Objective To investigate the radiation dose delivered to the patients with dense breasts and the influence of photographic conditions on image quality in full field digital mammography (FFDM).Methods (1) Clinical test:we analyzed the compression thickness of breasts,Target-filter(T-F),voltage current (kV),tube current (mAs),average glandular dose (AGD) and entrance surface dose (ESE) of 100 patients (a total of 370 images,277 images of Molybdenum-Rhodium(Mo-Rh)and 93 images of Wolfram-Rhodium (W-Rh)) who underwent examinations in mode of automatic exposure by FFDM with dense breasts.(2) Phantom experiments:placed the Aluminium plate on different thickness of polymethyl methacrylate (PMMA) plates to simulate the dense breasts.68 mm phantom was used to simulate photographic condition of W-Rh and 58 mm to Mo-Rh.The two groups of dense phantom were exposed automatically and manually.The parameters were recorded for each exposure including the compression thickness of breasts,T-F,kV,mAs,AGD,ESE,the calculation of the ratio between ESE and AGD (ESE/AGD).The image quality figure inverse (IQFInv) was obtained by software.To the clinical test,used multiple factors of variance to analyze the influence of compression thickness and mAs on AGD and ESE,Pearson correlation and regression to analyze the influence of compression thickness on ESE/AGD.To the phantom experiments,used Pearson correlation to analyze the influence of kV and mAs on AGD,ESE and ESE/AGD,single factor of variance to analyze the influence of kV and mAs on IQFInv.Results (1) Clinical test:to Mo-Rh and W-Rh,with the increase of compression thickness,ESE/AGD was increased significantly.Compression thickness had linear relationship with ESE/AGD.Pearson correlation coefficients of W-Rh and Mo-Rh were 0.956 and 0.980,respectively(P＜0.01).The effects of compression thickness and mAs on AGD and ESE were statistically significant (P＜0.05) in the two groups.(2)Phantom experiments:adjusted exposure parameters to the two dense phantoms of W-Rh and Mo-Rh.With the increase of mAs and kV,IQFInv was increased in W-Rh and Mo-Rh.Different mAs and kV were statistically significant (P＜0.05) on IQFInv,mAs and kV had positive correlation with ESE and AGD (P＜0.05),mAs and kV had different correlation with ESE/AGD in the two dense phantoms.Conclusions In mode of automatic exposure by FFDM,choosing W-Rh can achieve relatively high image quality and lower radiation dose.According to the results of phantom experiments,adjusting kV and mAs properly in manual exposure can reduce AGD and ESE effectively and ensure the quality of the image.

Objective:To evaluate the value of the crescent sign for predicting the invasiveness of lung adenocarcinoma presenting as pure ground-glass nodule (pGGN).Methods:The clinical, pathological and imaging data of 316 patients (320 pGGNs) confirmed lung adenocarcinoma by surgery and pathology from July 2013 to June 2018 in the First Affiliated Hospital of Wenzhou Medical University were retrospectively analyzed. All pGGNs were divided into preinvasive group (148 pGGNs) and invasive group (172 pGGNs) according to histopathology. Logistic regression analysis was used to determine the risk factors for invasiveness of pGGN, and the ROC curve analysis was performed on each risk factor.Results:Crescent sign was found in 24 cases (16.2%) in the preinvasive group and 49 (28.5%) in the invasive group, and the difference between the two groups was statistically significant (χ2=6.804 ,P=0.009).There were statistically significant differences in patient′s age, lesion size, shape, lobulation sign, and vascular stretch sign between the two groups ( P<0.05). The ROC curve showed that with the lesion size 10.5 mm as the optimal cut off value, the sensitivity for differential diagnosis of preinvasive and invasive lesions was 65.7%, the specificity was 61.5%, and the area under the curve was 0.666. Logistic regression analysis showed that maximum diameter of the lesion ≥10.5 mm, irregular shape, crescent sign and vascular stretch were independent risk factors of invasiveness of pGGN, and the OR value (95%CI) were 3.192 (1.981-5.144), 3.672 (1.545-8.725), 1.972 (1.104-3.521), and 2.026 (1.087-3.777), respectively. A logistic model was established based on the above four independent risk factors, and the area under curve was 0.711 (95%CI 0.655-0.768). Conclusion:Crescent sign can effectively reflect the invasiveness of pGGN. Maximum diameter of the lesion ≥10.5 mm, irregular shape, crescent sign and vascular stretch sign are independent risk factors of invasiveness of pGGN.

Objective To evaluate the CT features of small lung invasive adenocarcinoma with air?containing space and its relationship with pathological types, and to explore the pathological basis of air?containing space. Methods CT and pathological data of fifty patients with surgically proven lung invasive adenocarcinoma with air?containing space in our hospital from January 2012 to December 2017 were retrospectively reviewed. CT image analysis included image features of tumor and air?containing space. Pathological analysis included pathological subtype, differentiation degree. CT features of tumor and air?containing space were compared with regard to pathological types using chi?square test or Fisher exact text. Analysis of variance was used to compare quantitative data satisfying normal distribution, while those data not satisfying normal distribution were compared with Kruskal?Wallis test. In addition, Spearman correlation was used to analyze the correlation between nodule density and pathological types. Results (1) CT features of tumors: Tumors were predominantly located in peripheral lungs (46/50). Most of the tumors were subsolid nodules (37/50). Tumor?lung interface was generally clear (46/50). Tumors are often accompanied by malignant signs such as lobulation (37/50), spicule sign (27/50), air bronchogram sign (43/50), and pleural indentation (36/50). The mean diameter of nodules ranged from 7.50 mm to 18.12 mm, with an average of (12.91±2.85)mm. The nodule density ranged from-657.00 to 73.00 HU with an average of (-213.88±206.16) HU. (2) CT features of air?containing space:Air?containing spaces were commonly solitary (37/50) and were found to be mainly in an eccentric distribution (29/37). The maximum diameter of air?containing space ranged from 1.00 to 16.00mm, and the average diameter was (4.23±3.14)mm. Air?containing spaces less than 5mm were found in 35 cases (70%), and air?containing spaces more than 5mm were found in 15 cases. (3) Comparison of CT features and corresponding pathological types: Nodule density, number of air?containing space, and type of nodule density in different pathological types were statistically different (P<0.05). There was a correlation between nodule density and pathological subtypes (r=0.371, P=0.008). Differences of nodule density, short?dimension of nodule, type of nodule density, spicule sign, pleural indentation among different tumor differentiation degrees were significant (P<0.05). The degree of tumor differentiation was negatively correlated with nodule density (r=-0.451, P=0.001). Conclusion The detection rate of air?containing space in lung invasive adenocarcinomas is 12.7%. Most small lung invasive adenocarcinomas with air?containing space are presented as peripheral subsolid nodule, and there is a certain correlation between their CT features and pathological types. The pathological basis of air?containing space was supposed to be dilated distal bronchiole induced by check?valve mechanism and destruction of alveolar structure by tumor.

Objective: To evaluate the CT features of small lung invasive adenocarcinoma with air-containing space and its relationship with pathological types, and to explore the pathological basis of air-containing space. Methods: CT and pathological data of fifty patients with surgically proven lung invasive adenocarcinoma with air-containing space in our hospital from January 2012 to December 2017 were retrospectively reviewed. CT image analysis included image features of tumor and air-containing space. Pathological analysis included pathological subtype, differentiation degree. CT features of tumor and air-containing space were compared with regard to pathological types using chi-square test or Fisher exact text. Analysis of variance was used to compare quantitative data satisfying normal distribution, while those data not satisfying normal distribution were compared with Kruskal-Wallis test. In addition, Spearman correlation was used to analyze the correlation between nodule density and pathological types. Results: (1) CT features of tumors: Tumors were predominantly located in peripheral lungs (46/50). Most of the tumors were subsolid nodules (37/50). Tumor-lung interface was generally clear (46/50). Tumors are often accompanied by malignant signs such as lobulation (37/50), spicule sign (27/50), air bronchogram sign (43/50), and pleural indentation (36/50). The mean diameter of nodules ranged from 7.50 mm to 18.12 mm, with an average of (12.91±2.85)mm. The nodule density ranged from-657.00 to 73.00 HU with an average of (-213.88±206.16) HU. (2) CT features of air-containing space: Air-containing spaces were commonly solitary (37/50) and were found to be mainly in an eccentric distribution (29/37). The maximum diameter of air-containing space ranged from 1.00 to 16.00mm, and the average diameter was (4.23±3.14)mm. Air-containing spaces less than 5mm were found in 35 cases (70%), and air-containing spaces more than 5mm were found in 15 cases. (3) Comparison of CT features and corresponding pathological types: Nodule density, number of air-containing space, and type of nodule density in different pathological types were statistically different (P<0.05). There was a correlation between nodule density and pathological subtypes (r=0.371, P=0.008). Differences of nodule density, short-dimension of nodule, type of nodule density, spicule sign, pleural indentation among different tumor differentiation degrees were significant (P<0.05). The degree of tumor differentiation was negatively correlated with nodule density (r=-0.451, P=0.001). Conclusion The detection rate of air-containing space in lung invasive adenocarcinomas is 12.7%. Most small lung invasive adenocarcinomas with air-containing space are presented as peripheral subsolid nodule, and there is a certain correlation between their CT features and pathological types. The pathological basis of air-containing space was supposed to be dilated distal bronchiole induced by check-valve mechanism and destruction of alveolar structure by tumor.

Objective: To explore the value of dual-energy CT-based volumetric iodine-uptake (VIU) in the evaluation of chemotherapy efficacy in advanced gastric cancer. Methods: Inclusion criteria of subjects: (1) without previous systematic therapy; (2) with complete clinical information before and after chemotherapy; (3) without contraindications of chemotherapy. Exclusion criteria of subjects: (1) unfinished duration and times of chemotherapy; (2) unmeasurable primary lesions; (3) poor imaging quality or poor gastric filling. Clinical and image data of 52 patients with advanced gastric cancer who were diagnosed by pathology from gastroscopic biopsy, and needed chemotherapy evaluated by imaging and clinical information in the First Affiliated Hospital of Wenzhou Medical University from February 2017 to February 2018 were collected and analyzed. Of 52 patients, 38 were male and 14 were female with the median age of 65 (31-88) years old. All the patients underwent a dual-energy, dual phase-enhanced CT scanning before chemotherapy and after the third chemotherapy session. The parameters of the lesions measured before and after chemotherapy in portal vein phase were as follows: the maximum diameter (the largest diameter among those measured in the cross-sectional, coronal, and sagittal planes), average CT value (the regions of interest were manually pinpointed under cross-sectional planes with largest diameter of the tumor, which did not include regions less than 2 mm to the edge of the tumor) and VIU (lesion volume × iodine concentration). The change rates of maximum lesion diameter, average CT value and VIU before and after chemotherapy were calculated [(post-chemotherapy parameters-pre-chemotherapy parameters)/ pre-chemotherapy parameters]. The efficacy of chemotherapy was evaluated by RECIST 1.1 (the change of maximum tumor diameter after chemotherapy), Choi (the change of average CT value after chemotherapy) and VIU (the change of VIU after chemotherapy), respectively, which was categorized by complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Patients with CR, PR, and SD were assigned to the effective group, while those with PD were classified as the ineffective group. Paired t - test or Wilcoxon signed ranks test was used to compare the changes of parameters before and after chemotherapy, whereas Spearman correlation analysis and Kappa test were used for the correlation analysis and the consistency test between the three evaluation criteria (Kappa≥0.75 indicated good consistency). Results: After chemotherapy, the average CT value [(74.01±16.75) HU vs. (81.06±15.87) HU, t=2.202, P=0.030] and median VIU (668.53×10² μg vs. 272.52×10² μg, Z=4.761, P<0.001) decreased significantly, while the difference of the maximum diameter was not statistically significant [(66.71±34.49) mm vs. (78.45±35.62) mm, t=1.708, P=0.091]. The median change rate of VIU (–53.33%) was greater than that of CT values (–5.75%) with significant difference (Z=-5.408, P<0.001). According to the RECIST 1.1 criteria, 47 patients (90.4%, including 19 with PR and 28 with SD) were effective and 5 patients (9.6%) were ineffective. According to the Choi criteria, 45 patients (86.5%, including 37 with PR and 8 with SD) were effective and 7 patients (13.5%) were ineffective. According to the VIU criteria, 46 patients (88.5%, including 41 with PR and 5 with SD) were effective and 6 patients (11.5%) were ineffective. Efficacy comparison among these three criteria showed no significant difference (χ²=0.377, P=0.828). As compared to RECIST 1.1 evaluation, the proportion of PR evaluated by Choi and VIU was significantly higher (χ²=16.861, P<0.001), whereas the proportion of SD was significantly lower (χ²=24.089, P<0.001). There was no significant difference in the proportions of PR and SD between VIU and Choi criteria (χ²=0.887, P=0.346). Consistency and correlation analysis showed that the VIU and Choi evaluation criteria presented the highest consistency and correlation (Kappa=0.912, P<0.001; r=0.916, P<0.001). Conclusion VIU is a feasible parameter for the evaluation of chemotherapy efficacy in advanced gastric cancer, and may be more sensitive than the evaluation criteria based on maximum diameter or change of CT value in the tumor.