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Objective:To investigate the diagnostic and prognostic value of 68Ga-fibroblast activation protein inhibitor (FAPI) PET for hepatobiliary malignancies. Methods:From July 2020 to February 2023, 33 patients (23 males, 10 females; age (55.4±13.5) years) with suspected or confirmed liver or biliary tract malignancies who underwent 68Ga-FAPI PET in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively analyzed. PET images were evaluated by 3 experienced nuclear medicine physicians, and the results of biopsy or postoperative pathology, clinical and imaging follow-up were used as the gold standard. One-way analysis of variance and least significant difference t test were used to compare the differences among groups. Survival analysis was performed using Kaplan-Meier curves and the log-rank test. Results:Of 33 patients, 14 performed PET for initial diagnosis and staging, and 19 for restaging. There were 14 patients with hepatocellular carcinoma (HCC), 13 patients with cholangiocarcinoma (CCA), and 6 patients with gallbladder carcinoma (GBC). The primary tumor of HCC, CCA and GBC all showed significant 68Ga-FAPI uptake, with no statistically significant difference in SUV max among groups ( F=1.58, P=0.250). The sensitivities of 68Ga-FAPI PET for initial diagnosis and restaging of hepatobiliary malignancies were 14/14 and 15/15, respectively. Compared with conventional imaging, 68Ga-FAPI PET changed the diagnosis and staging in 29.2%(7/24) patients. The treatment strategy was changed in 30.3%(10/33) patients with malignant tumors due to 68Ga-FAPI PET findings. Follow-up showed 22 cases survived and 11 cases died, with the overall survival of 355.56(80.00, 516.97) d, and 1- and 2-year survival rates were 68.2% and 57.9%, respectively. Semi-quantitative 68Ga-FAPI PET parameters such as SUV max, target-liver ratio (TLR), and target-blood ratio (TBR) had no significant prognostic value, but the prognosis of the group without distant metastases diagnosed by 68Ga-FAPI PET was significantly better than that of the group with distant metastasis ( P=0.032). Conclusion:68Ga-FAPI PET has high sensitivity for the diagnosis of hepatobiliary malignancies, which can help guide treatment decisions and prognosis evaluation.
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Objective:To explore the impact of different segmentation methods on differential diagnostic efficiency of 18F-FDG PET/MR radiomics to distinguish Parkinson′s disease (PD) from multiple system atrophy (MSA). Methods:From December 2017 to June 2019, 90 patients (60 with PD and 30 with MSA; 37 males, 53 females; age (55.8±9.5) years) who underwent 18F-FDG PET/MR in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively collected. Patients were randomized to training set and validation set in a ratio of 7∶3. The bilateral putamina and caudate nuclei, as the ROIs, were segmented by automatic segmentation of brain regions based on anatomical automatic labeling (AAL) template and manual segmentation using ITK-SNAP software. A total of 1 172 radiomics features were extracted from T 1 weighted imaging (WI) and 18F-FDG PET images. The minimal redundancy maximal relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) algorithm were used for features selection and radiomics signatures (Radscore) construction, with 10-fold cross-validation for preventing overfitting. The diagnostic performance of the models was assessed by ROC curve analysis, and the differences between models were calculated by Delong test. Results:There were 63 cases in training set (42 PD, 21 MSA) and 27 cases in validation set (18 PD, 9 MSA). The Radscore values were significantly different between the PD group and the MSA group in all training set and validation set of radiomics models ( 18F-FDG_Radscore and T 1WI_Radscore) based on automatic or manual segmentation methods ( z values: from -5.15 to -2.83, all P<0.05). ROC curve analysis showed that AUCs of 18F-FDG_Radscore and T 1WI_Radscore based on automatic segmentation in training and validation sets were 0.848, 0.840 and 0.892, 0.877, while AUCs were 0.900, 0.883 and 0.895, 0.870 based on manual segmentation. There were no significant differences in training and validation sets between Radiomics models based on different segmentation methods ( z values: 0.04-0.77, all P>0.05). Conclusions:The 18F-FDG PET/MR radiomics models based on different segmentation methods achieve promising diagnostic efficacy for distinguishing PD from MSA. The radiomics analysis based on automatic segmentation shows greater potential and practical value in the differential diagnosis of PD and MSA in view of the advantages including time-saving, labor-saving, and high repeatability.
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Objective:To explore the diagnostic value of 68Ga-fibroblast activation protein inhibitor (FAPI) PET for the restaging of patients with colorectal cancer and its impact on treatment strategy. Methods:Patients with colorectal cancer who underwent 68Ga-FAPI PET imaging in the PET Center of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from June 2020 to June 2021 were retrospectively analyzed. PET images were evaluated by 3 experienced imaging physicians. Biopsy or postoperative pathology, clinical and imaging follow-up results were as the gold standard. The diagnostic value of PET was compared with conventional imaging (CT/MR), and the impact of 68Ga-FAPI PET on guiding treatment was evaluated. χ2 test and Fisher exact test were used to compare the differences between groups. Results:A total of 33 patients were included (17 males, 16 females, age (52.8±12.3) years), of which 24 were finally diagnosed as recurrence/metastases/progression. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of 68Ga-FAPI PET in detecting recurrence/metastases/progression of colorectal cancer were 93.9%(31/33), 100%(24/24), 7/9, 92.3%(24/26) and 7/7, respectively. Its accuracy, sensitivity and negative predictive value were significantly higher than those of conventional imaging (64.5%(20/31), 56.5%(13/23) and 7/17; χ2 values: 8.549 and 10.786, all P<0.05). Compared with the clinical or pathological stage before examination, 68Ga-FAPI PET led upstaging to stage Ⅳ in 12 patients (50.0%, 12/24). Of the 31 patients who were correctly diagnosed by 68Ga-FAPI PET, the treatment regimen of 22 patients (71.0%) was changed because of 68Ga-FAPI PET imaging. Conclusion:68Ga-FAPI PET has good diagnostic performance in the restaging of colorectal cancer, which is helpful to further guide clinical treatment strategy.
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At the end of December 2019, acute respiratory infectious diseases caused by a new type of coronavirus were prevalent in Wuhan and other cities of China. Different from radiology examinations, the protocols of nuclear medical imaging examinations are complicated, in which more workplaces and staff are needed, resulting more complex management of patients and higher protection requirements. Combined with the characteristics of SPECT and PET imaging procedures, this paper puts forward some suggestions on the protective process of imaging examinations for patients with confirmed or suspected noval coronavirus infec- tion. The main purpose is to protect medical staff from virus infection, effectively reduce the risk of virus transmission during the examination process, and ensure the medical quality and safety.
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At the end of December 2019, acute respiratory infectious diseases caused by a new type of coronavirus were prevalent in Wuhan and other cities of China. Different from radiology examinations, the protocols of nuclear medical imaging examinations are complicated, in which more workplaces and staff are needed, resulting more complex management of patients and higher protection requirements. Combined with the characteristics of SPECT and PET imaging procedures, this paper puts forward some suggestions on the protective process of imaging examinations for patients with confirmed or suspected novel coronavirus infection. The main purpose is to protect medical staff from virus infection, effectively reduce the risk of virus transmission during the examination process, and ensure the medical quality and safety.
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Objective:To explore the feasibility of statistical parametric mapping (SPM) aided semi-quantitative analysis in 11C-Pittsburgh compound B (PIB) β-amyloid (Aβ) PET imaging acquired by hybrid PET/MR, and evaluate its possibility in assisting the diagnosis or differential diagnosis for cognitive impairment. Methods:From January 2018 to September 2019, 13 Alzheimer′s disease (AD) patients (4 males, 9 females; age (59.2±5.8) years) and 10 vascular cognitive disorders (VCD) patients (9 males, 1 female; age (59.5±11.5) years) who underwent 11C-PIB PET/MR in PET center of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively analyzed. The standardized uptake value ratio (SUVR) of eight key brain regions (cerebral white matter, striatum, thalamus, posterior cingulate gyrus, frontal cortex, posterior parietal cortex, lateral temporal cortex and occipital cortex) to cerebellum cortex were obtained by manual delineation and SPM-aided semi-automatic segmentation with the help of synchronous three-dimensional T 1 weighted imaging (3D T 1WI). Pearson correlation analysis was carried out on the SUVR obtained by the two methods. Independent-sample t test and paired t test were used to analyze the data. Results:There was no significant difference between AD group and VCD group in age and Mini-Mental State Examination (MMSE) score (19.7±4.7 vs 21.7±3.8; t values: 0.095 and 1.098, both P>0.05). Except thalamus( r=0.179, P=0.413), there were good correlations between SUVR obtained by segmentation and delineation in the other 7 key regions ( r values: 0.678-0.893, all P<0.05). The SUVR of 8 key regions obtained by the two methods in AD group was significantly higher than that in VCD group (1.519-2.055 vs 1.105-1.618; t values: 2.799-11.582, all P<0.01). The SUVR of striatum (1.942±0.205), posterior cingulate gyrus (1.915±0.249), frontal lobe (1.983±0.264), parietal lobe (2.008±0.296) and temporal cortex (1.931±0.254) in AD group was significantly higher than that of cerebral white matter (1.746±0.192; t values: 3.793-6.992, all P<0.01). But in VCD group, there was no region with the SUVR higher than that of cerebral white matter. Conclusions:Hybrid PET/MR can acquire the PET and MRI images synchronously, which can realize the accurate brain segmentation and obtain the semi-quantitative data of key brain regions aided by SPM. The method can analyze the characteristics and differences of amyloid imaging in AD and VCD, which is expected to provide an accurate imaging analysis method for the diagnosis and differential diagnosis of cognitive disorders.
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The integrated PET/MR overcomes the problem of interferences between PET and the strong magnetic field of MRI, realizing the simultaneous acquisition of two modalities, which is a milestone in the field of medical imaging. The use of PET/MR requires the radiopharmaceutical as well as avoids interferences to the homogeneity of main magnetic field and stability of radio-frequency field from surrounding environment. Therefore, the site selection and layout design about integrated PET/MR are more complicated than the single mode system, and the results of installation and debugging should satisfy two imaging modalities (imaging quality and quantitative accuracy). In this paper, the room construction, installation and debugging of integrated PET/MR are discussed, which can supply a reference about key issues in the construction of similar projects.
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At the end of December 2019,acute respiratory infectious diseases caused by a new type of coronavirus were prevalent in Wuhan and other cities of China.Different from radiology examinations,the protocols of nuclear medical imaging examinations are complicated,in which more workplaces and staff are needed,resulting more complex management of patients and higher protection requirements.Combined with the characteristics of SPECT and PET imaging procedures,this paper puts forward some suggestions on the protective process of imaging examinations for patients with confirmed or suspected novel coronavirus infection.The main purpose is to protect medical staff from virus infection,effectively reduce the risk of virus transmission during the examination process,and ensure the medical quality and safety.
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Objective@#To discuss the correlation between 18F-fluorodeoxyglucose (FDG) imaging and arterial spin labeling perfusion weighted imaging (ASL-PWI) using synchronous PET/MR, and explore the feasibility of 18F-FDG PET and ASL for differential diagnosis in Parkinsonism (PS).@*Methods@#A retrospective analysis was performed in 24 patients with Parkinson′s disease (PD), 10 patients with multiple system atrophy (MSA) and 6 patients with progressive supranuclear palsy (PSP) who all underwent 18F-FDG PET/MR imaging from October 2017 to December 2018 (15 males, 25 females, age: 34-77 years). Synchronously acquired data, including MRI T1, 18F-FDG PET and three dimensional (3D) ASL-PWI were extracted. T1 structure image was used to register with standard brain template, and the personalized brain template of each patient was obtained. Then, the templates were matched to the corresponding PET and ASL-PWI images, and the mean standardized uptake value (SUVmean) and mean cerebral blood flow (CBFmean) of each brain region could be extracted. Pearson correlation analysis was used to evaluate the correlation between SUVmean and CBFmean of the whole brain and the regions of interest (ROI; caudate nucleus, putamen, midbrain, pons and cerebellum). One-way analysis of variance and least significant difference t test were used to evaluate the characteristics of SUVmean and CBFmean in different diagnostic groups. The diagnostic values of SUVmean and CBFmean in different ROI were evaluated with receiver operating characteristic (ROC) curve analysis.@*Results@#A total of 2 800 pairs of SUVmean and CBFmean were obtained from 40 cases in 3 groups. The overall correlation between them was good (r=0.468, P<0.01). There were also significant correlations between SUVmean and CBFmean in caudate nucleus, putamen, pons and cerebellum (r values: 0.346-0.492, all P<0.05). The CBFmean of cerebellum in MSA group was significantly lower than that in PD group ((36.92±11.35) vs (47.92±10.75) ml·100 g-1·min-1; F=4.817, t=2.675, P<0.05). Compared to the PSP group, CBFmean in caudate nucleus was higher in PD group ((30.02±3.51) vs (40.21±8.13) ml·100 g-1·min-1; F=5.393, t=2.969, P<0.05). The similar results were obtained for SUVmean. To differentiate PD with MSA, CBFmean of cerebellum possessed the highest diagnostic efficiency, with the area under ROC curve (AUC), sensitivity and specificity reaching 0.792, 83.3% and 70.0% respectively. To differentiate PSP with PD or MSA, CBFmean in caudate nucleus had the highest diagnostic efficiency, and the AUC were 0.903 and 0.933 respectively.@*Conclusions@#In patients with PD, MSA and PSP, the level of 18F-FDG glucose metabolism is in good agreement with the ASL cerebral blood flow perfusion obtained by synchronous PET/MR. The distribution characteristics of specific ROI in both PET and MR imaging can be helpful to the differential diagnosis of PS.
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Objective To discuss the correlation between 18 F-fluorodeoxyglucose (FDG) imaging and arterial spin labeling perfusion weighted imaging (ASL-PWI) using synchronous PET/MR,and explore the feasibility of 18F-FDG PET and ASL for differential diagnosis in Parkinsonism (PS).Methods A retrospective analysis was performed in 24 patients with Parkinson's disease (PD),10 patients with multiple system atrophy (MSA) and 6 patients with progressive supranuclear palsy (PSP) who all underwent 18 F-FDG PET/MR imaging from October 2017 to December 2018 (15 males,25 females,age:34-77 years).Synchronously acquired data,including MRI T1,18F-FDG PET and three dimensional (3D) ASL-PWI were extracted.T1 structure image was used to register with standard brain template,and the personalized brain template of each patient was obtained.Then,the templates were matched to the corresponding PET and ASL-PWI images,and the mean standardized uptake value (SUVmean) and mean cerebral blood flow (CBFmean) of each brain region could be extracted.Pearson correlation analysis was used to evaluate the correlation between SUVmean and CBF of the whole brain and the regions of interest (ROI;caudate nucleus,putamen,midbrain,pons and cerebellum).One-way analysis of variance and least significant difference t test were used to evaluate the characteristics of SUVmean and CBFmean in different diagnostic groups.The diagnostic values of SUVmean and CBF in different ROI were evaluated with receiver operating characteristic (ROC) curve analysis.Results A total of 2 800 pairs of SUVmean and CBFmean were obtained from 40 cases in 3 groups.The overall correlation between them was good (r=0.468,P＜0.01).There were also significantcorrelations between SUVmean and CBFmean in caudate nucleus,putamen,pons and cerebellum (r values:0.346-0.492,all P＜0.05).The CBFmean of cerebellum in MSA group was significantly lower than that in PD group ((36.92±11.35) vs (47.92±10.75) ml · 100 g-1 · min-1;F=4.817,t=2.675,P＜0.05).Compared to the PSP group,CBF in caudate nucleus was higher in P D group ((30.02± 3.51) vs (40.21±8.13) ml · 100 g-1 · min-1;F=5.393,t=2.969,P＜0.05).The similar results were obtained for SUVmean.To differentiate PD with MSA,CBFmean of cerebellum possessed the highest diagnostic efficiency,with the area under ROC curve (AUC),sensitivity and specificity reaching 0.792,83.3％ and 70.0％ respectively.To differentiate PSP with PD or MSA,CBF in caudate nucleus had the highest diagnostic efficiency,and the AUC were 0.903 and 0.933 respectively.Conclusions In patients with PD,MSA and PSP,the level of 18F-FDG glucose metabolism is in good agreement with the ASL cerebral blood flow perfusion obtained by synchronous PET/MR.The distribution characteristics of specific ROI in both PET and MR imaging can be helpful to the differential diagnosis of PS.
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HIFU is a new technology of noninvasive tumorectomy, which take use of thermal effects, mechanical effects and cavitation effects, etc. Currently, One of the difficulties in clinical application is how to determine energy dose of HIFU and resulted biological change. This paper expounds the factors such as sound intensity, irradiation duration, treatment depth, sound environment,etc. ,which affect energy input and therapeutic efficiency in HIFU treatment.