Objective To investigate the situation of MRI examination in children in outpatient and inpatient departments of the Sichuan Provincial People’s Hospital from 2010 to 2012, so as to provide favourable basis for the choice of imaging examination in children. Methods The materials of electronic reports of MRI examination in paediatric inpatient and outpatient departments from 2010 to 2012 were collected, categorized, and analyzed. Results a) 2 148 children underwent MRI examination in the Sichuan Provincial People’s Hospital from 2010 to 2012. The total number of patients increased with year. Boys were more than girls. The positive incidence was slightly decreased. The number of outpatients was more than inpatients, but the positive incidence was lower in outpatients. b) The total numbers of examination position were increased with year and the number of single position examination was the most (accounted for than 85% of the total numbers). The main examination positions included: head, MRA of the head, cervical column, knees, lumbar column, pituitary gland, thoracic column, and abdomen. The examination positions diversified gradually. The application of examination technique also increased gradually. c) The systemic disease spectrum of positive cases in MRI examination included 9 categories, which accounted for 42.86% of ICD-10. The nervous systematic disease, muscle, skeleton and connective tissue disease were the categories. The major disease types were stable during the recent 3 years. The increase was obvious in injuries of the knees, malacosis and atrophy of the brain, the deformity of the brain. Conclusion The total numbers of the patients and positions examined increased gradually with year in the Sichuan Provincial People’s Hospital from 2010 to 2012. The applications of MRI in the head, limbs and joints, and soft tissues were more extensive. Children diagnosed as positive results had diseases of the central nervous system, limbs and joints, and connective tissue disease.
Objective To summarize and analyze the MRI imaging findings of advanced gastric cancer in order to improve the level of image diagnosis. Methods The plain and dynamic enhanced MRI findings in 8 volunteers and 30 patients with pathologically proven advanced gastric cancer were retrospectively analyzed. Results The stomach wall of advanced gastric cancer was inhomogeneous thickening with iso intensity or little hypo intensity signal on T1WI， and iso intensity or little hyper intensity signal on T2WI. Cases with serosal infiltration， the serous appearred indistinctly and rough. In some cases， the low signal zones between gastic wall and fat space were interrupted on T1WI out-of-phase image. Cases with adjacent organs invaded， the fat space was rough or disappeared. The lesions showed obvious irregular or hierarchy enhancement on MRI dynamic contrast scanning. Conclusions Inhomogeneous thickening of gastic wall with abnormal signal intensity， indistinctness or disappearance of fat space， irregular or hierarchy enhancement are very valuable as diagnostic signs in patients suspective of advanced gastric cancer.
Objective To investigate the diagnostic value of a double action MR contrast agent——gadobenate dimeglumine （Gd-BOPTA） for focal liver lesion and biliary system disease. Methods Articles about Gd-BOPTA in CNKI and PubMed for the past few years were searched and the value of Gd-BOPTA in the diagnosis of focal liver lesion and biliary system disease was summarized. Results For focal liver lesion, Gd-BOPTA not only can reveal blood supply of the lesion, but also reveal the hepatocellular functional status in the lesion. For biliary system, biliary excretion of Gd-BOPTA can be used to evaluate the anatomic structure of bile duct， function of gallbladder and biliary system disease. Conclusions Gd-BOPTA has an important value in the diagnosis of focal liver lesion and biliary system disease. Gd-BOPTA may have wider applications in the future.
Objective To summarize the principle and application of functional MR imaging of pancreatic carcinoma and chronic mass-forming type pancreatitis. Methods Articles about diffusion-weighted imaging (DWI), magnetic resonance spectrum imaging (MRSI) and dynamic contrast-enhanced MR imaging of pancreatic carcinoma and chronic pancreatitis were reviewed and analyzed. Results Functional MR imaging could reflected the differences in molecules diffusion, metabolism and tissue perfusion between pancreatic carcinoma and chronic pancreatitis. Conclusion As a non-invasive protocol, functional MR imaging can provide useful information in differential diagnosis between chronic mass-forming type pancreatitis and pancreatic carcinoma.
Objective To evaluate the value of medical imaging technology in qualitative and quantitative diagnosis of liver steatosis. Methods To describe the current status and advancement s of medical imaging technology such as sonography , CT and MRI in qualitative and quantitative diagnosis of liver steatosis , and to cont rast their advantages and shortages. Results Sonography could be used as the primary screening and evaluate measures in qualitative and quantitative diagnosis of liver steatosis , and CT was more reliable in quantitative diagnosis , MRI had significant improving with its high sensitivity and specificity. Conclusion Medical imaging technology has significant clinical value in qualitative and quantitative diagnosis of liver steatosis , especially with the help of functional MR imaging techniques such as spect roscopy and chemical shif t Gradient-Echo technic.
【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.
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.
ObjectiveTo investigate the CT and MR imaging features and distribution characteristics of lymphatic nodal involvement in patients with gallbladder carcinoma. MethodsThirtyseven histopathologically proven cases of gallbladder carcinoma with regional lymphatic nodal enlargement in upper abdomen were included into the study. The lymph nodal short diameter of equal to or larger than 10 mm was used as the criteria for positive lymphadenopathy. Thirtyone cases underwent contrastenhanced spiral CT scanning, 6 cases had MR imaging studies. CT and MR images were jointly evaluated by three radiologists with especial attention to the size and location of enlarged lymph nodes in upper abdomen.ResultsThe enlarged lymph nodes were observed in four anatomic locations in the upper abdominal region. ①The retroportal and retropancreatic group in which lymph nodes were located along the cystic duct and common bile duct, in the portocaval space and behind the pancreatic head. ②The celiac group in which enlarged nodes distributed along the common hepatic artery and surrounded the celiac trunk. ③The mesenteric group in which lymph nodes assembled at the mesenteric root and around the superior mesenteric vessels. ④The abdominal aorta group in which lymph nodes scattered at the left side of abdominal aorta and in the aortocaval space at the level of the left renal vein. The spiral CT visualization rates for the above 4 groups of lymphadenopathy were 89.1%(33/37), 78.3%(29/37), 29.8%(11/37) and 51.3%(19/37) respectively.ConclusionCT and MR can clearly depict the four location sites of lymphadenopathy in patients with gallbladder carcinoma, which closely reflects the three major lymphatic spreading pathways of gallbladder carcinoma, namely, the cholecystoretropancreatic, cholecystoceliac and cholecystomesenteric routes.
ObjectiveTo introduce the new nomenclature scheme of the International Working Group (1995) on hepatic nodules, and summarize the imaging features of various hepatic nodules in light of their pathological characteristics, and evaluate the diagnostic values of various imaging facilities.MethodsUltrasound, computed tomography(CT), magnetic resonance imaging(MRI), and angiographic CT were reviewed and introduced.ResultsMany of these types of hepatic nodules play a role in the de novo and stepwise carcinogenesis of hepatocellular carcinoma(HCC) in the following steps: regenerative nodule, lowgrade dysplastic nodule, highgrade dysplastic nodule, small HCC, and large HCC. Accompanying such transformations, there are significant alterations in the blood supply and perfusion of these hepatic nodules.ConclusionModern stateoftheart medical imaging facilities can not only delineate and depict these hepatic nodules, but also provide important clues for the characterization of focal hepatic lesions in most cases, thus facilitating the early detection, diagnosis and management of HCC in its early stage.
Magneticaly labeled stem cells and magnetic resonance imaging(MRI) technology is an effective tracking method in vivo study, which has high spatial-temporal resolution. Gadolinium, which shows positive T1 signals and iron oxide showing negative T2 signals are the two often used contrast agents. The latter also include superparamagnetic iron oxide particle and ultrasmall superparamagnetic iron oxide particle. Transfection agents, e.g. poly-L-lysine and protamine sulfate，can enhance magnetical nanoparticles labeling stem cells. The biological characteristics of labeled stem cells did not seem to be altered. MRI can detect the labeled stem cells’ signals and also can track changes of signal in intensity and size with time past. In conclusion, MRI tracking magneticaly labeled stem cells represents a method for noninvasivly monitoring the existence and migration of engrafts.