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Objective:To investigate the correlation between the SUV index (SUV max of the lesion/SUV mean of the liver) in 18F-FDG PET/CT imaging and the invasiveness of early lung adenocarcinoma presenting as ground-glass nodule (GGN). Methods:From January 2012 to March 2020, 167 GGN patients (49 males, 118 females; age: (61.5±9.0) years) with early lung adenocarcinoma who underwent PET/CT imaging in Changzhou First People′s Hospital were retrospectively enrolled. The image parameters including the GGN number, location, type, edge, shape, abnormal bronchus sign, vacuole sign, pleural depression, vessel convergence sign, GGN diameter ( DGGN), solid component diameter ( Dsolid), consolidation to tumor ratio (CTR, Dsolid/ DGGN), CT values (CT value of ground-glass opacity (CT GGO), CT value of lung parenchyma (CT LP), ΔCT GGO-LP (CT GGO-CT LP)) and SUV index were analyzed. Single and multivariate logistic regressions were used to analyze the correlation between SUV index and infiltration. The generalized additive model was used for curve fitting, and the piece-wise regression model was used to further explain the nonlinearity. Results:In 189 GGNs, invasive adenocarcinoma accounted for 85.2% (161/189). Single logistic regression showed that the GGN number, type, shape, edge, abnormal bronchus sign, pleural depression, vessel convergence sign, DGGN, Dsolid, CTR, CT GGO, ΔCT GGO-LP and SUV index were related factors of infiltration (odds ratio ( OR) values: 0.396-224.083, P<0.001 or P<0.05). After fully adjusting for confounding factors, SUV index was significantly correlated with increased risk of invasion ( OR=2.162 (95% CI: 1.191-3.923), P=0.011). Curve fitting showed that the SUV index was non-linearly related to the risk of infiltration, and the risk of infiltration increased significantly only when the SUV index was greater than 0.43 ( OR=3.509 (95% CI: 1.429-8.620), P=0.006). The correlation between SUV index and infiltration had no interaction between age, vacuoles, pleural depression and CTR subgroups (all P>0.05). Conclusions:SUV index is an independent factor related to the invasiveness of early lung adenocarcinoma. The higher the SUV index, the greater the risk of invasion; but the two are not simply linearly correlated.
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Objective:To construct and verify of the predictive models for pathologic invasion of early lung adenocarcinoma with ground glass nodules (GGNs) based on 18F-FDG PET/CT. Methods:A retrospective analysis was conducted on 149 patients (44 males, 105 females; age (61.1±8.9) years) with pre-invasive lesions/minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) confirmed by pathology after surgery in the First People′s Hospital of Changzhou from October 2011 to October 2019. All patients underwent PET/CT for GGNs. GGNs were randomly divided into a modeling group and validation group with the proportion of 1∶1. Mann-Whitney U test or χ2 test was used to compare the qualitative morphological characteristics (shape, edge characteristics, etc.), quantitative parameters (consolidation-to-tumor ratio, attenuation value of the ground glass opacity (GGO) component on CT (CT GGO), etc.) and quantitative functional parameters (SUV max and SUV index(GGNs SUV max/liver SUV mean) of pre-invasive lesions/MIA and IAC. Logistic regression analysis was used to construct the models, and the ROC curve was used to verify the models′ robustness. Different AUCs were compared by Delong test. Results:A total of 170 GGNs were removed by surgery and confirmed pathologically. In the modeling group ( n=89), the proportion of mixed GGNs, irregular shape, edge characteristics, bronchiectasis/twist/truncation sign, GGNs maximum diameter and solid component maximum diameter, consolidation-to-tumor ratio, CT GGO, SUV max and SUV index in IAC group were significantly higher than those in pre-invasive/MIA group ( χ2 values: 5.00-23.40, z values: from -6.53 to -2.70, all P<0.05). Models 1-3 were constructed based on the qualitative parameters (GGNs type, edge characteristics), quantitative parameters (CT GGO, SUV index), combined qualitative and quantitative parameters (GGNs type, edge characteristics, SUV index) of PET/CT, respectively, and the AUCs of ROC were 0.896, 0.880 and 0.931 in the modeling group, respectively. And the AUC of model 2 was not decreased significantly in the validation group ( n=81; AUC=0.802; z=0.81, P=0.417). Conclusion:The model combined with morphological and functional quantitative parameters of 18F-FDG PET/CT can effectively predict the pathological invasion of early lung adenocarcinoma, and the constructed model is robust.
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Objective:To explore the relationship between the maximum standard uptake value (SUV max) based on 18F-fluorodeoxyglucose (FDG) PET-CT and the epidermal growth factor receptor (EGFR) mutation status of lung adenocarcinoma appearing as ground glass nodules (GGN). Methods:A total of 103 patients with lung adenocarcinoma from October 2011 to December 2020 in the Third Affiliated Hospital of Soochow University were retrospectively enrolled. All patients underwent 18F-FDG PET-CT and high-resolution CT, and underwent surgical resection and EGFR detecting within one month. The patients were divided into EGFR mutation group and wild group according to the EGFR test results. The GGN number, type, location, shape, lobulation sign, spicule sign, abnormal bronchial sign, vacuole sign, pleural indentation, diameter of GGNs (D GGN), diameter of solid component (D solid) and nodule ground-glass opacity component CT mean (CT GGO) were analyzed on CT images. The maximum standard uptake value (SUV max) of nodules was measured on PET-CT images. The t test, Mann-Whitney U test or χ 2 test were used to compare the differences of clinical data, pathological data, CT imaging parameters and SUV max between the two groups. Hierarchical binary logistic regression model was used to assess whether there was any association between SUV max and EGFR mutation status in different subgroups. Generalized additive model and smooth curve fitting were applied to solve nonlinear problems, and piecewise binary logistic regression model was used to explain nonlinearity. Results:A total of 103 patients with 106 nodules were finally included. There were 75 patients (78 nodules) in the EGFR mutation group and 28 patients (28 nodules) in the EGFR wild group. Adenocarcinomas with EGFR mutation showed significantly higher spiculated edge, pleural depression sign and invasive adenocarcinoma proportions than those in EGFR wild group ( P<0.05). There were no significant differences in other indicators between groups ( P>0.05). After adjusting for age and fasting blood glucose, gender and the number of GGNs significantly affected the relationship between SUV max and EGFR mutation ( P<0.05), which suggested that there was an interaction. After adjusting for confounding factors, there was a non-linear relationship between SUV max and EGFR mutation status in female subgroup (degree of freedom was 1.817, P=0.026). When SUV max<2.4, the risk of EGFR mutation increased significantly with the increase of SUV max (OR=43.621, 95%CI 4.686-406.042), P<0.001]. When SUV max>2.4, the risk of EGFR mutation increased insignificantly ( P=0.392). Conclusions:Lung adenocarcinoma appearing as GGN has a higher risk of EGFR mutation. The risk of EGFR mutation in female patients increases with increasing SUV max, but there is saturation effect.
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Objective:To investigate the predictive value of 18F-fluorodeoxyglucose (FDG) PET/CT metabolic parameters for occult lymph node metastasis (OLM) in non-small cell lung cancer (NSCLC). Methods:A total of 183 patients (72 males, 111 females; age (61.5±8.4) years) who underwent 18F-FDG PET/CT and preoperatively diagnosed with clinical N0 stage (cN0) in Third Affiliated Hospital of Soochow University from January 2013 to December 2018 were retrospectively enrolled. All patients underwent anatomical pulmonary resection with systematic lymph node dissections within 3 weeks after 18F-FDG PET/CT examinations. According to the presence or absence of lymph node metastasis, patients were divided into OLM positive (OLM+ ) group and OLM negative (OLM-) group. Parameters of primary lesions, such as the maximum diameter (D max), tumor sites, morphological features, maximum standardized uptake value (SUV max), mean standardized uptake value (SUV mean), metabolic total volume (MTV), total lesion glycolysis (TLG), tumor SUV max to liver SUV mean (TLR max), tumor TLG to liver SUV mean (TLR TLG) were analyzed. Mann-Whitney U test and χ2 test were used to compare the parameters between groups. Multivariable logistic regression was used to analyze the independent risk factors for OLM. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of different parameters. Results:Among 183 patients, 25 (13.7%, 25/183) of them were diagnosed as OLM. In OLM+ group, 46 lymph nodes were pathologically positive for metastasis, including 15 N1 disease and 31 N2 disease. D max (2.9(2.3, 3.7) vs 2.3(1.7, 2.8) cm), lobulation ((76.0%(19/25) vs 37.3%(59/158)), SUV max (11.1(7.9, 17.7) vs 4.7(2.3, 9.2)), TLG (41.5(10.2, 91.1) vs 15.6(6.5, 23.8) ml), TLR max (4.7(3.5, 7.6) vs 2.1(0.9, 4.0)) and TLR TLG (18.1(5.0, 44.3) vs 6.1(3.0, 11.4) ml) of the primary lesions in OLM+ group were significantly higher than those in OLM-group ( z values: from -4.709 to -3.247, χ2=13.190, all P<0.05). Multivariable logistic regression analysis showed that TLR max (odds ratio ( OR)=15.145, 95% CI: 3.381-67.830, P<0.001) and D max ( OR=3.220, 95% CI: 1.192-8.701, P=0.021) were independent risk factors for OLM. TLR max yielded the highest area under curve (AUC; AUC=0.794) with the threshold of 3.12, and the sensitivity, specificity, accuracy, positive predictive value and negative predictive value for predicting OLM were 92.0%(23/25), 63.3%(100/158), 67.2%(123/183), 28.4%(23/81) and 98.0%(100/102), respectively. Conclusions:TLR max of tumor is the independent risk factor for OLM in NSCLC patients. TLR max can sensitively predict OLM preoperatively in patients with NSCLC.
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Objective:To evaluate the diagnostic value of circulating microRNA-1 (miR-1) in early coronary artery plaque rupture in patients with stable coronary artery disease (SCAD).Methods:A prospective cohort study was conducted. Sixty-seven patients with SCAD admitted to the department of cardiology of the Third Affiliated Hospital of Soochow University from January to June in 2019 were enrolled. All patients had completed coronary angiography (CAG), percutaneous coronary intervention (PCI) single stent implantation or only CAG was performed according to the CAG results. Blood samples were collected before (0 hour) and 3 hours after the procedure. The expression of plasma miR-1 was detected by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR), and electrocardiogram was used to detect cardiac troponin I (cTnI) levels. The difference of miR-1 and cTnI levels in PCI or CAG patients before and after procedure were compared, and the value for early diagnosis of coronary artery plaque rupture in SCAD patients was evaluated. The diagnostic efficacy was evaluated by the receiver operating characteristic curve (ROC curve).Results:There were 38 CAG patients and 29 PCI patients. There were no significant differences in gender, age, previous history (without hypertension history) and baseline data of cardiac function between the two groups. The expression of miR-1 after PCI was significantly higher than that before PCI [2 -ΔΔCt: 2.11 (1.56, 2.73) vs. 1.26 (1.07, 1.92), P < 0.01], and there was no significant difference in cTnI level before and after PCI [μg/L: 0.00 (0.00, 0.02) vs. 0.00 (0.00, 0.02), P > 0.05]. There were no significant differences in miR-1 and cTnI levels before and after procedure in the CAG group [miR-1 (2 -ΔΔCt): 1.09 (1.00, 1.40) vs. 1.21 (1.00, 1.71), cTnI (μg/L): 0.00 (0.00, 0.02) vs. 0.00 (0.00, 0.02), both P > 0.05]. ROC curve analysis showed that the area under ROC curve (AUC) and 95% confidence interval (95% CI) of miR-1 in the diagnosis of coronary plaque rupture were 0.794 (0.687-0.900), P < 0.01, the sensitivity was 82.8%, the specificity was 68.4%, and the optimal cut-off value was 1.51. The AUC and 95% CI of the difference of miR-1 before and after operation (ΔmiR-1) were 0.704 (0.567-0.842), P = 0.004, the sensitivity was 62.1%, the specificity was 84.2%, and the optimal cut-off value was 0.39. The efficancy of miR-1 and ΔmiR-1 after procedure to diagnose coronary plaque rupture in patients with SCAD was similar ( Z = 1.287, P = 0.198). However, baseline miR-1 might not predict whether patients with SCAD need PCI or not (AUC = 0.630, P > 0.05). Multivariate binary Logistic regression analysis showed that increased postoperative miR-1 expression was an independent risk factor for coronary plaque rupture in SCAD patients [odds ratios ( OR) = 2.887, 95% CI was 1.044-7.978, P = 0.041]. Conclusion:Circulating miR-1 might have the value for early diagnosis of coronary artery plaque rupture in SCAD patients.
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Objective:To explore the value of 18F-deoxyglucose (FDG) PET and high resolution CT (HRCT) combined prediction model in the identification of invasiveness of early lung adenocarcinoma with consolidation-to-tumor ratio (CTR)≤0.5. Methods:A retrospective analysis was performed on 91 patients with early lung adenocarcinoma with CTR≤0.5 who underwent PET/CT and HRCT before surgery in the Third Affiliated Hospital of Soochow University from October 2011 to October 2019, including 110 ground-glass nodules (GGNs). According to the pathological subtypes, they were divided into preinvasive-minimally invasive adenocarcinoma (MIA) group ( n=22) and invasive adenocarcinoma (IAC) group ( n=88). The image feature parameters of GGNs of the two groups were compared, and the HRCT model and PET-HRCT combined model were constructed using Logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was used to compare the diagnostic efficacy of different models. The Bootstrap resampling (times = 500) method was used for internal verification of the model, and we also performed interaction and hierarchical analysis on the model. Results:The proportions of mixed GGN, irregular shape, lobulation sign, dilated/distorted/cutoff bronchial sign, pleural indentation and vascular convergence in IAC group were significantly higher than those in preinvasive-MIA group (all P<0.05). Nodule diameter, solid component diameter, solid component ratio, CT value of ground glass attenuation component (CT GGO), and SUVindex of the IAC group were larger than those of the preinvasive-MIA group, and the differences were statistically significant ( P<0.001). Among the quantitative parameters of HRCT, CT GGO had the best diagnostic efficacy (AUC=0.775), with a sensitivity of 0.580 and a specificity of 0.909. The diagnostic efficacy of HRCT model and PET-HRCT combined model were better than CT GGO (AUC: 0.907 vs. 0.775, 0.931 vs. 0.775; P=0.027, 0.002, respectively), but the diagnostic efficacy of the former two was not statistically different ( P=0.210).When the specificity was 0.909, the sensitivity of the HRCT model and the PET-HRCT model (0.784 and 0.875, respectively) were significantly higher than that of the CT GGO (0.580), and the combined PET-HRCT model had a more significant increase in sensitivity. The PET-HRCT combined model showed no significant interaction between different nodule types, between groups with or without pleural indentation, and among nodule diameter subgroups (all P>0.05). Conclusion:PET-HRCT combined model has a good predictive value for the invasiveness of early lung adenocarcinoma with CTR≤0.5, and it can be used for GGN risk stratification to guide clinical decision-making.
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Diabetes, obesity, and metabolic diseases are globally prevalent, and induction and increase of endogenous energy consumption, especially activation of brown adipose tissue (BAT), is a new therapeutic target. Non-invasive imaging techniques, including radionuclide imaging, MRI, ultrasound imaging, and optical imaging, have attracted wide attention in BAT monitoring and have good application prospects. This article reviews the progress and application of these imaging techniques in BAT monitoring.
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Objective@#To analyze the risk factors of delirium in intensive care unit (ICU) patients, and to investigate the predictive value of C-reactive protein (CRP), procalcitonin (PCT), lactic acid (Lac) and neuron-specific enolase (NSE) in the diagnosis of ICU delirium.@*Methods@#The patients admitted to central ICU and respiratory medicine ICU of Changzhou First People's Hospital from August 2016 to November 2017 were enrolled. The patients were divided into two groups according to whether delirium occurred within 7 days or not, which was evaluated by using the confusion assessment method for ICU (CAM-ICU). The gender, age and blood CRP, PCT, Lac, NSE levels were compared between the two groups. Multivariate Logistic regression model was used to analyze the risk factors of ICU delirium. Receiver operating characteristic curve (ROC) was drawn to assess the predictive value of CRP, PCT, Lac and NSE in the occurrence of ICU delirium.@*Results@#133 patients were enrolled. Delirium occurred in 67 patients, and did not occurred in 66 patients, with a prevalence rate of 50.4%. There was no significant difference in gender or age between the two groups. Compared with non-delirium group, blood CRP, PCT and Lac levels in delirium group were significantly increased [CRP (mg/L): 110.75±77.31 vs. 51.32±36.51, PCT (μg/L): 3.95 (1.01, 23.90) vs. 0.09 (0.06, 0.36), Lac (mmol/L): 2.40 (1.70, 4.30) vs. 1.20 (0.90, 2.00), all P < 0.01], but no significant difference was found in NSE [μg/L: 12.59 (9.61, 17.69) vs. 13.39 (10.14, 19.05), P > 0.05].② It was shown by multivariate Logistic regression analysis that blood PCT and Lac were risk factors of ICU delirium [PCT: odds ratio (OR) = 1.185, 95% confidence interval (95%CI) = 1.006-1.396, P = 0.042; Lac: OR = 1.398, 95%CI = 1.011-1.934, P = 0.043].③ROC curve analysis showed that blood CRP, PCT and Lac had certain predictive value for ICU delirium, and the area under the ROC curve (AUC) of PCT was the highest (0.840 vs. 0.694 and 0.751). When the cut-off value of PCT ≥ 0.55 μg/L, the sensitivity was 72.7%, the specificity was 86.2%, positive predictive value was 84.48%, and negative predictive value was 75.68%. Blood NSE had no predictive value for ICU delirium (AUC = 0.446, P = 0.290).@*Conclusions@#Blood PCT and Lac are the risk factors of ICU delirium. PCT has predictive value for ICU delirium.
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Objective To compare changes in indexes and analyze their values in prognosis of severe burn patients with sepsis.Methods A retrospective analysis was conducted. The patients with severe burn sepsis admitted to the Third Affiliated Hospital of Soochow University from August 2014 to December 2016 were enrolled. The blood culture was positive in the clinical diagnosis of sepsis. According to the prognosis, the patients were divided into death group and survival group. Their general information, vital signs, blood routine examination, serum sodium (Na+), serum glucose (Glu), C-reactive protein (CRP) and arterial partial pressure of carbon dioxide (PaCO2) at the time of admission and diagnosis of sepsis as well as the level of serum procalcitonin (PCT) at admission, diagnosis of sepsis and 1-8 days of post diagnosis were also compared. Receiver operating characteristic curve (ROC) was used to analyze the prognostic value of each index, and multivariate Cox regression analysis was used to analyze the influence of each index on the survival time, and the survival curve of Kaplan-Meier was analyzed for dead patients.Results There were 25 cases of severe burn patients with sepsis, which were admitted to hospital within 12 hours after injury; the time of diagnosis of burn sepsis was (14±6) days; 8 cases of survival; 17 cases died, the mortality rate was 68.0%, the time from diagnosis of sepsis to death was (28±14) days. The age of the death group was significantly higher than that of the survival group (years: 41±12 vs. 29±9,t = 2.598,P = 0.016), but there was no significant difference in the gender, total burn area,Ⅲ degree area, and the time of diagnosis of sepsis between the two groups. The platelet count (PLT) at the diagnosis of sepsis in death group was significantly lower than that of the survival group (×109/L: 69±43 vs. 180±108,t = -2.773, P = 0.023), and the PCT at 1-8 days of post-diagnosis in the death group was significantly higher than that of survival group [μg/L: 4.4 (2.2, 9.0) vs. 1.6 (0.7, 2.3),Z = -2.521,P = 0.012], but there was no significant difference in body temperature, heart rate, white blood cell count (WBC), percentage of neutrophils (Neu), Na+, Glu, CRP, PCT, PaCO2 at the time of admission and diagnosis of sepsis and PLT at the time of admission between the two groups. ROC curve analysis showed that the area under ROC curve (AUC) of age, PLT at the time of diagnosis and PCT at 1-8 days of post-diagnosis of sepsis was 0.808, 0.779, 0.825, respectively, for predicting the prognosis of patients with severe burn sepsis (allP < 0.05). At the cut-off age of 32, the sensitivity was 73.3% and the specificity was 75.0%. As the cut-off of PLT was 138×109/L at the time of diagnosis, the sensitivity was 92.3% and the specificity was 75.0%. As the cut-off of PCT was 2.39μg/L at 1-8 days of post-diagnosis of sepsis, the sensitivity was 73.3% and the specificity was 87.5%. Multivariate Cox regression analysis showed that age and PLT at the time of diagnosis were the favorable factors for the survival time of patients with severe burn sepsis (β value were -1.834, -0.029, respectively, bothP < 0.05). Kaplan-Meier survival analysis for patients in the death group showed that the median survival time of patients ≥32 years old was longer than that of patients < 32 years old (days: 32 vs. 9); 18-day cumulative survival rate was significantly higher than that of patients < 32 years old [83.3% (10/12) vs. 25.0% (1/4),χ2 = 9.705,P = 0.003].Conclusion Age, PLT at diagnosis of sepsis and PCT at 1-8 days after diagnosis of sepsis could be used as prognostic indexes for severe burn patients with sepsis.
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Objective To investigate the characteristics of 18F-FDG PET/CT imaging in Takayasu arteritis (TA) and its clinical value.Methods Five male patients with TA in active phase (age range:65-82 years;mean age:(72.8±6.6) years) from November 2011 to August 2014 were retrospectively analyzed.All patients underwent 18F-FDG PET/CT imaging,and one of them who was in stable phase after one year's treatment underwent follow-up PET/CT imaging.The characteristics of the abnormal 18F-FDG uptake and SUVmax of lesions were analyzed.Another 5 age-and gender-matched patients with slightly elevated tumor markers and normal results of 18F-FDG PET/CT imaging in the same period were selected as the control group.Arteries were divided into 18 segments,including the ascending aorta,the aortic arch,the descending aorta,the abdominal aorta,the brachiocephalic trunk,the left/right common carotid,the left/right subclavian,the left/right brachial,the superior mesenteric,the left/right common iliac,the left/right renal,and the left/right femoral,and their SUVmax were measured respectively.Paired t test was used to analyze the difference of SUVmax between TA group and the control group.Results (1) 18 F-FDG PET/CT imaging displayed diffused increase of radioactivity in the wall of aorta and its major branches in TA group,and CT showed multiple irregular thickening,punctate and banding calcification in arterial walls of those patients.The ascending aorta,the aortic arch,the descending aorta,the abdominal aorta,the brachiocephalic trunk,the left/right subclavian,the left/right common carotid,and the left/right common iliac artery were all involved in 5 patients;the left/right brachial and the left/right femoral artery were involved in 4 patients and the superior mesenteric artery was involved in 2 cases.The SUVmax range was 1.4-7.6,the highest SUVmax was in the left subclavian artery (n=2),the right subclavian artery (n=1) and the abdominal aorta artery (n=2).(2)The SUVmax of TA group and the control group were 3.96±1.35 and 2.13±0.53,respectively(t=10.40,P＜0.001).(3) As to the TA patient in stable phase after treatment,the FDG uptake of the wall of aorta and its major branches decreased obviously compared with that before treatment.The SUVmax of left subclavian artery decreased from 6.8 to 3.2.Conclusions 18F-FDG PET/CT is helpful in diagnosis of TA.It could accurately display the range of involved arteries,reflect the activity of the lesion and evaluate the therapeutic response.
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PurposeCurrent conventional imaging methods X-ray, CT, MRI and ultrasound for rheumatic diseases are mostly local site imaging, rather than systemic display, thus is difficult to show the whole picture of the diseases, this study aims to explore the18F-FDG PET/CT findings of rheumatic diseases and its preliminary clinical value. Materials and Methods18F-FDG PET/CT imaging findings and clinical data of 18 patients with rheumatic diseases confirmed by clinical diagnosis were retrospectively analyzed, and 18F-FDG uptake of lesions was observed.Results Among all the 18 patients with rheumatic diseases: four cases were with rheumatoid arthritis (RA), 5 cases with takayasu arteritis (TA), 2 cases with adult onset Still’s disease (AOSD), 1 case with polymyalgia rheumatica (PMR) and 6 cases with ankylosing spondylitis (AS). Findings of PET/CT: RA showed increased FDG uptake in multiple bigger joints such as shoulder joint, elbow, hip, wrist joint, and part palm finger joints, with no bone abnormalities in CT; TA displayed as diffusely increased uptake of FDG the aorta and its major branches vascular wall while CT showed multiple arterial wall irregular thickening with dot or strip calcification, and in one case, the vascular wall FDG uptake decreased obviously after one year treatment, the SUVmax of left clavicle dropped from 6.8 to 3.2; AOSD showed diffusely increased FDG uptake in spleen and bone marrow, while CT had no obvious spleen and bone abnormalities; PMR showed increased uptake of FDG in the atlantoaxial joint, shoulder joint, sternoclavicular joint, hip joint, pubic symphysis, ischial tuberosity and lesions around lumbar spinous process; only 1 case of 6 AS patients showed left acetabular articular surface hyperplasia and sclerosis with increased FDG uptake, while CT showed spinal multiple vertebral bone hyperplasia and sclerosis as bamboo change in all of 6 AS cases, with normal FDG metabolism. Conclusion18F-FDG PET/CT is helpful for the diagnosis of rheumatic diseases, because it can be used to display the lesion extent, reflect its activity, and also to evaluate the effect of the treatments.
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PurposeSmart neuro attenuation correlation (SNAC) is a new method of calculated attention correction. This paper aims to evaluate the impact of SNAC on the quality and standardized uptake value of brain imaging with PET/CT.Materials and Methods Fifty-eight patients who underwent systematic scan with18F-FDG PET/CT were analyzed retrospectively. CT attenuation correlation (CTAC) and SNAC brain PET images were reconstructed respectively. All images were analyzed by visual assessment and Scenium software and the results of the two methods were compared with regard to image contrast, homogeneity and mean SUV at different cerebral regions. Moreover, the correlation of the mean SUV of the two methods was further analyzed.Results There was no significant visual difference of contrast and uniformity between SNAC and CTAC. The Scenium analysis shows that the contrast of SNAC images were slightly higher than that of CTAC, but the difference were not statistically significant (4.19±1.11vs. 4.08±1.03,t=0.764,P>0.05). The uniformity of SNAC images were slightly lower than that of CTAC (1.00vs. 0.83). The mean SUV at various brain regions measured by SNAC was greater than that by CTAC, but both were significantly correlated (r=0.978,P<0.01), and the linear regression analysis also demonstrated that the results were consistent (R2=0.959). Compared with that measured by CTAC, the average percentage difference of SUV measured by SNAC was 8.45±4.71, but it varied greatly at 10 brain regions (-8.56-27.93). The analysis of variance presented significant differences in the average percentage difference of SUV at different brain regions (F=119.084,P<0.01), while the average percentage difference at the outer slices was greater than that at the central slices. Conclusion No significant difference exists in image quality between SNAC and CTAC. Although the mean SUV at different brain regions measured by SNAC may increase by various degrees, it is significantly associated with the results measured by CTAC. Moreover, SNAC simplifies the process of examination and reduces radiation dose, which is beneficial to patients as a qualitative method.
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Purpose To analyze the PET image of normal human brain by using Scenium software, so as to ifnd out the change of cerebral glucose metabolism with different age and gender. Materials and Methods Brain PET imaging data of 493 healthy males and 273 healthy females were collected in the study. The subjects were divided into 6 groups according to age:21-30 years group,31-40 years group, 41-50 years group, 51-60 years group, 61-70 years group and 71-82 years group. Each group was further subdivided according to gender. The brain areas were automatically outlined by Scenium and the mean standard uptake value (SUV) of each brain area was calculated and compared among groups. Results Most cerebral glucose metabolism of males at different age was significantly different (F=2.580-5.316, P0.05); whilst difference in cerebral glucose metabolism of females at different age was not signiifcant (F=0.721-1.706, P>0.05). In male groups, cerebral glucose metabolism got peak at 31-40 years, and decreased signiifcantly at 51-60 years mainly involving areas like cinglulate gyrus, calcarine and surrounding cortex;and the groups after 61 years showed no signiifcant decrease. In female groups, cerebral glucose metabolism got peak at 31-40 years and showed no significant decrease along with age. Conclusion Cerebral glucose metabolism decreases unevenly after 40 years old. It drops significantly in males at 51-60 years whilst that in females is not obvious.