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G Lehman

Publications and source records attributed to G Lehman.

At least 19 recordsLinked to original sources
PubMed2001

Endoscopic ultrasonography-guided fine-needle aspiration biopsy of suspected pancreatic cancer.

BACKGROUND: In many institutions, computed tomography (CT)-guided percutaneous fine-needle aspiration (FNA) has become the procedure of choice for biopsies of pancreatic mass lesions. This method of biopsy and others, such as endoscopic retrograde cholangiopancreatography (ERCP) cytology, are problematic because of a substantial false-negative rate. OBJECTIVE: To investigate the yield of endoscopic ultrasonography-guided FNA biopsies in patients who had negative results on CT-guided biopsy or negative cytologic findings on ERCP sampling. DESIGN: Prospective cohort study. SETTING: Tertiary care university medical center. PATIENTS: 102 patients (median age, 65 years; 58 men and 44 women) with suspected pancreatic cancer who fulfilled the above criteria were prospectively identified and underwent endoscopic ultrasonography-guided FNA biopsy. MEASUREMENTS: The operating characteristics of endoscopic ultrasonography-guided FNA for diagnosing pancreatic masses were determined. Surgical pathology or long-term follow-up (median, 24 months) was used to identify false-positive or false-negative results. RESULTS: Median mass size was 3.5 cm x 2.7 cm. A median of 3.4 passes were performed. Cytologic results on endoscopic ultrasonography-guided FNA biopsy were positive in 57 patients, negative in 37, and inconclusive or nondiagnostic in 8. No false-positive results were observed. A diagnosis of pancreatic cancer was subsequently confirmed in 3 patients who had tested negative (false-negative results) and 1 of the 8 patients with nondiagnostic results. Of these 4 patients, 3 had cytologic evidence of chronic pancreatitis on endoscopic ultrasonography-guided FNA biopsy. The 95% CI for the likelihood ratio for a positive test result contained all values greater than or equal to 9.7. The likelihood ratio for a negative test result was 0.05 (CI, 0.02 to 0.15). The posterior probability of pancreatic cancer after a definitely positive result was at least 93.5% by a conservative lower 95% confidence limit; after a definitely negative test result, it was 6.9%. The prevalence of pancreatic cancer was 59.8% (61 of 102 patients). Self-limited complications occurred in 3 of the 102 patients (2.9% [CI, 0.6% to 8.4%]). CONCLUSION: Endoscopic ultrasonography-guided FNA biopsy may play a valuable role in the evaluation of a pancreatic mass when results on other biopsy methods are negative but pancreatic cancer is suspected.

Aged↗
PubMed2001

Endoscopic ultrasound-guided celiac plexus block for managing abdominal pain associated with chronic pancreatitis: a prospective single center experience.

OBJECTIVE: In our previous randomized trial, we suggested a possible role for endoscopic ultrasound (EUS) guided celiac plexus block in the treatment of abdominal pain associated with chronic pancreatitis. The purpose of this study was to evaluate our prospective experience with EUS-guided celiac plexus block for controlling pain attributed to chronic pancreatitis, including follow-up on response rates and complications. METHODS: All subjects enrolled had documented chronic pancreatitis by ERCP and EUS criteria and presented with chronic abdominal pain unresponsive to current treatment options. All were treated with EUS-guided celiac plexus block under the guidance of linear array endosonography using a 22-gauge FNA needle (GIP, Mediglobe Inc., Tempe, AZ) inserted on each side of the celiac area, followed by injection of 10 cc bupivacaine (0.25%) and 3 cc (40 mg) triamcinolone on each side of the celiac plexus. Individual pain scores, based on a visual analog scale (0-10), were determined preblock and postblock by a nurse at 2, 7, 14 days and monthly thereafter. Subjects also rated their overall comfort level during the EUS procedure. RESULTS: EUS-guided celiac plexus block was performed in 90 subjects (40 males, 50 females) having a mean age of 45 yr (range 17-76 yr) between July 1, 1995 and December 30, 1996. A significant improvement in overall pain scores occurred in 55% (50/90) of patients. The mean pain score decreased from 8 to 2 post EUS celiac block at both 4 and 8 wk follow-up (p < 0.05). In 26% of patients there was persistent benefit beyond 12 wk, and 10% still had persistent benefit at 24 wk, including three patients who were pain-free between 35 and 48 wk. Younger patients (<45 yr of age) and those having previous pancreatic surgery for chronic pancreatitis were unlikely to respond to the EUS-guided celiac block. Three patients experienced diarrhea post EUS celiac block, which resolved in 7-10 days; however, it is unclear whether this diarrhea was due to the block or to refractory disease. A cost comparison between the EUS ($1200) and CT ($1400) techniques shows the EUS celiac block to be less costly and perhaps more cost efficient in a subset of subjects. CONCLUSIONS: EUS-guided celiac plexus block appears to be safe, effective, and economical for controlling pain in some patients with chronic pancreatitis. Younger patients (<45 yr) and those having prior pancreatic surgery for chronic pancreatitis do not appear to benefit from this technique. Prophylactic antibiotics should be considered if acid suppressing agents are being taken.

Abdominal Pain↗
PubMed2000

Endoscopic valvuloplasty for GERD.

BACKGROUND: The transoral, endoscopic route has been suggested as a possible approach for the correction of severe gastroesophageal reflux. Such a procedure would involve no mobilization of the cardia or other structures. The optimal placement, number, and configuration of sutures remains undefined. METHODS: With the use of a previously developed endoscopic sewing machine, this study was undertaken in baboons with two suture arrangements immediately below the lower esophageal sphincter. A linear arrangement (group I) and a circular arrangement (group II) were compared. During the 6 months after the procedure, the animals were evaluated using manometry, fluoroscopic barium swallow, upper gastrointestinal endoscopy, and a pressure volume test. RESULTS: A significant increase in lower esophageal sphincter length was demonstrated only in group II (p = 0. 010). A significant increase in lower esophageal sphincter pressure was demonstrated only in group I animals (p = 0.008). The abdominal length increased in group I (p = 0.004) and group II (p = 0.004). The yield pressure and yield volume did not differ significantly from those measured previously in control animals. No evidence of reflux, stricture formation, esophagitis, or other pathology was noted. CONCLUSIONS: Some manometric parameters associated with gastroesophageal reflux are altered by the endoscopic placement of sutures below the gastroesophageal junction, with no associated serious complications.

Animals↗
PubMed2000

In response

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Journal Article↗
PubMed2000

Endoscopic ultrasound characteristics of mucinous cystic neoplasms of the pancreas.

OBJECTIVE: Mucinous cystic neoplasms of the pancreas have a more favorable prognosis than ductal adenocarcinoma. Management of a subgroup, intraductal papillary-mucinous neoplasms, is controversial. Endoscopic ultrasound (EUS) with fine-needle aspiration biopsy may emerge as the imaging modality of choice. There are few studies describing the EUS features of these tumors. METHODS: A total of 35 consecutive cases of cystic tumors of the pancreas with an established pathological diagnosis were analyzed for characteristic EUS features. RESULTS: Mucinous cystadenocarcinomas (n = 14) were more likely to be characterized by hypoechoic cystic/solid mass or complex cyst and were frequently associated with a dilated main pancreatic duct. Benign mucinous duct ectasia (n = 6) were characterized by a dilated main pancreatic duct in conjunction with hyperechoic thickening of the duct wall. The two cases of intraductal mucinous hyperplasia additionally showed a hypoechoic mass. Intraductal papillary carcinoma (n = 11) had features in common with mucinous cystadenocarcinoma but also had echogenic foci in the mass and intraductal hyperechoic lesions. The two cases of microcystic cystadenoma showed either a mixed hypoechoic solid/cystic mass or a complex cyst without the additional features seen in mucinous cystadenocarcinoma. CONCLUSIONS: EUS features seem to exist that may help to differentiate cystic neoplasms from adenocarcinoma of the pancreas and, thus, to establish the preoperative diagnosis of cystic tumors of the pancreas.

Adult↗
PubMed1999

A prospective randomized comparison of endoscopic ultrasound- and computed tomography-guided celiac plexus block for managing chronic pancreatitis pain.

OBJECTIVE: Computed tomography (CT)-guided celiac plexus neurolysis has been used for controlling the chronic abdominal pain associated with intra-abdominal malignancy and chronic pancreatitis. Endoscopic ultrasound (EUS)-guided celiac plexus neurolysis has been reported to have some success in controlling pain from pancreatic cancer. The aim of this study is to assess the efficacy of EUS-guided celiac plexus block versus CT-guided celiac plexus block for controlling the chronic abdominal pain associated with chronic pancreatitis. METHODS: Patients enrolled were randomly assigned to EUS-guided or CT-guided celiac plexus block. Pain scores were determined pre- and postceliac block for both techniques. Follow-up was obtained by a nurse at 1 day post-block, then weekly thereafter for 24 wk. Patients also rated overall experience with these procedures. The EUS celiac block was performed with a 22-gauge sterile needle inserted into the celiac region with guidance of real-time linear array endosonography followed by injection of 10 ml of bupivacaine (0.75%) and 3 ml (40 mg) of triamcinolone on both sides of the celiac area. RESULTS: Twenty-two consecutive patients (10 men, 12 women), were ultimately enrolled in this study between 7/1/95 and 12/30/95; four patients were excluded for protocol violations. We performed EUS-guided celiac block in 10 patients and CT-guided celiac block in eight. A significant improvement in pain scores with reduction in pain medication usage occurred in 50% (five of 10) of patients having the EUS block. The mean postprocedure follow-up was 15 weeks (range: 8-24 wk). Persistent benefit was experienced by 40% of patients at 8 wk and by 30% at 24 wk. In the patients with CT block, however, only 25% (two of eight) had relief. The mean follow-up was 4 wk (range: 2-6 wk). Only 12% (one of eight) had some relief at 12 wk of follow-up. There were no complications. EUS-guided celiac block was the preferred technique among patients who experienced both techniques. A cost comparison between both celiac block techniques shows EUS to be less costly than CT. CONCLUSIONS: EUS-guided celiac block provided more persistent pain relief than CT-guided block and was the preferred technique among the subjects studied. EUS-guided celiac block appears to be a safe, effective, and less costly method for controlling the abdominal pain that can accompany chronic pancreatitis in some patients.

Abdominal Pain↗
PubMed1998

Effect of leuprolide acetate in treatment of abdominal pain and nausea in premenopausal women with functional bowel disease: a double-blind, placebo-controlled, randomized study.

We have previously reported impressive results in using a gonadotropin-releasing hormone analog, leuprolide acetate (Lupron), in the treatment of moderate to severe symptoms (especially abdominal pain and nausea) in patients with functional bowel disease (FBD). Pain is the hallmark of patients with FBD, and there is no consistent therapy for the treatment of these patients. The purpose of the present study was to expand the investigation to study similar patients (menstruating females) in a multicenter, double-blind, placebo-controlled, randomized study using Lupron Depot (which delivers a continuous dose of drug for one month), 3.75 mg (N = 32) or 7.5 mg (N = 33), or placebo (N = 35) given intramuscularly every four weeks for 16 weeks. Symptoms were assessed using daily diary cards to record abdominal pain, nausea, vomiting, early satiety, anorexia, bloating, and altered bowel habits. Additional assessment tools were quality of life questionnaires, psychological profile, oral-to-cecal transit using the hydrogen breath test, antroduodenal manometry, reproductive hormone levels, and global evaluations by both patient and investigator. Patients in both Lupron Depot-treated groups showed consistent improvement in symptoms; however, only the Lupron Depot 7.5 mg group showed a significant improvement for abdominal pain and nausea compared to placebo (P < 0.001). Patient quality of life assessments and global evaluations completed by both patient and investigators were highly significant compared to placebo (P < 0.001). All reproductive hormone levels significantly decreased for both Lupron Depot-treated groups by week 4 and were significantly different compared to placebo at week 16 (P < 0.001). This study shows that leuprolide acetate is effective in controlling the debilitating symptoms of abdominal pain and nausea in patients with FBD.

Abdominal Pain↗
PubMed1997

Use of the 25 mm flanged esophageal Z stent for malignant dysphagia: a prospective multicenter trial.

BACKGROUND: An initial multicenter study using a 21 mm flanged esophageal Z stent demonstrated excellent palliation but an 11% immediate complication rate at placement and a 27% migration rate at 1 month. This North American multicenter trial prospectively studied a 25 mm flanged Z stent to define its palliative ability and whether the increased diameter affected placement or migration problems. METHODS: Fifty patients who had esophageal Z stents at seven university or regional referral hospitals were prospectively studied. Indications for prosthesis placement, previous therapy, patient demographics, incidence of concomitant tracheoesophageal fistula, and degree of dysphagia were defined, as were procedural and subsequent stent-related problems, survival times, the ability to occlude a tracheoesophageal fistula, and subsequent degree of dysphagia. RESULTS: Twenty-four patients had infiltrating malignancy (16 exophytic and 10 extrinsic), 9 of whom had concomitant tracheoesophageal fistulas. Ten patients (20%) had misplaced stents requiring retrieval and replacement, 12 patients (24%) had subsequent stent-related problems including exsanguination (2), aspiration (3), tumor overgrowth (3), and postplacement migration (4) (8%). There was statistically significant improvement in prestent versus poststent dysphagia and two thirds of patients had complete occlusion of their tracheoesophageal fistula. CONCLUSIONS: Redesign of the esophageal Z stent has decreased the migration rate without increasing placement or subsequent erosion problems. Its efficacy appears comparable to the currently marketed Z stent for the palliation of malignant dysphagia and occlusion of tracheoesophageal fistula.

Aged↗
PubMed1997

Radial scanning and linear array endosonography for staging pancreatic cancer: a prospective randomized comparison.

BACKGROUND: Endoscopic ultrasound (EUS) is known to be accurate for staging pancreatic cancer. Little data exist to determine if linear array or radial scanning EUS is superior for staging pancreatic cancer. This prospective comparison was undertaken to assess the accuracy of linear array and radial scanning EUS for staging pancreatic cancer. METHODS: Patients with pancreatic cancer referred for EUS staging were randomized to linear array or radial scanning EUS. Staging accuracy for each was determined by comparison to surgical pathology in those patients going to surgery. RESULTS: Seventy-nine patients with pancreatic cancer were enrolled and 33 had surgical resection. Of these, 17 patients were randomized to linear array and 16 to radial scanning EUS. The remaining 46 patients did not have surgery because of comorbid illness or clinically unresectable disease. EUS staging accuracy for linear array was 94% (16 of 17) for T and 71% (12 of 17) for N staging, whereas radial scanning was 88% (14 of 16) for T and 75% (12 of 16) for N staging. For predicting vascular invasion, radial scanning was 100% accurate (16 of 16) while linear array was 94% (16 of 17) accurate. There was one false-negative assessment of invasion using linear array EUS. CONCLUSION: Overall, both EUS designs appear equivalent for staging pancreatic cancer and assessing vascular invasion. In view of our findings and the capability for ultrasound-directed fine-needle aspiration with linear array EUS, this instrument may be the preferred choice for evaluating pancreatic masses.

Adenocarcinoma↗
PubMed1996

Presentation of choledochal cysts without intrabiliary communication on endoscopic retrograde cholangiopancreatography.

Choledochal cysts have generally been described to communicate with the biliary system. We recently saw three adult patients in whom we could not demonstrate biliary communication between the cyst and the biliary tree, despite a carefully performed endoscopic cholangiopancreatography (ERCP). These cases may represent a variant of type II choledochal cysts. During the 5-year period of review of ERCP records, 30 choledochal cysts were diagnosed, of which 3 (10%) were the noncommunicating cases described in this report.

Adult↗
PubMed1995

Experience with a catheter-based ultrasound probe in the bile duct and pancreas.

BACKGROUND AND STUDY AIMS: Complete examination of the biliary tree and pancreatic duct may be difficult or unsuccessful using conventional imaging instruments. The purpose of this study was to evaluate the cannulation success rate, clinical utility, and safety of a new catheter-based ultrasound probe (CBUSP) used in the biliary tree and pancreas. PATIENTS AND METHODS: The probes used in this study are manufactured by Microvasive (Watertown, MA, U.S.A.) and were 6.2 Fr in diameter, operated at 12.5 MHz. Thirty-six patients (11 with malignant bile-duct strictures, 12 with benign bile-duct strictures, two with bile duct stones, three with pancreatic duct strictures, one with a pancreatic cyst, one with pancreas divisum, three with sphincter of Oddi dysfunction, and three normal) underwent examination with a CBUSP. RESULTS: Cannulation was successful in all 36 patients. The hepatic artery and portal vein could be visualized with the probe in the proximal bile duct in 81% and 94% of the cases, respectively. The portal vein could not be adequately visualized in any patients when the probe was in the distal bile duct. The mean thickness of the normal bile duct wall was 0.17 cm, and the mean wall thicknesses proximal to a benign and malignant stricture were 0.16 and 0.17 cm, respectively. The mean thicknesses of benign and malignant biliary strictures were 0.32 cm and 0.31 cm, respectively (not significant). Eight of 12 benign biliary strictures (67%) and five of 11 malignant strictures (45%) were symmetrical. However, no obvious differences could be identified between benign and malignant biliary strictures. There were no catheter related complications. CONCLUSIONS: Further catheter modifications are needed, but it appears to be feasible to assess vascular invasion in cholangiocarcinoma and to characterize biliary strictures in a way that may be able to influence therapy options in some patients. The currently available CBUSP cannot distinguish between benign and malignant strictures. However, with technical modifications, this may be possible in the future. The clinical usefulness of CBUSP in the pancreas awaits further investigation, but pancreatic imaging is feasible.

Adult↗
PubMed1994

Survey of informed consent for endoscopic retrograde cholangiopancreatography.

Prior to performance of gastrointestinal endoscopic procedures, physicians are generally required to appraise patients of potential risks, benefits, and alternatives. Components of the informed consent process require that: (1) consent be voluntary; (2) the patient be sufficiently mentally capable to engage in rational decision-making; and (3) "adequate information" be conveyed. Controversies reflected in both medical and legal literature concern the definition of "adequate information." To sample current opinion regarding consent for both diagnostic and therapeutic ERCP, members of the Indiana Gut Club and Midwest Gut Club were polled. From this group of academic and private practice physicians, 81 completed evaluations were compiled. Greater than 90% of physicians believed that pancreatitis and pancreatitis/bleeding/perforation must be mentioned for diagnostic and therapeutic ERCP, respectively. There was variation of opinion as to whether patients must be informed of potential need for surgery, prolonged hospital stay, or death. The performing physician was felt to be ultimately responsible for obtaining consent, although other health-care team members, excluding a secretary, could participate.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1991

Extracerebral course of the perforating branches of the anterior communicating artery: microsurgical anatomical study.

Damage to the perforating branches arising from the anterior communicating artery, because of their blood supply to the septal nuclei and anterior hypothalamus, explains the memory impairment and the electrolyte disturbances that often follow the surgery of aneurysms located in this part of the circle of Willis. The microsurgical anatomy of these branches was studied on 60 fixed human brains, with special attention to their number, caliber, and vascular territory. The direction of the branches was evaluated, measuring the angle formed by them with the postcommunicating segment of the anterior cerebral artery. The variability of this anatomical region is discussed in light of the literature.

Cerebral Arteries↗
PubMed1989

Studies on the influx of [3H]-histidine and 45Ca through a surgical opening to rat incisor ameloblasts and adjacent enamel.

Considerable controversy exists about the role of ameloblasts in transport of calcium to mineralizing enamel. The rate and pattern of incorporation of calcium and an enamel precursor (histidine) were studied autoradiographically by introducing the isotopes through a surgically created defect in the lower border of the rat mandible. Influx of the isotopes to both secretory and maturation ameloblasts and adjacent enamel was examined in large survey sections of the entire incisor at intervals of 3 min to 2 h. Substantial concentrations of silver grains were observed over both secretory and maturation ameloblasts within 5 min of placement of either isotope. 45Ca was also present in secretory and maturation enamel within this short time. The overall patterns of influx and uptake of both precursors were similar to those found when such isotopes have been administered parenterally. The amount of influx of 45Ca across secretory, smooth-ended, and ruffle-ended maturation ameloblasts was compared qualitatively and found to be similar. The reproducibility of this surgical technique was demonstrated as well as its usefulness in combination with survey sections for multi-method investigations of rat incisor enamel formation and mineralization.

Ameloblasts↗