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Extrahepatic cholangiocarcinoma is often clinically challenging to diagnose. Even multidisciplinary approaches which include computed tomography, magnetic resonance imaging, and endoscopic retrograde cholangiography are unsatisfactory in some cases, especially with biliary stricture. Percutaneous transhepatic cholangioscopy (PTCS) with its direct visualization for biopsy appears to be a promising technique for detecting cholangiocarcinoma at an early stage. We report a case of adenocarcinoma in situ of the distal common bile duct (CBD) that was confirmed by PTCS. This case suggests the useful role of PTCS in the differential diagnosis of a distal CBD obstruction, particularly when other diagnostic modalities do not provide definitive information.  相似文献   
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Background: Atrial septal defect (ASD) is one of the most common congenital heart diseases. Nowadays, percutaneous closure is considered the treatment of choice in most of secundum ASDs. Assessment of the defect and procedure monitoring have been usually performed by angiographic balloon‐sizing and/or two‐dimensional (2D) transesophageal echocardiography. However, in complex ASDs these techniques might be inaccurate. Methods: From January 2009 to January 2011 all adult patients with complex ASDs submitted for percutaneous closure were selected. Those defects, where shunts were present through a device previously implanted on the atrial septum or through multiperforated septums, were considered complex ASDs. Two‐dimensional transesophageal echocardiography and real time three‐dimensional (3D) echocardiography were performed simultaneously during the percutaneous closure procedure. Number of orifices, relationships between the defect, catheter, and device, as well as residual shunt were assessed. Results: Seven patients were included. Five patients had a multiperforated septum and in two cases the defect in the septum was through a previously implanted device. In all cases, 3D echocardiography was superior to 2D echocardiography in relation to the assessment of the relationship between the defect and the catheter or the device. Mechanisms responsible for residual shunts through a device were also better assessed by 3D echocardiography. Conclusion: Three‐dimensional echocardiography is a safe and useful technique when monitoring percutaneous closure of ASDs, showing relevant advantages over 2D echocardiography. (Echocardiography 2012;29:729‐734)  相似文献   
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