Objective:To develop a mesenteric creeping fat index (MCFI) based on CT enterography (CTE) to characterize the degree of creeping fat wrapping around the inflamed gut in Crohn disease (CD), and to assess the relationship between MCFI and the inflammatory intestinal stricture.Methods:From December 2018 to July 2019, the patients with CD who underwent surgery in the First Affiliated Hospital of Sun Yat-Sen University were prospectively collected. The extent of perienteric mesenteric vessels wrapping around the gut was reconstructed to develop MCFI based on CTE images. The intestinal stricture index was obtained by calculating the ratio of the maximal upstream luminal diameter divided by the minimum luminal diameter apparent within the stricturing region. Using region-by-region correlation between CTE and surgical specimen, creeping fat score in intestinal specimen was obtained by assessing the extent of creeping fat wrapping around the resected bowel segment, and HE staining was performed on the bowel specimen corresponding to creeping fat to obtain the pathological inflammatory score. The Spearman correlation analysis was used to evaluate the correlation between MCFI, creeping fat score in intestinal specimen, and inflammatory score, intestinal stricture index. The ROC curve analysis was used to assess the accuracy of MCFI in distinguishing moderate-severe and mild inflammatory bowel walls.Results:Totally 30 CD patients were enrolled. The creeping fat score in intestinal specimen positively correlated with pathological inflammatory score ( r s=0.403, P=0.027) and with intestinal stricture index ( r s=0.642, P<0.001). MCFI positively correlated with creeping fat score in intestinal specimen ( r s=0.840, P<0.001), with pathological inflammatory score ( r s=0.497, P=0.005), and with intestinal stricture index ( r s=0.599, P<0.001). ROC analysis showed that the area under the curve of MCFI for differentiating moderate-severely from mildly inflammatory bowel walls was 0.718 (95%CI 0.522-0.913). Using MCFI≥4 as a cutoff value, the sensitivity and specificity were 81.8% and 47.4%, respectively. Conclusions:There was a correlation between creeping fat and inflammatory intestinal strictures in CD. MCFI can non-invasively depict the degree of creeping fat wrapping around the gut and assess the inflammatory intestinal stricture.

Inflammatory bowel disease (IBD) mainly includes Crohn′s disease (CD) and ulcerative colitis (UC) . The imaging diagnosis of CD is difficult because of its complex disease and varied imaging manifestations. Standardizations of imaging techniques and reports are helpful to improve the imaging diagnosis level of CD. This article aims to provide guideline for the imaging technique selection, scanning scheme formulation, imaging features interpretation and imaging report writing of CD in China.

Inflammatory bowel disease (IBD) mainly includes Crohn′s disease (CD) and ulcerative colitis (UC) . The imaging diagnosis of CD is difficult because of its complex disease and varied imaging manifestations. Standardizations of imaging techniques and reports are helpful to improve the imaging diagnosis level of CD. This article aims to provide guideline for the imaging technique selection, scanning scheme formulation, imaging features interpretation and imaging report writing of CD in China.

Objective:To investigate the epidemiological characteristics for family clusters of COVID-19 in Zhejiang Province.Methods:The data including cases information of asymptomatic infected cases of family clusters of COVID-19 in Zhejiang Province were collected from Public Health Emergencies Reporting System of China Center for Disease Control and Prevention. Calculate the case number of subsequent cases, index cases, asymptomatic infected cases, exposure cases, and then, compute family secondary attack rate (SIR) and serial interval.Results:A total of 389 cases comprised 149 family index cases and 240 subsequent cases. The clinical symptoms between family index cases and subsequent cases (exclude asymptomatic infected cases ) were similar, fever was the most common symptoms in the two groups 115 (77.18%) and 110（48.67%）respectively, the cases with diarrhea symptoms accounted for the least proportion, which were 7 (4.70%) and 6 (2.65%) respectively. The serial interval between the family index cases and the subsequent cases [ M ( P25, P75)] was 4.00 (2.00, 6.00) days. Family secondary attack rate for subsequent cases was 34.43%, subsequent cases aged between 14 and 60 have the highest SIR (43.42%) compared with other two age groups, the difference was statistically ( P<0.001); the family SIR of the spouses of the family index cases is 68.57%, and are higher than that of parents (29.03%), children (25.00%) and other family members (24.21%), the difference was also statistically ( P<0.001). Conclusion:2019 novel coronavirus has shorter serial interval and higher family SIR, the SIR of spouses is higher than other family members.

Objective:To investigate the epidemiological characteristics for family clusters of COVID-19 in Zhejiang Province.Methods:The data including cases information of asymptomatic infected cases of family clusters of COVID-19 in Zhejiang Province were collected from Public Health Emergencies Reporting System of China Center for Disease Control and Prevention. Calculate the case number of subsequent cases, index cases, asymptomatic infected cases, exposure cases, and then, compute family secondary attack rate (SIR) and serial interval.Results:A total of 389 cases comprised 149 family index cases and 240 subsequent cases. The clinical symptoms between family index cases and subsequent cases (exclude asymptomatic infected cases ) were similar, fever was the most common symptoms in the two groups 115 (77.18%) and 110（48.67%）respectively, the cases with diarrhea symptoms accounted for the least proportion, which were 7 (4.70%) and 6 (2.65%) respectively. The serial interval between the family index cases and the subsequent cases [ M ( P25, P75)] was 4.00 (2.00, 6.00) days. Family secondary attack rate for subsequent cases was 34.43%, subsequent cases aged between 14 and 60 have the highest SIR (43.42%) compared with other two age groups, the difference was statistically ( P<0.001); the family SIR of the spouses of the family index cases is 68.57%, and are higher than that of parents (29.03%), children (25.00%) and other family members (24.21%), the difference was also statistically ( P<0.001). Conclusion:2019 novel coronavirus has shorter serial interval and higher family SIR, the SIR of spouses is higher than other family members.

Objective To determine the correlation between intravoxel incoherent motion (IVIM) parameters and both histologic inflammatory and fibrotic grades of Crohn disease (CD) in adults. Methods Prospectively, 17 patients (77 lesions) with a clinical and pathological diagnosis of CD in the first affiliated hospital of sun yat-sen university from July 2015 to June 2016 underwent MRE 15 days before surgery. All patients underwent T2WI, IVIM and enhanced MRI and calculated IVIM parameters include diffusion-related coefficient (D), perfusion-related coefficient (D*) and perfusion-related fraction (f). Histological intestinal inflammation and fibrosis was scored using the surgical histopathology as reference standard and further divided into mild-moderate (score 1 to 2) and severe (score 3 to 4) groups. Intestinal microvessel density (MVD) were also analyzed. Differences in IVIM parameters among different histological inflammation and fibrosis grades were assessed with the Kruskal-Wallis test. The Wilcoxon test was used for assessing differences in f between mild-moderate and severe fibrosis. The bivariate correlations between IVIM parameters and histological inflammation and fibrosis grades were analyzed using partial correlation . The bivariate correlations between IVIM parameters and MVD were analyzed using Spearman rank correlation. The areas under the receiver operating characteristics curves (AUROC) were analyzed to evaluate the efficacy for distinguishing severe from mild-moderate fibrosis. Results Of 77 surgical specimens, there were 41 mild-moderate and 36 severe inflammatory bowel segments, along with 22 mild-moderate and 55 severe fibrotic bowel segments. Positive correlation was shown between histologic inflammatory and fibrotic scores (r=0.592, P<0.01). MVD (42.7 ± 39.9)/HP presented weak positive correlation with histologic inflammatory scores (r=0.332, P=0.003) while no correlation with histologic fibrotic scores (r=0.129, P=0.262) was presented. Neither the D nor the D* values significantly correlated with histologic inflammation or fibrosis (P>0.05) while the f value significantly correlated with both histologic inflammation and fibrosis (P<0.05). Significant correlation was present between the f value and histologic inflammatory and fibrotic scores, respectively (r=-0.280, -0.520;P<0.05). There was significant difference in the f value between mild-moderate and severe fibrosis(Z=-5.255,P<0.01). The AUROC for the f value to distinguish between patients with mild-moderate fibrosis and severe fibrosis were 0.885. Using a threshold fractional perfusion of 0.33, the sensitivity and specificity values were 95.5％ and 81.8％, respectively. No correlation between f, D and D*value with histologic fibrotic scores (r=0.129, P=0.262) was presented. Conclusion The f value derived from IVIM could help to evaluate the severity of intestinal inflammation and fibrosis CD in adults.

OBJECTIVETo compare the difference of the diameters of superior mesenteric vein (SMV) and gastrocolic trunk (GCT) between patients with cecum-ascending colon cancer and normal individuals, and to assess the diagnostic value of the diameters of SMV and GCT in cecum-ascending colon cancer.

METHODSPreoperative imaging data of 60 patients with primary cecum-ascending colon cancer confirmed by postoperative pathology at the First Affiliated Hospital of Sun Yat-sen University from June 2014 to December 2016 were retrospectively analyzed. The diameters of SMV and GCT were measured on preoperative CT images. SMV was measured at about 2 cm below the junction of SMV and splenic vein. GCT was measured at 1 cm near the proximal junction of right colon vein, right gastroepiploic vein and anterior pancreaticoduodenal vein. Another 60 people receiving pelvic CT examination without organ illness were collected as control. The diameter differences of SMV and GCT between cancer group and control group were compared. The diagnostic value of the diameters of SMV and GCT in cecum-ascending colon cancer was evaluated by receiver operating characteristic (ROC) curves.

RESULTSAmong 60 cases of cecum-ascending colon cancer, 36 were males and 24 were females with median age of 48 years (range 28-84); 13 were cecum cancer, 47 were ascending colon cancer; 11 had no lymph node and liver metastasis, 40 had lymph node metastasis, 9 had liver metastasis (all with lymph node metastasis). Compared to control group, the diameters of SMV and GCT in cancer group were significantly longer [SMV:(11.2±1.3) mm vs. (9.5±1.7) mm, t=6.04, P<0.001; GCT:(5.5±0.9) mm vs. (3.5±1.0) mm, t=11.51, P<0.001]. However, there were no statistically significant differences in diameters of SMV and GCT among hepatic metastasis, lymph node metastasis and no metastasis cancer groups (all P>0.05). The ROC curve analysis showed that the area under the curve of SMV diameter was 0.777, and the optimal cut-off point was 10.5 mm in the diagnosis of cecum-ascending colon cancer, with the sensitivity and specificity of 95.0%(57/60) and 46.7%(28/60) respectively. The area under the curve of GCT diameter was 0.923, and the optimal cut-off point was 4.5 mm in the diagnosis of cecum-ascending colon cancer, with sensitivity and specificity of 88.3%(53/60) and 85.0%(51/60) respectively.

CONCLUSIONThe dilation of the SMV and GCT may be used as warning factors for cecum-ascending colon cancer, especially the diameter of GCT.

Adult ; Aged ; Aged, 80 and over ; Cecum ; Colon, Ascending ; pathology ; Colonic Neoplasms ; pathology ; Female ; Humans ; Male ; Mesenteric Veins ; anatomy & histology ; Middle Aged ; Retrospective Studies

Objective To assess the diagnostic value of magnetization transfer MRI (MTI) for bowel inflammation and fibrosis in humans with Crohn disease (CD). Methods From July 2014 through April 2017, 31 patients with a confirmed diagnosis of CD were prospectively recruited from the First Affiliated Hospital of Sun Yat Sen University. They were scheduled for elective surgery due to bowel obstruction and other complications, and underwent preoperative MR enterography (MRE) and MTI within 15 days of surgery. All cases had available intestinal specimens identified on MRE and resected bowel segments for region by region matching. All patients underwent breath hold conventional MRE and MTI examinations, and then the magnetization transfer ratios (MTRs) of pathological bowel segments were measured. Using region by region correlation between MTI and surgical specimen, the bowel segments were resected to stain with HE for evaluating bowel inflammation, Masson for bowel fibrosis, and typeⅠcollagen staining for the deposition of typeⅠcollagen within the bowel walls. The histologic sections from the most severe areas were scored as 0 (normal), 1 (mild), 2 (moderate) and 3 (severe). The correlations between MTR and histologic scores were analyzed by using Spearman rank correlation or partial correlation. The differences in MTR among different grades of bowel fibrosis were analyzed by one way ANOVA. The efficacy of MTR for predicting bowel fibrosis was evaluated by receiver operating characteristic curves analysis. The difference in MTRs between purely inflammatory bowel walls and mixed fibrotic and inflammatory bowel walls was analyzed by Student s t test. Results Sixty two resected bowel specimens from 31 patients including 9 purely inflammatory bowel walls and 53 mixed fibrotic and inflammatory bowel walls were obtained in this study. There were significant differences in MTR among non fibrotic [(21.45 ± 2.65)%], mildly [(30.88 ± 6.14)%], moderately [(35.14 ± 4.31)%] and severely [(35.14 ± 4.31)%] fibrotic walls (F=38.397,P<0.01). MTRs strongly correlated with fibrosis scores (r=0.681, P<0.01). High accuracy of MTRs was shown (curve under area=0.905, P<0.01) for differentiating moderately severely fibrotic from non fibrotic and mildly fibrotic bowel walls. Using MTR of 31.50% as a cutoff value, the sensitivity and specificity were 93.6% and 80.0%, respectively. The MTRs of purely inflammatory bowel walls [(21.45 ± 2.65)%] were significantly higher than that of mixed fibrotic and inflammatory [(36.28±5.21)%] bowel walls (t=-13.052,P<0.01). MTRs correlated with the scores of type Ⅰ collagen (r=0.325, P=0.044) but did not correlate with inflammation scores (r=-0.024, P=0.857). Conclusions MTI enables quantitative evaluation of bowel fibrosis in patients with CD and can be used to differentiate purely inflammatory CD from mixed fibrotic and inflammatory CD.

[Objective]To explore the efficacy of T2* mapping for evaluating inflammatory activity in the patients with Crohn disease(CD).[Methods]A total of 98 CD patients underwent MR enterographywith T2*WI. T2* values were measured by put-ting regions of interest on the thickening bowel wall on T2*mapping. The activity of bowel segment was scored by magnetic resonance index of activity(MaRIA),to analyze the relationship between T2*values with CD activity.[Results]A total of 160 bowel segments were evaluated and includedinactive(MaRIA<7,n=26),mild(7≤MaRIA<11,n=23),and moderately-severe(MaRIA≥11, n = 111)active lesions. The differences in T2* values amongthese three groups were significant(all P < 0.05). T2* values of 160 bowel segments correlatedclosely withMaRIA(r=0.743,P<0.05). High accuracy of T2*values was shown for differentiating inac-tive from active CD(AUC=0.877)anddifferentiating inactive-mild from moderate-severe CD(AUC=0.848). The threshold T2*value of 20 ms allowed differentiation of mild from moderate-severe CD with74.5%sensitivity and 84%specificity.[Conclusions]T2*values, as thequantitative indexof T2*mapping,correlate well with CD activity and showsatisfiedefficacy for diagnosing inflammatoryactivity.

[Objective] To measure the diameter of the superior rectal vein (SRV) & theinferior mesenteric vein (IMV) by CT and analyze their relationship with lymphatic metastasis of rectal carcinoma.And to discuss the feasibility of utilizing SRV to prcdict lymph node metastasis of rectal cancer.[Methods] The CT imaging and pathological data of 105 rectal carcinoma patients were analyzed retrospectively.We measured and compared the diameter of every patient's SRV & IMV by CT in the presence and absence of microvascular tumor thrombus,signet ring cell,lymph node metastasis and distant metastasis.The accuracy of predicting lymph node metastasis for rectal carcinoma by the diameter of SRV were evaluated by ROC curve.[Results] There were statistical differences in the diameters of SRV and IMV between rectal cancer group with lymph node metastasis (D =4.34 mm,D =5.00 mm) and without (D =3.56 mm,D =4.81 mm;P ＜ 0.001,P =0.023).The differences were significant in the diameter of SRV between rectal cancer group with microvascular tumor thrombus or signet ring cell and without (P =0.019,P =0.044).However,the diameter of IMV showed no statistical difference between rectal cancer group with microvascular tumor thrombus or signet ring cell and without (P =0.605,P =0.663).And there was no statistical difference in the diameter of SRV or IMV between rectal cancer patients with distant metastasis and without (P ＞ 0.05).Regarding 3.75 mm as the cut-off value for the diameter of SRV to predict lymph node metastasis for rectal cancer patients,the sensitivity was 90.9％ and the specificity was 82.0％.Regarding 4.65 mm as the cut-off value for the diameter of IMV to predict lymph node metastasis for rectal cancer patients,the sensitivity was 87.3％ and the specificity was 38％.[Conclusions] It is completely feasible to utilize the diameter of SRV measured by CT to predict lymph node metastasis of rectal carcinoma with high sensitivity,accuracy,and relatively high specificity.