Objective To review the principles and techniques of CT perfusion imaging and its applications in the imaging diagnosis of abdominal disorders. Methods All the relevant literatures were reviewed. The principles and techniques of CT perfusion imaging were described and summarized in detail. The functional information of a target abdominal organ (e.g. the liver and pancreas) revealed by CT perfusion imaging, such as hemodynamics and microcirculation status, was also evaluated. Results In addition to the morphologic information, CT perfusion imaging can also provide functional information about the circulation parameters of target abdominal organs. Moreover, such functional information can be generated for the neovasculature and microcirculation of tumor lesions of abdominal organs, which is very helpful for not only the diagnosis, but also the evaluation of tumor invasiveness and response to treatment. Conclusion CT perfusion imaging offers an effective method for studying abdominal disorders by providing functional information that is quite useful for the differential diagnosis and assessment of therapeutic response.
Objective To introduce the imaging modalities used for the evaluation of postoperative complications of orthotopic liver transplantation (OLT) and to present the imaging findings of these complications. Methods The literatures related to the imaging methods and imaging manifestations of OLT complications were reviewed. Results Ultrasound was the initial imaging technique used for the detection of complications in the early postoperative period. Spiral CT and MRI yielded more accurate and comprehensive evaluation of postoperative complications in later stage. So far, there had been no specific imaging findings to suggest rejection reaction. The spectrum of imaging manifestations of OLT complications, such as vascular complications, biliary complications, liver parenchymal complications, and so on, were summarized and illustrated. Conclusion Imaging examination (especially ultrasound, spiral CT and MRI ) plays an important role in the evaluation of postoperative complications of OLT.
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.
ObjectiveTo evaluate the diagnostic value of CT, MRI, and magnetic resonance cholangiopancreatography (MRCP) in the localization and qualitative diagnosis of biliary obstruction.MethodsA total of 80 patients with biliary obstruction in our hospital from January 2018 to June 2020 were retrospectively collected. The patients were all examined by CT, MRI, and MRCP. The imaging images of all patients were interpreted by two radiologists with more than 5 years of working experience. Taking the results of operation and histopathology as the gold standard, the diagnostic value of CT, MRI+MRCP, CT+MRI+MRCP in the localization and qualitative diagnosis of biliary obstruction lesions were evaluated.ResultsCompared with the location results of surgery and histopathology, the coincidence rates of CT+MRI+MRCP and MRI+MRCP were higher than that of CT (P<0.05), but there was no significant difference between CT+MRI+MRCP and MRI+MRCP (P>0.05); compared with the benign and malignant results of surgery and histopathology, the coincidence rates of CT, CT+MRI+MRCP and MRI+MRCP were close, and there was no statistical significance among them (P>0.05).ConclusionsMRI+MRCP and CT+MRI+MRCP have the same value in the localization and qualitative diagnosis of biliary obstruction. However, MRI+MRCP have the advantages ofnon-radiation or contrast media, it is more suitable for patients who are worried about the impact of radiation, have contrast media allergy or renal insufficiency.
Objective To investigate the CT manifestations of acute pancreatitis (AP) and its complications and to evaluate the imaging modalities for staging the severity of AP. Methods Literatures on CT manifestations of AP and its complications and severity staging of AP were reviewed.Results CT has shown an early overall detection rate of 90% for pancreatic necrosis with close to 100% sensitivity 4 days after episode. The CT severity index has shown a bly positive correlation with the development of local complications and mortality of AP.Conclusion Contrastenhanced CT is the imaging modality of choice to help detect pancreatic necrosis, stage the severity of the inflammatory processes, and depict local complications.
Objective To summarize the research status and progress of imaging diagnosis of periampullary carcinoma. Methods The literatures on imaging diagnosis of periampullary carcinoma were reviewed. Results At present, the commonly used imaging diagnosis methods for periampullary carcinoma mainly include ultrasound, CT, MRI, and endoscopic retrograde cholangiopancreatography. Some other new imaging techniques had also been applied in the diagnosis and evaluation of periampullary carcinoma. Conclusions Different imaging methods have their own advantages and disadvantages in the diagnosis of periampullary carcinoma. Therefore, the detection rate and diagnostic accuracy of periampullary carcinoma can be improved by rational selection of imaging techniques or combined application of multiple techniques.
Objective To review the CT appearances and important differential diagnoses of various primary and secondary mesenteric neoplasms. Methods By describing the mesenteric anatiomy and major routes for the dissemination of metastatic mesenteric tumors, the article presents both the common and rare types of various primary and secondary mesenteric neoplasms, and addresses the characteristic CT appearances and important aspects of the differential diagnosis. Results CT study, especially the multislice spiral CT (MSCT), along with the clinical history and other related information, can nicely depict various mesenteric tumors and well differentiate them from infectious, inflammatory or vascular processes affecting the mesentery. Conclusion CT is the imaging method of choice for the evaluation of tumors of small bowel mesentery.
ObjectiveTo summarize the research progress of CT related to esophageal varices of cirrhotic patients complicated with portal hypertension.MethodsRelevant CT literatures of esophageal varices of cirrhotic patients complicated with portal hypertension were collected to make an review,then summarized the research status and progress of CT in the diagnosis and evaluation of lower esophageal varices.ResultCT had a good correlation with endoscopic diagnosis of esophageal varices, and CT was of great value in evaluating the presence, degree, and risk of esophageal varicose veins, especially in predicting the risk of esophageal varicose veins, which could be used as an effective modality to assist endoscopic examination to a certain extent.ConclusionsCT is an important examination method for esophageal varices, which has important value in diagnosis and evaluation. In the future, more further researches can be carried out to provide more strong and accurate support for the diagnosis and treatment of esophageal varices.
ObjectiveTo summarize the application of magnetic resonance imaging (MRI) in the evaluation of pancreatic exocrine function.MethodIn this paper, we reviewed and summarized the related literatures about the application of MRI in the field of pancreatic exocrine function evaluation in recent years.ResultsA variety of MRI techniques could be used to detect the pancreatic exocrine function. In addition to conventional MRI techniques, there were also MRI stimulated by pancreatic secretions, cine (dynamic) cholangiopancreatography based on space selective reverse recovery pulse, and so on.ConclusionThe new MRI techniques have potential for semi-quantitative and quantitative evaluation of pancreatic exocrine function.
Objective To summary the principle of magnetic resonance spectroscopy imaging and its application progress in diagnosis and differential diagnosis of pancreatic cancer. Methods The newest related literatures of home and abroad were collected and reviewed. Results Magnetic resonance spectroscopy imaging was a technology using the magnetic resonance phenomena and chemical shift phenomena to measure molecular organization. The spectroscopy most commonly used in clinical and scientific research includes 1H， 31P， and 23Na. Conclusion Magnetic resonance spectroscopy as the only approach to noninvasive quantitative provding biochemical information in vivo， has an important significance to the diagnosis and differential diagnosis of pancreatic cancer.
