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Abstracts haustration not present. The five-layer structure remained, and the individual layers, particularly lumen-attached layer 1 and layer 2, are more clearly visible. (6) Colon tuberculosis: Ileocaecum and jejunum are involved. Ultrasound findings are focal thickening of wall up to 15 cm, concentric thickening and narrowing of terminal ileum and caecum, terminal ileum and caecum pulled up, valve deformed, lymph nodes enlarged. Hydrocolonosonography is an alternate modality of imaging the colon. It is a cheap, rapid and well-tolerated procedure. In a country like Bangladesh, this procedure can be applied without involving significant amount of extra money and manpower. 1066 Trans-abdominal ultrasound of the alimentary tract in the tropics Kawooya M, Makerere University Kampala, Uganda Trans-abdominal ultrasound is a noninvasive, affordable method of imaging the alimentary tract. The ultrasound techniques used include conventional ultrasound using 3-5 MHz transducer, high resolution, Doppler ultrasound and hydrocolosonography. Ultrasound signs of disease are focal or generalised wall thickening, disruption of the five layers wall structure, intra-luminal mass lesions, extrinsic mass effects, abnormal vascular pattern and abnormal gut motility. This lecture deals with the use of trans-abdominal ultrasound in conditions seen in the tropics which include congenital and acquired diseases. Emphasis in on inflammatory conditions, parasitic and HIV/AIDS related pathologies like tuberculosis and lymphoma. This talk is illustrated with over 30 cases investigated by the author. For some of these, ultrasound guided biopsy has been employed to establish the diagnosis. In the tropics, where expertise as well as availability of endoscopic services is not readily available, trans-abdominal ultrasound has offered a cheaper, quicker, hygienic and versatile alternative. 1067 From esophagus to rectum: Diagnostic benefits and limits of conventional transcutaneous ultrasound Greiner L, University of Witten, Germany Transcutaneous ultrasonography (US) is an excellent modality not only in imaging the gastrointestinal tract (GIT) but in evaluating its functions as well by observing peristalsis and the quantity and quality of intestinal contents. The normal wall structures in US are depicted as three layers. The first part of the GIT, the cervical esophagus, is well delineable behind the left lobe of the thyroid gland (rare behind the right lobe). The esophageal mid-portion is covered and not accessible to US, whereas the terminal esophagus and the cardia can be defined in almost every individual. In patients with dysphagia, routine US examination should focus on this area, looking for the general features of GIT pathology: asymmetric wall thickening with partial or complete loss of the layered structures (“pathological cocarde”) mostly rule echopoor, with a loss of peristaltic movements, and a prestenotic dilatation and pathologically enhanced fluid contents. These pathologies mean in the stomach a sometimes considerable wall thickening, due to malignancies of various origins (which of course cannot be differentiated by means of US). Once they form an obstacle, a gastric retention will follow, or other clinical signs will prompt diagnostic efforts. The duodenum as the first part of the small intestine, hardly delineable in normal conditions, is often involved in pancreatitis with an overall swelling of its wall structures with good visibility. This holds true in other diffuse inflammatory reactions of the small intestine as well as e.g., in gluten sensitive enteropathy or in less a degree in severe infectious enteritis. Subileus or ileus will be detected by US earlier than by X-ray diagnostics, since US is not depending from separating gas formations, dilatation and pathological peristalsis are directly and re-

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peatedly easily demonstrated by US. Finding the obstacle, for example in Crohn‘s disease, needs a more detailed examination but it is as a rule possible to find the site of the intestinal blockade (be it by compression or by luminal obstruction) and to either define the true nature of the blockage or to give at least a good differential diagnostic approach to the most probable reason(s). Ileocecal junction and the valve are as a rule not visible in healthy individuals. In augmented intestinal liquid filling, however, they can be defined easily including their possible pathology. Appendicitis, still sometimes a really difficult clinical diagnosis, can be defined in the classic cases without a problem, confirming the clinical findings and quickening the indication for operation. Colon pathology, both in inflammatory and in tumorous processes, is an ideal target for clinical ultrasonography as well, predicting quite often the endoscopic findings. Hydrocolonosonography is another early variant of virtual colonoscopy, a merely considered but true fact with the drawback of too low an economic challenge or promise. In conclusion, intestinal US, starting with the esophagus and ending with the rectum, is an ideal noninvasive diagnostic approach in GIT disease, and an optimum partner for endoscopical intestinal diagnosis.

ECHOCARDIOGRAPHY FOR CLINICAL INTERVENTION 1068 Transesophageal echocardiography during transcatheter closure of atrial septal defect Chiang C-W, Cathay General Hospital, Taiwan Transcatheter closure of atrial septal defect (ASD) of the secumdum type has emerged as a promising therapeutic option, which compares favorably versus surgery in terms of patient’s acceptability, length of hospital stay and complication rate. Echocardiography plays an important role before, during and after the procedure. Before the procedure, echocardiography can determine the location, shape, size and number of the defects, which are crucial for the formulation of optimal therapeutic strategies. It can effectively detect associated lesions and evaluate pulmonary artery pressure and global cardiac functions, which are also important for decision-making. During the procedure, online transesophageal echocardiography is indispensable. It can be performed with or without general anesthesia and endotracheal intubation. Fluoroscopy time and radiation hazards can be greatly reduced. It can trace the path of the catheters, measure the balloon-stretched diameter of the defect, avoid device-induced interference with the atrioventricular valves, pulmonary veins, coronary sinus or inferior vena cava, check the completeness of closure and detect complications, thereby facilitates the procedure and enhance the safety. After the procedure, echocardiography can serve as a simple, reliable and practical tool for clinical follow-up, which would be accepted by most patients. Thus, expertise in echocardiography is mandatory for successful transcatheter closure of ASD. 1069 Visualization and tissue characterization of coronary plaque by IVUS Matsuzaki M, Yamaguchi University Graduate School of Medicine, Japan Current remarkable advances in understanding of the pathophysiology of atherosclerosis are now greatly pushing us to get interested in the new imaging field, “Plaque imaging.” Intravascular ultrasound imaging (IVUS) may be one of the promising modalities for coronary plaque imaging. There might be two kinds of approach using intravascular ultrasound (IVUS) to detect a vulnerable plaque. One approach is to develop a color-coded IVUS imaging which can visually reveal a