Lesion isolation by circumferential submucosal incision prior to endoscopic mucosal resection (CSI-EMR) substantially improves en bloc resection rates for 40-mm colonic lesions.
ABSTRACT En bloc resection is preferred for colonic laterally spreading tumors, but is limited to 20 mm with endoscopic mucosal resection (EMR) using normal saline submucosal injection. Our aims were to compare the efficacy and safety of circumferential submucosal incision prior to EMR (CSI-EMR) versus conventional EMR for en bloc resection of artificial lesions 40 x 40 mm in size using submucosal injection of succinylated gelatin in a porcine colon model.
Two areas of normal rectosigmoid mucosa measuring 40 x 40 mm were marked with soft coagulation for en bloc resection in each of 10 pigs. By alternate allocation, one was removed with conventional snare-based EMR following submucosal injection of succinylated gelatin. The other was circumferentially incised using an insulated-tip knife, followed by submucosal succinylated gelatin injection followed by EMR of the isolated area. All procedures were performed by a single endoscopist with significant experience of EMR but none of endoscopic submucosal dissection (ESD). Euthanasia and colectomy were performed on day 10. Specimens and ex vivo colon resection sites were examined by a specialist gastrointestinal histopathologist blinded to the technique used.
En bloc excision rates were 70 % for CSI-EMR vs. 0 % for conventional EMR ( P = 0.016). The median number of resections was 1 (interquartile range, IQR: 1-2) for CSI-EMR vs. 4 (3 - 6) for EMR ( P < 0.001). Mean specimen dimensions were 50 x 43 mm for CSI-EMR vs. 37 x 32 mm for EMR ( P = 0.001). Overall procedure duration (mean +/- SD) was 30.3 +/- 19.8 minutes for CSI-EMR vs. 12.4 +/- 6.8 minutes ( P = 0.003) for EMR. The mean duration of the final 5 CSI-EMRs was 17 minutes, with a statistically significant learning effect R = -0.7, P = 0.025. No perforations or bleeding occurred. All animals were euthanased on day 10. Histologically, CSI-EMR resulted in larger specimens and deeper submucosal resections.
CSI-EMR with submucosal injection of succinylated gelatin is safe and superior to conventional EMR, consistently resulting in en bloc resections larger than 50 x 40 mm. With experience, total procedure duration is comparable.
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ABSTRACT: Succinylated gelatin (SG) is an inexpensive, safe, colloidal solution. It was superior to normal saline (NS) in a porcine colon endoscopic resection (ER) model. Our aim was to compare the efficacy, efficiency, and safety of ER with SG vs. NS. A randomized double-blind trial of submucosal injection with SG vs. NS was conducted for patients undergoing colonoscopy and ER for sessile lesions ≥20 mm in size at an Australian academic hospital endoscopy unit. The primary end point was the "Sydney Resection Quotient" (SRQ), defined as "lesion size in mm divided by the number of pieces to resect." This allows a comparison of technical outcomes for lesions of various sizes. A large lesion removed in fewer pieces gives a greater value. Eighty patients (45 men, mean age 69) with lesions sized 20-100 mm were randomized. A total of 41 SG subjects were well matched to 39 NS subjects, with median (interquartile range) lesion size 40 mm (25-45) vs. 35 mm (30-50), respectively (P=0.382). Complete single-session lesion excision was 90% in both groups. There were no adverse events attributable to SG. The SRQ (median (interquartile range)) was SG 10.0 (7.5-20.0) vs. NS 5.9 (4.4-11.7), P=0.004. Other end points (median (interquartile range)) included fewer resections per lesion in the SG group: 3.0 (1.0-6.0) vs. NS 5.5 (3.0-10.0), P=0.028; fewer injections per lesion with SG: 2.0 (1.0-3.0) vs. NS 3.0 (2.0-11.0), P=0.002; lower injection volume: 14.5 ml (8.5-23.0) vs. NS 20.0 ml (16.0-46.0), P=0.009; and shorter procedure duration with SG: 12.0 min (8.0-28.0) vs. NS 24.5 min (15.0-36.0), P=0.006. SG significantly improves SRQ by almost halving the number of resections for piecemeal ER. SG also safely halves procedure duration.The American Journal of Gastroenterology 11/2010; 105(11):2375-82. · 7.55 Impact Factor
Conference Proceeding: Plasmonic nanophotonics: coupling light to nanoscale via plasmons[show abstract] [hide abstract]
ABSTRACT: An incompatibility between light wavelength at the microscale and devices at the nanoscale can be addressed with plasmonic nanostructures. Plasmonic nanophotonics promises to create new prospects for sensing molecules and guiding light on the nanoscale.Quantum Electronics and Laser Science Conference, 2005. QELS '05; 06/2005
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ABSTRACT: Polypectomy of colonic polyps has been shown to reduce the risk of colon cancer development and is considered a fundamental skill for all endoscopists who perform colonoscopy. A variety of polypectomy techniques and devices are available, and their use can vary greatly based on local availability and preferences. In general, cold forceps and cold snare have been the polypectomy methods of choice for smaller polyps, and hot snare has been the method of choice for larger polyps. The use of hot forceps has mostly fallen out of favor. Polypectomy for difficult to remove polyps may require the use of special devices and advanced techniques and has continued to evolve. As a result, the vast majority of polyps today can be removed endoscopically. Since electrocautery is frequently used for polypectomy, endoscopists should be thoroughly familiar with the basic principles of electrosurgery as it pertains to polypectomy. Tattooing of a polypectomy site is an important adjunct to polypectomy and can greatly facilitate future surgery or endoscopic surveillance. The two most common post-polypectomy complications are bleeding and perforation. Their incidence can be decreased with the use of meticulous polypectomy techniques and the application of some prophylactic maneuvers. This review will examine the technique of polypectomy and its complications from the perspective of the practicing gastroenterologist.World Journal of Gastroenterology. 01/2010;