Objective To study the occurrence of bacteremia and whether washing gastric mucosa with povidone-iodine could reduce its occurrence after endoscopic ultrasonography (EUS)-guided fine needle aspiration (FNA). Methods A total of 20 healthy adult dogs were randomly assigned into experimental group and control group, with 10 in each. The animals in experimental group underwent gastric mucosa washing with 10 ml 0. 5% povidone-iodine solution before FNA, while those in control group with 10ml normal saline. Blood samples were collected for culture before EUS, between EUS and FNA, and 5, 15 and 30 minutes after FNA. Results There were 3 cases of positive bacteremia in experimental group and l in control group,which were not significantly different ( P = 0. 582). Conclusion Pre-washing gastric mucosa with 0. 5% povidone-iodine solution cannot reduce bacterial infection after EUS-guided FNA.

Objective To determine the value of EUS- guided fine needle aspiration biopsy (FNAB)for the diagnosis of submucosal lesions.MethodsWe found 28 patients with upper gastrointestinal tract solid submucosal lesions by endoseopies. EUS was performed to assess the lesions arised from the specific layer of the wall and the lymph node metastasis. After excluding extrinsic normal tissues compressing the gastrointestinaltract, EUS guided FNAB were carried out. Results Among these patients, two were extrinsic normal tissues compressing the gastrointestinal tract and all other 26 patients were examined by EUS guided FNAB. EUS- guided FNAB failed in only 3 patients. Among the other 23 patients, cytology demonstrated malignant tumors in 4 patients(lymphoma, n=2; leiomyosarcoma, n=2) and benign lesions in 19 patients(leiomyoma, n=1;lipoma, n=1 ). The results of EUS-guided FNAB were validated by surgery (n=20), endoscopic treatment (n=1) or clinical follow-up (n=7). Conclusion EUS guided FNAB is a safe and accurate method for di-agnosis of submucosal lesions.

Objective To determine the value of endoscopic ultrasonography (EUS)-guided fine needle aspiration biopsy (FNAB) for differential diagnosis of pancreatic lesions. Methods EUS was performed in 23 patients with pancreatic lesions detected by CT, MRI, or US to assess the shape, size, and position of the lesions and the status of lymph nodes metastasis. After excluding blood vessel between the lesions and the fine needle by EUS, EUS guided FNAB was carried out. Results All patients were performed EUS-guided FNAB and only 2 patients failed. Among the other 21 patients, cytology and pathology demonstrated tumors in 10 patients (pancreatic carcinoma, n=8; pancreatic cystadenoma, n=1; non functional neuroendocrine tumor, n=1). The results of EUS-guided FNAB were evaluated by surgery (n=16), or clinical follow-up (n=7). The sensitivity was 83%, and speciality was 100%, and no complication occurred. Conclusions EUS-guided FNAB is a safe and accurate method for differential diagnosis of pancreatic lesions.

Objective To determine the diagnostic value of endoscopic ultrasound-guided cholangiography(EUSGC)with fine needle puncture .Methods Twenty-six patients with obstructive jaundice failed i n previous endoscopic retrograde cholangiopancreatography(ERCP) and magnetic res onance cholangiopancrcatography(MRCP) or have metallic foreign materials in some where of body. By a linear scanning echoendoscopy in conjunction with a 22-gau ge aspiration needle, transduodenal selective cholangiography was attempted.Results Cholangiography was successfully performed in all patie nts (EUSGC success 100% vs. ERCP 0%). No complications occurred in the patients. In 19 patients, abnormalities were found from EUSGC. Choledocholithiasis have b een confirmed by sphincterotomy(n=5),common bile duct strictures were confirmed by surgical operation(n=11).Three other patients have delayed excretion of co ntract medium.Conclusion EUSGC allows a safe and accurate alternative method for obtaining cholangiography in those patients when ERCP or MRCP failed.

Objective To evaluate the method of endoscopic band ligation in resecting upper gastrointestinal leiomyoma . Methods We selected 59 patients with 64 small upper gastrointestinal tract leiomyo-mas by endoscopy , EUS and EUS guided fine needle aspiration. Of the 64 leiomyomas, their distribution were in esophagus 50, stomach 12 and duodenum 2. When the endoscope with transparent cap was introduced to reach the lesion, it was sucked into the cap, then released the band to ligate it. Two weeks after operation, endoscopic monitoring of the lesion was performed weekly until the complete healing of the wound. Results In the 64 lesions, 50 esophageal and 2 duodenal leiomyomas were thoroughly resected and the mean concrescence time is 3. 1 weeks and 4. 5 weeks respectively. Nine of 12 gastric leiomyomas were resected thoroughly and the other 3 were partially ligated and resulted in incomplete excision with the mean concrescence time of 4. 5weeks. No perforation occurred. Conclusions Endoscopic band ligation is an ideal method in resecting the small upper gastrointestinal leiomyomas.

Objective To investigate the feasibility and safety of endoscopic ultrasonography (EUS) guided interstitial chemotherapy for the pancreas in canine model. Methods A therapeutic 19gauge needle was inserted into the pancreas with EUS guidance,and seeds with sustained release of 5-iluorouracil were implanted into the tissue. After 14 days of clinical observation,the animals were sacrificed and the tissue response to local chemotherapy was examined. Results All the seeds were implanted successfuUy and no migration was observed. Chemotherapy induced tissue fibrous necrosis was localized in the pancreas without significant complications. The apoptotic index of tissue within 1 cm of the seeds increased.Biochemical parameters were normal in all the dogs. Conclusion EUS-guided implantation of seeds is a safe,simple and minimally invasive technique for interstitial chemotherapy in the pancreas.

To evaluate the effect of endoscopic ultrasonography guided celiac plexus neurolysis (EUS CPN) on pain associated with pancreatic carcinoma. Methods EUS CPN was performed to relieve pain in 16 patients with advanced pancreatic carcinoma. By EUS, we used fine needle to puncture at the region of celiac ganglion and inject alcohol. The pain tensions were followed up under visual analogue scale rule at 2 days and weekly thereafter. Results All patients were performed EUS CPN successfully. No serious complications happened. No satisfactory pain control after the first 2 days of EUS CPN.Whereas it was relieved obviously after 7 days and the effects maintain a rather long term. Conclusion EUS CPN is a safe and effective method for releiving the pain in pancreatic carcinoma.

Objective To investigate the differences of EUS images between stromal tumors and leiomyoma in esophagus and cardia. Methods EUS image of 13 cases of stromal tumors and 11 cases of leiomyoma diagnozed immunohistochemically were collected. Information of gray scale including mean value and dissociation of lesions and submucosal layer were analyzed. Gray scale values of lesions were calibrated according to that of the submucosal layer. Results The mean value of corrected gray scale of stromal tumors was 0. 285, which was significantly different from that of leiomyoma (0. 185, P ＜ 0. 05). Dissociation of gray scale of stromal tumors was 8. 14, which was also significantly different from that of leiomyomia (4. 59,P ＜0. 05). Conclusion In esophagus and cardia, stromal tumors exhibits higher and more inhomogeneous ultrasound echo than leiomyoma.

Objective It is difficult to differentiate tumors in upper GI muscularis proporia, such as GI stromal tumors (GISTs) , leiomyomas and schwannomas. We performed EUS guided fine needle aspirations (FNA) and immunohistochemical evaluation of these tumors in upper GI muscularis proporia. Methods We selected 35 Patients with lesions in upper GI muscularis proporia by EGD and EUS. We assessed the shape , size, and position of the lesions and the status of metastasis. After excluding blood vessel between the lesions and the fine needle, EUS FNA were carried out and immunohistochemical staining for CD-117 (c-kit) , CD34 and smooth muscle actin ( SMA) was performed. Results All patients were performed EUS FNA and enough specimens were obtained in 31 patients. The other 4 failed, although we tried it for several times. Among the 31 patients, Cytology and immunohistochemisty demonstrated 21 GISTs and 10 leiomyomas. All the results were evaluated by surgery. The sensitivity is 88. 6% , and the speciality is 100%. No complication occurred. Conclusion EUS-guided FNA and immunohistochemical evaluation is an accurate method for diferential diagnosis of tumors in upper GI muscularis propria.

Objective To evaluate the diagnostic value of endoscopic ultrasonic elastography in lymph node staging of gastrointestinal tumors.Methods Thirty-nine abdominal lymph nodes and 26 mediastinal lymph nodes of 35 patients with gastric cancer or esophageal carcer were examined by endoscopic ultrasonic elastography of five-point elastic score.Lymph node at 1-3 points was regarded as negative(benign),while 4-5 points as positive(malignant).The diagnostic value of EUS elastography was determined by comparing the results with pathological findings.Results Of all the 65 lymph nodes,49 were diagnosed as positive and 16 negative.The sensitivity and specificity of EUSE in the diagnosis of malignant lymph nodes were 91.1%and 60.0%.respectively.Conclusion EUSE is helpful for diagnosis of malignant metastasic lymph nodes.