Objective To evaluate the digital tomosynthesis in the diagnosis of occult bone fracture. Methods Both DR and DTS were performed in 135 cases with traumatic-induced pain. All the cases were suspected of bone fractures but with no abnormal findings in DR images. Two radiologists reviewed all the images and diagnosed in consensus. All cases were followed up and the imaging diagnoses were reviewed. Results Bone fractures or joint dislocations of 61 cases were shown in DTS images but not in DR images, including atlanto-axial fracture and subluxation in 7 cases, articular fracture of limbs in 20 cases, bone fractures of wrist, hand and foot in 11 cases, fractures of cervical, thoracic and lumbar vertebra in 7 cases, fracture of sacrococcyx in 8 cases, fracture of nasal bone in 4 cases, fractures of Sternum ,rib ,orbit and mandible in 1 case. Thirty-four cases with bone fractures were determined by using DTS in suspected cases and 17 cases were denied. Both DR and DTS images showed normal findings in 23 cases. Imaging diagnoses of all cases were consistent with the results of follow up. Conclusion DTS can depict bone fractures especially in the deep and complex bony structures, which may improve the diagnostic accuracy of bone fracture.

[Objective] To analyze the image findings of MR enterography (MRE) and diffusion weighted imaging (DWI) in Crohn disease (CD) and to discuss the diagnostic value of MRI for evaluating the activity of CD.[Methods] 26 patients proved by clinical,imaging and pathological data were enrolled in this study.The intra-/extra-intestinal image features of CD were retrospectively analyzed,and the intestinal lesions were evaluated by MRE+DWI scoring system.The differences in image features of active and inactive CD were compared.[Results] 26 bowel segments were evaluated and included active (n =20) and inactive CD (n =6).The intestinal performance of CD included wall thickening,T2WI hyperintensity and hyperenhancement.The pathological changes of active CD were more serious when comparing with that of inactive CD.DWI showed hyperintensity in the affected bowel wall.ADC of active C D [(0.9 ± 0.2) × 10-3 mm2/s] was significantly lower than that of inactive CD [(1.5 ± 0.4)× 10-3 mm2/s] (P ＜ 0.001).Extra-enteric performance of active CD included comb sign,lymphadenectasis of mesentery,mesenteric exudation,fistula and abdominal abscess.[Conclusion] MRE combined with DWI can accurately assess CD activity and diagnose extra-enteric complications.

Objective To discover radioresistance-associated proteins by performing comparative proteomic analysis on nasopharyngeal carcinoma cell lines.Methods The total proteins were extracted from radioresistant human nasopharyngeal carcinoma cell line CNE-2R and its parental cell line CNE-2,respectively.These proteins were separated by high quality two-dimensional polyacrylamide gel electrophoresis (2-DE) and then the 2-DE profiles were screened for differentially expressed protein spots by the Image Master 5.0 software.Those spots were identified by a matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry.Results 32 significantly differentially expressed protein spots were screened in two different radiosensitivity cell lines and 11 proteins were identified by tandem mass spectrometry,among which 3 proteins were up-regulated in radioresistant human nasopharyngcal carcinoma cell line CNE-2R and the other 8 proteins were down-regulated.Conclusions The differentially expressed proteins of nasopharyegeal carcinoma cells with different radiosensitivity were mainly involved in apoptosis regulation,DNA damage and repair,cell cycle regulation,RNA transcription,cell signaling,cytoskeleton formation and radiation stress responses.

Objective To discover radioresistance associated molecular biomarkers and its mechanism in nasopharyngeal carcinoma by protein-protein interaction network analysis.Methods Whole genome expression microarray was applied to screen out differentially expressed genes in two cell lines CNE- 2R and CNE-2 with different radiosensitivity.Four differentially expressed genes were randomly selected for further verification by the semi-quantitative RT-PCR analysis with self-designed primers. The common differentially expressed genes from two experiments were analyzed with the SNOW online database in order to find out the central node related to the biomarkers of nasopharyngeal carcinoma radioresistance. The expression of STAT1 in CNE-2R and CNE-2 cells was measured by Western blot.Results Compared with CNE-2 cells,374 genes in CNE-2R cells were differentially expressed while 197 genes showed significant differences.Four randomly selected differentially expressed genes were verified by RT-PCR and had same change trend in consistent with the results of chip assay. Analysis with the SNOW database demonstrated that those 197 genes could form a complicated interaction network where STAT1 and JUN might be two key nodes.Indeed,the STAT1-α expression in CNE-2R was higher than that in CNE-2 (t =4.96,P ＜ 0.05).Conclusions The key nodes of STAT1 and JUN may be the molecular biomarkers leading to radioresistance in nasopharyngeal carcinoma,and STAT1-α might have close relationship with radioresistance.

[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.

Yolk sac tumor (YST) is a rare germ cell neoplasm of childhood that usually arises from the testis or ovary. The rare cases of YST in various extragonadal locations have been reported, but the primary intrarenal YST is even more uncommon. Here, we report a case of a primary intrarenal YST with tumor thrombus of the inferior vena cava and left renal vein in a 2-year-old boy, with an emphasis on the CT features. To our knowledge, this is the first reported case of an intrarenal YST with intravascular involvement.
Child, Preschool ; Humans ; Male ; Neoplasms, Germ Cell and Embryonal/*diagnosis/pathology/ultrasonography ; Renal Veins/pathology/*radiography ; Thrombosis/pathology/radiography ; *Tomography, X-Ray Computed ; Vena Cava, Inferior/pathology/*radiography

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.

Objective:To explore the diagnostic efficacy of nomogram based on multi-parameter MRI for assessment of bowel fibrosis in patients with Crohn disease（CD).Methods:The clinical and imaging data of CD patients diagnosed by surgical histopathology in the First Affiliated Hospital of Sun Yat-sen University from June 2015 to March 2018 were prospectively collected. All the patients underwent conventional MRI and diffusion kurtosis imaging（DKI) within 2 weeks before surgery. Patients who underwent surgery between June 2015 and September 2017 were included in the model building group, and those who underwent surgery between October 2017 and March 2018 were included in the model validation group. We measured the apparent diffusion coefficient（ADC) from monoexponential model of diffusion-weighted imaging（DWI), apparent diffusional kurtosis（K app), and apparent diffusion for non-Gaussian distribution（D app) from non-Gaussian DKI model, and observed T 2WI signal intensity and enhancement pattern of the same segment. One to three intestinal specimens per patient were stained with Masson′s trichrome for the histological grading of fibrosis. Correlations between qualitative/quantitative MRI indexes and histological grades were evaluated using the Spearman rank test. Multivariate logistic regression analysis was performed to identify independent factors to be included into the nomogram for predicting the degree of bowel fibrosis and its diagnostic performance was assessed by internal and external validation. Results:A total of 40 CD patients were included, including 31 in the model construction group and 9 in the model verification group. A total of 81 intestinal specimens from 31 patients were graded as none-to-mild bowel fibrosis（ n=32) and moderate-to-severe bowel fibrosis（ n=49) according to a scoring system of fibrosis. In the training cohort, the K app value of moderate-to-severely fibrotic bowel walls was significantly higher than that of none-to-mildly fibrotic bowel walls, and the D appand ADC values of moderate-to-severely fibrotic bowel walls were significantly lower than those of none-to-mildly fibrotic bowel walls（ Z=-5.999, -4.521 and -3.893; P<0.001). There was no significant difference in T 2WI signal intensity or enhancement pattern between these two groups（χ2=1.571 and 0.103; P>0.05). Moderate and mild correlations of histological fibrosis grades with K appand D app( r=0.721 and -0.483; P<0.001), and a mild correlation with ADC（ r=-0.445, P<0.001) were found. Independent factors derived from multivariate logistic regression analysis to predict the degree of bowel fibrosis were K app and D app. Internal and external validation revealed good performance of the nomogram with concordance index of 0.901（95% confidence interval, 0.824-0.978) and 1.000, respectively, for differentiating none-to-mild from moderate-to-severe fibrosis. Conclusion:The DKI-based nomogram can be used to evaluate the bowel fibrosis in CD patients and provides a visual and simple prediction method for clinic.

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.

OBJECTIVETo explore the value of comprehensive application of CT and PET/CT in differential diagnosing mucinous and non-mucinous colorectal adenocarcinoma.

METHODSCT and PET/CT image data of 37 patients with mucinous adenocarcinoma and 50 patients with non-mucinous adenocarcinoma confirmed by pathology in our hospital from January 2010 to December 2012 were analyzed retrospectively. Differences of image were compared between two methods.

RESULTSOn CT, lesion density of pre-contrast, pro-contrast phase and enhancement degree were significantly lower in mucinous adenocarcinoma than those in non-mucinous adenocarcinoma(all P<0.01). Enhancement degree of hypointense area, hypointense area proportion of total lesion, and lymphatic or distant metastasis ratio were significantly higher in mucinous adenocarcinoma than those in non-mucinous adenocarcinoma(all P<0.05). On PET/CT, maximal SUV value of mucinous adenocarcinoma was significantly lower as compared to non-mucinous adenocarcinoma[(8.64±4.34) Bq/L vs. (12.38±5.96) Bq/L, P=0.015].

CONCLUSIONSCT combined with PET/CT provides better valuable information in differential diagnosing between mucinous and non-mucinous colorectal adenocarcinoma and clinical practice.

Adenocarcinoma ; diagnostic imaging ; Adenocarcinoma, Mucinous ; diagnostic imaging ; Colorectal Neoplasms ; diagnostic imaging ; Humans ; Multimodal Imaging ; Positron-Emission Tomography ; Retrospective Studies ; Tomography, X-Ray Computed