D.A. Howell
Maine Medical Center
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Featured researches published by D.A. Howell.
Gut | 1998
T.C.K. Tham; David L. Carr-Locke; J. Vandervoort; R.C.K. Wong; D R Lichtenstein; J Van Dam; F Ruymann; S. Chow; John J. Bosco; T. Qaseem; D.A. Howell; Douglas K. Pleskow; W Vannerman; E D Libby
Background—Wallstents (Schneider Stent, Inc., USA) used for the palliation of malignant biliary strictures, although associated with prolonged patency, can occlude. There is no consensus regarding the optimal management of Wallstent occlusion. Aims—To evaluate the efficacy of different endoscopic methods for managing biliary Wallstent occlusion. Methods—A multicentre retrospective study of patients managed for a biliary Wallstent occlusion. Results—Data were available for 38 patients with 44 Wallstent occlusions, all of which had initial endoscopic management. Twenty four patients had died and 14 were alive after a median follow up of 231 (30–1095) days following Wallstent occlusion. Occlusions were managed by insertion of another Wallstent in 19, insertion of a plastic stent in 20, and mechanical cleaning in five. Endoscopic management was successful in 43 (98%). Following management of the occlusion, bilirubin decreased from 6.0 (0.5–34.3) to 2.1 (0.2–27.7) mg/100 ml (p<0.05). No complications occurred. The median duration of second stent patency was 75 days (95% confidence interval 43 to 107) after insertion of another Wallstent, 90 days (71 to 109) after insertion of a plastic stent, and 34 days (30 to 38) after mechanical cleaning (NS). The respective median survivals were 70 days (22–118), 98 days (54–142), and 34 days (30–380) (NS). Incremental cost effective analysis showed that plastic stent insertion is the most cost effective option. Conclusion—Although all three methods are equally effective in managing an occluded Wallstent, the most cost effective method appears to be plastic stent insertion.
Gastrointestinal Endoscopy Clinics of North America | 2003
Richard J. Farrell; D.A. Howell; Douglas K. Pleskow
Known and documented factors attributable to ERCP-related complications include the experience and technique of the endoscopist as well as anatomic and pathologic factors pertaining to the papilla. In an effort to minimize trauma, facilitate deep entry to the biliary system, and improve the efficiency of therapeutic ERCP, new cannulation, sphincterotomy, and guide wire devices have been developed, based on principles of safe and successful therapeutic ERCP learned over the years. By totally re-engineering familiar accessories into smaller, more flexible, and more versatile devices, the 0.025-inch guide wire-based DASH system attempts to minimize the trauma at deep CBD cannulation and thereby increase the safety and success of achieving deep cannulation and sphincterotomy. Limited clinical experience to date suggests that the DASH system can provide full-function ERCP while reducing risks and costs. Attention to cannulation has led to the development of the RX Biliary System which provides the endoscopist and the assistant with increased control of the guide wire and exchange compared with traditional devices, resulting in less stress, less hand and wrist force used for contrast injection, and easier guide wire management, all of which have been shown in clinical trials to improve the speed and efficiency of ERCP while reducing complications.
Gastrointestinal Endoscopy | 1996
T.C.K. Tham; J. Vandervoort; R.C.K. Wong; David L. Carr-Locke; S. Chow; John J. Bosco; T. Qaseem; D.A. Howell; Douglas K. Pleskow; B. Vannemann
BACKGROUNDnWallstents (Schneider Stent, Inc., USA) used for the palliation of malignant biliary strictures, although associated with prolonged patency, can occlude. There is no consensus regarding the optimal management of Wallstent occlusion.nnnAIMSnTo evaluate the efficacy of different endoscopic methods for managing biliary Wallstent occlusion.nnnMETHODSnA multicentre retrospective study of patients managed for a biliary Wallstent occlusion.nnnRESULTSnData were available for 38 patients with 44 Wallstent occlusions, all of which had initial endoscopic management. Twenty four patients had died and 14 were alive after a median follow up of 231 (30-1095) days following Wallstent occlusion. Occlusions were managed by insertion of another Wallstent in 19, insertion of a plastic stent in 20, and mechanical cleaning in five. Endoscopic management was successful in 43 (98%). Following management of the occlusion, bilirubin decreased from 6.0 (0.5-34.3) to 2.1 (0.2-27.7) mg/100 ml (p < 0.05). No complications occurred. The median duration of second stent patency was 75 days (95% confidence interval 43 to 107) after insertion of another Wallstent, 90 days (71 to 109) after insertion of a plastic stent, and 34 days (30 to 38) after mechanical cleaning (NS). The respective median survivals were 70 days (22-118), 98 days (54-142), and 34 days (30-380) (NS). Incremental cost effective analysis showed that plastic stent insertion is the most cost effective option.nnnCONCLUSIONnAlthough all three methods are equally effective in managing an occluded Wallstent, the most cost effective method appears to be plastic stent insertion.
Gastrointestinal Endoscopy | 1996
D.A. Howell; T. Qaseem; Willis G. Parsons
Gastrointestinal Endoscopy | 1996
D.A. Howell; T. Qaseem; Brian L. Hanson; Willis G. Parsons; E. Elton; John J. Bosco
Gastrointestinal Endoscopy | 1997
D.A. Howell; E. Elton; T. Qaseem; Willis G. Parsons
Gastrointestinal Endoscopy | 1996
T. Qaseem; D.A. Howell; Willis G. Parsons; John J. Bosco
Gastrointestinal Endoscopy | 1996
D.A. Howell; T. Qaseem; John J. Bosco; E. Elton; Willis G. Parsons
Gastrointestinal Endoscopy | 1995
D.A. Howell; Brian L. Hanson; Willis G. Parsons; John J. Bosco; T. Qaseem
Successful Training in Gastrointestinal Endoscopy | 2011
D.A. Howell