Objective To assess value and limitations of non-invasive methods in assessing liver fibrosis．Methods By summarized current situation and advancement of serum fibrotic markers, ultrasound, CT and MRI in assessing liver fibrosis, we investigated their value and limitations. Results In addition to diagnosis, non-invasive methods of assessing liver fibrosis assess severity of liver fibrosis. For liver fibrosis, however, non-invasive methods can not monitor effectively reaction to therapy and progression. Conclusion Non-invasive methods play important roles in diagnosis and assessing severity of liver fibrosis, and reduce the need of liver biopsy.
【Abstract】ObjectiveTo investigate the relationship of magnetic resonance diffusion-weighted imaging (DWI) to histology in the patients of chronic viral hepatitis. MethodsThirty-five patients of chronic viral hepatitis who received liver biopsy and 10 healthy volunteers were included in this study. All of them underwent DWI on a 3.0T MRI device. Apparent diffusion coefficient (ADC) of the liver were measured respectively when b value were set as 100, 400, 600 and 800 s/mm2. Biopsy specimens were scored for fibrosis and necroinflammation according to the Knodell histology activity index (HAI). ResultsWhen b value was set as 800 s/mm2, statistical difference was showed between the fibrosis group and the nonfibrosis group, statistical difference was also shown among the different degrees of necroinflammation and fibrosis. ConclusionDWI is a valuable method for grading and staging of chronic viral hepatitis.
ObjectiveTo explore the significance of ultrasound combined with magnetic resonance imaging (MRI) in the diagnosis of pernicious placenta previa (PPP).MethodsA total of 101 patients with suspected PPP admitted to Chengdu Women’s and Children’s Central Hospital from January 2016 to February 2019 were retrospectively analyzed. The surgical results were used as the gold standard, and the diagnostic value of ultrasound, MRI, ultrasound combined with MRI was compared.ResultsSurgery results showed that among the 101 patients with suspected PPP, 79 patients had positive PPP diagnosis and 22 patients had negative PPP diagnosis. There was no significant difference in the diagnostic sensitivity, negative predictive value, or diagnostic coincidence rate of PPP among ultrasound, MRI, and ultrasound combined with MRI (P>0.05). The diagnostic specificity of the series combination of ultrasound and MRI (86.36%) was higher than that of ultrasound (59.10%), MRI (59.10%), and the parallel combination of ultrasound and MRI (31.32%), and the differences were statistically significant (P<0.05). The diagnostic coincidence rates of abnormal placental attachment of MRI (96.20%) and the parallel combination of ultrasound and MRI (96.20%) were higher than that of ultrasound (87.34%) and the series combination of ultrasound and MRI (87.34%) (P<0.05).ConclusionsUltrasound combined with MRI has a high diagnostic value for PPP. If necessary, ultrasound combined with MRI can be considered to improve the diagnostic efficiency.
【Abstract】Objective To compare radiologists’ performance on combined unenhanced and feridexs-enhanced MR imaging （MRI） with their performance on helical CT enhanced, unenhanced MRI, and feridexs-enhanced MR alone imaging for the characteristics of local hepatic lesions. Methods MR images and CT scans obtained in 26 patients with 57 local hepatic lesions were analyzed with reviewer operator characteristic (ROC) curve analysis. The imaging of patient were divided into 4 groups including combined unenhanced and feridexs-enhanced MRI group, helical CT enhanced group, unenhanced MRI group, and feridexsenhanced MR alone group. Results The combined approach resulted in larger area under the ROC curve (Az=0.926 0) and accuracy (86.8%),P＜0.05，as compared with the others methods. There were no significant differences among the other three methods. Conclusion Feridexs-enhanced MRI was more accurate than enhanced helical CT scan in characterization of local hepatic lesion. The combined analysis of unenhanced and feridexs-enhanced images was more accurate in the characterization of focal hepatic lesions than was review of feridexs-enhanced images alone.
Objective To review the current status of magnetic resonance imaging (MRI) techniques in the evaluation of hepatic fibrosis. Methods The application and recent advances of various kinds of MRI techniques in evaluating hepatic fibrosis were summarized by literature review. Results The state-of-the-art of MRI evaluating of hepatic fibrosis included common contrast-enhanced MRI, double contrast-enhanced MRI, and various functional MRI techniques. Common contrast-enhanced MRI could detect morphological changes of the liver, but little value in phasing. Double contrast-enhanced MRI markedly increased the contrast to noise ratio. Except diagnosis liver fibrosis, functional MRI also could phase it by its serverity. Conclusion MRI techniques, especially those functional MRI techniques, are advancing very fast and have very great potentiality in both the diagnosis and severity assessment of hepatic fibrosis.
Objective To investigate the effects on myocardial perfusion of simultaneous antegrade/retrograde cardiopiegia （SARC） through a single coronary artery and coronary sinus （CS）. Methods SARC was conducted in isolated pig hearts through CS in conjunction with the left anterior descending （LAD）, the left circumflex （LCX）, or the right coronary artery （RCA） respectively. After injecting magnetic resonance （MR） contrast agent （gadolinium diethyienetriamine pentaacetic acid, Gd-DTPA） into arterial or venous route, the distribution of Gd-DTPA with magnetic resonance imaging（MRI） was monitored and the effluent from the venting coronary arteries to assess the efficacy of SARC for myocardial perfusion was measured. Results Injection of Gd-DTPA into a perfusing artery during SARC resulted in increased signal intensity not only in the territory of the perfusing artery but also in the areas normally served by the other two venting coronary arteries （including the right ventrieuiar free wall）. With Gd DTPA given into the CS during SARC, the myocardium in the territories of the two venting coronary arteries was lightened. Signal intensity of the myocardium in the perfusing artery territory and right ventricuiar free wall remained unchanged. Moreover, a significant amount of effluent was collected from the venting coronary arteries during SARC： the LAD 10.5-17.7 ml/min; LCX 9.7-15.2 ml/min, and RCA 4.7-7.8 ml/min. Conclusion SARC through a single coronary artery and CS can provide homogeneous perfusion to the entire heart and is sufficient to prevent ischemic injury in the myocardium normally supported by the venting coronary arteries.
Objective To investigate the feasibility of imaging of bone marrow mesenchymal stem cells (BMMSCs) labeled with superparamagnetic iron oxide(SPIO) transplanted into coronary artery in vivo using magnetic resonance imaging (MRI), and the redistribution of the cells into other organs. Methods BMMSCs were isolated, cultured from bone marrow of Chinese mini swine, and double labeled with SPIO and CMDiI(Cell TrackerTM C-7001). The labeled cells were injected into left anterior descending coronary artery through a catheter. The injected cells were detected by using MRI at 1 week,3weeks after transplantation. And different organs were harvested and evaluated the redistribution of transplanted cells through pathology. Results The SPIO labeled BMMSCs injected into coronary artery could be detected through MRI and confirmed by pathology and maintained more than 3 weeks. The SPIO labeled cells could be clearly imaged as signal void lesions in the related artery. The pathology showed that the injected cells could be distributed into the area of related artery, and the cells injected into coronary artery could be found in the lung, spleen, kidney, but scarcely in the liver, the structures of these organs remained normal. Conclusion The SPIO labeled BMMSCs injected into coronary artery can be detected by using MRI, the transplanted cells can be redistributed into the non-targeted organs.
ObjectiveTo investigate the value of magnetic resonance (MR) imaging in the assessment of bile duct complications after cholecystectomy. MethodsFifty patients of having bile duct complications after cholecystectomy underwent MR imaging and had some positive manifestations. The indication for cholecystectomy was symptometic cholelithiasis in all cases. MR imaging was performed with a 1.5T clinical imager including all of the sequences of: ①T1 weighted imaging (T1WI) was performed in transverse and coronal plane before and after gadolinium-enhanced. ②T2 weighted imaging (T2WI) was performed in transverse plane. ③A true fast imaging with steadystate precession sequence (True fisp) was performed in coronal plane. ④MR cholangiopancreatography was also obtained. ResultsThe bile duct complications after cholecystectomy including: 22 cases of cholelithiasis, 15 cases of chronic cholangitis with or without bile duct abscess. Bile duct strictures or abruption at the confluence of hepatic and common bile duct in 6 and 3 cases respectively. Tumors of bile duct or pancreas in 9 cases. The other complications after cholecystectomy including bile leak with choleperitonitis and/or biloma and acute pancreatitis.ConclusionMR imaging was a valuable method for the assessment of bile duct complications after cholecystectomy. MR imaging could assess the etiology of bile duct complications. If there were bile duct obstruction, MR imaging could assess the location and the severe of obstruction. For bile duct or pancreatic tumors, MR imaging could assess the areas of tumor infiltration and resection and was helpful to select treatment methods. Before lapatoscopic cholecystectomy, the overall and careful imaging assessment for bile duct and gallbladder and its adjacent hepatic tissue and pancreas so to avoid missing the relative tumors.
Objective To investigate the value of magnetic resonance (MR) imaging for diagnosing typeⅠ congenital choledochocele and its complications. Methods The MR imaging data of 13 cases with proved typeⅠ congenital choledochocele associated with complications were retrospectively reviewed and compared with operative findings. MR imaging sequences included axial T2W and T1W plain scan, true-FISP coronal images, 2D-MRCP, and Gd-enhanced T1W images. Results All patients had cystic dilatation of the common bile ducts to various degrees. In 6 patients complicated with stone and infection, the bile duct showed uniform wall thickening with marked enhancement, and calculus were depicted within the duct lumen with dilatation of the proximal biliary duct. In 7 cases complicated with carcinoma of biliary duct, a polypoid soft tissue mass or nodule was seen inside the ductal lumen in 3 cases, or the duct wall was irregularly thickened in 4 patients. Six cases received curative operation, but one patient with extensive local infiltration, vascular encasement and lymphadenopathy had only palliative treatment. MR imaging observations were verified by surgery findings in all 13 patients.Conclusion MR imaging is very valuable not only in diagnosing typeⅠ congenital choledochocele, but also in revealing its complications.
Objective To investigate the relationship between Oxfordshire community stroke project (OCSP) classification and MRI classification in acute cerebral infarction. Methods A total of 282 patients with acute cerebral infarction were retrospectively evaluated with OCSP classification and imaging characteristics. Results According to OCSP classification, of all 282 patients with acute cerebral infarction, 32 (11.3%) experienced total anterior circulation infarction (TACI), 86 (30.5%) partial anterior circulation infarction (PACI), 111 (39.4%) lacunar infarction (LACI), and 53 (18.8%) posterior circulation infarction (POCI). The consistency was found in 201 cases (71.3%) between the OCSP classification and imaging classification, with the accuracy of 77% (27/35) for TACI, 79% (42/53) for PACI, 69% (95/137) for LACI and 65% (37/57) for POCI. Conclusion OCSP classification can predict the location and size of cerebral infarction with a high accuracy, and is well consistent with the MRI findings.
