Objective To investigate MR imaging features of parotid gland in Sj?gren′s syndrome ( SS).Methods Twenty-seven cases of xerostomia patients were collected and divided into SS group ( n=21) and non-SS group (n=6) according to the international classification (diagnosis) criteria for SS.Ten healthy volunteers were recruited as the control group.All the subjects underwent conventional MRI of parotid gland and MR sialography ( MRS).Standard deviation of T 1 WI and T2 WI signal intensity among 3 groups was observed, meanwhile, grading was made according to parotid glands , fat signal and parotid duct expansion degree respectively.With clinical diagnosis as the gold standard , diagnostic value of conventional MRI , MRS and their combination used in SS was compared.One-way ANOVA was used in comparison of standard deviation of parotid gland′s signal intensity among 3 groups , and Chi-square test was applied in comparison of conventional MRI and MRS diagnostic value.Moreover , Kappa value was calculated to assess the consistency of two grading results in SS.Results Signal intensity of parotid glands in control group and non-SS group was homogeneous.However , bilaterally diffused and heterogeneous high signal intensity on both T1WI and T2WI was found in SS patients, which was depressed on T2WI fat suppression sequences.Forty-two parotid glands were graded by fat signal:Grade 0 (n=2 glands), Grade 1 (n=10), Grade 2 (n=10), Grade 3 (n=6) and Grade 4 (n=14).Parotid peripheral ducts of control group and non-SS group were unexpanded , while bilaterally expanded parotid peripheral ducts were shown in SS patients.The grading of 42 parotid glands by expansion degree of parotid duct , Grade 0 was rated in 12, Grade 1 in 8, Grade 2 in 10, Grade 3 in 5, and Grade 4 in 7.Standard deviation of T1WI signal intensity of parotid glands among SS group , non-SS group and control group were 124.1 ±30.0, 81.8 ±27.6, and 86.3 ±35.0 respectively;and standard deviation of T 2 WI signal intensity were 115.1 ±35.2, 69.8 ±23.5, and 80.1 ±31.4 respectively; the standard deviation of T 1 WI and T2 WI signal intensity of SS group was higher than both non-SS group and control group′s ( F value =13.780 and 13.301, respectively, P <0.01), however, the difference of standard deviation of signal intensity of non-SS group and control group had no statistical significance (P>0.05).Among 42 parotid glands with SS, conventional MRI and MRS showed parotid gland lesions in 40 and 30 respectively , and the difference was statistically significant (χ2 =13.04, P=0.013).There was no false positive result.The combination of the two methods detected all 42 lesions.The consistency of detecting parotid abnormalities with SS between conventional MRI and MRS was poor (Kappa=0.12, P=0.092).Conclusions Diffuse fatty infiltration on conventional MRI and diffuse peripheral duct dilatation on MRS in the parotid gland are characteristic features of SS , and conventional MRI could be used as the preferred technique for the SS.combination with MRS may improve diagnostic accuracy.

Objective To compare the PET response criteria in solid tumors (PERCIST) and response evaluation criteria in solid tumors (RECIST) in the evaluation of therapeutic response in 49 non-small-cell lung cancer(NSCLC) patients.Methods Forty-nine NSCLC patients who received chemotherapy but no surgery were studied.Therapeutic responses were evaluated using 18 F-FDG PET and CT according to the RECIST and PERCIST methods.The PET-CT scans were obtained before chemotherapy and about 2 or 6 weeks after completion of chemotherapy.Firstly the reduction rates of tumor diameter and reduction rates of tumor standardized uptake value were compared with paired t-test.Then the response was classed into 4 levels according to RECIST and PERCIST:PD and PMD =1,SD and SMD =2,PR and PMR =3,CR and CMR =4.Pearson and Chi-square test was used to compare the proportion of four levels in RECIST and PERCIST.Finally one target lesion and two target lesions were compared for RECIST therapeutic evaluation in 33 cases with two target lesions.Results The diameter was (3.52 ± 1.65) cm before the therapy and (2.39 ± 1.43)cm after the therapy.The standardized uptake value was 8.78 ±4.18 vs.5.06 ±3.62 before and after therapy for the first target lesions in 49 patients.The differences of reduction rates between tumor diameter and standardized uptake value were not significant because of selection bias (0.32 ± 0.27 vs.0.28 ±0.64,t =0.176,P ＞0.05).However,there was a significant difference when the reduction rate was compared only in 39 patients in which the standardized uptake values were reduced after therapy (0.39 ± 0.29 vs.0.52 ±0.28,t =-4.08,P ＜0.01).The results of classification were 1/13 for CR/CMR,25/16 for PR/PMR,22/15 for SD/SMD,1/5 for PD/PMD,and 33 cases had no consistent results from RECIST and PERCIST.There was a significant difference in response classification between RECIST and PERCIST (x2 =16.252,P ＜ 0.01).No significant difference was found between one target lesion and two target lesions for RECIST evaluation results in 33 cases (x2 =1.171,P ＞ 0.05),but results of response classification were changed in 5 cases.Conclusions PERCIST criteria may be more sensitive in NSCLC therapeutic evaluation comparing to RECIST criteria.There is a higher proportion with CMR and PMD in PERCIST,but its effect on the prognosis is not yet clear.The number of target lesions may affect the results of therapeutic evaluation with RECIST criteria.

2 cm).Immunohistochemistrical stain slice of operative specimen showed a lots of vascular endothelial cells and small vessels,which correlated with the tumor angioimaging area on CT images.The sensitivity,specificity,and positive predictive valve of tumor angioimaging in the lung cancers were 47.2%,91.3%,and 95.5%,respectively.Conclusion The “tumor angioimaging” sign can be regarded as another specific feature in peripheral lung cancer with contrast CT.

Objective To investigate the clinical value of 18F-FDG PET/CT in staging,therapeutic response evaluation,relapse early detection and prognostic prediction of follicular lymphoma (FL).Methods Twenty-eight patients (12 males,16 females; average age 57 (36-82) years) with pathologically confirmed FL from December 2005 to January 2013 were enrolled.All patients underwent 18F-FDG PET/CT before treatment.The SUVmax of different staging groups,different pathological grade groups (high:3a+3b; low:1+2) was compared.Seventeen of 28 patients underwent PET/CT after chemotherapy and received phone follow-up (10-88 months) to monitor the progress of treatment.Survival difference was analyzed.Mann-Whitney u test,Wilcoxon signed-rank test and Kaplan-Meier survival analysis were used for data analysis.Results (1) The initial clinical staging without 18F-FDG PET/CT based on Ann Arbor standard changed in 4 cases (up-staging in 3 cases,down-staging in 1 case) after the PET/CT scan.The 18F-FDG uptake (SUVmax) in patients of stage Ⅰ/Ⅱ and stage Ⅲ/Ⅳ was 10.1±3.2 and 11.5±4.9,respectively (Z=-0.619,P＞0.05).The SUVmax in patients of the low grade group (6.9±3.6,n=15) was significantly lower than that of the high grade group (12.4±5.6,n=13) (Z=-3.706,P＜0.01).(2) 17 patients underwent PET/CT scan both before and after chemotherapy,the pre-treatment SUVmax and post-treatment SUVmax were significantly different in CR+PR group (10.8±5.1 vs 3.4±2.3; Z=-2.312,P＜0.05),while there was no significant difference in SD+PD group (11.2±6.9 vs 7.8±3.3; Z=-1.153,P＞0.05).There was a significant difference in the median progress-free survival time between the CR+PR group and the SD+PD group (48 months vs 26 months; x2 =4.207,P＜0.05).Conclusion 18F-FDG PET/CT has an advantage in clinical staging,therapeutic evaluation,relapse monitoring and prognosis predicting of FL.

Objective To investigate the prognostic value of interim and post-therapy 18F-FDG PET/CT in patients with DLBCL.Methods A retrospective analysis was conducted in 110 patients (62males,48 females; median age 52 years) with newly diagnosed DLBCL.Forty-two patients underwent interim PET/CT after 4 cycles chemotherapy,44 patients underwent post-therapy PET/CT after 6-8 cycles of chemotherapy,and 24 patients underwent both interim PET/CT and post-therapy PET/CT.Interim and post-therapy PET/CT status (i.e.,positive or negative) were visually interpreted according to criteria of the International Harmonization Project.Three-year progression-free survival (PFS) and 3-year overall survival (OS) was compared between the subjects with positive or negative PET/CT results.x2 test and KaplanMeier analysis were used for data analysis.Results Interim 18F-FDG PET/CT results were positive in 28cases and negative in 38 cases.The median PFS and OS were 20 and 28 months in patients with positive scan results,those were 37 and 39 months in patients with negative results,respectively.Three-year PFS and 3-year OS rates were 17.9％(5/28) and 35.7％(10/28) in patients with positive interim PET/CT results,those were 52.6％ (20/38) and 55.3％ (21/38) in patients with negative results (x2 =8.285,P ＜0.01,x2=2.473,P＞0.05,respectively).Post-therapy 18F-FDG PET/CT results were positive in 20 cases and negative in 48 cases.Median PFS and OS were 21 and 26 months in patients with positive results,those were 54 and 57 months in patients with negative results.Three-year PFS and 3-year OS rates were 20.0％(4/20) and 25.0％ (5/20) in patients with positive results at post-therapy PET/CT,those were 77.1％(37/48) and 83.3％ (40/48) in patients with negative results (x2=19.215,21.462,both P＜0.01).Conclusions Post-therapy 18F-FDG PET/CT is useful to predict prognosis of patients with DLBCL.However,the value of interim PET/CT may be limited in terms of prognosis prediction.

Objective To summarize the imaging manifestations of 18F-FDG PET/CT in patients with secondary hemophagocytic lymphohistiocytosis (sHLH).Methods From January 2008 to June 2012,31 patients (18 males,13 females,average age:42 years) with sHLH were enrolled.All patients were divided into 3 groups:malignancy associated HLH (MAHLH) group (n =13),infection associated HLH (IAHLH) group (n =13) and rheumatosis associated HLH (RAHLH) group (n =5).They all underwent 18F-FDG PET/CT and SUVmax of lesions in each group was calculated.One-way analysis of variance and two-sample t test were used to analyze the SUVmax.Results Twenty-three patients were found splenomegaly with high FDG uptake,including 4 RAHLH patients,9 IAHLH patients and 10 MAHLH patients.The splenetic FDG uptake values (SUVmax) of RAHLH,IAHLH and MAHLH groups were 3.16±0.61,5.67±3.37 and 6.04±3.06,respectively (F=1.051,P＞0.05).The SUVmax of enlarged lymph nodes in IAHLH (n=8) and MAHLH groups (n =7) was 5.35± 1.69 and 10.14±5.24,respectively (t =-2.456,P＜0.05).Increased uptake in bone marrow was found in 17 patients,including 1 RAHLH patient,7 IAHLH patients and 9 MAHLH patients.The SUVmax of bone marrow in IAHLH and MAHLH patients was 5.31±2.05 and 6.36± 3.71 respectively (t=-0.670,P＞0.05).There were 10 cases of hepatomegaly,but only 4 of them had intense FDG uptake (SUVmax 4.9-10.2).The SUVmax of RAHLH,IAHLH and MAHLH groups was 3.02± 1.31,5.62±2.45 and 8.15±4.38,respectively (F=9.123,t=2.562,5.236,3.030,all P＜0.05).Conclusions RAHLH mostly showed splenomegaly with high FDG uptake,IAHLH and MAHLH both showed splenomegaly with lymph node and bone marrow invasion.The SUVmax of MAHLH was the highest.18F-FDG PET/CT imaging manifestations of sHLH may be helpful to improve the diagnostic accuracy.

Objective To evaluate the clinical value of 18F-FDG PET-CT in monitoring response to therapy in patients with follicular lymphoma (FL) staging Ⅲ-Ⅳ.Methods The clinical data of 20 patients with FL were analyzed retrospectively.All patients underwent PET-CT at three times:baseline,after 3-4 cycles of chemotherapy,and end of treatment.Kaplan-Meier method was used to analyze the survival of patients.Results 14 patients achieved CR at the interim PET-CT,all patients achieved CR at post therapy PET-CT:all patients were alive with no evidence of disease in the follow-up.2 patiens achieved PR at the interim PET-CT,and 1 patient achieved CR,and 1 patient was PD,at post therapy PET-CT,all patients were relapsed in the follow-up.4 patients achieved PD,and all patients were changed the chemotherapy plan.At post therapy PET-CT,2 patients achieved CR,1 patient achieved PR,and 1 patient was PD,1 patient was no evidence of disease,2 patients were relapsed,and another was died in the follow-up.The negative predictive values (NPV) of the interim and the post therapy PET-CT were 100 ％ (14/14),88.2 ％ (15/17) respectively.The interim PET-CT was no significantly correlated with PFS (P =0.135),while the post therapy PET-CT was significantly correlated with PFS (P =0.0006).Conclusion 18F-FDG PET-CT is useful to monitor response to chemotherapy in patients with FL staging Ⅲ-Ⅳ,and set personalized treatment plan.

Objective To assess the value of CT or PET-CT with fluorine-18-labeled fluorodeoxyglucose (FDG) for the diagnosis of pulmonary mucosa-associated lymphoid tissue (MALT) type lymphoma. Methods The CT or FDG PET-CT findings in 14 patients with pathologically proved pulmonary MALT lymphoma were retrospectively analyzed. Results Lung lesions were unilateral in 7 patients and bilateral in 7 patients. Lesions presented as a single mass in 3 patients, as a single consolidation in 3 patients, as a nodule in 1 patient, as multiple nodules in 1 patient, as multiple patchy consolidations in 4 patients, as a mass with multiple nodules and patchy consolidations in 1 patients, as diffuse interstitial change in 1 patients. Air bronchogram was found in 9 patients and CT angiogram sign in 5 patients. On PET-CT, lesions showed heterogeneous FDG uptake in 2 patients, maximum standard uptake value was higher than 2. 5. Conclusion Imaging characteristics of pulmonary MALT lymphoma are single or multiple nodules or consolidations with air bronchogram on CT, and heterogeneous high FDG uptake on PET-CT.

Objective To investigate the prognostic value of interim and post-therapy 18fluorine-fluododeoxyglucose(18F-FDG) PET-CT in patients with T-cell lymphoma.Methods A retrospective analysis was conducted on data from 50 patients diagnosed with T-cell lymphoma(12 patients underwent interim PET-CT only,19 patients underwent interim and post-therapy PET-CT,and the rest 19 patients underwent only post-therapy PET-CT).Interim and post-therapy PET-CT(positive versus negative) were visually interpreted according to the criteria of the International Harmonization Project.The progression-free survival (PFS) and overall survival(OS) of two groups were calculated.We used the Fisher exact test and KaplanMeier testfor data analysis.Results Interim 18F-FDG PET-CT results were positive in 19 cases and negative in 12 cases.The median PFS and OS were 8 months and 16 months,in patients with positive results,versus 30 months and 36 months,in patients with negative results.The 1-year PFS and 3-year OS rates were 21.1％ (4/19) and 10.5％(2/19) in patients with positive results at interim PET/CT versus 100.0％(12/12) and 66.7％ (8/12) in patients with negative results(P＜0.01.Post-therapy 18F-FDG PET-CT results were positive in 16 cases and negative in 22 cases,the median PFS and OS were 10 months and 20 months in patients with positive results versus 32 months and 41 months in patients with negative results.The 1-year PFS and 3-year OS rates were 12.5％(2/16) and 12.5％(2/16),in patients with positive results at post-therapy PET-CT versus 95.5％(21/22) and 54.5％(12/22),in patients with negative results(P＜0.01).Conclusion Both interim PET-CT status and post-therapy PET-CT have significant value in monitoring response to therapy and predicting prognosis for patients with T-cell lymphoma.

Objective To evaluate accuracy of density measurements within coronary plaque by multi-slice spiral CT and factors that influence measurements. Methods Four adult cadaver hearts were used. Thrombus and pericardial fat which acquired from specimen (size 2.0, 1.5, 1.0 and 0.5 mm respectively) were placed into coronary artery to simulate coronary plaques. The contrast medium (three different concentrations 1: 30, 1:40, and 1:50) were injected into coronary artery. The raw date were reconstructed with two slice width ( 1. 00 and 0. 75 mm). Results When contrast medium concentrations was 1: 30, the CT values of thrombus were 109 HU ( slice width 1. 00 mm, size 2. 0 mm) , 115 HU ( slice width 1.00 mm, size 1.5 mm), 101 HU (slice width 0.75 mm, size 2.0 mm), 113 HU ( slice width 0. 75 mm,size 1. 5 mm) ; the CT values of fat were - 23 HU ( slice width 1. 00 mm, size 2. 0 mm) , -17 HU(slice width 1.00 mm, size 1.5 mm) , -9 HU(slice width 1.00 mm, size 1.0 nun), -27 HU ( slice width 0.75 mm, size 2. 0 mm) , - 19 HU (slice width 0.75 mm, size 1. 5 mm) , - 13 HU (slice width 0. 75 mm,size 1. 0 mm). When contrast medium concentrations was 1: 40, the CT values of thrombus were 79 HU( slice width 1.00 mm,size 2.0 mm) , 87 HU( slice width 1.00 mm, size 1. 5 mm) , 115 HU( slice width 1. 00 mm,size 1. 0 mm) , 73 HU(slice width 0. 75 mm,size 2. 0 mm) , 80 HU(slice width 0. 75 mm, size 1. 5 mm) , 110 HU( slice width 0. 75 mm, size 1. 0 mm) ; the CT values of fat were - 31 HU ( slice width 1. 00 mm, size 2. 0 mm) , - 22 HU ( slice width 1. 00 mm, size 1. 5 mm) , - 10 HU ( slice width 1.00 mm,size 1.0 mm) , -35 HU(slice width 0. 75 mm,size 2.0 mm) , -25 HU(slice width 0. 75 mm, size 1. 5 mm) , - 19 HU ( slice width 0. 75 mm, size 1. 0 mm). When contrast medium concentrations was 1:50, the CT values of thrombus were 53 HU ( slice width 1. 00 mm, size 2. 0 mm) , 60 HU ( slice width 1.00 mm,size 1.5 mm) ,63 HU(slice width 1.00 mm,size 1.0 mm) ,51 HU(slice width 0.75 mm,size 2. 0 mm) ,64 HU( slice width 0. 75 mm,size 1. 5 mm) ,67 HU( slice width 0. 75 mm,size 1. 0 mm) ,145 HU (slice width 0. 75 mm, size 0. 5 mm) ; the CT values of fat were - 39 HU ( slice width 1. 00 mm, size 2. 0 mm) , -28 HU( slice width 1. 00 mm,size 1. 5 mm) , - 22 HU( slice width 1. 00 mm,size 1. 0 mm) , 17 HU(slice width 1. 00 mm,size 0. 5 mm) , -41 HU(slice width 0. 75 mm,size 2. 0 mm), -36 HU(slice width 0. 75 mm, size 1. 5 mm ) , - 27 HU ( slice width 0. 75 mm, size 1. 0 mm ) , 3 HU ( slice width 0. 75 mm, size 0. 5 mm ) . The density values of thrombus were correlated with size ( t = - 6. 624, P 0. 05) not found statistically significant may be caused by both too close slice width (1.0 mm and 0. 75 mm) and few samples. The slice width(t= -2. 595,P