Objective To explore the characteristic of SPECT/CT imaging of osteolytic lesions with increased bone metabolism and its correlation with CT manifestation. Methods Twenty?one cancer patients with bone metastases underwent 99 Tcm?MDP SPECT/CT imaging ( 13 males, 8 females; age: ( 60. 52 ± 6?85) years) were retrospectively studied. The imaging characteristic of the lesion with high uptake of 99Tcm?MDP was observed and the correlation between the lesion/background ( L/B ) ratio and CT manifestation were analyzed. One?way analysis of variance, two?sample t test and linear correlation analysis were used. Results A total of 111 lesions were found in 21 patients by 99 Tcm?MDP whole?body bone scan, and 125 le?sions were found by SPECT/CT imaging, including 111 lesions with increased bone metabolism and abnor?mal CT manifestation and 14 osteolytic lesions with decreased bone metabolism. In 111 lesions with in?creased bone metabolism, there were 23(20.72%) osteolytic lesions, 54 (48.65%) osteoblastic lesions and 34 (30.63%) mixed lesions. The L/B ratio of osteolytic lesions with increased bone metabolism (11.82± 6?61) was lower than that of osteoblastic lesions (20.03±13.24) and that of mixed lesions (25.42±19.51;F=6.00, P<0?05) . The CT value of osteolytic lesions with increased bone metabolism was higher than that of osteolytic lesions with decreased bone metabolism :(167.53±79.21) HU vs (88.63±49.16) HU; t=3?345, P<0.05. The L/B ratio of lesions with increased bone metabolism was positively correlated to CT val?ue(r=0.404, P<0?05). Conclusions A part of lesions with increased bone metabolism on SPECT/CT im?ages are osteolytic lesions. The L/B ratio of them is positively correlated to CT value. SPECT/CT imaging can reduce missed diagnosis and misdiagnosis.

Objective To explore the significance of 18fluorodeoxyglucose positron emission tomography(18F?FDG PET/CT)in the etiological diag?nosis of postoperative intestinal obstruction in patients with gastrointestinal cancer. Methods A total of 51 patients with postoperative intestinal ob?struction undergone 18F?FDG PET/CT were enrolled for the study. The images were interpreted by visual and semi?quantitative analysis(maximum standard uptake value,SUVmax). All the cases were confirmed by pathology and clinical follow?up for more than half a year. The sensitivity,specifici?ty and accuracy of 18F?FDG PET/CT for detecting malignant intestinal obstruction were calculated. Results Of the 51 patients,35 cases were con?firmed for malignant intestinal obstruction,and 16 cases were caused by other benign diseases. 18F?FDG PET/CT imaging was positive in 36 cases, and 33 cases were diagnosed as malignant and recurrent intestinal obstruction. Three cases of PET false?positive were peritonitis adhesion and anasto?motic inflammation. Two cases of PET false negative were peritoneal micrometastasis. The SUVmax of malignant lesions was 8.86±4.82,and the SUVmax of benign lesions was 2.05±1.95. The uptake of FDG was significantly higher in malignant intestinal obstruction than in benign intestinal obstruction (t=7.15,P<0.01). The sensitivity,specificity,and accuracy of 18F?FDG PET/CT diagnosis of malignant lesion were 94.3%,81.3%,and 90.2%, respectively. Conclusion The uptake of 18F?FDG in malignant intestinal obstruction was higher than that in benign intestinal obstruction. 18F?FDG PET/CT have a good diagnostic value for the intestinal obstruction of postoperative gastrointestinal cancer.

Objective To compare the imaging features of 18F-FDG PET/CT in malignant pleural effusion (MPE) and tuberculosis pleural effusion (TPE).Methods From January 2012 to December 2014,93 patients (52 males,41 females,and average age (66.7±12.7) years) with unexplained pleural effusion who underwent 18F-FDG PET/CT were retrospectively studied.MPE and TPE were confirmed by histology,cytology or clinical follow-up.Lesion SUVmax and T/NT were calculated.Both lesion size and density (in Hounsfield units) of pleural abnormalities on CT images were measured.The difference of images between MPE and TPE was analyzed.Diagnostic efficiency of 18F-FDG PET/CT for detecting MPE and TPE were estimated.Two-sample t test and x2 test were used to analyze the data.Results The lesion SUVmax of 66 patients with MPE and 27 patients with TPE was higher than that in normal tissues (7.72±6.50,8.43±4.92;t=7.81 and 7.15,both P＜0.01),but there was no statistical difference between the TPE and MPE (t=0.56,P＞0.05).T/NT was not significantly different between MPE and TPE (5.40±4.29,5.20±2.73 respectively,t=-0.22,P＞0.05) either.The uptake features of 18F-FDG were different between MPE and TPE (x2=29.3,P＜0.01).When the nodular 18F-FDG uptake increase in pleura was taken as the malignancy,diffuse 18F-FDG uptake increase in pleura as tuberculosis,the sensitivity,specificity,positive predictive value,and negative predictive value of 18F-FDG PET/CT were 78.8％ (52/66),81.5％ (22/27),91.2％ (52/57),61.1％ (22/36),respectively,for differentiation of MPE from TPE.Primary cancers were found in 43 patients.When the nodular uptake increase in pleura,or primary cancer associated with increased pleural uptake found by PET was taken as the malignancy,the above mentioned parameters were95.5％(63/66),81.5％(22/27),92.6％(63/68),88.0％(22/25),respectively.Conclusions The 18FFDG uptake in MPE and TPE is higher than that in normal tissues.18F-FDG PET/CT is helpful in the search for the primary tumor of MPE.Qualitative method of 18F-FDG PET/CT has a good value in the differentiation of MPE from TPE.

Background and purpose:The proportion of incidental thyroid cancer in PET imaging was sig-niifcantly increased with the wide application of18F-FDG PET/CT. The correlation between the glucose metabolism of thyroid incidental thyroid cancer and pathological changes is unclear. The objective of this study is to analyze the relationship between the glucose metabolism by18F-FDG PET/CT and tumor differentiation or lymph node metastasis in patients with incidental thyroid cancer.Methods:A total of 195 patients with focal FDG-avid thyroid incidentaloma during cancer evaluation were enrolled. Fifty-three patients were diagnosed as having thyroid cancer by the pathology. The SUVmax of thyroid cancer foci, lesion size, lesion number, and SUVmax of normal thyroid tissue were quantiifed. The tumor pathological grades and lymph node metastasis were analyzed by the pathology. The patients were broken down into 4 groups (G1, G2, G3 and G4) according to the tumor pathological grades and lymph node metastasis (differentiated thyroid cancer, non-differentiated thyroid cancer, without lymph node metastasis and with lymph node metastasis). The differences of glucose metabolism between G1and G2groups, G3 and G4 groups were analyzed.Results:Fifty-three foci were found by PET imaging. Sixty-two foci were found by the pathology (37 papillary thyroid carcinoma, 4 follicular thyroid carcinoma, 9 medullary thyroid carcinoma, 3 poorly differentiated thyroid cancer). The SUVmax in the normal thyroid tissue, G1and G2were 1.51±0.30, 4.25±1.70 and 6.34±2.45, respectively. The SUVmax in the G1and G2were signiifcantly higher than in the normal thyroid tissue (t=11.0,t=7.10,P<0.01). The SUVmax of G3was 4.77±2.15, and the SUVmax of G4group was 4.67±2.02. The differences between G1and G2groups, G3 and G4groups were not statisti-cally signiifcant (t=3.61,P>0.05;t=0.33,P=0.56).Conclusion:The differentiated incidental thyroid carcinoma and non-differentiated incidental thyroid carcinoma had high glucose metabolism, and there was no signiifcant difference in the levels of glucose metabolism in different differentiation degree and metastasis ability cancer.

Objective:To investigate the distribution of 99Tc m-methylene diphosphonate (MDP) at different stages of bone injury repair. Methods:A total of 30 rabbit models of femur injury were established by the method of electric drill and perforation of femur. According to the different stages of bone injury repair (at 1, 2 and 3 week), rabbits were divided into group A, B and C ( n=10 each group). Femoral SPECT/CT imaging was performed on the last day of different stages of bone injury repair to obtain radioactivity counts in the region of interest (ROI) on the test side and control side and to calculate target/background ratio (T/B). The light intensity of 3 groups was analyzed by phosphor screen imaging and the distribution of 99Tc m-MDP in bone cells was observed by autoradiography. One-way analysis of variance and paired t test were used to analyze the data. Results:The T/B values of group A, B and C were 1.16±0.14, 1.39±0.23 and 1.18±0.10, respectively ( F=5.83, P<0.01). There were significant differences of the maximum radiation count between the test side (50.00±12.45, 59.50±12.83 and 55.10±9.26) and the control side (43.20±9.57, 50.00±12.30 and 44.30± 6.50) in group A, B and C ( t values: 3.24, 2.28 and 5.77, all P<0.05). There were significant differences in the light intensity of bone specimens in group A, B and C by phosphor screen imaging (37 324.67±6 481.50, 60 950.33±9 781.72 and 43 905.00±4 957.92; F=8.25, P=0.02). 99Tc m-MDP were deposited in both intracellular and extracellular during different stages of bone repair in osteocytes and osteoblasts under autoradiography. Conclusion:At different stages of bone injury repair, the concentration of 99Tc m-MDP is significantly distributed, suggesting that there are other ways of concentration mechanism of 99Tc m-MDP in bone tissue besides the chemical adsorption with hydroxyapatite.

Objective:To explore the effect of different glucose concentrations on the uptake of 18F-FDG and the expression of glucose transport protein(Glut)-1 and Glut-3 in non-small cell lung cancer (NSCLC). Methods:NSCLC cell line A549 cells were cultured in DMEM medium with glucose concentrations of 3.9, 5.0, 6.1, 8.3 and 11.1 mmol/L respectively for 24 h. Then 3.7×10 4 Bq 18F-FDG was added into each group and γ counter was used to measure the radioactivity count 1 h later. Western blot was used to examine the expression of Glut-1 and Glut-3. One-way analysis of variance and Bonferroni test were used for data analysis. The correlation was analyzed by Pearson correlation analysis. Results:The 18F-FDG uptake rates in 3.9, 5.0, 6.1, 8.3 and 11.1 mmol/L groups were (4.89±0.83)%, (4.07±0.23)%, (3.66±0.29)%, (3.34±0.16)% and (3.29±0.24)%, respectively ( F=7.05, P=0.006). Compared with 3.9 mmol/L group, the 18F-FDG uptake rates in 8.3 and 11.1 mmol/L groups were reduced and differences were statistically significant ( P values: 0.013, 0.010), while there were no statistical differences between the other groups ( P values: 0.057-0.999). The relative expressions of Glut-1 and Glut-3 in each group were 1.17±0.10, 1.00±0.00, 0.84±0.07, 0.70±0.18, 0.61±0.16, and 1.14±0.05, 1.00±0.00, 0.86±0.12, 0.71±0.05, 0.40±0.06, respectively ( F values: 10.26 and 51.94, P values: 0.001, <0.001). Moreover, the 18F-FDG uptake rates were positively correlated with the expression of Glut-1 and Glut-3 ( r values: 0.775 and 0.744, both P=0.001). Conclusions:When the glucose concentration fluctuates within 3.9-11.1 mmol/L, the change of glucose will affect the 18F-FDG uptake rate and the expression of Glut-1 and Glut-3 in A549 cells. Moreover, the 18F-FDG uptake rate is related to the expressions of Glut-1 and Glut-3.