Salem Omar
University of Malaya
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Gastrointestinal Endoscopy | 2004
Stefan Seewald; Boris Brand; Stefan Groth; Salem Omar; Gerardo Mendoza; Uwe Seitz; Ichiro Yasuda; He Xikun; Vo Chieu Nam; Hong Xu; Frank Thonke; Nib Soehendra
BACKGROUND The treatment of pancreatic fistula can be difficult. A novel endoscopic approach to sealing pancreatic fistulas by using N-butyl-2-cyanoacrylate is described. METHODS Twelve patients with pancreatic fistulas underwent endoscopic injection of N-butyl-2-cyanoacrylate into the fistulous tract, in addition to endoscopic drainage. RESULTS Fistulas were closed successfully in 8 of 12 patients. A single treatment session was successful in 7 patients; a second session was required in one patient. In two patients, closure was temporary, and, in one patient, the treatment failed. One patient died 24 hours after treatment. He developed a pulmonary thromboembolism from a left popliteal vein thrombosis and died from complications of surgical thromboembolectomy. At autopsy, a pulmonary embolus was found, but there was no evidence of N-butyl-2-cyanoacrylate in the lungs. No procedure-related complication occurred over a median follow-up of 20.7 months (range 9-51 months). CONCLUSIONS In this preliminary study, occlusion of pancreatic fistulas by using N-butyl-2-cyanoacrylate glue was safe and effective, and obviated the need for surgery in a substantial proportion of patients. Further studies of the use of N-butyl-2-cyanoacrylate for closure of pancreatic fistula are warranted.
Journal of Gastroenterology | 2006
Yujiro Uchiyama; Hiroo Imazu; Hiroshi Kakutani; Shoryoku Hino; Kazuki Sumiyama; Akira Kuramochi; Shintaro Tsukinaga; Kazuhiro Matsunaga; Takashi Nakayoshi; Kenichi Goda; Shoichi Saito; Mitsuru Kaise; Muneo Kawamuara; Salem Omar; Hisao Tajiri
BackgroundA newly developed narrow-band imaging (NBI) system, which uses modified optical filters, can yield clear images of microvessels and surface structure in gastric and colonic diseases. In the present study, we investigated the ability of magnifying endoscopy with NBI (MENBI) to diagnose and differentiate between benign and malignant ampullary tumors.MethodsFourteen patients, whose ampullas were noted to be significantly enlarged or protruding with conventional endoscopy, were enrolled in the study. Specimens, which were obtained by forceps biopsy, endoscopic papillectomy, and/or surgery, were retrieved for histopathological examination. The correlation between MENBI images and histopathological findings was investigated. MENBI findings were classified as I, oval-shaped villi; II, pinecone/leaf-shaped villi; or III, irregular/nonstructured. In addition, tortuous, dilated, and network-like vessels noted on the ampullary lesions with MENBI were defined as abnormal vessels.ResultsIn 6 of 14 patients, the ampullary changes were proven to be inflammatory in forceps biopsy specimens, without any evidence of malignancy after more than 1 year of follow-up. In five patients, ampullary lesions were treated by endoscopic papillectomy, and in three, by pancreatoduodenectomy. All adenomas and adenocarcinomas had type II and/or type III surface structures, and patients whose ampulla had a type I surface structure had only inflammatory or hyperplastic changes. In addition, abnormal vessels were seen only in adenocarcinomas and never in adenomas.ConclusionsMENBI has the ability and potential to predict histological characteristics of ampullary lesions.
Scandinavian Journal of Gastroenterology | 2010
Hiroo Imazu; Yujiro Uchiyama; Kazuhiro Matsunaga; Keiichi Ikeda; Hiroshi Kakutani; Yoshihiro Sasaki; Kazuki Sumiyama; Tiing Leong Ang; Salem Omar; Hisao Tajiri
Abstract Objective. Sonazoid is a new second-generation microbubble contrast for ultrasonography. In this pilot study, the diagnostic role of contrast-enhanced harmonic imaging endoscopic ultrasonography (CH-EUS) with Sonazoid was prospectively evaluated in preoperative T-staging of pancreaticobiliary malignancies. Patients and methods. Patients with suspected pancreaticobiliary malignancies underwent CH-EUS by a single examiner. After the lesions were observed carefully with conventional harmonic imaging EUS (H-EUS), CH-EUS was performed with intravenous injection of Sonazoid. A reviewer who was blinded reviewed the recordings of H-EUS and CH-EUS and assessed the T-staging. The accuracy of H-EUS and CH-EUS for T-staging was compared to the results of surgical histopathology in patients who underwent surgery. Result. Twenty-six patients underwent surgical resection and could be included in the study. The final diagnosis were pancreatic cancer in 11, bile duct cancer in 7, gallbladder cancer in 4 and ampullary cancer in 4. The overall accuracy of H-EUS and CH-EUS for T-staging were 69.2 (18/26) and 92.4% (24/26), respectively (p < 0.05). There were disagreement in six cases between H-EUS and CH-EUS. CH-EUS staged correctly in all of these six cases, whereas H-EUS misdiagnosed the depth of invasion in one case of gallbladder cancer and one case of ampullary cancer, and invasion of portal vein in two cases of pancreatic cancer and two cases of bile duct cancer. Conclusion. The depth of invasion of biliary cancer and vascular invasion of pancreatic and biliary cancer could be demonstrated more clearly with CH-EUS compared to H-EUS. CH-EUS has the potential to improve the diagnostic accuracy of preoperative T-staging of pancreaticobiliary malignancies.
Gastroenterology Research and Practice | 2009
Hiroo Imazu; Yujiro Uchiyama; Hiroshi Kakutani; Keiichi Ikeda; Kazuki Sumiyama; Mitsuru Kaise; Salem Omar; Tiing Leong Ang; Hisao Tajiri
Background and Aims. There are limited data on the differences in diagnostic yield between 25-gauge and 22-gauge EUS-FNA needles. This prospective study compared the difference in diagnostic yield between a 22-gauge and a 25-gauge needle when performing EUS-FNA. Methods. Forty-three patients with intraluminal or extraluminal mass lesions and/or lymphadenopathy were enrolled prospectively. EUS-FNA was performed for each mass lesion using both 25- and 22-gauge needles. The differences in accuracy rate, scoring of needle visibility, ease of puncture and quantity of obtained specimen were evaluated. Results. The overall accuracy of 22- and 25-gauge needle was similar at 81% and 76% respectively (N.S). Likewise the visibility scores of both needles were also similar. Overall the quantity of specimen obtained higher with the 22-gauge needle (score: 1.64 vs. P < .001). However the 25-gauge needle was significantly superior to the 22-gauge needle in terms of ease of puncture (score: 1.9 vs. 1.29, P < .001) and in the quantity of specimen in the context of pancreatic mass EUS-FNA (score: 1.8 vs. 1.58, P < .05). Conclusion. The 22-gauge and 25-gauge needles have similar overall diagnostic yield. The 25-gauge needle appeared superior in the subset of patients with hard lesions and pancreatic masses.
Scandinavian Journal of Gastroenterology | 2012
Hiroo Imazu; Keisuke Kanazawa; Naoki Mori; Keiichi Ikeda; Hiroshi Kakutani; Kazuki Sumiyama; Shoryoku Hino; Tiing Leong Ang; Salem Omar; Hisao Tajiri
Abstract Objective. Autoimmune pancreatitis (AIP) is often misdiagnosed as pancreatic carcinoma (PC) despite recent advances in imaging tests. The aim of the study was to evaluate whether the quantitative perfusion analysis using software “Time intensity curve” with contrast-enhanced harmonic EUS (CH-EUS) facilitate the differentiation of AIP from PC. Methods. Consecutive patients with focal AIP and pancreatic carcinoma who underwent CH-EUS from January 2009 to September 2010 were analyzed. CH-EUS was performed with intravenous administration of an ultrasonographic contrast (Sonazoid) and electronic radial echoendoscope. The graph of time intensity curve (TIC) for pancreatic mass was generated to depict the changes in signal intensity over time within the region of interest (ROI). ROI was placed to cover an area with a pancreatic mass lesion. Based on the analysis of TIC, base intensity before injection (BI), peak intensity (PI), time to peak, and maximum intensity gain (MIG: PI-BI) were calculated. Results. Eight patients with focal AIP and twenty-two patients with PC were evaluated by TIC. PI and MIG of mass lesion of AIP were significantly higher than that of PC (21.4 dB vs. 9.6 dB, 17.5 vs. 6.6). Receiver operating characteristics analysis yielded an optimal MIG cutoff value of 12.5 with high sensitivity and specificity. Conclusion. Pancreatic mass lesions of AIP and PC exhibited markedly different patterns with the TIC. This novel diagnostic modality using TIC generated by CH-EUS might offer an opportunity to improve accuracy in the differential diagnosis between pancreatic mass lesion of AIP and PC.
Gastrointestinal Endoscopy | 2005
Stefan Seewald; Hiroo Imazu; Salem Omar; Stefan Groth; Uwe Seitz; Boris Brand; Yan Zhong; Sanjay Sikka; Frank Thonke; Nib Soehendra
macroscopic type; as the polyp grows larger and becomes semipedunculated or pedunculated, adenomatous or dysplastic foci appear first, followed by the cancerous lesion. Most adenocarcinomas found within HPs are well differentiated. The occurrence of poorly differentiated adenocarcinoma in an HP is rare. The typical hyperplastic morphology of HP, characterized by ‘‘sawtooth’’ glands and no detectable dysplasia, usually is seen predominantly at the surface. Therefore, biopsy specimens from these polyps may not reveal underlying adenomatous tissue or cancer. The association of cancer and HP is not as clearly established as is the case with adenoma. Nevertheless, we believe and recommend, on the basis of available data that demonstrate that most cases of carcinoma in HP occur in larger polyps, that all gastric HPs larger than 1 cm be resected endoscopically in toto.
Endoscopy | 2009
Stefan Seewald; Tiing Leong Ang; Karl C. Yu Kim Teng; Stefan Groth; Zhong Y; H. Richter; Hiroo Imazu; Salem Omar; L. Polese; U. Seitz; P. Bertschinger; J. Altorfer; Nib Soehendra
Traditionally abdominal abscesses have been treated with either surgical or radiologically guided percutaneous drainage. Surgical drainage procedures may be associated with considerable morbidity and mortality, and serious complications may also arise from percutaneous drainage. Endoscopic ultrasound (EUS)-guided drainage of well-demarcated abdominal abscesses, with adjunctive endoscopic debridement in the presence of solid necrotic debris, has been shown to be feasible and safe. This multicenter review summarizes the current status of the EUS-guided approach, describes the available and emerging techniques, and highlights the indications, limitations, and safety issues.
Journal of Gastroenterology and Hepatology | 2007
Isao Odagi; Tomohiro Kato; Hiroo Imazu; Mitsuru Kaise; Salem Omar; Hisao Tajiri
Background and Aim: Endoscopy is an important clinical tool for the diagnosis and treatment of gastrointestinal disorders. However, biopsy tissue is still required in many cases to obtain a definitive histopathological diagnosis. The aim of this study was to evaluate confocal endomicroscopy (CEM) as a tool for conducting virtual biopsies of the colon by comparing CEM images with biopsy samples from normal colon.
Journal of Gastroenterology and Hepatology | 2011
Lee Guan Lim; Takao Itoi; Wee Chian Lim; Steven Mesenas; Dong Wan Seo; Jonard Tan; Hsiu Po Wang; Thawatchai Akaraviputh; Sandeep Lakhtakia; Salem Omar; Thawee Rantachu; Sharmila Sachitanandan; Kenjiro Yasuda; Shyam Varadarajulu; Jennie Wong; Vinay Dhir; Khek Yu Ho
Endoscopic ultrasound (EUS) and EUS‐guided fine‐needle aspiration (EUS‐FNA) play increasingly prominent roles in the diagnosis and management of pancreatic cysts. The Asian Consortium of Endoscopic Ultrasound was recently formed to conduct collaborative research in this area. This is a review of literature on true pancreatic cysts. Due to the lack of systematic studies, there are no robust data on the true incidence of pancreatic cystic lesions in Asia and any change in over the recent decades. Certain EUS morphological features have been used to predict particular types of pancreatic cysts. Pancreatic cyst fluid viscosity, cytology, pancreatic enzymes, and tumor markers, in particular carcinoembryonic antigen, can aid in the diagnosis of pancreatic cysts. Hemorrhage and infection are the most common complications of EUS‐FNA of pancreatic cysts. Pancreatic cysts can either be observed or resected depending on the benign or malignant nature, or malignant potential of the lesions. Guidelines from an international consensus did not require positive cytological findings to be present in their recommendation for resection, which included all mucinous cystic neoplasms, all main‐duct intraductal papillary mucinous neoplasms (IPMN), all mixed IPMN, symptomatic side‐branch IPMN, and side‐branch IPMN larger than 3 cm. In patients with poor surgical risks, EUS‐guided cyst ablation of mucinous pancreatic cysts is an alternative. As long‐term prospective data on pancreatic cysts are still not available in Asia, management strategies are largely based on risk stratification by surgical risk and malignant potential. Gene expression profiling of pancreatic cyst fluid and confocal laser endomicroscopic examination of pancreatic cysts are novel techniques currently being studied.
Endoscopy | 2012
Hiroo Imazu; Keisuke Kanazawa; Keiichi Ikeda; Hiroshi Kakutani; Kazuki Sumiyama; Tiing Leong Ang; Salem Omar; Hisao Tajiri
A novel multibending backward-oblique viewing duodenoscope was developed to overcome the difficult technical aspect of deep cannulation into the bile duct during endoscopic retrograde cholangiopancreatography (ERCP). The aim of the present study was to evaluate the initial experience of a novel multibending backward-oblique viewing duodenoscope (M-D scope) for ERCP. This was a retrospective review of 23 patients with native papilla who received biliary ERCP with the M-D scope between April and December 2010. The procedures were performed by two well-experienced endoscopists. In all patients, biliary cannulation and therapeutic procedure were successfully completed. In two patients with Billroth I gastrectomy, ERCP were initially attempted with a conventional single-bending duodenoscope, but biliary cannulations were unsuccessful. However, with the use of the M-D scope, biliary cannulation and therapeutic procedures were successfully completed. A novel multibending backward-oblique viewing duodenoscope is safe and feasible for therapeutic and diagnostic ERCP.