Benign hepatic tumors are commonly observed in adults,but rarely reported in children.The reasons for this remain speculative and the exact data concerning the incidence of these lesions are lacking.Benign hepatic tum...Benign hepatic tumors are commonly observed in adults,but rarely reported in children.The reasons for this remain speculative and the exact data concerning the incidence of these lesions are lacking.Benign hepatic tumors represent a diverse group of epithelial and mesenchymal tumors.In pediatric patients,most benign focal liver lesions are inborn and may grow like the rest of the body.Knowledge of pediatric liver diseases and their imaging appearances is essential in order to make an appropriate differential diagnosis.Selection of the appropriate imaging test is challenging,since it depends on a number of age-related factors.This paper will discuss the most frequently encountered benign liver tumors in children(infantile hepatic hemangioendothelioma,mesenchymal hamartoma,focal nodular hyperplasia,nodular regenerative hyperplasia,and hepatocellular adenoma),as well as a comparison to the current knowledge regarding such tumors in adult patients.The current emphasis is on imaging features,which are helpful not only for the initial diagnosis,but also for pre- and posttreatment evaluation and follow-up.In addition,future perspectives of contrast-enhanced ultrasound(CEUS) in pediatric patients are highlighted,with descriptions of enhancement patterns for each lesion being discussed.The role of advanced imaging tests such as CEUS and magnetic resonance imaging,which allow for non-invasive assessment of liver tumors,is of utmost importance in pediatric patients,especially when repeated imaging tests are needed and radiation exposure should be avoided.展开更多
Inflammatory bowel diseases(IBD) represent challenges, both from a diagnostic, and therapeutic point of view. Deep-seated anatomic structures are difficult to assess by ultrasound technique alone. As radiation-free al...Inflammatory bowel diseases(IBD) represent challenges, both from a diagnostic, and therapeutic point of view. Deep-seated anatomic structures are difficult to assess by ultrasound technique alone. As radiation-free alternative cross-sectional imaging method, magnetic resonance imaging of the intestinal structures is costly and time-consuming. Examination of pediatric patients imply additional considerations: reduction of body motions in younger children and consideration of the most appropriate preparation, and examination technique. The demanding Sellink technique is the only means for appropriately distending the lesser intestine in order to detect small bowel strictures. Oral intake of contrast medium(CM) alone shows its limitations regarding distensibility. The need for intravenous contrast media application needs to be considered, too. Active inflammation of both intestinal wall, and mesentery can be demonstrated accurately. Nevertheless, viable alternatives to CM application is desirable, considering non-negligible adverse reactions. Recent data suggest diffusion weighted imaging might fill this diagnostic gap. Irrespective of sequence technique chosen, bowel movement remains a major obstacle. Antispasmolytics in their function as smooth muscle relaxants help in improving image quality, however, their use in children might be off-label. Optimal preparation for the examination and appropriate imaging technique allow for diagnosing typical patterns of changes in IBD, such as bowel wall thickening, ulcers, mural stratification, strictures, creeping fat, and comb sign, and lymphadenopathy. The article gives a detailed overview of current significance of magnetic resonance imaging pediatric patients suffering from IBD, considering indications, limitations, and safety aspects.展开更多
文摘Benign hepatic tumors are commonly observed in adults,but rarely reported in children.The reasons for this remain speculative and the exact data concerning the incidence of these lesions are lacking.Benign hepatic tumors represent a diverse group of epithelial and mesenchymal tumors.In pediatric patients,most benign focal liver lesions are inborn and may grow like the rest of the body.Knowledge of pediatric liver diseases and their imaging appearances is essential in order to make an appropriate differential diagnosis.Selection of the appropriate imaging test is challenging,since it depends on a number of age-related factors.This paper will discuss the most frequently encountered benign liver tumors in children(infantile hepatic hemangioendothelioma,mesenchymal hamartoma,focal nodular hyperplasia,nodular regenerative hyperplasia,and hepatocellular adenoma),as well as a comparison to the current knowledge regarding such tumors in adult patients.The current emphasis is on imaging features,which are helpful not only for the initial diagnosis,but also for pre- and posttreatment evaluation and follow-up.In addition,future perspectives of contrast-enhanced ultrasound(CEUS) in pediatric patients are highlighted,with descriptions of enhancement patterns for each lesion being discussed.The role of advanced imaging tests such as CEUS and magnetic resonance imaging,which allow for non-invasive assessment of liver tumors,is of utmost importance in pediatric patients,especially when repeated imaging tests are needed and radiation exposure should be avoided.
文摘Inflammatory bowel diseases(IBD) represent challenges, both from a diagnostic, and therapeutic point of view. Deep-seated anatomic structures are difficult to assess by ultrasound technique alone. As radiation-free alternative cross-sectional imaging method, magnetic resonance imaging of the intestinal structures is costly and time-consuming. Examination of pediatric patients imply additional considerations: reduction of body motions in younger children and consideration of the most appropriate preparation, and examination technique. The demanding Sellink technique is the only means for appropriately distending the lesser intestine in order to detect small bowel strictures. Oral intake of contrast medium(CM) alone shows its limitations regarding distensibility. The need for intravenous contrast media application needs to be considered, too. Active inflammation of both intestinal wall, and mesentery can be demonstrated accurately. Nevertheless, viable alternatives to CM application is desirable, considering non-negligible adverse reactions. Recent data suggest diffusion weighted imaging might fill this diagnostic gap. Irrespective of sequence technique chosen, bowel movement remains a major obstacle. Antispasmolytics in their function as smooth muscle relaxants help in improving image quality, however, their use in children might be off-label. Optimal preparation for the examination and appropriate imaging technique allow for diagnosing typical patterns of changes in IBD, such as bowel wall thickening, ulcers, mural stratification, strictures, creeping fat, and comb sign, and lymphadenopathy. The article gives a detailed overview of current significance of magnetic resonance imaging pediatric patients suffering from IBD, considering indications, limitations, and safety aspects.