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Endoscopic Ultrasound (EUS) Guided Drainage of Pseudocysts: Safer and More Effective Compared to Standard Endoscopic Drainage
Abstracts
W1318 Concentration-Dependent Efficacy of Endoscopic Ultrasound-Guided Ethanol Ablation of Pancreatic Tissue in the Pig Kai Matthes, Mari Mino-Kenudson, Dushyant Sahani, Nagaraj S. Holalkere, William R. Brugge Background: Ethanol is a commonly available agent and has been used to successfully and safely ablate cystic lesions. The aim of this study was to determine the local and systemic long-term effect of EUS-guided injection of ethanol into the pancreas of pigs using 2 ml of ethanol, in increasing concentration of 0% to 100%, diluted with normal saline. Methods: Six pigs were sedated by general anesthesia and ethanol was injected under EUS-guidance with a 22-gauge needle into the tail of the pancreas. The endpoints of this study were gross and microscopic evidence of inflammation of the pancreas and clinical tolerance. The animals were observed by determining the blood levels of amylase and lipase and by an upper abdominal CT scan. Results: Six Yorkshire breed pigs were used for this study. The animals were monitored for 7 days after the injection. CT scanning demonstrated a localized site of non-perfused pancreatic tissue measuring on average 19.4 ( G10.5) mm in the animals that underwent an injection 40%, 60%, 80% and 100% of ethanol. By CT, there was no evidence of peri-pancreatic fat necrosis. At sacrifice, no gross lesion could be identified in the pancreatic tail of the animals that received normal saline or 20% ethanol. The other animals displayed a visible necrotic area in the tail of the pancreas (figure 1). By histology, the average maximal diameter of the lesions was 20.8 ( G4.3) mm. The diameter of tissue necrosis correlated with the concentration of injected ethanol. Clinically, the animals appeared to tolerate the procedure well. Blood levels of amylase and lipase were within normal limits. Conclusions: The EUS-guided injection of ethanol into the pig pancreas resulted in localized tissue necrosis. This technique is a potential minimally invasive local treatment option for pancreatic neuroendocrine tumors.
imaged. To create an animal model of pancreatic microvascular disruption, 0.5 mL of 50% ethanol plus purified carbon particle solution (GI SpotÒ) was injected with an OlympusÒ 22 g EUS-FNA needle into the body of the pancreas under EUS guidance. 24-48 hours post ethanol-injection, the pancreas was re-evaluated with EUS and CE-EUS. Standard and CE-EUS imaging of the pancreas were compared. Post-mortem examination of the pancreas was performed. Results: With conventional EUS, there was minimal color flow within the pancreatic parenchyma. Within 30 seconds of injection of microspheres, the microvasculature of the pancreas was well visualized with increased color flow. The echogenic microspheres were also well seen in the peri-pancreatic vessels. The mean duration CE-EUS visualization was 2.29 minutes. Standard EUS imaging showed a subtle 1 cm hypoechoic region in the ethanol-treated area in the body. Color and power doppler EUS of this region did not reveal any signal or blood flow. After microsphere injection, color Doppler EUS revealed marked contrast enhancement of normal pancreatic parenchyma from the ethanol-treated area, which on gross examination corresponded to a discrete necrotic area marked with GI Spot. Conclusions: CE-EUS with microspheres improves EUS visualization of the pancreatic parenchymal microvasculature and delineation of altered vascular perfusion. Use of CE-EUS may aid in the detection of subtle neoplastic pancreatic lesions due to neo-angiogenesis. Current studies investigating the use of CE-EUS in patients with pancreatic disease are ongoing.
W1320 Endoscopic Ultrasound (EUS) Guided Drainage of Pseudocysts: Safer and More Effective Compared to Standard Endoscopic Drainage Jan-Werner Poley, Jelle Haringsma, Sarwa Darwish Murad, Jan Dees, Casper H. J. Van Eijck, Ernst J. Kuipers
Figure 1. Gross findings after EUS-guided ethanol ablation (using 100% ethanol).
W1319 Contrast-Enhanced Endoscopic Ultrasonography (CE-EUS) Improves Visualization of Pancreatic Vasculature Samuel A. Giday, Marcia I. Canto, Priscilla Magno, Jon Buscaglia, John Clarke, Chung-Wang Ko, Lori Wroblewski, Anthony N. Kalloo, Sergey V. Kantsevoy, Sanjay Jagannath EUS may not detect small or infiltrating neoplastic pancreatic lesions. Neovascularization in neoplasms may enable improved visualization with EUS if a contrast agent is used. Lipid microspheres are an established diagnostic tool for increasing contrast of vascular structures in echocardiography. These microspheres increase the reflected ultrasound signals in the microvasculature and improve visualization of perfused tissues. Aim: To evaluate the potential utility of contrast enhanced EUS (CE-EUS) using microspheres in the characterization of pancreatic lesions and delineation of nearby vascular structures in a porcine model. Methods: Three anesthesized 50 kg pigs underwent EUS using an Olympus linear echoendoscope (GF-UCT140) with the Aloka Prosound SSD 5000 EUS processor. The pancreas and adjacent vessels were visualized at 16 Mhz frequency. For optimal visualization of the microspheres, the ultrasound mechanical index was decreased to 0.3. 2 mL of Perflutren lipid microspheres (5 uL/kg) (DefinityÒ) were administered by peripheral IV and the pancreas and peri-pancreatic vessels were re-
AB266 GASTROINTESTINAL ENDOSCOPY Volume 63, No. 5 : 2006
Introduction: Transmural endoscopic drainage of pseudocysts is an accepted alternative for surgical or radiological interventions although no direct comparative studies exist. Endoscopic drainage can be performed with several different techniques that have not directly been compared. Standard drainage techniques rely on bulging of the pseudocyst into the lumen of the stomach or duodenum. After radial EUS, the cyst is punctured and after introduction of a guidewire into the pseudocyst, stents are placed under fluoroscopic control. The recent introduction of therapeutic linear echo-endoscopes has made it possible to perform the entire procedure EUS-guided. It is unknown which method of drainage is most effective and safe, therefore we compared safety and efficacy of both types of procedure. Methods: Patients who underwent pseudocyst or fluid collection drainage since 2003 in our center were identified from a database. Follow up ranged from 3 months to 2 years. All cysts that were considered for drainage were either symptomatic, and/or increasing in diameter during an observation period. Standard cyst drainage was performed by several operators. Since June 2004 all but two drainage procedures were done EUS-guided by a single endoscopist. In these procedures, after EUS guided puncture of the cyst, balloon dilation to 8 mm was performed and up to 3 double pigtail stents were placed. In cases of proven or suspected infection a nasocystic catheter was placed as well. Results: A total of 53 procedures were performed in 49 patients. Standard drainage was performed in 25 procedures (60% of patients male; median age 53 yrs, range 33 - 83); 28 procedures were done EUS-guided (61% male; median age 48 yrs, range 8 - 77). Significantly more patients in the EUS group had abscesses/infected necrosis (10/28; 36% vs. 2/ 25; 8%; p Z 0.016). Successful drainage was significantly higher in the EUS group: 96% (27/28) vs. 56% (14/25); p ! 0.001. On average more stents were placed in the EUS group: median 3 vs. median 1; p ! 0.001. Long-term success rates (defined as disappearance of the cyst without the need for surgical or radiological intervention during long-term follow-up) were also much better in the EUS-group: 81% (22/27) vs. only 42% (10/22); p Z 0.003. In the standard group significantly more complications were seen: 28% (7/25) vs. 7% (2/28); p Z 0.04. No follow-up data were available for 2 patients. Conclusions: EUS guided drainage of pseudocysts is more effective and safer than the standard endoscopic method relying on bulging of the pseudocyst into the lumen. EUS-guided drainage should therefore be the preferred method for treating patients with pancreatic pseudocysts.
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W1318 Concentration-Dependent Efficacy of Endoscopic Ultrasound-Guided Ethanol Ablation of Pancreatic Tissue in the Pig Kai Matthes, Mari Mino-Kenudson, Dushyant Sahani, Nagaraj S. Holalkere, William R. Brugge Background: Ethanol is a commonly available agent and has been used to successfully and safely ablate cystic lesions. The aim of this study was to determine the local and systemic long-term effect of EUS-guided injection of ethanol into the pancreas of pigs using 2 ml of ethanol, in increasing concentration of 0% to 100%, diluted with normal saline. Methods: Six pigs were sedated by general anesthesia and ethanol was injected under EUS-guidance with a 22-gauge needle into the tail of the pancreas. The endpoints of this study were gross and microscopic evidence of inflammation of the pancreas and clinical tolerance. The animals were observed by determining the blood levels of amylase and lipase and by an upper abdominal CT scan. Results: Six Yorkshire breed pigs were used for this study. The animals were monitored for 7 days after the injection. CT scanning demonstrated a localized site of non-perfused pancreatic tissue measuring on average 19.4 ( G10.5) mm in the animals that underwent an injection 40%, 60%, 80% and 100% of ethanol. By CT, there was no evidence of peri-pancreatic fat necrosis. At sacrifice, no gross lesion could be identified in the pancreatic tail of the animals that received normal saline or 20% ethanol. The other animals displayed a visible necrotic area in the tail of the pancreas (figure 1). By histology, the average maximal diameter of the lesions was 20.8 ( G4.3) mm. The diameter of tissue necrosis correlated with the concentration of injected ethanol. Clinically, the animals appeared to tolerate the procedure well. Blood levels of amylase and lipase were within normal limits. Conclusions: The EUS-guided injection of ethanol into the pig pancreas resulted in localized tissue necrosis. This technique is a potential minimally invasive local treatment option for pancreatic neuroendocrine tumors.
imaged. To create an animal model of pancreatic microvascular disruption, 0.5 mL of 50% ethanol plus purified carbon particle solution (GI SpotÒ) was injected with an OlympusÒ 22 g EUS-FNA needle into the body of the pancreas under EUS guidance. 24-48 hours post ethanol-injection, the pancreas was re-evaluated with EUS and CE-EUS. Standard and CE-EUS imaging of the pancreas were compared. Post-mortem examination of the pancreas was performed. Results: With conventional EUS, there was minimal color flow within the pancreatic parenchyma. Within 30 seconds of injection of microspheres, the microvasculature of the pancreas was well visualized with increased color flow. The echogenic microspheres were also well seen in the peri-pancreatic vessels. The mean duration CE-EUS visualization was 2.29 minutes. Standard EUS imaging showed a subtle 1 cm hypoechoic region in the ethanol-treated area in the body. Color and power doppler EUS of this region did not reveal any signal or blood flow. After microsphere injection, color Doppler EUS revealed marked contrast enhancement of normal pancreatic parenchyma from the ethanol-treated area, which on gross examination corresponded to a discrete necrotic area marked with GI Spot. Conclusions: CE-EUS with microspheres improves EUS visualization of the pancreatic parenchymal microvasculature and delineation of altered vascular perfusion. Use of CE-EUS may aid in the detection of subtle neoplastic pancreatic lesions due to neo-angiogenesis. Current studies investigating the use of CE-EUS in patients with pancreatic disease are ongoing.
W1320 Endoscopic Ultrasound (EUS) Guided Drainage of Pseudocysts: Safer and More Effective Compared to Standard Endoscopic Drainage Jan-Werner Poley, Jelle Haringsma, Sarwa Darwish Murad, Jan Dees, Casper H. J. Van Eijck, Ernst J. Kuipers
Figure 1. Gross findings after EUS-guided ethanol ablation (using 100% ethanol).
W1319 Contrast-Enhanced Endoscopic Ultrasonography (CE-EUS) Improves Visualization of Pancreatic Vasculature Samuel A. Giday, Marcia I. Canto, Priscilla Magno, Jon Buscaglia, John Clarke, Chung-Wang Ko, Lori Wroblewski, Anthony N. Kalloo, Sergey V. Kantsevoy, Sanjay Jagannath EUS may not detect small or infiltrating neoplastic pancreatic lesions. Neovascularization in neoplasms may enable improved visualization with EUS if a contrast agent is used. Lipid microspheres are an established diagnostic tool for increasing contrast of vascular structures in echocardiography. These microspheres increase the reflected ultrasound signals in the microvasculature and improve visualization of perfused tissues. Aim: To evaluate the potential utility of contrast enhanced EUS (CE-EUS) using microspheres in the characterization of pancreatic lesions and delineation of nearby vascular structures in a porcine model. Methods: Three anesthesized 50 kg pigs underwent EUS using an Olympus linear echoendoscope (GF-UCT140) with the Aloka Prosound SSD 5000 EUS processor. The pancreas and adjacent vessels were visualized at 16 Mhz frequency. For optimal visualization of the microspheres, the ultrasound mechanical index was decreased to 0.3. 2 mL of Perflutren lipid microspheres (5 uL/kg) (DefinityÒ) were administered by peripheral IV and the pancreas and peri-pancreatic vessels were re-
AB266 GASTROINTESTINAL ENDOSCOPY Volume 63, No. 5 : 2006
Introduction: Transmural endoscopic drainage of pseudocysts is an accepted alternative for surgical or radiological interventions although no direct comparative studies exist. Endoscopic drainage can be performed with several different techniques that have not directly been compared. Standard drainage techniques rely on bulging of the pseudocyst into the lumen of the stomach or duodenum. After radial EUS, the cyst is punctured and after introduction of a guidewire into the pseudocyst, stents are placed under fluoroscopic control. The recent introduction of therapeutic linear echo-endoscopes has made it possible to perform the entire procedure EUS-guided. It is unknown which method of drainage is most effective and safe, therefore we compared safety and efficacy of both types of procedure. Methods: Patients who underwent pseudocyst or fluid collection drainage since 2003 in our center were identified from a database. Follow up ranged from 3 months to 2 years. All cysts that were considered for drainage were either symptomatic, and/or increasing in diameter during an observation period. Standard cyst drainage was performed by several operators. Since June 2004 all but two drainage procedures were done EUS-guided by a single endoscopist. In these procedures, after EUS guided puncture of the cyst, balloon dilation to 8 mm was performed and up to 3 double pigtail stents were placed. In cases of proven or suspected infection a nasocystic catheter was placed as well. Results: A total of 53 procedures were performed in 49 patients. Standard drainage was performed in 25 procedures (60% of patients male; median age 53 yrs, range 33 - 83); 28 procedures were done EUS-guided (61% male; median age 48 yrs, range 8 - 77). Significantly more patients in the EUS group had abscesses/infected necrosis (10/28; 36% vs. 2/ 25; 8%; p Z 0.016). Successful drainage was significantly higher in the EUS group: 96% (27/28) vs. 56% (14/25); p ! 0.001. On average more stents were placed in the EUS group: median 3 vs. median 1; p ! 0.001. Long-term success rates (defined as disappearance of the cyst without the need for surgical or radiological intervention during long-term follow-up) were also much better in the EUS-group: 81% (22/27) vs. only 42% (10/22); p Z 0.003. In the standard group significantly more complications were seen: 28% (7/25) vs. 7% (2/28); p Z 0.04. No follow-up data were available for 2 patients. Conclusions: EUS guided drainage of pseudocysts is more effective and safer than the standard endoscopic method relying on bulging of the pseudocyst into the lumen. EUS-guided drainage should therefore be the preferred method for treating patients with pancreatic pseudocysts.
www.giejournal.org