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Abstracts E/A ratio ⬎ 1.5 and DT ⬍ 140 ms indicate increased filling pressures. In patients with normal LV ejection fraction (⬎40%), E/E' is the best and easiest parameter to estimate filling pressure; PCWP ⬎ 20 mm Hg if E/E' ⬎ 15 and normal PCWP if E/E' ⬍ 10. In case of 10 ⬍ E/E' ⬍ 15, pulmonary vein, flow duration and Valsalva maneuver can help estimate PCWP. In some patients, PCWP is normal at rest but increases with exertion causing exertional dyspnea. It appears feasible and reliable to estimate PCWP with exercise by recording mitral inflow and annulus velocity (1,2). Normal population with normal diastolic function (hence, normal myocardial relaxation) rarely increases filling pressure with exercise. It seems that diastolic dysfunction (or impaired myocardial relaxation) is a prerequisite for developing exercise-induced high filling pressure. These patients increase cardiac output at the expense of increased filling pressure. In this situation, mitral E velocity increases while annulus E' velocity does not increase as much, or at all resulting in an increase in E/E' ratio. In our initial experience, there are three different groups of patients: (1) normal filling pressure at rest and exercise, (2) normal filling pressure at rest (usually relaxation abnormality) and increased filling pressure with exercise and (3) increased filling pressure at rest and exercise. Exercise duration was significantly shorter for both groups 2 and 3 (seven min) compared to group 1 (10 min). Another observation was that a change in mitral inflow velocity lasts several minutes after termination of exercise when filling pressure is elevated with exercise. Therefore, assessment of both regional wall motion abnormality (immediately after exercise) and diastolic filling pressure (within three minutes of exercise or when E and A velocities are not fused) is possible during exercise echocardiography. We have extended our work by performing simultaneous cardiac catheterization and Doppler echocardiography at rest and with exercise. There was a good correlation between PCWP and E/E’ at rest and with exercise. E/E' ⬎ 15 was reliable in estimating PCWP of greater than 20 mm Hg. Marwick and his colleagues have validated our correlation data in their study with simultaneous invasive measurement of PCWP and E/E'. REFERENCES: (1) Ha J, Lulic F, Bailey K, et al. Effects of treadmill exercise on mitral inflow and annular velocities in healthy adults. Am J Cardiol 2003;91:114-115. (2) Ha J, Oh J, Pellikka P, et al. Diastolic stress echocardiography: a novel invasive diagnostic test for diastolic dysfunction using supine bicycle exercise Doppler echocardiography. J Am Soc Echocardiogr 2005;18:63-68.

ENDOSCOPIC ULTRASOUND 1032 Standard EUS techniques for the gastrointestinal tract lesion using radial and linear models Moon J-S, Lee J-W, Inje University Seoul Paik Hospital, Korea Combining high frequency ultrasound (US) probes with endoscopes make high detail US images of the gastrointestinal tract and structure in the near field. There are three types of EUS (radial, linear and miniprobe through the scope). For EUS examination, the transducer is advanced to the lesion with the endoscopic control. The only source of orientation is US image and stationary anatomic landmark is essential. Gastrointestinal (GI) wall exhibits five alternating hyperechoic and hypoechoic layers denote mucosa, muscularis mucosa, submucosa, propria muscle and subserosa with serosa. We can observe the origin of mass or the depth of the GI tumor by EUS. In using radial model in the stomach, the tip of echoendoscope is advanced to the prepyloric antrum. The balloon on the distal end is filled with water, distracting gas and instillation of water in the stomach improve visualization of US. Scanning is performed slowly withdrawing the instrument under display image control. Anatomic landmarks in the stomach are the liver, pancreas, spleen, gallbladder and left kidney. Major vessels are also

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important landmark to find organs e.g., splenic vein for pancreas. In the esophagus, the echoendoscope is retracted continuously. EUS in thorax is useful for evaluating the esophagus or the mediastinum. Before starting EUS examination in the esophagus, we should determine the exact level and location of the lesion by conventional endoscopy. The echoendoscopic landmarks of the periesophageal regions are the descending aorta, aortic arch, spine and the left atrium. After the tip of the echoendoscope is just superior to the cardia, IVC and right atrium appears. The descending aorta locates between right atrium and spine. Retraction reveals the left atrium. Subcarinal space is located proximally to the left atrium. More proximally, two mainstem bronchi appear as strong echoes. Further retraction reveals broad hypoechoic aortic arch. The aortopulmonary window is just caudal to the aortic arch. Above the aortic arch are the left subclavian artery and the left carotid artery. Linear echoendoscopic examination from the stomach encompasses gastrointestinal structure and many adjacent organs. Main landmark of the linear echoendoscope in the stomach is liver, pancreas, gallbladder, CBD, portal venous system, spleen, celiac trunk and SMA. Celiac trunk and superior mesenteric artery inferiorly are originating off the anterior wall of abdominal aorta. Celiac artery bifurcates into the splenic and hepatic artery. In thorax, main landmark is aorta. Pulling from the descending aorta to the aortic arch, visible structures are the tracheobronchial tree, pulmonary vein, pulmonary artery, azygous vein arch, left atrium and esophagus. Rotating through the aortic arch, the pulmonary artery is just distal to the aortic arch. The aortopulmonary window is the space between the aortic arch and pulmonary artery. Subclavian artery rises off the aorta. Subcarinal space can be found if pulled slightly when the left atrium is observed. In colon, we can observe endosonographic evaluation of the bowel up to the ileocecal valve. Colonic wall has five-layer architecture. The urinary bladder, prostate, uterus and vagina from the rectum are landmarks for orientation. 1033 Standard EUS techniques for bilio-pancreatic lesion using radial and linear models Yasuda K, Kyoto Second Red Cross Hospital, Japan Although endoscopic ultrasonography has been developed as an indispensable imaging technique for the diagnosis of digestive diseases, EUS procedure for bilio-pancreatic system is sometimes difficult. In order to solve this problem and to recognize the EUS study as widespread method, standardization of EUS scanning is important. EUS instruments can be divided into two models; one is radial model, which is used for imaging diagnostic tool, and the other is convex model for EUS guided FNA (fine needle aspiration techniques). EUS study in bilio-pancreatic lesion is recommended to learn how to operate and how to analyze the images, as we can not see this field endoscopically. Another difficulty is the difference of scanning plane. As the scanning plane is vertical to the EUS scope in radial model, on the other hand, parallel to the scope in convex model, EUS images by radial model requires the training. That means we have to learn the scanning position and obtained images in radial model, but we have to know the scanning position in convex model as the image is same with those of conventional ultrasound scanning. EUS study is started facing the patient with left lateral position. For the EUS delineation of bilio-pancreatic tract by radial model, there are three basic scanning positions. One is through the gastric scanning to demonstrate pancreatic body and tail indexing splenic artery and vein, left kidney, superior mesenteric artery (SMA), celiac artery and aorta. For this scanning, inserting the scope up to the gastric antrum and aspirating the air in the stomach, EUS scanning is started inflating the balloon and withdrawing the scope. The other is through the duodenal bulb and second portion to demonstrate pancreas head and biliary tract including gall bladder and papilla of Vater

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indexing portal and splenic vein, aorta, inferior vena cava (IVC) and SMA. In the use of convex model, it is recommended to demonstrate bilio-pancreatic tract though the stomach and duodenum. Premedication and patient’s position are same with those of radial model. Through the gastric wall, aorta, SMA and splenic artery and vein are indices to observe the pancreas body and tail. EUS images of portal vein IVC are indices for demonstrating the biliary tract and head of the pancreas trough the duodenal wall. Manipulation of EUS scope is different in radial and convex models. Standardization of EUS scan is important both in the radial and convex models of ultrasound endoscope to achieve the aim of EUS procedures. 1034 Role of intraductal ultrasound (IDUS) for bilio-pancreatic lesion Shim CS, Soonchunhyang University Hospital, Korea Introduction: Endoscopic ultrasonography (EUS) represents a major advance in endoscopic imaging. Usefulness and effectiveness of EUS have been established during the past few years. Recently, developed ultrasonic miniprobes can be passed through the working channel of endoscopes to provide high-frequency ultrasound images. Catheterprobes with diameters of 3 mm or less provide a means for endoluminal US imaging in conjunction with diagnostic endoscopy. The ultrasonic miniprobe is an ideal instrument for insertion into fluid-filled tubular structures such as the bile duct system, which are only slightly larger in diameter than the miniprobe itself. In some cases, however, it is very difficult to insert the miniature ultrasonic probe into the bile duct. Recently, wire-guided IDUS was developed to overcome this problem of conventional ultrasonic probe. Materials and Procedures: To date, two principal miniprobe systems exist: electronic phased array and mechanical radial sector scan system. However, at present mechanical probes are commonly used as they outperform electronic probes in terms of image quality, depth of penetration, and durability. Because their diameter is only about 2 mm, these ultrasonic probes may be passed through the biopsy channel of routinely used duodenoscopes. The small diameter enables IDUS of the biliopancreatic duct after transpapillary or transhepatic insertion. The probe tip can be localized fluoroscopically. Images are continuously recorded on videotape upon retraction of the probe. Clinical Applications: These probes have been adapted for imaging of the biliopancreatic ductal system. During ERCP ultrasonic miniprobe insertion into the bile duct or pancreatic duct system is easier, quicker and safer to perform and thus IDUS might add valuable information regarding the periductular tissue to diagnostic and therapeutic ERCP. IDUS offers high-quality cross-sectional images of the bile duct, pancreatic duct and nearby regions. Possible clinical indications for IDUS of the biliopancreatic ductal systems are choledocholithasis, characterization of biliopancreatic strictures, locoregional tumor staging and localization of islet cell tumors negative on endoscopic ultrasonography. One of the most promising applications of IDUS imaging is the staging of biliary cancers. The bile duct and adjacent vessels are visualized in transverse section. Hepatic artery invasions and portal vein invasions can thus be demonstrated. IDUS has also been shown to be clinically useful in evaluating the extent of cancers of the major duodenal papilla. In fact, recent study found IDUS to be superior to EUS in staging polypoid tumors of the major papilla. Complications and Safety: In transpapillary bile duct scanning, mild acute pancreatitis occurs rarely, and resolves with conservative management with fasting and the administration of protease inhibitor. No other complications have been observed so far. In transhepatic bile duct scanning, no complication due to insertion of the ultrasonic probe has been reported. Conclusion: IDUS is very useful diagnostic tool for evaluating and assessing various biliopancreatic diseases.

Volume 32, Number 5S, 2006 1035 Role of diagnostic EUS-guided FNA Kim J-O, Cho YD, Soonchunhyang University Hospital, Korea EUS were initially developed to improve better ultrasound imaging of the pancreas; it was widely used for the differential diagnosis of the gastrointestinal and biliopancreatic lesions, such as to stage gastrointestinal/biliopancreatic cancers and to evaluate tumors arising from the gut wall. But EUS as an imaging modality has limited specificity, when attempting to distinguish benign from malignant lymph nodes, pancreatic masses, giant gastric folds and malignant gastrointestinal tumors. Although certain features may suggest malignancy, tissue sampling is still required to confirm the diagnosis. EUS-guided FNA is limited to areas in which the EUS can visualize the target lesion and where the needle has a clear pathway without intervening vessels or cancer. The clinical utility of EUS-guided FNA appears to be greatest in the diagnosis and staging of pancreatic cancer and in the nodal staging of gastrointestinal, pancreatic and pulmonary malignancies. Every lesion imaged by EUS does not need to be sampled by FNA. The additional clinical impact of EUS guided puncture should be considered prior to every FNA. A fundamental principle in establishing indications for EUS-guided FNA is a determination as to whether or not the information obtained has the potential to affect patient management. If the result of the FNA cannot affect patient management the procedure should not be performed. The current common and possible indication where EUS guide FNA is important to adjunct EUS are; unresectable pancreatic mass; undiagnosed pancreatic mass in which FNA may be performed to try to differentiate chronic pancreatitis from pancreatic cancer; suspicious lymph nodes associated with esophageal cancer; posterior mediastinal LN associated with nonsmall cell lung cancer; undiagnosed posterior mediastinal mass in which the differential could include lymphoma, small cell lung cancer and enlarged lymph nodes from mediastinal infections, and others; in a patient with known or suspected cancer, EUS detects celiac LN, liver mass and ascites. EUS FNA may be useful for the early diagnosis of malignant ascites; pelvic mass adjacent to rectum/distal sigmoid; submucosal tumors if FNA may change patient management; recurrent cancer in or adjacent to an anastomosis not diagnosed by conventional endoscopic biopsy (rectal, esophageal and gastric cancer); lesions suspected of malignancy outlined by EUS and not finally diagnosed by other modalities (liver, spleen, left adrenal). However there are some problems remaining about the false negative cases, histological diagnosis from the very tiny materials and the risk of disseminating the malignant cells by the procedure. For the better result of EUS-guide FNA, multidisciplinary team approach, to provide detailed clinical information to the cytopathologist, extra passes for special studies are needed. Prior to perform the EUS-guided FNA endosonographer have to think of the clinical impact and then push that needle. 1036 Role of therapeutic EUS-guided FNA Irisawa A, Takagi T, Hikichi T, Fukushima Medical University School of Medicine, Japan The development of curved linear-array endoscopic ultrasound (EUS), which allow real-time visualization of a needle axis has overcome the inability of radial EUS concerning with tissue sampling, and moreover has permitted various EUS-guided interventions. Therefore, interventional EUS is applied not only for definite diagnosis but also EUSguided therapy. To date, there are many reports of therapeutic interventional EUS including experimental model, such as EUS-guided fine needle injection (FNI) (e.g., celiac plexus neurolysis, anti-cancer therapy), ablation (e.g., using radiofrequency), stent-indwelling (e.g., pancreatic pseudocysts drainage via gastrointestinal wall) and suturing.