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Biomedical subjects

S Sherman

Publications and source records attributed to S Sherman.

At least 109 records · Page 6Linked to original sources
PubMed1996

Sphincter of Oddi dysfunction.

Evidence continues to accumulate indicating that sphincter of Oddi dysfunction may give rise to cholestasis, pancreatitis, or upper abdominal pain syndromes. Diagnosis of such dysfunction may be inferred from noninvasive tests or more precisely defined by manometric studies. Both the biliary and pancreatic sphincters are commonly involved. If medical therapy is ineffective, sphincter ablation via endoscopy or laparotomy should be considered for highly symptomatic patients. Complication rates of invasive techniques remain relatively high and risk:benefit ratio should be carefully considered. Future research as to etiology, more defined pathophysiology, more accurate noninvasive evaluation, and optimal therapies are awaited.

Common Bile Duct Diseases↗
PubMed1996

Effects of meperidine on the pancreatic and biliary sphincter.

BACKGROUND: Opioids are traditionally avoided during sphincter of Oddi manometry because of indirect evidence suggesting that these agents cause sphincter of Oddi spasm. This study was undertaken to determine the direct effects of meperidine on the biliary and pancreatic sphincter. METHODS: Forty-seven patients were prospectively evaluated by sphincter of Oddi manometry in the conventional retrograde fashion. Manometry was initially performed with intravenous diazepam sedation alone. The manometry was repeated 3 to 5 minutes after meperidine was administered. RESULTS: The basal sphincter pressure of the biliary sphincter, pancreatic sphincter, and the combined sphincter group were not significantly altered by meperidine. Concordance (normal versus abnormal) between the basal sphincter pressure before and after meperidine was seen in 44 of 47 patients (94%). Meperidine produced a significant increase in the pancreatic, biliary, and combined sphincter phasic frequency and a significant decrease in the phasic duration. The pancreatic and combined sphincter phasic pressures were significantly reduced following meperidine administration. Seventeen manometry tracings (36%) were believed to be qualitatively better after meperidine, while only four (8.5%; p < .001) were qualitatively better with diazepam alone. CONCLUSION: Meperidine can be used for additional analgesia during sphincter of Oddi manometry if the basal sphincter pressure is the parameter used to determine therapy.

Humans↗
PubMed1996

Alterations in pancreatic ductal morphology following polyethylene pancreatic stent therapy.

BACKGROUND: Polyethylene stents placed in the main pancreatic duct induce morphologic alterations that may resemble chronic pancreatitis. METHODS: We reviewed the sequential pancreatograms of stented patients who had long-term follow-up after stent removal. RESULTS: Forty patients (66%) had a normal baseline pancreatogram, whereas 21 (34%) showed changes of chronic pancreatitis. In 49 of 61 patients (80.3%), one or more had new morphologic changes immediately after stent withdrawal graded as mild (69%), moderate (29%), or severe (2%). Changes included ductal irregularity (49%), narrowing (35.5%), and side branch change (15.5%). Sixteen of the 21 patients (76.1%) with an abnormal baseline pancreatogram had worsening of the baseline abnormality or additional changes while stented, whereas 33 of 40 (82.5%) with a normal baseline developed new morphologic changes. Correlation of stent-induced changes with stent size, length, patency at removal, and duration of stenting failed to show an association. Twenty-five patients with stent-induced changes had a follow-up pancreatogram at a mean of 192 days (10 to 740) after stent removal. There was complete resolution of the changes in 64%, partial resolution in 32%, and no improvement in 5%. CONCLUSION: Morphologic changes induced by polyethylene pancreatic duct stents occurred in 80% of patients. More than one third of these changes did not resolve during the follow-up period. Because of concern over stent-induced fibrosis, the use of pancreatic stents should remain largely experimental.

Follow-Up Studies↗
PubMed1996

Stent-induced pancreatic ductal and parenchymal changes: correlation of endoscopic ultrasound with ERCP.

BACKGROUND: Polyethylene pancreatic duct stents induce morphologic changes of the pancreatic duct in the majority of patients. This study was undertaken to determine if parenchymal abnormalities are present in patients undergoing short-term pancreatic duct stenting and to correlate these findings with the pancreatogram obtained at stent removal. METHODS: Twenty-five patients underwent pancreatic duct stenting and had an endoscopic ultrasound evaluation of the pancreas at stent removal. The pancreatograms were evaluated at stent removal for ductal irregularity, narrowing, and side branch changes. Endoscopic ultrasound was used to assess for differences in the echo characteristics of the pancreatic parenchyma around the stent compared with the rest of the gland. RESULTS: Of the 16 patients evaluated by ERCP at stent removal, 9 (56%) had 1 or more new ductographic changes. Endoscopic ultrasound identified parenchymal changes in the stented region in 17 of 25 patients (68%). Four patients who had parenchymal changes in the stented region on endoscopic ultrasound at stent removal had a follow-up study at a mean time of 16 months. Two patients had (new) changes suggestive of focal chronic pancreatitis in the stented region. CONCLUSION: Short-term pancreatic duct stenting induced both ductal and parenchymal changes in more than 50% of patients. Chronic pancreatitis may be a consequence of pancreatic duct stenting.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1996

Radiation exposure to patients and personnel during interventional ERCP at a teaching institution.

BACKGROUND: This study was designed to determine the radiation dose to patients and personnel during ERCP procedures. METHODS: Phantom studies were performed to compare dosimetry for two image capture systems and to determine the effectiveness of shielding in reducing stray radiation. Radiation techniques and dosimetry were recorded in 72 patients undergoing ERCP. RESULTS: Phantom studies indicated that increasing fluoroscopy voltage from 75 to 96 kV decreased entrance dose by 50%. Image capture by digital radiography decreased radiation exposure by 66%. Shielding decreased stray radiation exposure by 93%. All patients underwent cholangiography (n = 71) and/or pancreatography (n = 53). The mean number of interventional ERCP procedures performed per patient was 1.8 (range, 0 to 6). The mean measured patient entrance dose was 80 mGy (8 R; range, 0.2 to 73 R); however, the calculated mean entrance dose (based on measured intensifying screen doses) may have been as high as 3000 mGy (30 R; range, 0.8 to 300 R). Measured patient exposure increased with fluoroscopy time (r = 0.9) and with the number of interventions performed (r = 0.3). The mean dose to personnel was estimated at 0.04 mR. CONCLUSIONS: The patient radiation dose depended most on fluoroscopy time. The dose may be lowered by minimizing fluoroscopy time, using higher voltage and lower current for fluoroscopy, and using digital radiography for documentation. Personnel were adequately protected.

Adult↗
PubMed1996

Recombination and nondisjunction in humans and flies.

Recent studies of Drosophila and humans indicate that aberrant genetic recombination is an important component of nondisjunction in both species. In both, a proportion of nondisjunction is associated with failure to pair and/or recombine and in both, exchanges which are either too distal or too proximal increase the likelihood of malsegregation. In this review we provide two perspectives on these observations: first, a review of exchange and chromosome segregation in model organisms, focusing on Drosophila, and secondly an overview of nondisjunction in humans. This format allows us to describe the paradigms developed from studies of model organisms and to ask whether these paradigms apply to the human situation.

Animals↗
PubMed1996

Restructuring VA ambulatory care and medical education: the PACE model of primary care.

The Veterans Health Administration (VHA) Western Region and associated medical schools formulated a set of recommendations for an improved ambulatory health care delivery system during a 1988 strategic planning conference. As a result, the Department of Veterans Affairs (VA) Medical Center in Sepulveda, California, initiated the Pilot (now Primary) Ambulatory Care and Education (PACE) program in 1990 to implement and evaluate a model program. The PACE program represents a significant departure from traditional VA and non-VA academic medical center care, shifting the focus of care from the inpatient to the outpatient setting. From its inception, the PACE program has used an interdisciplinary team approach with three independent global care firms. Each firm is interdisciplinary in composition, with a matrix management structure that expands role function and empowers team members. Emphasis is on managed primary care, stressing a biopsychosocial approach and cost-effective comprehensive care emphasizing prevention and health maintenance. Information management is provided through a network of personal computers that serve as a front end to the VHA Decentralized Hospital Computer Program (DHCP) mainframe. In addition to providing comprehensive and cost-effective care, the PACE program educates trainees in all health care disciplines, conducts research, and disseminates information about important procedures and outcomes. Undergraduate and graduate trainees from 11 health care disciplines rotate through the PACE program to learn an integrated approach to managed ambulatory care delivery. All trainees are involved in a problem-based approach to learning that emphasizes shared training experiences among health care disciplines. This paper describes the transitional phases of the PACE program (strategic planning, reorganization, and quality improvement) that are relevant for other institutions that are shifting to training programs emphasizing primary and ambulatory care.

Ambulatory Care↗
PubMed1996

Complex biliary stones: treatment with a small choledochoscope and laser lithotripsy.

PURPOSE: To evaluate the use of a small choledochoscope and laser lithotripsy in the treatment of complex biliary stone disease. MATERIALS AND METHODS: Twenty-five consecutive patients with complex biliary stone disease not amenable to surgical therapy, peroral endoscopic removal, or simple percutaneous retrieval techniques underwent 35 stone-removal procedures. A 3.4-mm endoscope and a pulsed dye coumarin green laser were used to pulverize and remove stones through preexisting, mature transhepatic biliary drain tracts (n = 18), t-tube tracts (n = 3), cholecystostomy tube tracts (n = 3), and a hepaticocutaneous enterostomy (n = 1). Procedures in 14 of the 25 patients (56%) were performed on an outpatient basis. RESULTS: Twenty-four of the 25 patients (96%) were cleared of their stone burden and underwent subsequent catheter therapy of strictures or abscesses as necessary. Complications of the stone removal included fever and chills in six patients (24%) and mild bleeding from a bile duct wall during removal of an adherent stone in one patient. CONCLUSION: Use of a small choledochoscope and a coumarin green pulsed dye laser is safe and effective in the management of complex biliary stone disease.

Bile Duct Diseases↗
PubMed1996

Early recognition of post-ERCP pancreatitis by clinical assessment and serum pancreatic enzymes.

BACKGROUND: This study evaluates the relative value of clinical assessment and serum pancreatic enzymes in the discharge management of outpatients undergoing ERCP. METHODS: Two hundred thirty-one patients who underwent ERCP had a detailed clinical assessment performed 2 h after the procedure and blood drawn for amylase and lipase. RESULTS: One-third of the patients who later developed pancreatitis had no pain 2 h after the end of the procedure, whereas an equal number who had no pancreatitis did complain of pain. Values below 276 U/L for amylase and 1000 U/L for lipase were useful in ruling out pancreatitis with negative predictive values of 0.97 and 0.98, respectively. Based on the data of this study a discharge algorithm for outpatients undergoing ERCP is proposed. CONCLUSIONS: In contrast to clinical assessment, which is unreliable, it is possible to stratify patients according to their risk of developing pancreatitis according to their 2-h serum amylase and lipase values. This helps to rationalize the discharge management of outpatients undergoing ERCP at a time when careful utilization of resources, especially the avoidance of unnecessary hospital admissions, becomes increasingly more important.

Abdominal Pain↗
PubMed1996

The interface of endoscopic retrograde cholangiopancreatography and laparoscopic cholecystectomy.

The expanding use of laparoscopic cholecystectomy in conjunction with intraoperative cholangiography and laparoscopic common bile duct exploration has caused a reexamination of the indications of preoperative ERCP. Several studies have demonstrated the benefits of early preoperative ERCP in patients with severe gallstone pancreatitis and acute cholangitis. Those patients with only mild biochemical or radiographic abnormalities suggestive of choledocholithiasis present a clinical dilemma. The optimal diagnostic and therapeutic approach in these patients will depend on the level of expertise of both the biliary endoscopist and laparoscopist. The interface of laparoscopic cholecystectomy and ERCP will continue to evolve as surgeons become more facile with the techniques of laparoscopic common bile duct exploration. When these laparoscopic skills become widely disseminated, the use of ERCP will most likely be relegated to its well-established role in the open cholecystectomy era.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1995

Biliary tract complications after orthotopic liver transplantation. Endoscopic approach to diagnosis and therapy.

This study was undertaken to further define the role of endoscopic methods in the evaluation and treatment of biliary tract complications after liver transplantation and to determine the efficacy and safety of this approach. Fifty liver transplant patients were referred for endoscopic evaluation of a suspected biliary tract complication. Two patient groups were identified based on the indication for the endoscopic retrograde cholangiopancreatography (ERCP): Group 1 was suspected of having biliary fistula and group 2 was suspected of having bile duct obstruction. Group 1 consisted of 35 patients who developed bile peritonitis after inadvertent migration of the T-tube or intentional T-tube removal. Group 2 consisted of 15 patients who developed cholestatic hepatic chemistries in the absence of allograft rejection on liver biopsy. ERCP identified a biliary fistula at the T-tube insertion site into the bile duct in 32 (91%) group 1 patients. Twenty-six of 26 treated with a nasobiliary tube had fistula closure at a mean 5.2 days. Five of 6 treated with a stent, with or without sphincterotomy, had no leak at the time of stent removal (mean, 45 days). ERCP identified a cause for the cholestatic hepatic chemistries in 11 (73.5%) group 2 patients, including bile duct stones (n = 4), anastomotic (n = 3) or intrahepatic (n = 2) strictures, bile duct necrosis (n = 1), and hemobilia (n = 1). Five of the 5 patients undergoing endoscopic therapy were treated successfully. The endoscopic complication rate was 4% and the 30-day mortality rate was 2%. During a mean follow-up of 15 months, 94% of the patients who were treated successfully had no recurrent biliary tract disease. The results of this study suggest that ERCP is an effective modality in the evaluation of patients with suspected biliary tract complications after liver transplantation. In selected patients, endoscopic therapy obviates the need for additional surgical or percutaneous intervention.

Adult↗
PubMed1995

An n-allele model for progressive amplification in the FMR1 locus.

An n-allele model is developed for the FMR1 locus, which causes the fragile X syndrome, where n is the number of triplet repeats in the first exon. Frequencies in the general population and in index families are used to generate an n to n + delta transition matrix that predicts specific risks in satisfactory agreement with observation. However, until sequencing distinguishes between stable and unstable alleles with the same value of n, it is premature to infer whether allelic frequencies at the FMR1 locus are at equilibrium or, as some have suggested, are evolving toward higher frequencies of the pathogenic allele.

Alleles↗
PubMed1995

High dose rate endobronchial brachytherapy in the management of primary and recurrent bronchogenic malignancies.

BACKGROUND: The clinical, radiographic, and bronchoscopic records of patients treated with out-patient high dose rate (HDR) endobronchial brachytherapy were reviewed to determine its effectiveness in patients with malignant airway obstruction (with or without prior external beam radiation). In addition, quality of life and acute and chronic morbidity were evaluated. METHODS: From January 1, 1989 to June 30, 1993, 46 patients received 128 HDR endobronchial treatments employing a high activity Ir-192 source with a remote afterloader. Patients treated had a total of 22 primary and 17 recurrent bronchogenic carcinomas, 7 of which were metastatic nonpulmonary tumors. Three separate fractions of 7.0 Gy were prescribed to a depth of 1.0 cm. and given 1 week apart. Twelve patients (30%) received prior external beam irradiation (median dose, 58 Gy). RESULTS: Median follow-up for the entire group was 5 months (17.5 for surviving patients). Of the eight asymptomatic patients, five (62%) remained asymptomatic for the remainder of their lives. Of the 38 symptomatic patients, 28 (74%) had significant clinical improvement, and 12 of them remained improved for the duration of their lives. Of thirty-six (78%) patients examined for radiographic response, 25 (69%) had a partial or complete response to this treatment. In patients without prior irradiation, there was a tendency for a higher percentage of clinical and radiographic response. Two patients (4%) experienced mild, transient dysphagia, four patients developed self-limited radiation pneumonitis (9%), and three patients (7%) suffered fatal hemoptysis (all of these patients received prior or concurrent external beam radiotherapy). No factor (i.e., prior radiation therapy, number of catheters placed, surgery, or chemotherapy) predicted an increased risk of complications (P = NS). CONCLUSIONS: Outpatient HDR endobronchial brachytherapy is effective in both preventing and relieving endobronchial obstruction in patients with or without prior irradiation, recurrent lesions, or metastatic nonpulmonary disease. A significant proportion of patients can be rendered asymptomatic for the duration of their lives, hence were provided with improved quality of life. These treatments are well tolerated and safe, and result in minimal long term morbidity.

Aged↗