Objective To study the helical CT dual-phase feature of peripheral enhancement in small hepatocellular carcinoma (SHCC) and to evaluate its correlation with the histopathology. Methods The helical CT dual-phase feature of peripheral enhancement in SHCC was analyzed in 17 cases with 18 lesions, all the lesions were confirmed by operation and histopathology. Results In 17 lesions, peripheral enhancement ring of the lesions wasn′t intact, the thickness of peripheral enhancement ring wasn′t uniform, and small nodular enhancement was found inside the peripheral enhancement ring in hepatic arterial phase (HAP). In 1 lesion, the peripheral enhancement ring of the lesion was intact and the thickness of peripheral enhancement ring was uniform in HAP. The density of the peripheral enhancement ring and the small nodular enhancement decreased to hypodense or isodense than the normal liver parenchyma in portal venous phase. Pathologic pattern: 16 lesions were trabecular type and 2 lesions were scirrhous type. The differentiation of the tumor cell was grade I in 2 lesions, grade Ⅱ in 14 lesions, grade Ⅲ in 1 lesion, and grade Ⅳ in 1 lesion, respectively. In 12 lesions, the vessels were richer in the lesion border than that in the lesion center. In 6 lesions, the vessels were less rich in both center and border. In 3 lesions, the pseudo-capsule was showed in the border of the lesion. In 10 lesions, the flecks of necrosis were demonstrated in the border and/or center of the lesion. Conclusion The helical CT dual-phase feature of peripheral enhancement in SHCC is characteristic, and SHCC might be distinguished from other hepatic diseases with peripheral enhancement.

Objective To study the helical CT dual-phase enhancement manifestation of the hypodense small hepatocellular carcinoma, and to evaluate its correlation with the histopathology. Methods The CT signs and its histopathologic changes were analyzed in 25 cases with 27 hypodense lesions in helical CT dual-phase enhancement. All the lesions were confirmed as small hepatocellular carcinoma by operation and histopathology. Results (1) On unenhanced scan, 16 lesions were with obscure borders and 11 lesions were with well-delineated borders. On enhanced scan, only 7 lesions were with obscure borders and the other 20 lesions were with well-delineated borders, and their contours were slightly irregular. (2) On unenhanced scan, 18 lesions showed homogeneous hypodensity and 9 lesions showed heterogeneous hypodensity. On enhanced scan, only 6 lesions showed homogeneous hypodensity and the other 21 lesions showed heterogeneous hypodensity with multiple flecks of more hypodense areas. Conclusion The helical CT dual-phase enhancement characteristic manifestations of hypodense small hepatocellular carcinoma were as follows: the border of the lesion was obscure on unenhanced scan, however the border of the lesion became well-delineated and slightly irregular, and there were multiple flecks of more hypodense areas in the lesions after enhancement. This might be an important character in distinguishing hypodense small hepatocellular carcinoma from other hypodense diseases in the liver.

Objective To study the helical CT signs of the hepatocellular carcinoma (HCC) after percutaneous microwave coagulation therapy (PMCT) and to evaluate the correlation between the helical CT signs and the therapeutic effect of HCC. Methods The helical CT signs were analyzed in 22 cases with 26 lesions of the hepatocellular carcinoma that were treated with PMCT under ultrasonic guidance. Results In 21 lesions, no enhancement was detected in the lesion border or inside the lesion at hepatic arterial phase (HAP) and portal venous phase (PVP). In 7 lesions, the slight or marked patchy enhancement was revealed in the surrounding liver of the lesions in HAP. In 5 lesions, nodular enhancement was found in the lesion border or inside the lesion in HAP. Conclusion The dual-phase helical CT might be accurate in judging the therapeutic effect of HCC after PMCT. If no enhancement was showed in the lesions in the dual-phase helical CT, it indicated that no tumor survived. If slight or marked patchy pattern enhancement was revealed in the surrounding liver of the lesions in HAP, it was a normal reaction after PMCT. If nodular enhancement was found in the lesion border or inside the lesion in HAP, it indicated that the tumor partially survived.

Objective To study the value of dual-phase enhanced multi-slice computed tomography (MSCT)scan in combination with the reconstruction technique for distinguishing gallbladder adenomyomatosis (GBA)from gallbladder cancer.Methods We ret-rospectively reviewed the CT features (including dual-phase and reconstructed images)of 36 patients with GBA (Group A,1 6 pa-tients)or gallbladder cancer (Group B,20 patients)proved by pathology.Fisher exact test was used to compare the CT findings be-tween the two groups.Results The occurrence rates of RAS,gallbladder wall smoothing,clear gallbladder border,uniform en-hancement of serous layer and thickening of the gallbladder wall were statistically significantly different between Group A and B. When using the Rokitansky-Aschoff sinuses as a parameter for the differential diagnosis of the two groups,the diagnostic accuracy reached to 92.85%.Conclusion Dual-phase enhanced MSCT scan in combination with the reconstruction technique is a valuable ima-ging technique for distinguishing GBA from gallbladder cancer.

Objective To investigate the diognostic value of multi-sllce helical CT(MSCT) in spinal tuber-culosis, and making a further understanding of this disease. Methods The MSCT and post-processing films manifes-tations of 23 spinal tuberculosis proved by operation and pathology were reviewed retrospectively. Results MSCT could show the bone destructions location, range, relationships with neighbor tissues, osseous vertebral narrowing and para-vertebral abscess,etc. MPR, CPR, SSD and VR could more completely and stereoscopically show these character-istics of spinal tuberculosis. Conclusion MSCT post-processing techniques could make up for the lack of axial CT scan. It has high value in elevating the diagnosis accuracy of spinal tuberculosis.

Objective To assess the characterization and usefulness of contrast enhanced ultrasound (CEUS)to diagnose solid focal lesions of pancreas(s-FLPs)in comparison to contrast enhanced computed tomography(CECT).Methods Forty-nine s-FLPs with final diagnosis were studied with low mechanical index CEUS and CECT.The enhanced patterns and diagnostic capability of CEUS were analyzed,and these results were compared with those from CECT.Results ①In CEUS,the perfusion of capillary could be detected in vascular phase.②The concordance of dual-phases enhanced patterns between CEUS and CECT was 73.5%(36/49).The concordance of enhanced level between early parenchymatous perfusion phase in CEUS and pancreatic phase in CECT could achieve 87.8%(43/49).Hypo/hypo enhancement was the most common enhanced pattern of pancreatic carcinoma in CEUS and CECT.③There was no statistical significance between CEUS and CECT in the differential diagnostic.Conclusions The concordance of enhanted patterns between CEUS and CECT is satisfactory.CEUS is similar to CECT in the differential diagnosis of s-FLPs.CEUS would become an important non-invasive diagnostic method for s-FLPs.

Objective To evaluate the accuracy and utility of percutaneous ultrasonic cholangiography in Bismuth staging of hilar cholangiocarcinoma. Methods Thirty patients who underwent surgery and obtained pathologic diagnosis of hilar cholangiocarcincoma were perspectively ruled in this study. All patients with hilar obstruction underwent baseline ultrasound (BUS), percutaneous ultrasonic cholangiography (PUSC) and percutaneous transhepatic cholangiography(PTC) respectively. Taking operative findings as reference standard,the accuracy of the three imaging modalities in staging of hilar cholangiocarcinoma was compared. Results Among 30 patients, the accuracy of classification among BUS, PUSC and PTC was 23.3 % (7/30), 73.3 % ( 22/30 ), 73.3 % (22/30), respectively. There was statistically significant difference between BUS and PUSC, but the difference between PUSC and PTC was not statistically significant.Conclusions As a new technique for cholangiography, PUSC expands the application of ultrasound in evaluating hilar cholangiocarcinoma and is comparable to PTC in classifying hilar cholangiocarcinoma by Bismuth classification.

ObjectiveTo evaluate the diagnostic value of CT in adults with midgut malrotation.MethodsThe CT and clinical findings of 13 cases confirmed by surgery were analyzed retrospectively.ResultsCT found “whirl sign” in 9 cases,“transposition sign” in 5 cases,and the superior mesenteric vein located in right lower abdomen in 4 cases.At the same time,duodenum and upper jejunum located in right upper abdomen.Conclusion“Whirl sign” and “transposition sign” were the typical CT findings of midgut malrotation in adults.Ectopic superior mesenteric vein highly indicated slight midgut malrotation in adults.

Objective To investigate the CT diagnostic value of small bowel wall thickness and density in differentiating simple small bowel obstruction (SI) from strangulative small bowel obstruction (ST).Methods Fifty-three cases with thickened small bowel wall (thickness ＞ 3 mm) confirmed on CT scan were reviewed,including 27 cases of SI and 26 cases of ST,in conjunction with their proven intraoperational,pathological and clinical findings.Of the 53 cases,35 cases also underwent postcontrast CT scan.CT manifestations of relationships between thickened small bowel wall and its density were classified as normal,higher or lower density in tunica mucosa of small bowel wall,higher or lower density in full thickness of small bowel wall for exploring the differential diagnostic features between SI and ST on CT scan.Chi-square or Fisher exact test were used to test the proportion difference of CT scan between SI and ST.Results In cases with normal density in tunica mucosa (NDTM) on precontrast CT,there were 21 cases of SI and 6 cases of ST(x2 =15.859,P ＜0.01).However,in cases with NDTM on postcontrast CT,there were 13 cases of SI and 5 cases of ST,and there was no significant difference (x2 =1.377,P ＞ 0.05).Thus,NDTM showed no convincing value in differentiating SI from ST.In cases with lower density in tunica mucosa (LDTM) on precontrast CT,there were 4 cases of SI and 5 cases of ST (P ＞ 0.05).In cases with LDTM on postcontrast CT,there were 4 cases of SI and 4 cases of ST (P ＞ 0.05).Thus,LDTM also showed no value in differentiating SI from ST.The lower density in full thickness of small bowel wall (LDFTS) was revealed in 0 of SI and 10 cases of ST on precontrast CT (P ＜ 0.01),and 0 of SI and 5 cases of ST on postcontrast CT (P ＜ 0.01),indicating that LDFTS showed significant value in differentiating SI from ST.Conclusion Combining the small bowel wall thickness and density,CT manifestations of early bowel wall pathological changes in small bowel obstruction can be acquired,adding some value in the differential diagnosis between SI and ST.

Objective To evaluate the X-ray diagnosis value of intestinal malrotation in adults.Methods The X-ray findings of 16 cases with intestinal malrotation confirmed by surgery were analyzed retrospectively. All of them were taken X-ray plain films, 11 cases were taken alimentary tract barium meal,and 5 cases were taken barium enema. Results Eight cases were found incomplete obstruction of the duodenum, and 2 cases were found low small intestine obstruction on the X-ray plain films. The alimentary tract barium meal showed 4 cases with dilatation and incomplete obstruction of the duodenal bulb to horizontal segment,and the distal end of narrowing intestine appeared as a rat tail,7 cases showed the abnormal duodenal location and shape,called "strip" sign. Four cases were found abnormal duodenojejunal flexure by barium enema examination. Conclusion The alimentary tract barium meal and barium enema examination has great diagnosis value for intestinal malrotation in adults.