agents had asymmetric uptake in the epilepsy group (right was lower than left), and the decrease in the medial right temporal lobe was the most significant. The pathological staining results were consistent with the imaging results. In the chronic phase of the epilepsy group, the differences of 18F-SDM-8 SUV mean (right versus left) in each brain area of interest were statistically significant ( t value: from -33.40 to -5.60, all P<0.05). The asymmetric uptake of the two imaging agents in the hippocampus had a better correlation ( r=0.97, P=0.001), and the AI of 18F-SDM-8 ((34.2±8.4)%) in this area was 1.4 times higher than that of 18F-FDG ((24.6±4.7)%). Conclusions:18F-SDM-8 PET is a promising method to test the level of SV2A. It can reflect the changes of SV2A in the rat epilepsy model induced by intrahippocampal injection of kainic acid, and improve the sensitivity of molecular imaging for epileptic foci.

Clinical and 18F-FDG PET/CT imaging features of hilar tumor pulmonary infarction / 中华核医学与分子影像杂志

Objective:To investigate the clinical manifestations and 18F-FDG PET/CT imaging features of hilar tumor pulmonary infarction. Methods:From July 2016 to June 2021, 49 patients (40 males, 9 females; age 32-81 years) with hilar tumor pulmonary infarction who underwent PET/CT and enhanced CT in the second Hospital of Shandong University and Shandong Cancer Hospital and Institute, Shandong First Medical University were retrospectively enrolled. All patients were diagnosed by imaging follow-up or pathology. Clinical features and 18F-FDG PET/CT imaging features were analyzed. Results:A total of 108 infarcts were found in 49 patients by 18F-FDG PET/CT. Small cell carcinoma was the most common hilar tumor (67.35%, 33/49). The most common clinical manifestations of hilar tumor pulmonary infarction were cough (69.39%, 34/49) and hemoptysis (34.69%, 17/49). Pulmonary infarction was mainly multiple (69.39%, 34/49), and multiple lung lobes might be involved. The CT morphology of infarcts was wedge-shaped (46.30%, 50/108) or patchy (53.70%, 58/108), and the density was mainly bubble consolidation (61.11%, 66/108). There were 91 (84.26%, 91/108) infarcts showing FDG hypermetabolism, with the SUV max of 1.48-6.62, and the hypermetabolism mode was rim sign (36.11%, 39/108) or heterogeneous hypermetabolism (48.15%, 52/108). Nineteen patients (38.78%, 19/49) were complicated with pulmonary vein involvement, and 26 patients (53.06%, 26/49) had ipsilateral pleural effusion. Conclusions:Hilar tumor pulmonary infarction is characterized by cough. It is helpful for the diagnosis of hilar tumor pulmonary infarction in patients with hilar tumor when wedge-shaped, bubble consolidation, rim sign and heterogeneous hypermetabolism lesions are found in 18F-FDG PET/CT images.