Objective:To review the application of pediatric magnetic resonance enterography (MRE) at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from 2012 to 2023, and to provide referenceable data for MRE use in complex pediatric clinical scenarios.Methods:This study was a cross-sectional study. The clinical and imaging data from children aged≤18 years who underwent MRE at Tongji Hospital between December 2012 and December 2023 were retrospectively analyzed. Out of 186 children who intended to receive the MRE examination, 12 failed, remainder 174 participants (mean age 14±4 years, range 1 month to 18 years) were included. Participants were categorized into an inflammatory bowel disease (IBD) group (118 cases) and a non-IBD group (56 cases), and further divided by age into infants (0-6 years, 8 cases), children (7-12 years, 37 cases), and adolescents (13-18 years, 129 cases). The overall image quality and the intestinal filling quality were scored using a 5-point scale. Statistical analyses included χ2 tests for age distribution, history of intestinal reconstruction surgery, and MRE success rates between IBD and non-IBD groups. Mann-Whitney U test was employed to compare subjective image quality scores between the abovementioned two groups. The Kruskal-Wallis test was used to detect the differences among the three age groups. Results:The success rate of MRE significantly increased with age: 66.7% (8/12) in infants, 88.1% (37/42) in children, and 97.7% (129/132) in adolescents ( χ2=15.39, P<0.001). A statistically significant difference in age distribution was observed between the IBD and non-IBD groups ( χ2=17.94, P<0.001). The proportion of infants in the non-IBD group was 14.3% (8/56), which was higher than that of the IBD group. The majority of the IBD group were adolescents, accounting for 78.8% (93/118). There was a statistically significant difference in the intestinal reconstruction surgery history ( χ2=2.83, P=0.005). The non-IBD group had a higher incidence of intestinal reconstructive surgery (21.4%, 12/56), compared to the IBD group (6.8%, 8/118). MRE intestinal filling quality or overall image quality scores between the IBD and non-IBD groups or among different age sub-groups were not statistically significant ( P>0.05). Conclusion:Juvenilization of non-IBD children and intestinal reconstructive surgery history could make the inspection more complex. High-quality imaging can still be achieved by adhering to technical specifications.

Objective: To investigate the value of combined chemical exchange saturation transfer (CEST) and conventional magnetizationtransfer imaging (MT) in detecting metabolic and structural changes of renal fibrosis in rats with unilateral ureteral obstruction(UUO) at 3T MRI. Materials and Methods: Thirty-five Sprague-Dawley rats underwent UUO surgery (n = 25) or sham surgery (n = 10). Theobstructed and contralateral kidneys were evaluated on days 1, 3, 5, and 7 after surgery. After CEST and MT examinations,18F-labeled fluoro-2-deoxyglucose positron emission tomography was performed to quantify glucose metabolism. Fibrosis wasmeasured by histology and western blots. Correlations were compared between asymmetrical magnetization transfer ratio at1.2 ppm (MTRasym(1.2ppm)) derived from CEST and maximum standard uptake value (SUVmax) and between magnetization transferratio (MTR) derived from MT and alpha-smooth muscle actin (α-SMA). Results: On days 3 and 7, MTRasym(1.2ppm) and MTR of UUO renal cortex and medulla were significantly different from those ofcontralateral kidneys (p < 0.05). On day 7, MTRasym(1.2ppm) and MTR of UUO renal cortex and medulla were significantly differentfrom those of sham-operated kidneys (p < 0.05). The MTRasym(1.2ppm) of UUO renal medulla was fairly negatively correlated withSUVmax (r = -0.350, p = 0.021), whereas MTR of UUO renal medulla was strongly negatively correlated with α-SMA (r = -0.744, p <0.001). Conclusion CEST and MT could provide metabolic and structural information for comprehensive assessment of renal fibrosisin UUO rats in 3T MRI and may aid in clinical monitoring of renal fibrosis in patients with chronic kidney disease.

Objective To investigate the feasibility of the CT texture analysis (CTTA)in differentiating autoimmune pancreatitis (AIP)from pancreatic ductal adenocarcinoma (PDAC).Methods 25 patients with AIP and 31 patients with PDAC who confirmed by pathological or clinical underwent pretreatment three-phase contrast-enhanced CT were enrolled.Histogram parameters (mean CT values,median CT values,25 th,75 th percentile CT values,skewness,kurtosis,entropy and uniformity)were derived from CT images through texture analysis.The differences of histogram parameters between AIP and PDAC groups were compared.ROC and AUC were used to evaluate the diagnostic efficacy of histogram parameters in differentiating AIP from PDAC.Results The values for mean CT values,median CT values,25 th,75 th percentile CT values and uniformity of AIP were significantly higher than those of PDAC group,while the values for entropy of AIP were significantly lower than those of PDAC group in arterial phase,portal phase,and delay phases (all P＜0.05). There were no significant differences in kurtosis and skewness between AIP and PDAC groups (all P＞0.05).The uniformity in portal phase achieved the optimal diagnostic accuracy in differentiating AIP from PDAC (AUC＝0.973 ),the cutoff value was 0.797,the corresponding sensitivity and specificity were 92% and 9 6.8%,respectively.Conclusion CTTA can be used as a quantitative analysis method for differential diagnosis between AIP and PDAC,providing a reference for clinicians to select therapeutic schedules.

Objective To explore the utility of ADC histogram analysisin differentiation of clear cell renal cell carcinoma(ccRCC)and non-clear cell renal cell carcinoma(non-ccRCC)with r-Fov DWI. Methods Sixty-six renal tumors(46 patients with 47 ccRCCs and 18 patients with 19 non-ccRCCs)in 64 patients, who underwent preoperative routine renal MRI sequences and r-FOV DWI, were retrospectively evaluated. The whole-lesion ADC values derived from histogram anlysis(including ADC mean, ADC median, ADC_5th, ADC_25th, ADC_75th, ADC_95th, skew and kurtosis)were measured for each patient. All parameters between ccRCC and non-ccRCC were compared by using the Student's t test or Mann-Whitney U test. ROC analysis was used to assess the diagnostic performance of ADC histogram in distinguishing the two groups. Results The postive skewness of ADC histograms were mostly seen in the non-ccRCC group, while the negtative skewness were present in the majority of ccRCCs. The skewness was significantly higher in non-ccRCCs than those of ccRCCs(P<0.05). Mean ADC, median ADC, 5th percentile ADC, 25th percentile ADC, 75th percentile ADC and 95th percentile ADC(all P<0.05)were significantly lower in non-ccRCC . There was no significant difference of Kurtosis between two groups(P>0.05). 75th percentile ADC achieved the highest AUC(0.987)in differentiating ccRCC and non-ccRCC, whena cutoff value was 1.81× 10-3 mm2/s. The sensitivity and specificity were 100.0％and 94.7％. Conclusion ADC histograms of r-FOV DWI may be helpful to differentiate ccRCC from non-ccRCC, and the diagnostic accuracy of 75th percentile ADC is highest.

Objective MRI manifestations of infiltrative renal pelvis carcinoma were analyzed and evaluated,to improve its diagnostic accuracy. Methods MRI features of 21 cases of infiltrative renal pelvis carcinoma confirmed pathologically were analyzed retrospectively.All patients underwent plain MRI scan and DWI examination,3 cases underwent PWI examination.Results The center of lesions for all cases were located in the renal collection system,with no change of the renal contour.Most lesions were presented as low signal intensity on T1 WI and slightly low signal intensity on T2 WI,and heterogeneous signal intensity were showed on T1 WI and T2 WI in 5 cases.All lesions were presented as high signal intensity on DWI.After contrast enhancement,mild and moderate enhanced lesions were demonstrated in 3 cases.Renal arteries were wrapped by renal pelvis carcinoma on renal AMRA in 3 cases.4 patients were accompanied with venous tumor thrombus and 1 1 patients with retroperitoneal lymph node metastasis.Adrenal gland metastases were showed in 3 cases.1 case was accompanied with ureter urothelial carcinoma,and 2 cases with bladder carcinomas.Conclusion MRI has a multi-parameter imaging capability and high resolution of soft tissue,and can clearly show the boundary of lesions and surroundings.MRI plays an important role in the diagnosis and differential diagnosis of infiltrative renal pelvis carcinoma.

Objective To investigate anatomic feature of variant right hepatic artery originating from the gastroduodenal artery.Methods We studied the anatomy of hepatic artery in 70 patients by 64-slice CT scans.If the right hepatic artery originated from the gastroduodenal artery,its relation to duodenum,common bile duct and portal vein was further investigated.Results Normal hepatic artery was found in 40 patients (57.1％).Variant hepatic artery can't be categorized to classic types in 8 patients (11.4％),among them 6 patients (8.6％) were with replaced (5 patients) or accessory (one patient) right hepatic artery arising from gastroduodenal artery.With the distance between original point of the right hepatic artery and that of the gastroduodenal artery growing further anatomic course of the variant right hepatic artery is more similar to that of the right hepatic artery originating from the superior mesenteric artery.Conclusions The variation of right hepatic artery originating from the gastroduodenal artery was not uncommon.This specific variant hepatic artery can exert impact on biliary blood supply,avoiding injury decreases the incidence of serious biliary complications in general surgery.

Objective To investigate the features of computed tomography (CT) and magnetic resonance imaging (MRI) on pancreatic neuroendocrine tumors (pNENs).Methods The retrospective and descriptive study was adopted.The clinicopathological data of 33 patients with pNENs who were admitted to the Tongji Hospital of Tongji Medical School of Huazhong University of Science and Technology between May 2012 and February 2016 were collected.All the patients underwent plain and enhanced scans of CT and MRI.Observation indicators:(1) overall imaging findings and pathological results of pNENs,(2) imaging findings of functional pNENs,(3) imaging findings of non-functional pNENs.Main analysis indicators included tumor diameter,location,boundary,density,cystic degeneration,enhancement,signal,calcification,with or without pancreaticobiliary duct dilation,with or without surrounding tissues invasion,lymph node and distant organ metastases.Results (1) Overall imaging findings and pathological results of pNENs:of 33 patinets with pNENs,24 underwent CT examination,3 underwent MRI examination and 6 underwent CT and MRI examinations.Tumors of 33 patients were solitary with a diameter of 0.6-16.0 cm.Ten,1,13 and 9 tumors were respectively located at the head of pancreas,uncinate process of pancreas,body of pancreas and tail of pancreas.Thirty-three patients were diagnosed as pNENs by pathological examination,including 20 with functional pNENs (insulinoma) and 13 with non-functional pNENs,and G1,G2 and G3 were respectively detected in 24,7 and 2 patients.The coincidence rate between preoperative CT or MRI examination and pathological examination was 90.9％ (30/33).One,1 and 1 patients were misdiagnosed as pancreatic cancer,enlargement of peripancreatic lymph nodes and duodenal gastrointestinal stromal tumor,respectively.(2) Imaging findings of functional pNENs:tumor diameter of 20 patients with functional pNENs was 0.6-3.0 cm with an average diameter of 1.5 cm.Fòur,10 and 6 tumors were respectively located at the head of pancreas,body of pancreas and tail of pancreas.Of 20 patients with functional pNENs,tumors of 19 patients showed clear boundary and 1 showed unclear boundary,and tumors of 18 patients had uniform density and 2 had uneven density with cystic degeneration,without the occurrence of calcification.Of 20 patients undergoing dynamic enhanced scans,tumors of 19 patients demonstrated obvious enhancement in arterial phase and slightly obvious enhancement or were equal to normal pancreatic tissues in portal vein phase and lag phase,and tumor of 1 patient demonstrated slight enhancement in arterial phase and was equal to or less than normal pancreatic tissues in portal vein phase and lag phase.Tumors in 3 patients undergoing MRI scans were manifested as hypointensity on T1-weighted imaging (T1WI),hyperintensity on T2WI and hyperintensity on DWI (b =1 000 s/m2),with clear imaging.Of 20 patients,1 was accompanied with atrophy of pancreatic tissues at distal tumor,pancreatic duct dilatation,multiple retention cyst and enlargement of lymph nodes around the hepatic artery.(3) Imaging findings of non-functional pNENs:tumor diameter of 13 patients with non-functional pNENs was 1.5-16.0 cm with an average diameter of 5.0 cm.Six,1,3 and 3 tumors were respectively located at the head of pancreas,uncinate process of pancreas,body of pancreas and tail of pancreas.Of 13 patients with non-functional pNENs,tumors of 11 patients showed clear boundary and 2 showed unclear boundary,tumors of 3 patients had uniform density and 10 had uneven density with cystic degeneration,and tumors of 2 patients had calcification.Of 13 patients undergoing dynamic enhanced scans,tumors of 12 patients demonstrated obvious enhancement in arterial phase,continuous enhancement in portal vein phase and lag phase and less obvious enhancement at cystic degeneration area,with marked enlargement of supplying arteries and draining veins in partial tumors.Tumor of 1 patient demonstrated slight enhancement,and its enhancement was slightly less than normal pancreatic tissues in arterial phase,portal vein phase and lag phase,with unclear boundary.Results of MRI scans in 6 patients showed that tumors of 4 patients were manifested as hypointensity on T1WI,slight hyperintensity or mixed signal on T2WI and hyperintensity on DWI (b =1 000 s/m2),and tumors of 2 patients were manifested as hypointensity on T1WI,hypointensity on T2WI and hyperintensity on DWI (b =800 s/m2).Of 13 patients with non-functional pNENs,4 had pancreaticobiliary duct dilation and 7 had local tissues invasion or distant organ metastasis (4 with liver metastasis,1 with peripanereatic lymph node metastasis,1 with liver and peripancreatic lymph node metastases and 1 with liver metastasis combined with splenic venous and arterial invasion),including 1 in G1,4 in G2 and 2 in G3.Of 5 patients with tumor diameter ＞ 5.0 cm,4 were complicated with liver or lymph node metastases.Conclusions CT and MRI features of pNENs have a certain characteristics.For functional pNENs,benign and solid tumor is common,with clear boundary and smaller diameter.For non-functional pNENs,tumor size is bigger and cystic necrosis occurs within the tumor,with various enhancements.

Objective To validate the feasibility and accuracy of iterative decomposition of water and fat with asymmetry and least squares estimation-quantitative fat imaging (IDEAL-IQ) in fat quantification using fat-water model. Methods A homogeneous fat-water mixture model consisting of various known fat-fractions were described, and the fat fraction was 0.00, 0.01, 0.02, 0.04, 0.06, 0.08, 0.10, 0.14, 0.18, 0.22, 0.26, 0.30 g/ml respectively. A water-vaseline separated model was also described. IDEAL-IQ was performed. Thin slices were acquired for fat-water mixture model and repeated 3 days later. Nineteen slices of 14 mm-thick parallel to the water-vaseline boundary in 1 mm steps from vaseline to water
were acquired. The fat-fractions in 11 slices of fat-water mixture model were measured on FatFrac images. Accuracy was assessed through single sample t test or Kolmogorov-Sirmov test. Measured fat-fractions of the same known fat-fraction were assessed through independent samples t test between two scan times. Linear regression was used to assess the relationship between known fat-fractions and measured fat-fractions. Slices containing the water-vaseline boundary were measured with ROI in the middle of the FatFrac images. The relationship between measured fat-fractions and locations of scanning was exploded using curve fitting. Results (1) Fat-water mixture model: no significant difference(P>0.05) was found between measured fat-fractions and known fat-fractions when it was 0.00, 0.02, 0.06 and 0.08 g/ml with the measured fat-fractions 0.60%, (2.30 ± 0.60)%, (5.76 ± 1.40)%, (7.62 ± 1.40)% respectively for the first time. No significant difference(P>0.05) was found between measured fat-fractions and known fat-fractions when it was 0.00, 0.02, 0.10 g/ml with the measured fat-fractions 0.04%, (2.32 ± 0.60)%, (9.41 ± 1.00)%respectively for the second time. Measured fat-fraction was inlinear relation with known fat-fraction:Y=0.898X+0.224, r2=0.993, P<0.01, F=36 129.548.(2) Water-vaseline separated model: measured fat-fraction increased as scanning location changed, Y=0.045X2-0.499X-4.474, r2=0.978, P<0.05, F=350.623.Conclusions IDEAL-IQ can be used to quantify fat content with good repeatability and can accurately assess the actual fat content from the linearrelationship.

Intestinal non-neoplastic diseases, including inflammation, bleeding and trauma, are common and frequently-occurring diseases. With the development of diagnosis and the change of disease spectrum, more and more clinical attentions are paid to autoimmune intestinal colitis, Crohn's disease, irritable bowel syndrome, ischemic bowel disease, intestinal polyps and other non-neoplastic diseases. Radiological modalities and characteristics of non-neoplastic bowel diseases are summarized and evaluated in this article. We hope to provide useful information for clinicians to select radiologic methods correctly.
Colitis ; Crohn Disease ; Humans

Objective To determine whether hybrid three dimensional diffusion tensor imaging (3D DTI) contributes incremental value to standard T2WI technique for assessing neurovascular bundles (NVB) around the prostate. Methods This retrospective institutional review board-approved study included 69 consecutive patients with prostate tumor who underwent MRI including conventional T2WI and 3D DTI . DTI data were postprocessed and hybrid 3D DTI and axial T2W images were obtained. Three radiologists with one, five and thirteen years of experience in reading prostate MRI and one urologist with three years of surgical experience in urology who were blinded to patient data independently recorded their levels of preference on a five-point scale of the NVBs around the prostate on the basis of T2WI alone and hybrid 3D DTI and T2WI, respectively. The differences of scores of T2WI and hybrid 3D DTI and T2WI of the four doctors were compared by using nonparametric Wilcoxon rank. Results The average scores of hybrid 3D DTI to T2WI and alone T2WI to assess NVBs for 3 radiologists and one urologist were 4.4±0.6, 4.3±0.8, 4.2± 0.6, 4.9±0.3 and 2.9±0.8, 3.0±1.1, 1.6±0.7, 3.8±0.5, respectively. The hybird 3D DTI to T2WI improved the discrimination abilities of NVBs around the prostate for 3 radiologists and one urologist (Z values were-12.791,-9.737,-14.538,-14.901, P<0.01 respectively).The added value of hybrid DTI to T2WI for urologist is the highest, and experienced radiologist is the smallest. Conclusion The hybrid 3D DTI
contributes significant incremental value to the standard T2WI technique for assessing NVB around the prostate.