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D A Howell

Publications and source records attributed to D A Howell.

At least 19 recordsLinked to original sources
PubMed2006

Endoscopic resection of benign tumors of the papilla of vater.

Most benign papillary tumors are adenomas which can potentially undergo the adenoma-carcinoma-sequence making complete removal mandatory for curative therapy. Endoscopic resection (papillectomy) of these lesions is being increasingly performed as a less traumatic alternative to surgery. Available data shows endoscopic papillectomy to be effective and safe in experienced hands with usually little morbidity and virtually no mortality. Success rates are around 80 % for lesions without intraductal involvement. Selected cases of limited distal intraductal involvement accessible after sphincterotomy may also be managed curatively by endoscopic resection. Endoscopic snare resection of entire lesions should be primarily regarded as a diagnostic procedure. It allows for an accurate histological diagnosis based on examination of the entire specimen rather than forceps biopsies and thus a reliable assessment of the need for surgical therapy. Subsequent surgery in operable patients is not precluded by previous endoscopic resection. Surgery is indicated in case of incomplete removal and if malignancy is present. The curative role of endoscopic papillectomy for early invasive carcinoma needs to be established. Histological features and individual risk for surgery are factors to be considered. Inoperable patients may still benefit from palliative endoscopic stenting. After endoscopic papillectomy has been completed, regular follow-up examinations including biopsies are warranted because of the risk of local recurrence. For benign looking papillary tumors, endoscopic papillectomy serves as a diagnostic tool and should be considered as first line procedure regardless of age. The following article details the approach to patients with benign papillary tumor and the technique of endoscopic papillectomy.

Ampulla of Vater↗
PubMed2006

Lymphoma: variations in time to diagnosis and treatment.

This study examines illness trajectories of patients with lymphoma and assesses whether UK government targets to reduce waiting time for diagnosis and treatment are achievable and appropriate. One hundred and ninety-four patients, residents in West Yorkshire, aged more than 25 years and newly diagnosed with lymphoma during 2000 were included. Data collected from interviews, primary care and hospital records were used to examine time between critical events on the illness trajectory and characteristics of patients not meeting proposed targets. Forty-two per cent of patients did not receive a hospital appointment within 2 weeks of general practitioner referral, 26% were not treated within 1 month of diagnosis and 64% were not treated within 2 months of referral. Target achievement differed by diagnostic group, and trends were seen by age and deprivation. The interval from onset of symptoms to treatment averaged more than 1 year and approximately half of this occurred before first medical contact. Results suggest that significant improvements are needed to achieve targets. Although existing targets particularly address referral and treatment intervals, these were the shortest intervals on the trajectory. Generalized targets may be inappropriate and unachievable for lymphoma as they do not consider individual disease characteristics or allow for variations in the urgency with which treatment is needed.

Adult↗
PubMed2001

Endoscopic management of tumors of the major duodenal papilla: Refined techniques to improve outcome and avoid complications.

BACKGROUND: Adenomas of the major duodenal papilla have malignant potential and are traditionally treated by pancreaticoduodenectomy. This is a report of our experience with endoscopic management and a description of techniques for decreasing complications and enhancing efficacy. METHODS: Forty-one patients were referred for endoscopic management of papillary tumors. If there was no duct invasion and the appearance suggested a benign lesion, biductal sphincterotomy with pancreatic duct stent placement was performed. If the lesion could be elevated by injection of an epinephrine solution, piecemeal resection was performed. The base of the lesion was thermally ablated as needed. Resection/ablation together with stent removal was performed 1 month later. RESULTS: Nine patients (22%) had lesions other than papillary adenoma or cancer. Malignant appearance, ductal stricturing, or extension into the ducts was found in 16 of 41 patients (39%) in whom biopsy specimens alone were obtained. Three patients with adenomas (7%) did not undergo endoscopic resection (because of extremely large lesions and/or comorbid illnesses). Thirteen patients with adenomas (32%) had endoscopic resection; 12 (92%) were lesion-free after 32 ERCPs (mean 2.7). Endoscopic management was unsuccessful in 1 patient (8%). Pancreatitis developed in 1 patient. CONCLUSIONS: Endoscopically treatable papillary neoplasms can be identified on the basis of endoscopic, radiographic, and biopsy features. Preresection sphincterotomy, stent placement, elevation by epinephrine injection, and piecemeal resection may reduce complications and permit more aggressive treatment.

Adenoma↗
PubMed2000

Infected pancreatic pseudocysts with colonic fistula formation successfully managed by endoscopic drainage alone: report of two cases.

Fistulization of pancreatic pseudocysts into surrounding viscera is a well-known phenomenon and usually requires surgical management. We report two cases of pancreatic pseudocysts that developed spontaneous fistulas to the colon with resulting fever and abdominal pain. The patients were managed nonoperatively with a combination of endoscopic drainage and antibiotics, and their pseudocysts and fistulas resolved. The patients have remained symptom-free for a mean of 14 months of follow-up.

Abdominal Abscess↗
PubMed1999

Endoscopic treatment of pancreatic duct stones using a 10F pancreatoscope and electrohydraulic lithotripsy.

BACKGROUND: Endoscopic therapy with adjunctive extracorporeal shock wave lithotripsy fails to provide clearance of pancreatic duct stones in up to 25% of symptomatic patients. Direct contact lithotripsy may provide an additional option for removal of refractory stones. We report our initial experience using a prototype 10F "baby" endoscope to administer electrohydraulic lithotripsy. METHODS: Five patients failing extracorporeal shock wave lithotripsy and one patient with recurrent pancreatic duct stones after surgery were selected to undergo endoscopic electrohydraulic lithotripsy. After pancreatic sphincterotomy and balloon dilation (8 or 10 mm), the 10F endoscope was introduced and electrohydraulic lithotripsy was used to fragment stones under direct visualization. RESULTS: Six patients underwent 9 intraductal electrohydraulic lithotripsy procedures. Complete or partial pancreatic duct clearance was accomplished in all but one. No complications from the lithotripsy procedure were noted. The 5 patients with partial or complete duct clearance experienced complete relief of abdominal pain of at least 6 months' duration following their final procedure. CONCLUSION: Electrohydraulic lithotripsy within the pancreatic duct provides an adjunctive endoscopic option for treatment of patients with symptomatic pancreatic duct stones. Our initial experience suggests that electrohydraulic lithotripsy therapy can successfully fragment stones refractory to conventional endoscopic stone extraction methods or extracorporeal shock wave lithotripsy. Further experience is necessary to establish the risks of electrohydraulic lithotripsy within the pancreatic duct.

Aged↗
PubMed1999

Endoscopically placed Gianturco endoprosthesis in the treatment of malignant and benign biliary obstruction.

Since the introduction of the Z-stent by Cesare Gianturco in 1985, the prominent role of endoscopically placed transpapillary endoprostheses as the treatment of choice to relieve malignant biliary obstruction has stimulated much interest and research in the evolution of his initial design. This article reviews the efficacy and limitation of prior Z-stent models in their attempt to relieve malignant and benign biliary obstructions and previews improvements in the design currently being evaluated in a large, multicenter trial.

Animals↗
PubMed1998

Dilated common channel syndrome: endoscopic diagnosis, treatment, and relationship to choledochocele formation.

BACKGROUND: Choledochoceles (type III biliary cysts) are cystic dilations of the terminal common bile duct or common pancreatobiliary channel. Although no size criteria have been defined, it is generally assumed these must be large. However, we describe patients who do not meet the perceived size criteria for choledochoceles, but who nonetheless have a dilated common pancreatobiliary channel. METHODS: We reviewed the presenting symptoms, endoscopic and radiographic findings, and response to endoscopic therapy of patients meeting our criteria for the dilated common channel syndrome. RESULTS: Of 2847 patients undergoing ERCP, 100 (3.5%) had the dilated common channel syndrome. Common presenting symptoms and signs included abdominal pain in 97%, abnormal liver function test(s) in 66%, and a history of acute or recurrent pancreatitis in 46%. A bulge was visible above the papilla in 88%, with a dilated common bile duct in 54% and a dilated pancreatic duct in 28%. After endoscopic unroofing of the common channel, 77% had complete and long-lasting resolution of symptoms, 18% had partial or transient improvement, and 5% had no change. CONCLUSIONS: Although classic choledochoceles are rare, a lesser degree of dilation of the common channel is more frequent than generally appreciated. We postulate that this finding represents an "incomplete," acquired form of choledochocele, possibly caused by underlying papillary stenosis. Whatever the etiology and appropriate term, the presence of a dilated common channel predicts a high rate of clinical response to endoscopic therapy.

Adult↗
PubMed1998

Endoscopic pancreatic sphincterotomy: indications, outcome, and a safe stentless technique.

BACKGROUND: Endoscopic pancreatic sphincterotomy is less widely practiced than biliary sphincterotomy, in part because of the lack of firm data regarding its indications and safety. In addition, recent reports of ductal and parenchymal changes occurring after pancreatic stenting raise concerns about the standard practice of stent placement at the time of pancreatic sphincterotomy. We report our experience with pancreatic sphincterotomy and describe the use of a technique involving overnight nasopancreatic drainage rather than stenting. METHODS: We reviewed the records of the 164 pancreatic sphincterotomies performed on 160 patients at our institution between January 1, 1991, and October 1, 1996, comparing procedures done with overnight nasopancreatic catheter placement with those done with stenting or no drainage. We also examined the long-term clinical outcome of patients after pancreatic sphincterotomy. RESULTS: Of the 164 sphincterotomies, 98 were done with overnight nasopancreatic drainage, 50 with stent placement, and 16 with no drainage. Complications (all pancreatitis) were significantly more frequent in the group with no drainage (12.5%) as compared with those with drainage (0.7%); p < 0.003. Nasopancreatic drainage was as safe as stent placement, with no complications after 98 procedures. Pancreatic sphincterotomy was effective when used as primary therapy, with 64% of patients so treated experiencing complete and long-lasting resolution of symptoms after the procedure. CONCLUSIONS: Pancreatic sphincterotomy is safe and effective, although pancreatic drainage is required to reduce the incidence of pancreatitis. Overnight nasopancreatic drainage is the method of choice, as it carries as low a complication rate as stent placement, but without the need for a repeat procedure, and presumably without the risk of ductal and parenchymal damage.

Case-Control Studies↗
PubMed1998

Endoscopic sphincterotomy for stones by experts is safe, even in younger patients with normal ducts.

OBJECTIVE: To provide current information on the risks of endoscopic sphincterotomy for stone. SUMMARY BACKGROUND DATA: In recent years (since the popularity of laparoscopic cholecystectomy), endoscopic sphincterotomy has been used increasingly for the management of bile duct stones in relatively young and healthy patients. The validity of this trend has been questioned using data on short-term complications derived from earlier decades that involved more elderly and high-risk patients. METHODS: Seven academic centers collected data prospectively using a common database. Complications within 30 days of the procedures were documented by standard criteria. RESULTS: Of 1921 patients, 112 (5.8%) developed complications; two thirds of these events were graded as mild (<3 days in hospital). There was no evidence of increased risk in younger patients or in those with smaller bile ducts. There was only one severe complication and there were no fatalities in 238 patients age <60, with bile duct diameters of <9 mm. CONCLUSION: Sphincterotomy for stones can be performed very safely by experienced endoscopists.

Age Factors↗
PubMed1998

Endoscopic management of pseudocysts of the pancreas.

Endoscopic pseudocyst management should not be regarded as an exercise in applied technology. Rather, it is of vital importance for the clinician to be thoroughly aware of the many considerations in patient selection and to understand the available treatment alternatives prior to undertaking such a venture. Despite these considerations, it is our opinion that endoscopic pseudocyst management at present is the method of choice in the majority of patients requiring drainage of symptomatic pseudocysts.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1996

Multidisciplinary approach to pseudoaneurysms complicating pancreatic pseudocysts. Impact of pretreatment diagnosis.

OBJECTIVE: To determine the effectiveness of thin-section, dynamic-contrast computed tomography and angiography in detecting the presence of pancreatic pseudoaneurysms. DESIGN: This case series consisted of 57 patients who were being examined for endoscopic drainage of pancreatic pseudocysts. SETTING: All patients were examined in a tertiary care, teaching hospital. PATIENTS: Fifty-seven consecutive patients were examined for 2 years. Follow-up ranged from 6 months to 2 years. INTERVENTIONS: All patients underwent thin-section, high-speed, dynamic-contrast computed tomography. Those patients with findings that were consistent with the presence of a pseudoaneurysm underwent angiography. Embolization was attempted if a pseudoaneurysm was present. Endoscopic retrograde cholangiopancreatography was used to determine pancreatic ductal anatomy before operation. MAIN OUTCOME MEASURE: No undetected pseudoaneurysm has complicated this series of endoscopically drained pseudocysts. RESULTS: Five patients had findings that were consistent with a pancreatic pseudoaneurysm on computed tomography. Angiographic findings confirmed a pseudoaneurysm in four patients, and angiographic embolization was successful in three. Four patients underwent resection, while one was treated with embolization and endoscopic stenting of a compressed pancreatic duct. There were no mortalities. CONCLUSIONS: Before endoscopic drainage of a pancreatic pseudocyst, a thin-section, high-speed, dynamic-contrast computed tomographic scan is essential. If there are findings consistent with the development of a pseudoaneurysm, angiography must be performed. This allows delineation of the arterial anatomy, as well as the option of performing angiographic embolization. While patients with pseudoaneurysms in the body and tail of the pancreas underwent resection, angiographic embolization alone was an acceptable alternative when the lesion was located in the head of the pancreas.

Adult↗
PubMed1995

Combined modality treatment of symptomatic pancreatic ductal lithiasis.

OBJECTIVE: To assess the efficacy and safety of the removal of pancreatic duct stones by a combined modality approach in patients with pancreatic ductal lithiasis and recurrent abdominal pain. DESIGN: Retrospective review with a mean follow-up of 19 months (range, 1 to 56 months). SETTING: A tertiary care, private community hospital with a university affiliation. PATIENTS: The records of patients who presented to the hospital or who were referred with recurrent abdominal pain and who were demonstrated to have pancreatic ductal lithiasis between 1989 and 1994 were reviewed. Patients were assessed by their clinical response to pancreatic duct stone extraction by a variety of therapeutic interventions. RESULTS: Fifteen patients were included in the study. One patient was excluded from analysis because of a concurrent choledochocele. Two patients required operative decompression and stone extraction for endoscopically inaccessible stones. Six patients were treated with endoscopic management alone, and six were treated with a combination of extracorporeal shock wave lithotripsy and endoscopic stone retrieval. Twelve patients had complete clearance of the pancreatic duct. One patient had a stone that was not removed, but adequate pancreatic ductal decompression was achieved. The remaining patient had incomplete clearance of pancreatic stone fragments following extracorporeal shock wave lithotripsy but had adequate ductal drainage. No patient has required further therapy or hospitalization for abdominal pain. No complications occurred as a result of any intervention in this study. CONCLUSIONS: A multidisciplinary combined modality approach is a safe and effective method for extracting pancreatic duct stones in symptomatic patients. Stone extraction and reestablishment of adequate ductal drainage appear to relieve symptoms in some patients.

Abdominal Pain↗
PubMed1992

Symptomatic choledochoceles in adults. Endoscopic retrograde cholangiopancreatography recognition and management.

During a 2-year interval, we identified 10 patients with symptoms of pancreaticobiliary disorders and small choledochoceles by endoscopic retrograde cholangiopancreatography. Patients ranged from 36 to 89 years of age. Eight were female. Seven presented with recurrent, acute pancreatitis, two presented with biliary colic, and one presented with cholangitis. Dilated common bile ducts were seen in four patients, and no other biliary lesions were demonstrated in any patients. Five patients were shown to have normal gallbladders by ultrasonographic or computed tomographic criteria. Choledochoceles were identified endoscopically as a bulge above or involving the ampulla. Diagnosis was confirmed by cholangiography. All patients underwent successful unroofing of the choledochocele and sphincterotomy of the common bile duct. One pancreatic sphincterotomy was performed for pancreatic ductal obstruction. We encountered no complications. Hospital stays ranged from 1 to 4 days. Follow-up intervals ranged from 2 to 20 months. At this time, no patients have had any recurrence of symptoms, and none has required rehospitalization or surgery.

Adult↗
PubMed1992

Endoscopic management of cystic duct fistulas after laparoscopic cholecystectomy.

Two patients are reported who developed bile ascites as a result of cystic duct fistulas following laparoscopic cholecystectomy. Both patients were successfully treated with endoscopic retrograde cholangiopancreatography, utilizing sphincterotomy and nasobiliary tube placement. Characteristics of this syndrome and advantages of this form of therapy are emphasized.

Adult↗