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A 66-year-old male patient presented with nausea, abdominal pain, occasional rectal bleeding, progressive dysgeusia, onicodystrophy, and alopecia. Endoscopic exam and biopsies revealed severe atrophy and diffuse marked edema of mucosa of stomach and duodenum. No evidence of polyps was found in any portion of the gastrointestinal tract. The diagnosis of Cronkhite–Canada syndrome (CCS) was rendered. The patient symptoms resolved completely after initiation of steroid treatment. This additional case of CCS illustrates how the diagnosis of CCS does not require the presence of polyps but is defined by the appreciation of the diffuse marked edema and atrophy of the gastrointestinal mucosa.

BACKGROUND AND OBJECTIVE: Simulation-based medical education (SBME) is used to teach residents. However, few studies have evaluated its clinical impact. The goal of this study was to evaluate the impact of an SBME session on pediatric interns’ clinical procedural success. METHODS: This randomized trial was conducted at 10 academic medical centers. Interns were surveyed on infant lumbar puncture (ILP) and child intravenous line placement (CIV) knowledge and watched audiovisual expert modeling of both procedures. Participants were randomized to SBME mastery learning for ILP or CIV and for 6 succeeding months reported clinical performance for both procedures. ILP success was defined as obtaining a sample on the first attempt with <1000 red blood cells per high-power field or fluid described as clear. CIV success was defined as placement of a functioning catheter on the first try. Each group served as the control group for the procedure for which they did not receive the intervention. RESULTS: Two-hundred interns participated (104 in the ILP group and 96 in the CIV group). Together, they reported 409 procedures. ILP success rates were 34% (31 of 91) for interns who received ILP mastery learning and 34% (25 of 73) for controls (difference: 0.2% [95% confidence interval: –0.1 to 0.1]). The CIV success rate was 54% (62 of 115) for interns who received CIV mastery learning compared with 50% (58 of 115) for controls (difference: 3% [95% confidence interval: –10 to 17]). CONCLUSIONS: Participation in a single SBME mastery learning session was insufficient to affect pediatric interns’ subsequent procedural success.

PurposeTo investigate the influence of portal pressure on the shear stiffness of the liver and spleen in a well‐controlled in vivo porcine model with magnetic resonance elastography (MRE). A significant correlation between portal pressure and tissue stiffness could be used to noninvasively assess increased portal venous pressure (portal hypertension), which is a frequent clinical condition caused by cirrhosis of the liver and is responsible for the development of many lethal complications.Materials and MethodsDuring multiple intraarterial infusions of Dextran‐40 in three adult domestic pigs in vivo, 3D abdominal MRE was performed with left ventricle and portal catheters measuring blood pressure simultaneously. Least‐squares linear regressions were used to analyze the relationship between tissue stiffness and portal pressure.ResultsLiver and spleen stiffness have a dynamic component that increases significantly following an increase in portal or left ventricular pressure. Correlation coefficients with the linear regressions between stiffness and pressure exceeded 0.8 in most cases.ConclusionThe observed stiffness–pressure relationship of the liver and spleen could provide a promising noninvasive method for assessing portal pressure. Using MRE to study the tissue mechanics associated with portal pressure may provide new insights into the natural history and pathophysiology of hepatic diseases and may have significant diagnostic value in the future. J. Magn. Reson. Imaging 2013;38:809–815. © 2013 Wiley Periodicals, Inc.

PurposeThe goal of this work was to detect disease‐related microstructural changes to the liver using magnetic resonance imaging. Chronic liver disease can cause microstructural changes in the liver that reduce plasma access to the perisinusoidal space—the site of exchange between the blood plasma and the hepatic parenchyma. The reduced plasma access to the perisinusoidal space inhibits hepatic function and contributes to the ∼30,000 chronic liver disease‐related deaths per year.MethodsThe extracellular matrix‐specific cationized ferritin magnetic resonance imaging probe was injected intravenously into healthy rats and a rat model of the chronic liver disease non‐alcoholic steatohepatitis. Rats were subsequently imaged with ‐weighted magnetic resonance imaging.ResultsThis work demonstrates that the binding of cationized ferritin to the perisinusoidal extracellular matrix is reduced by 55% in a rat model of non‐alcoholic steatohepatitis compared to healthy controls. This reduced binding is detectable in vivo with magnetic resonance imaging. Immunofluorescence and electron microscopy indicated that the reduced binding is due to inhibited macromolecular access to the perisinusoidal space caused by non‐alcoholic steatohepatitis‐related microstructural changes.ConclusionsThe reduced accumulation of intravenously injected cationized ferritin may report on changes in macromolecular access to the liver parenchyma in chronic liver disease. Magn Reson Med 70:1728–1738, 2013. © 2013 Wiley Periodicals, Inc.

PurposeTo investigate the feasibility of using MR elastography (MRE) for the evaluation of the stiffness of in vivo aortic wall.Materials and MethodsTo validate the experimental approach for imaging the aorta in vivo, a gel phantom with an embedded porcine aorta was imaged in the presence of fluid flow within the aorta. The potential changes in the elasticity of the vessel wall with changes in pressure were investigated. The feasibility of performing MRE of abdominal aorta was assessed in five volunteers (age, 22–40 years; body mass index, 21.5–25.2 kg/m2). The pulse‐gated cine MRE technique was used to study the wave propagation along the aorta throughout the cardiac cycle and provide estimates of aortic stiffness in diastole.ResultsIn the phantom study, the wave propagation was well visualized within the porcine aorta embedded in the gel phantom. An increase of the Young's modulus‐wall thickness (E*t) product with the increase in static pressure was observed. In the in vivo study, the waves were well visualized within the lumen of abdominal aorta in the five volunteers in diastolic phase, but they were not well visualized during systole.ConclusionMRE is feasible for noninvasively assessing the stiffness of the abdominal aorta and merits further investigation. J. Magn. Reson. Imaging 2013;38:1549–1553. © 2013 Wiley Periodicals, Inc.