Application of the research electronic data capture (REDCap) system in a low- and middle income country- experiences, lessons, and challenges

The challenges of reliably collecting, storing, organizing, and analyzing research data are critical in low- and middle-income countries (LMICs), particularly in Sub-Saharan Africa where several healthcare and biomedical research organizations have limited data infrastructure. The Research Electronic Data Capture (REDCap) System has been widely used by many institutions and hospitals in the USA for data collection, entry, and management and could help solve this problem. This study reports on the experiences, challenges, and lessons learned from establishing and applying REDCap for a large US-Nigeria research partnership that includes two sites in Nigeria, (the College of Medicine of the University of Lagos (CMUL) and Jos University Teaching Hospital (JUTH)) and Northwestern University (NU) in Chicago, Illinois in the United States. The largest challenges to this implementation were significant technical obstacles: the lack of REDCap-trained personnel, transient electrical power supply, and slow/intermittent internet connectivity. However, asynchronous communication and on-site hands-on collaboration between the Nigerian sites and NU led to the successful installation and configuration of REDCap to meet the needs of the Nigerian sites. An example of one lesson learned is the use of Virtual Private Network (VPN) as a solution to poor internet connectivity at one of the sites, and its adoption is underway at the other. Virtual Private Servers (VPS) or shared online hosting were also evaluated and offer alternative solutions. Installing and using REDCap in LMIC institutions for research data management is feasible; however, planning for trained personnel and addressing electrical and internet infrastructural requirements are essential to optimize its use. Building this fundamental research capacity within LMICs across Africa could substantially enhance the potential for more cross-institutional and cross-country collaboration in future research endeavors.

Estimation of genetic parameters for birth weight, preweaning mortality, and hot carcass weight of crossbred pigs

Genetic parameters for birth weight (BWT), preweaning mortality (PWM), and HCW were estimated for a crossbred pig population to determine if BWT could be used as an early predictor for later performances. Sire genetic effects for those traits were estimated to determine if early selection of purebred sires used in crossbreeding could be improved. Data were recorded from 1 commercial farm between 2008 and 2010. Data were from 24,376 crossbred pigs from Duroc sires and crossbred Large White × Landrace dams and included 24,376 BWT and PWM records and 13,029 HCW records. For the analysis, PWM was considered as a binary trait (0 for live or 1 for dead piglet at weaning). A multitrait threshold-linear animal model was used, with animal effect divided into sire genetic and dam effects; the dam effects included both genetic and environmental variation due to the absence of pedigree information for crossbred dams. Fixed effects were sex and parity for all traits, contemporary groups for BWT and HCW, and age at slaughter as a linear covariable for HCW. Random effects were sire additive genetic, dam, litter, and residual effects for all traits and contemporary group for PWM. Heritability estimates were 0.04 for BWT, 0.02 for PWM, and 0.12 for HCW. The ratio between sire genetic and total estimated variances was 0.01 for BWT and PWM and 0.03 for HCW. Dam and litter variances explained, respectively, 14% and 15% of total variance for BWT, 2% and 10% for PWM, and 3% and 8% for HCW. Genetic correlations were -0.52 between BWT and PWM, 0.55 between BWT and HCW, and -0.13 between PWM and HCW. Selection of purebred sires for higher BWT of crossbreds may slightly improve survival until weaning and final market weight at the commercial level.

Genetic analyses of stillbirth in relation to litter size using random regression models

Estimates of genetic parameters for number of stillborns (NSB) in relation to litter size (LS) were obtained with random regression models (RRM). Data were collected from 4 purebred Duroc nucleus farms between 2004 and 2008. Two data sets with 6,575 litters for the first parity (P1) and 6,259 litters for the second to fifth parity (P2-5) with a total of 8,217 and 5,066 animals in the pedigree were analyzed separately. Number of stillborns was studied as a trait on sow level. Fixed effects were contemporary groups (farm-year-season) and fixed cubic regression coefficients on LS with Legendre polynomials. Models for P2-5 included the fixed effect of parity. Random effects were additive genetic effects for both data sets with permanent environmental effects included for P2-5. Random effects modeled with Legendre polynomials (RRM-L), linear splines (RRM-S), and degree 0 B-splines (RRM-BS) with regressions on LS were used. For P1, the order of polynomial, the number of knots, and the number of intervals used for respective models were quadratic, 3, and 3, respectively. For P2-5, the same parameters were linear, 2, and 2, respectively. Heterogeneous residual variances were considered in the models. For P1, estimates of heritability were 12 to 15%, 5 to 6%, and 6 to 7% in LS 5, 9, and 13, respectively. For P2-5, estimates were 15 to 17%, 4 to 5%, and 4 to 6% in LS 6, 9, and 12, respectively. For P1, average estimates of genetic correlations between LS 5 to 9, 5 to 13, and 9 to 13 were 0.53, -0.29, and 0.65, respectively. For P2-5, same estimates averaged for RRM-L and RRM-S were 0.75, -0.21, and 0.50, respectively. For RRM-BS with 2 intervals, the correlation was 0.66 between LS 5 to 7 and 8 to 13. Parameters obtained by 3 RRM revealed the nonlinear relationship between additive genetic effect of NSB and the environmental deviation of LS. The negative correlations between the 2 extreme LS might possibly indicate different genetic bases on incidence of stillbirth.

Unusual mammography findings of patients with ductal carcinoma in situ (DCIS) of the breast

Abstract The early detection of carcinoma is the highlight of mammography. We present two patients with pathological diagnosis of DCIS with unusual mammographic findings for which one needs to have a higher index of suspicion. The first patient presented with multifocal disease requiring biopsy of all visible lesions and the second patient (twenty four years old) presented with segmental distribution of calcifications, which may have been missed had a single-view baseline mammogram not been done.

Histo-pathological correlation of BI-RADS 4 lesions on mammography with emphasis on microcalcification patterns

A retrospective study of 20 patients with Breast Imaging Reporting and Data System (BI-RADS) 4 lesions was undertaken. These patients were classified as BI-RADS 4 lesions due to presence of a mass (clinical or on mammography), architectural distortion and microcalcifications (MC). In some patients, the pattern of MC was benign but there were other features that were suspicious of malignancy. A comparison was made with the histological diagnosis in order to compare the radiological appearance of benign and malignant microcalcification patterns with the final histology. The study design included retrospective analysis of patients with MC on digital mammography who underwent biopsy. An analysis of the histology was then undertaken. Other factors in the history and physical examination were also considered. Results showed that although the study was not statistically significant due to limited study population, interesting trends are determined in assessing calcification patterns using the Breast Imaging Reporting and Data System (BI-RADS) classification system, since some lesions that were thought to have benign calcification patterns were actually malignant and vice versa. Further study in this field is required.

Genetic correlations between two strains of Durocs and crossbreds from differing production environments for slaughter traits

The aim of this study was to estimate the genetic correlations between 2 purebred Duroc pig populations (P1 and P2) and their terminal crossbreds [C1 = P1 x (Landrace x Large White) and C2 = P2 x (Landrace x Large White)] raised in different production environments. The traits analyzed were backfat (BF), muscle depth (MD), BW at slaughter (WGT), and weight per day of age (WDA). Data sets from P1, P2, C1, and C2 included 26,674, 8,266, 16,806, and 12,350 animals, respectively. Two-trait models (nucleus and commercial crossbreds) for each group included fixed (contemporary group, sex, weight, and age), random additive (animal for P1 and P2 and sire for C1 and C2), random litter, and random dam (C1 and C2 only) effects. Heritability estimates (+/-SE) for BF were 0.46 +/- 0.04, 0.38 +/- 0.02, 0.32 +/- 0.02, and 0.33 +/- 0.02 for P1, P2, C1, and C2, respectively. Heritability estimates for MD were 0.31 +/- 0.01, 0.23 +/- 0.02, 0.19 +/- 0.01, and 0.12 +/- 0.01 for P1, P2, C1, and C2, respectively. The estimates for WGT and WDA were 0.31 +/- 0.01, 0.21 +/- 0.02, 0.16 +/- 0.01, and 0.18 +/- 0.01 and 0.32 +/- 0.01, 0.22 +/- 0.02, 0.16 +/- 0.01, and 0.19 +/- 0.01, respectively. Genetic correlations between purebreds and crossbreds for BF were 0.83 +/- 0.09 (P1 x C1) and 0.89 +/- 0.05 (P2 x C2), for MD 0.78 +/- 0.05 (P1 x C1) and 0.80 +/- 0.08 (P2 x C2). For WGT and WDA, the correlations were 0.53 +/- 0.08 (P1 x C1), 0.80 +/- 0.10 (P2 x C2), and 0.60 +/- 0.07 (P1 x C1) and 0.79 +/- 0.09 (P2 x C2), respectively. (Co)variances in crossbreds were adjusted to a live BW scale. Compared with purebreds, the genetic variances in crossbreds were lower, and the residual variances were greater. Sire variances in crossbreds were approximately 20 to 30% of the animal variances in purebreds for BF and MD but were 13 to 25% for WGT and WDA. The efficiency of purebred selection on crossbreds, assessed by EBV prediction weights, ranged from 0.43 to 0.91 for line 1 and 0.70 to 0.92 for line 2. When nucleus and commercial environments differ substantially, the efficiency of selection varies by line and traits, and selection strategies that include crossbred data from typical production environments may therefore be desirable.

Is the routine use of intravenous contrast justified in the work-up of adult-onset seizure patients with a normal pre-contrast brain scan?

The indications for the administration of intravenous contrast media to adult patients presenting with first time seizures and a normal pre-contrast study are not clear. A retrospective audit of such patients was done and compared with the post-contrast study. In our study sample of 205 patients all the post-contrast scans were reported as normal, indicating that contrast can be omitted if the precontrast study was normal. This only applies to computed tomography, and magnetic resonance imaging was not included.

Transjugular intrahepatic portosystemic shunting is not superior to endoscopic variceal band ligation for prevention of variceal rebleeding in cirrhotic patients: a randomized, controlled trial

BACKGROUND

The aim of the present study was to compare the transjugular intrahepatic portosystemic shunt (TIPS) with variceal band ligation (VBL) in the prophylaxis of variceal rebleeding in patients with cirrhosis of the liver.

METHODS

Fifty-four cirrhotic patients (21 Child-Pugh class A, 27 class B, 6 class C) were randomized to TIPS (n = 28) or VBL (n = 26) within 2 months after control of esophageal variceal hemorrhage. Statistical analysis was performed on the intention-to-treat principle.

RESULTS

Mean follow-up was 2 years. Mortality risk at 1 and 2 years of follow-up was 7.8% +/- 5.3% and 19.9% +/- 8.8% in the TIPS group and 16.5% +/- 7.6% and 16.5% +/- 7.6% in the VBL group, respectively (n.s.); actuarial probability of remaining free from rebleeding was 83.7% +/- 77.4% and 71.4% +/- 10.4% in the TIPS group and 83.9% +/- 7.3% and 78.1% +/- 8.8% in the VBL group at 1 and 2 years, respectively (n.s.). Hepatic encephalopathy within 1 month after randomization was observed in 2 patients in the TIPS group and in 1 in the VBL group.

CONCLUSION

TIPS is not superior to VBL in the prevention of variceal rebleeding. Furthermore, similar mortality rates in patients treated with TIPS or VBL negate TIPS as the preferred strategy for prevention of variceal rebleeding.

Estimating the cost of developmental and behavioral screening of preschool children in general pediatric practice

OBJECTIVE

Despite increased recognition of the importance of development and growth of young children, formal developmental and behavioral screening often is not included in general pediatric practice. Barriers to the provision of developmental and behavioral screening are considerable; among them are the need for specialized training and uncertain reimbursement. This article develops a model for estimating the cost of providing pediatric developmental and behavioral screening that can be scaled to reflect a pediatric practice's patient population and choice of screening offered.

METHODS

The framework for our scaleable cost model was drawn from work done in estimating the Resource-Based Relative Value Scale (RBRVS). RBRVS provides estimates of the work effort involved in the provision of health care services for individual Current Procedural Terminology codes. The American Academy of Pediatrics has assigned descriptions of pediatric services, including developmental and behavioral screening, to the Current Procedural Terminology codes originally created for adult health care services. The cost of conducting a screen was calculated as a function of the time and staff required and was loaded for practice costs using the RBRVS valuation. The cost of the follow-up consultation was calculated as a function of the time and staff required and the number of relative value units assigned in the RBRVS scale.

RESULTS

The practice cost of providing developmental and behavioral screening is driven primarily by the time and staff required to conduct and evaluate the screens. Administration costs are lowest for parent-administered developmental screens ($0 if no assistance is required) and highest ($67) for lengthy, pediatric provider-administered screens, such as the Neonatal Behavioral Assessment Scale. The costs of 3 different groups of developmental and behavioral screening are estimated. The estimated per-member per-month cost per 0- to 3-year-old child ranges from $4 to >$7 in our 3 examples.

CONCLUSIONS

Cost remains a significant barrier to greater provision of formal developmental and behavioral screening. Our scaleable cost model may be adjusted for a given practice to account for the overall level of developmental risk. The model also provides an estimate of the time and cost of providing new screening services. This model allows pediatric practices to select the mix of developmental screens most appropriate for their particular patient population at an acceptable cost.

[TIPS in patients with therapy refractory ascites and kidney dysfunction]

BACKGROUND

A transjugular intrahepatic portosystemic shunt (TIPS) is increasingly being used for treatment of patients with refractory ascites and renal failure. The aim of this study was to investigate the effects of TIPS in patients with refractory ascites and organic or functional renal impairment.

METHODS

A TIPS was placed for refractory or intractable ascites in 10 consecutive patients with liver cirrhosis and impaired renal function (serum creatinine > 1.5 mg/100 ml). Four of them had organic kidney disorders. The other six patients had functional renal impairment due to the underlying liver disease.

RESULTS

TIPS was effective in reducing ascites in 8 of 10 patients, including all patients with organic renal disease. Furthermore, after TIPS the renal function improved in all patients. Serum creatinine and serum urea levels decreased significantly from 1.8 to 1.5 mg/100 ml (p < 0.05) and from 107 to 78 mg/100 ml respectively.

CONCLUSION

TIPS may be useful in patients with functional and in patients with organic renal disease, resulting in improvement of ascites and renal function.

Extracorporeal shock wave lithotripsy for clearance of bile duct stones resistant to endoscopic extraction

BACKGROUND

Endoscopic extraction of bile duct stones after sphincterotomy has a success rate of up to 95%. Failures occur in patients with extremely large stones, intrahepatic stones, and bile duct strictures. This study examined the efficacy and the safety of extracorporeal shock-wave lithotripsy in a large cohort of patients in whom routine endoscopic measures including mechanical lithotripsy had failed to extract bile duct stones.

METHODS

Out of 1587 consecutive patients, endoscopic stone extraction including mechanical lithotripsy was unsuccessful in 313 (20%). These 313 patients (64% women, median age, 73 years) underwent high-energy extracorporeal shock-wave lithotripsy. Stone targeting was performed fluoroscopically (99%) or by ultrasonography (1%).

RESULTS

Complete clearance of bile duct calculi was achieved in 281 (90%) patients. In 80% of the patients, the fragments were extracted endoscopically after shock-wave therapy; spontaneous passage was observed in 10%. For patients with complete clearance compared with those without there were no differences with regard to size or number of the stones, intrahepatic or extrahepatic stone location, presence or absence of bile duct strictures, or type of lithotripter. Cholangitis (n = 4) and acute cholecystitis (n = 1) were the rare adverse effects.

CONCLUSIONS

In patients with bile duct calculi that are difficult to extract endoscopically, high-energy extracorporeal shock-wave lithotripsy is a safe and effective therapy regardless of stone size, stone location, or the presence of bile duct stricture.

A comparison of paracentesis and transjugular intrahepatic portosystemic shunting in patients with ascites

BACKGROUND

In patients with cirrhosis and ascites, creation of a transjugular intrahepatic portosystemic shunt may reduce the ascites and improve renal function. However, the benefit of this procedure as compared with that of large-volume paracentesis is uncertain.

METHODS

We randomly assigned 60 patients with cirrhosis and refractory or recurrent ascites (Child-Pugh class B in 42 patients and class C in 18 patients) to treatment with a transjugular shunt (29 patients) or large-volume paracentesis (31 patients). The mean (+/-SD) duration of follow-up was 45+/-16 months among those assigned to shunting and 44+/-18 months among those assigned to paracentesis. The primary outcome was survival without liver transplantation.

RESULTS

Among the patients in the shunt group, 15 died and 1 underwent liver transplantation during the study period, as compared with 23 patients and 2 patients, respectively, in the paracentesis group. The probability of survival without liver transplantation was 69 percent at one year and 58 percent at two years in the shunt group, as compared with 52 percent and 32 percent in the paracentesis group (P=0.11 for the overall comparison, by the log-rank test). In a multivariate analysis, treatment with transjugular shunting was independently associated with survival without the need for transplantation (P=0.02). At three months, 61 percent of the patients in the shunt group and 18 percent of those in the paracentesis group had no ascites (P=0.006). The frequency of hepatic encephalopathy was similar in the two groups. Of the patients assigned to paracentesis in whom this procedure was unsuccessful, 10 received a transjugular shunt a mean of 5.5+/-4 months after randomization; 4 had a response to this rescue treatment.

CONCLUSIONS

In comparison with large-volume paracentesis, the creation of a transjugular intrahepatic portosystemic shunt can improve the chance of survival without liver transplantation in patients with refractory or recurrent ascites.

Accidental exposures to blood and other body fluids in a large academic medical center

Healthcare workers' and students' exposures to blood-borne pathogens during a 1-year period (1997) at a large university academic medical center were analyzed. The university health manages the Blood-Borne Pathogen Post-Exposure Control Program at the university and treats all reported exposures of students, faculty, and staff. Comparative exposure rates for all categories of healthcare workers, the work site where injuries occurred, and the circumstances involved in 298 exposure incidents are outlined. A standardized postexposure prophylaxis protocol provides for definition of the health status of all known source patients and assessment of the potential need for treatment of the exposed clinician. Implications of the study for focusing on improvements in training healthcare workers in proper procedures and the use of personal protective equipment in dealing with blood-borne pathogens are discussed.

Detection of colonic dysplasia by light-induced fluorescence endoscopy: a pilot study

Light-induced fluorescence endoscopy (LIFE) has been shown to differentiate between normal mucosa and dysplastic lesions, and dysplastic lesions of the colon occult to routine white-light colonoscopy may thus be visualized by LIFE. We compared the sensitivity and specificity of LIFE to routine white-light colonoscopy in patients with colonic dysplasia. In a pilot study 20 patients with colonic adenoma, inflammatory bowel disease, or with a history of colon cancer were screened for colonic dysplasia during routine colonoscopy. Forty-two sites of mucosal abnormalities regarded as suspicious for dysplasia during white-light colonoscopy were additionally examined with a prototype LIFE system. Biopsies were taken from all 42 colonic sites. The LIFE images were classified as positive or negative for dysplasia. Sensitivity and specificity were calculated by correlating positive and negative findings to the histopathological results. Histopathology detected 21 adenomas with low-grade dysplasia and one with high-grade dysplasia. All dysplastic lesions were found by routine white-light endoscopy. The specificity of conventional white-light endoscopy was 80%. Of the 22 dysplastic lesions 20 were detected by LIFE (sensitivity 91%). The specificity of LIFE was 90% (two false-positive results). LIFE combined with conventional endoscopy may thus improve the detection of colonic dysplasia.

Transjugular intrahepatic portosystemic shunt (TIPS) for variceal bleeding in portal hypertension: comparison of emergency and elective interventions

Nonsurgical reduction of portal hypertension by transjugular intrahepatic portosystemic shunt (TIPS) is widely used for prevention of variceal rebleeding (elective TIPS). Information is limited about the value of emergency TIPS for acute variceal bleeding unresponsive to endoscopic and drug therapy. The aim of the present study was therefore to determine whether the effects and complications differ between emergency and elective TIPS in patients with cirrhosis of the liver. TIPS was performed in 11 patients with acute variceal bleeding unresponsive to endoscopic treatment and 22 patients in stable condition after an episode of variceal bleeding. Clinical examination, blood sampling, Doppler sonography of TIPS flow, and upper gastrointestinal endoscopy were performed at days 1, 7, and 30 and at three-month intervals after TIPS. Mean follow-up was 549 (1-987) days. Bleeding was controlled by emergency TIPS in 10/11 patients. Probability of survival was not different after emergency and elective TIPS (0.73 vs 0.84 at one year). Early rebleeding (< or =2 weeks) occurred more often after emergency TIPS (3/11 vs 0/22 patients; P = 0.03), but there was no significant difference in late rebleeding. Occlusion of TIPS was more frequent after emergency TIPS. Occurrence of TIPS stenoses was identical in both groups (4/11 vs 8/22). De novo or deterioration of preexisting hepatic encephalopathy was similar (18% vs 24%; NS). It is concluded that TIPS is effective for control of acute variceal bleeding unresponsive to endoscopic and drug treatment. Early rebleeding and stent occlusion occurred more often after emergency TIPS. Late rebleeding, complications, and long-term survival did not differ from elective TIPS.

Renal effects of transjugular intrahepatic portosystemic shunt in cirrhosis: comparison of patients with ascites, with refractory ascites, or without ascites

Renal effects of the transjugular intrahepatic portosystemic shunt (TIPS) were compared in 6 patients without ascites (group 1), 11 patients with ascites responding to diuretic treatment (group 2), and 6 patients with refractory ascites (group 3). Seven days after insertion of TIPS, 24-hour urinary sodium excretion had increased in patients with ascites: 113 +/- 16 mmol to 170 +/- 30 mmol (P = .012) in group 2, and 22 +/- 8 mmol to 77 +/- 27 mmol (P = .050) in group 3. In group 3, fractional sodium excretion tended to increase from 0.26% +/- 0.14% to 0.62% +/- 18% (P = .081). The relative increase of urinary sodium excretion (to 444% +/- 122%) and fractional sodium excretion (to 413% +/- 127%) in group 3 was significantly (P < .05) higher than in group 1 and group 2, respectively. Creatinine clearance and 24-hour urinary volume were not significantly changed in either group. Patients with Child-Pugh class C had a more pronounced effect of TIPS on urinary sodium excretion (increase to 396% +/- 115% vs. 139% +/- 15%; P = .066) and on fractional sodium excretion (increase to 415% +/- 103% vs. 94% +/- 15%; P = .020) than patients with less-severe liver disease. Fractional sodium excretion of less than 0.35% before TIPS was found to be an indicator of renal response to TIPS. The effect of TIPS on urinary sodium excretion and on fractional sodium excretion was related to the patients' Child-Pugh score (r = .55; P = .007 and r = .68; P = .001, respectively) and inversely to their fractional sodium excretion (r = -.44; P = .047 and r = -.54; P = .012, respectively) before TIPS. These data demonstrate that TIPS affects renal sodium handling in patients with ascites, particularly in patients with refractory ascites. Severity of liver disease and fractional sodium excretion before TIPS are parameters to predict the extent of the renal response.

A scientific relational database combined with a report generator for endoscopy in networks: EndoNet

BACKGROUND AND STUDY AIMS

The flexibility required in academic endoscopy units is not provided by the available database systems. In a project involving substantial cooperation between endoscopists and computer scientists, we have developed an adaptable database, combined with a report generator embedded in the hospital's intranet.

PATIENTS AND METHODS

Six workstations in different areas of the hospital were clustered with a UNIX operating system to implement multi-user capability and access control. A relational database was used to design an application appropriate to the specific needs of the endoscopy unit in a teaching hospital engaged in scientific research. Both the terminology used in standardized endoscopy nomenclature and a free text block facility were included. A graphical user interface was developed to assemble pertinent data, generate the reports, and supervise the database.

RESULTS

A total of 4936 examinations including 2988 patients were entered consecutively during continuous routine operation of the system. Complete report generation required five minutes (median; range 1-9 minutes). Both structured items and free text were used in all the reports. Querying of the database was possible, concerning matters such as the need for repeated endoscopic therapy in acute gastrointestinal bleeding (4%), the search for Helicobacter pylori in appropriate patients (64%), the rate of accidental pancreatic duct visualization in endoscopic retrograde cholangiography (24%), and links between examinations and active trials (2%). Indicating improved report quality, the number and the diameter of esophageal varices in patients with varices were more frequently reported with the new report system than with previous typed reports (P<0.001). An anonymous questionnaire revealed that the readability of the computer-generated reports was better than that of the previous typewritten reports (P=0.01).

CONCLUSIONS

This report describes the creation of a database application and a report generator meeting the needs of scientific and routine use, and the successful application of this system in an academic endoscopy unit.

Experiences with novel techniques for reduction of stent flow in transjugular intrahepatic portosystemic shunts

The transjugular intrahepatic portosystemic shunt (TIPS) may deteriorate liver function and can cause encephalopathy in patients with cirrhosis of the liver. Then reduction of TIPS flow may be required. We here report several attempts to reduce shunt flow in TIPS-induced encephalopathy or liver function impairment with novel techniques. Three patients with cirrhosis of the liver were investigated: Two with severe recurrent encephalopathy and one with impaired liver function following TIPS insertion. Insertion of a reducing stent was ineffective to decrease shunt flow velocity in one patient with severe coagulopathy. Sufficient reduction of shunt flow was achieved by embolizing the space around the hourglass waist of the reducing stent with an occlusion emulsion. Insertion of a conventional stent within the preexisting TIPS with or without additional embolization reduced TIPS flow in the other patients. After reduction of shunt flow encephalopathy improved and liver function returned to the level before TIPS, respectively. During follow-up no occlusion of TIPS was observed. Thus, reduction of shunt flow velocity can be achieved by insertion of an additional stent into a curve-shaped TIPS. Embolization can be helpful to decrease TIPS flow, particularly in patients with severe coagulopathy. Reduction of TIPS flow can correct TIPS-induced complications.

Breath-hold MR cholangiography with snapshot techniques: prospective comparison with endoscopic retrograde cholangiography

PURPOSE

To compare findings with magnetic resonance (MR) cholangiography with rapid acquisition with relaxation enhancement (RARE) and half-Fourier acquisition with single-shot turbo spin-echo (hereafter, half Fourier RARE) snapshot imaging techniques to those with endoscopic retrograde cholangiography (ERC).

MATERIALS AND METHODS

Heavily T2-weighted thick-section (RARE) and thin-section (half-Fourier RARE) MR cholangiography were performed prospectively, on a 1.5-T imager, in the biliary tree of 61 consecutive patients before ERC. Findings at ERC were considered the standard of reference. The radiologist and endoscopist were blinded to each other's report. On- and off-site MR cholangiographic readings were performed to detect stones (n = 24), biliary dilatation (n = 34), or stenosis (n = 36).

RESULTS

The sensitivity and specificity of MR cholangiography, respectively, calculated on a lesion-by-lesion basis, were 92.3% and 95.8% for cholangiolithiasis, 94.1% and 92.6% for duct dilatation, and 88.8% and 84.0% for stenosis. With snapshot MR cholangiography, on a patient-by-patient basis, differentiation between normal (n = 15) and abnormal (n = 46) results yielded a sensitivity of 92.4%, a specificity of 83.4%, and a positive predictive value of 95.6%. Pitfalls were caused by flow artifacts, compression by vessels, and low contrast between calculi and surrounding parenchyma.

CONCLUSION

Snapshot MR cholangiography allowed noninvasive, accurate detection of biliary stones, strictures, and dilatation similar to that with ERC. Discrepancies regarding low-grade dilatation and strictures had no clinical relevance at retrospective review.

Health insurance for low-income working families. Effect on the provision of immunizations to preschool-age children

BACKGROUND

The out-of-pocket cost for immunizations is a cause for referral to public health department clinics and is associated with delayed immunization. In 1991, New York State started Child Health Plus (CHPlus), an insurance program that covers ambulatory care and immunization services for children of families earning less than 222% of the poverty level.

OBJECTIVE

To determine the effect of CHPlus on the provision of immunizations.

DESIGN

A before-and-after design was used to compare the year immediately before enrollment in CHPlus with the first year after enrollment in CHPlus. A mixed-model analysis of variance was used to control for the effects of age.

SETTING

All area primary care practices (n = 164) and public health department clinics (n = 6).

SUBJECTS

Children (n = 1730) younger than 6 years who were enrolled in CHPlus.

MAIN OUTCOME MEASURES

Number of immunization visits; types of providers (public health department clinics or primary care providers [pediatricians and family physicians]); and series-complete immunization coverage, including the diphtheria toxoid, tetanus toxoid, and pertussis vaccine, the oral poliovirus vaccine, and the measles, mumps, and rubella vaccine.

RESULTS

The average age of the children was 37.7 months, 85% were white, 50% had been uninsured for immunizations before enrollment in CHPlus, and 16% previously received Medicaid. For infants, CHPlus decreased immunization visits to public health department clinics by 37% (from 0.14 to 0.09 visits per child, P = .009), increased immunization visits to primary care providers' offices by 15% (from 2.3 to 2.7 visits per child, P = .001), and increased immunization coverage by 7% (from 76% to 83%, P = .03). For children aged 1 to 5 years, CHPlus decreased visits to public health department clinics by 67% (from 0.06 to 0.02 visits per child, P < .001), increased visits to primary care providers' offices by 27% (from 0.46 to 0.59 visits per child, P < .001), and increased immunization coverage by 5% (from 83% to 88%, P < .001). The effects were greatest among previously uninsured children and among those with a gap in insurance coverage that was longer than 6 months.

CONCLUSIONS

Insurance coverage for low-income working families resulted in a shift in the provision of immunizations from the health department to primary care providers and in increased immunization coverage.

Safety and efficacy of repeated shockwave lithotripsy of gallstones with and without adjuvant bile acid therapy

BACKGROUND & AIMS

The value of adjuvant bile acid dissolution therapy after extracorporeal shockwave lithotripsy (ESWL) of gallbladder stones is under debate. A double-blind, randomized, multicenter trial was conducted to determine the safety and efficacy of repeated ESWL with and without adjuvant bile acid therapy.

METHODS

At five centers, 153 patients with gallstones and good gallbladder emptying were randomized to undergo up to six high-energy lithotripsy sessions combined with ursodeoxycholic acid (UDCA, 750 mg/day; n = 77) or placebo (n = 76).

RESULTS

Six months after the initial treatment, 77% of patients with small single stones (< or = 20 mm in diameter), 60% with large single stones (> 20 mm in diameter), and 41% with multiple stones were free of stones. Administration of UDCA had no effect on stone disappearance in the whole study group but tended to improve stone disappearance rates in patients with large single stones and tended to decrease biliary adverse effects in patients with multiple stones.

CONCLUSIONS

Repeated high-energy ESWL without adjuvant bile acid therapy represents a safe and effective treatment in patients with small single stones and good gallbladder emptying. In patients with large single stones and multiple stones, adjuvant bile acid therapy may be beneficial.

Gallbladder emptying and gallstone formation: a prospective study on gallstone recurrence

BACKGROUND & AIMS

Gallbladder emptying is reduced in many patients with cholesterol gallstones. To clarify the role of impaired gallbladder motility in recurrent gallstone disease, the effect of gallbladder emptying on the formation of recurrent stones was studied prospectively.

METHODS

In 54 consecutive patients with single radiolucent gallbladder stones, postprandial gallbladder emptying was assessed sonographically before lithotripsy and 1.8 +/- 0.1 years (mean +/- SE) after gallstone disappearance. Patients were followed up for gallstone recurrence for 0.6-4.1 years (median, 2.6 years).

RESULTS

After gallstone disappearance, gallbladder fasting volume (33.7 +/- 3.4 vs. 27.8 +/- 3.0 mL; P = 0.007) and residual volume (12.6 +/- 1.9 vs. 9.7 +/- 1.3 mL; P = 0.010) decreased, whereas the ejection fraction remained unchanged. However, gallbladder volume did not differ whether initial or recurrent stones were present. Gallbladder emptying was more impaired in patients with than patients without later recurrence (47% +/- 5% vs. 63% +/- 2%; P = 0.001). Cox analysis showed that gallbladder emptying was an independent determinant of the risk of gallstone recurrence (P = 0.002). Within 3 years, recurrent stones formed in 53% (actuarial analysis) of patients with an ejection fraction of < 60% but in only 13% of patients with an ejection fraction of > or = 60%.

CONCLUSIONS

Gallbladder emptying is an important factor in the formation of recurrent gallstones.

Evaluation of gallbladder volume and emptying with a novel three-dimensional ultrasound system: comparison with the sum-of-cylinders and the ellipsoid methods

To overcome the geometrical limitations of current methods to calculate gallbladder volume from two-dimensional sonographic images, we evaluated the accuracy and precision of a novel three-dimensional ultrasound system (3D). In vitro accuracy of 3D volumetry (10 mL to 55 mL) was 98.1 +/- 7.1% (mean+/-SD) with a mean difference of 0.7 mL between the measured and the true volume (p < 0.003). Compared with the sum-of-cylinders (SC) and the ellipsoid (EL) methods, 3D was characterized by a significantly smaller systematic bias and closer limits of agreement with the true volume. The variation coefficient was smallest with 3D (2.4%, p < 0.02) and largest with EL (4.2%). In vivo, gallbladder volumes were on average 1.4 mL (9%) smaller with 3D than with SC (p < 0.0001) and 2.4 mL (14%) larger with EL than with SC (p < 0.0001). 3D ultrasonography accurately measures gallbladder volume and emptying.

Simvastatin added to ursodeoxycholic acid does not enhance disappearance of gallstone fragments after shock wave therapy

Inhibitors of the HMG-CoA reductase have been shown to further reduce the biliary cholesterol saturation in patients treated with oral bile acids for cholesterol gallbladder stones. It was the aim of our study to evaluate the efficacy of simvastatin in addition to ursodeoxycholic acid in the dissolution of gallstone fragments after shock wave lithotripsy and adjuvant bile acid dissolution therapy. Eighteen patients with a single radiolucent gallbladder stone and a serum cholesterol of more than 250 mg/dl were randomly assigned to receive either ursodeoxycholic acid alone (750 mg per day, group A, n = 9) or in combination with simvastatin (20 mg per day, group B, n = 9) for the dissolution of the gallstone fragments generated by extracorporeal shock wave lithotripsy. The two groups were well matched regarding their baseline characteristics. At the primary end point of the study 6 months after lithotripsy, there was no difference between the groups in the rate of gallstone disappearance with 4 of 9 patients being stone free in each group. As evaluated by life table analysis, even further follow-up showed no significant difference between the groups (P = 0.8). In group B, serum cholesterol levels decreased by 22% at 3 months (P = 0.01 vs. baseline) and by 24% at six months (P = 0.02) during treatment while no significant change was observed in group A. With both regiments, no adverse effects were observed. While simvastatin added to ursodeoxycholic acid resulted in a decrease of elevated serum cholesterol levels in gallstone patients, it did not enhance stone disappearance after shock wave lithotripsy and adjuvant bile acid dissolution therapy.

Gallstone recurrence after direct contact dissolution with methyl tert-butyl ether

To determine the rate and characteristics of gallstone recurrence after direct contact dissolution with methyl tert-butyl ether, 60 consecutive patients were followed for up to 4.5 years (median 2.2 years) after complete disappearance of all stone residues and debris and cessation of adjuvant bile acid therapy. Initial gallstones had been multiple in all but four patients. Twenty-eight of the 60 patients developed recurrent gallstones. The cumulative risk of gallstone recurrence (actuarial analysis) was 23 +/- 6%, 34 +/- 7%, 55 +/- 8%, and 70 +/- 9% at one, two, three, and four years, respectively. The recurrent stones were usually multiple and small (6 +/- 4 mm). Gallstone recurrence was associated with recurrent biliary pain in two patients, one of whom developed acute cholecystitis. Recurrent stones were cleared completely by bile acid medication with or without shock-wave lithotripsy in 61 +/- 15% of patients at one year (actuarial analysis). In conclusion, gallstone recurrence after successful contact dissolution of multiple stones with methyl tert-butyl ether has to be expected in a high percentage of patients. Most patients, however, remain free of biliary pain during long-term follow-up.

Dormia baskets impacted in the bile duct: release by extracorporeal shock-wave lithotripsy

BACKGROUND AND STUDY AIMS

Endoscopic extraction of bile duct stones may be complicated by impaction of the Dormia basket with captured stones, or rupture of the traction wire of the basket during mechanical lithotripsy. In an attempt to release impacted baskets by nonoperative means, we studied the efficacy of extracorporeal shock-wave lithotripsy in this dangerous clinical situation.

PATIENTS AND METHODS

Fourteen extracorporeal shock-wave treatments were performed in 12 consecutive patients (eight women and four men; mean age 73.2 +/- 13.2 years, range 46-86 years) with an electrohydraulic shock-wave lithotriptor, using fluoroscopy (n = 13) or ultrasound (n = 1) for targeting. A total of 1845 +/- 334 (mean +/- SD) shock-wave discharges at a voltage of 22 +/- 4 kV were delivered per treatment. Nine treatment sessions (64%) were performed while patients were under general anesthesia. An attempt to extract the Dormia basket was made after disintegration of the captured stone had been confirmed by fluoroscopy.

RESULTS

It was possible to remove the Dormia basket by nonsurgical means in 11 of the 12 patients (92%) after one treatment session, and after three treatment sessions in the remaining patient. Thus, disintegration of the stones allowed extraction of the Dormia basket in all patients. None of the patients needed surgical intervention. All patients were rendered free of bile duct stones after extracorporeal shock-wave lithotripsy and subsequent endoscopic removal of the fragments. No adverse effects of shock-wave therapy with subsequent extraction of the Dormia baskets were observed.

CONCLUSION

Shock-wave therapy represents a primary nonsurgical therapeutic option in patients with either impacted Dormia baskets or broken devices which cannot be extracted by endoscopic means.

Gallbladder emptying determines early gallstone clearance after shock-wave lithotripsy

BACKGROUND/AIMS

Disappearance of gallbladder stones after shock-wave lithotripsy combined with bile acid therapy depends on mechanical evacuation and dissolution of fragments. Many patients with gallstones have impaired gallbladder emptying and may show delayed stone clearance after lithotripsy.

METHODS

The effect of gallbladder emptying on gallstone clearance after lithotripsy was prospectively studied in 57 patients with one radiolucent gallbladder stone < or = 20 mm. Gallbladder emptying was assessed sonographically before and after 2 weeks of ursodeoxycholic acid (UDCA) treatment.

RESULTS

UDCA increased gallbladder fasting and residual volume and decreased ejection rate but did not affect ejection fraction. Patients with an ejection fraction > 60% achieved complete gallstone clearance after lithotripsy in a higher percentage than patients with smaller ejection fractions (1 month, 31% vs. 7%, P = 0.022; 2 months, 55% vs. 18%, P = 0.003; 3 months, 66% vs. 29%, P = 0.005). Patients who became stone-free within 1 month showed larger ejection fractions than patients with retained fragments (67% +/- 4% vs. 56% +/- 3% before UDCA, P = 0.032; 65% +/- 4% vs. 53% +/- 3% with UDCA, P = 0.017). Further, ejection rate during UDCA therapy was larger in patients with complete gallstone disappearance within 1 month than in patients with delayed fragment clearance (1.57%/min +/- 0.36%/min vs. 0.76%/min +/- 0.09%/min; P = 0.002).

CONCLUSIONS

Gallbladder emptying is a major determinant of early gallstone clearance after lithotripsy.

Three-dimensional ultrasonography in hepatobiliary and pancreatic diseases

Three-dimensional reconstruction of ultrasonographic images was used to visualize hepatobiliary and pancreatic lesions and stones, and to measure gallbladder emptying. The initial experience shows that these reconstructions may be of some help in the identification of the extension of tumors and the invasion into surrounding tissues. Stones and stone fragments in the pancreas and in the gallbladder as well as the wall of the gallbladder were visualized well. If further studies will reveal a benefit for the patient, three-dimensional ultrasonography may be added to the noninvasive methods used in the diagnosis of several hepatobiliary and pancreatic diseases.

Pathogenic factors in early recurrence of cholesterol gallstones

BACKGROUND/AIMS

Supersaturation of bile with cholesterol, rapid nucleation of cholesterol crystals, and/or incomplete emptying of the gallbladder are believed to be required for gallstone formation. The importance of these factors for the recurrence of gallbladder stones was studied.

METHODS

Twenty patients, untreated after successful shock wave therapy, were studied in a matched case-control design for bile acid turnover, composition of duodenal bile, and gallbladder emptying. In 10 of them, gallstones had recurred within 12 +/- 2 months (X +/- SEM); the other 10 had been free of stones since 22 +/- 3 months.

RESULTS

In each group, duodenal bile was supersaturated with cholesterol in 8 of 10 patients and showed abnormal nucleation time of cholesterol crystals in half of the patients. Patients with recurrent stones had smaller pool sizes of cholic acid (-43%) and enhanced conversion of cholic acid to deoxycholic acid. The odds for stone recurrence were ninefold increased in the presence of excessive deoxycholic acid (exceeding cholic acid) in the bile acid pool or incomplete emptying of the gallbladder (residual volume > 5 mL) in response to cholecystokinin. The odds ratio was over 20-fold increased when incomplete emptying of the gallbladder coincided with supersaturated bile or with excessive deoxycholic acid.

CONCLUSIONS

Enhanced conversion of cholic acid to deoxycholic acid and incomplete emptying of the gallbladder could be important cofactors for the recurrence of gallstones.

Combination of extracorporeal shock-wave lithotripsy and dissolution of gallbladder stones with methyl tert-butyl ether: a randomized study

We conducted a prospective randomized study in gallstone patients to determine whether a combination of extracorporeal shock-wave lithotripsy and subsequent dissolution with methyl tert-butyl ether increases the success rate of methyl tert-butyl ether dissolution and shortens treatment time compared with monotherapy with methyl tert-butyl ether. Fifty patients were randomized into two groups. Twenty-five patients underwent extracorporeal shock-wave lithotripsy before contact dissolution with methyl tert-butyl ether, and 25 patients were treated with methyl tert-butyl ether alone. All patients had at least three stones or stones larger than 30 mm that were radiolucent on x-ray and had densities of less than 140 Hounsfield Units (HU) on computed tomography. Overall, the combined approach neither shortened the treatment time significantly vs. monotherapy with methyl tert-butyl ether nor reduced the time of hospitalization. The success rate was slightly but not significantly increased compared with that of methyl tert-butyl ether therapy alone. The recurrence rate was similar in the two groups after a median follow-up of 1 yr. However, when subgroups of patients with at least one stone larger than 15 mm or with stones with densities of more than 60 HU were analyzed, the clearance rate after 5 mo was significantly higher (p < 0.005 and p < 0.025, respectively) in patients subjected to a combination of extracorporeal shock-wave lithotripsy and methyl tert-butyl ether dissolution. Extracorporeal shock-wave lithotripsy and methyl tert-butyl ether did not expose patients to more adverse effects than did treatment with methyl tert-butyl ether alone.

Gallstone recurrence after shock-wave therapy

BACKGROUND/AIMS

The long-term outcome of nonoperative gallstone therapy depends on both absence of stones and absence of biliary pain. The aim of the present study was to determine the rate of stone recurrence and the rate of symptoms within 5 years after successful shock wave lithotripsy combined with bile acid therapy.

METHODS

One hundred consecutive patients (single stones, n = 89; 2 or 3 stones, n = 11) were followed up for a median of 4.3 years after stone disappearance and discontinuation of bile acids.

RESULTS

Twenty-three of the 100 patients developed recurrent stones. Calculated by actuarial analysis, the recurrence rate was 7% +/- 3%, 11% +/- 3%, 13% +/- 4%, 20% +/- 5%, and 31% +/- 7% (mean +/- SD) at 1, 2, 3, 4, and 5 years, respectively. The recurrent stones were small (6 +/- 5 mm) and were associated with recurrent biliary pain in 14 (61%) of the 23 patients. Repeated shock wave lithotripsy and/or bile acid medication resulted in stone disappearance in only 10 of 20 patients with recurrence.

CONCLUSIONS

The long-term rate of stone recurrence after lithotripsy of primarily solitary gallbladder calculi is lower than expected from post-bile acid dissolution trials. Recurrence of stones frequently is associated with recurrence of biliary pain.

Correlation between gall bladder fasting volume and postprandial emptying in patients with gall stones and healthy controls

To evaluate whether the extent of postprandial gall bladder emptying is correlated with gall bladder fasting volume, gall bladder motility was studied in 56 patients with cholesterol gall stone and 19 control patients. Gall bladder volumes were determined sonographically, while cholecystokinin plasma values were measured radioimmunologically. Twenty three per cent of gall stone patients were classified as pathological contractors (residual fraction > mean +2SD of controls) and 77% as normal contractors. Normal but not pathological contractor patients exhibited larger gall bladder fasting volumes (mean (SEM)) (24.7 (1.7) ml) than controls (15.3 (1.2) ml, p < 0.001). In normal contractor patients and controls fasting volume was closely related with ejection volume (r = 0.97, p < 0.001) and residual volume (r = 0.80, p < 0.001). Although ejection volume was enlarged in normal contractor patients it did not compensate the increase in fasting volume. Thus, residual volumes were considerably increased not only in pathological contractors (12.7 (2.5) ml, p < 0.001) but also in normal contractor patients (7.0 (0.5) v 4.6 (0.6) ml, p < 0.001). Postprandial cholecystokinin secretion did not differ between patients and controls. It is concluded, that in normal contractor patients gall bladder fasting volume is closely correlated with ejection and residual volume. Thus, fasting volume may be an essential factor affecting postprandial gall bladder emptying. Large fasting volumes in cholesterol gall stone disease could thereby contribute to bile retention, which facilitates gall stone growth.

[Shockwave therapy of gallstones]

Extracorporeal shock-wave lithotripsy (ESWL) is a helpful adjunct for those bile duct stones which cannot be extracted by routine endoscopic measures including mechanical lithotripsy. For very large or impacted stones in the bile duct or stones in the intrahepatic biliary tree, and also for stones located in proximity to a bile duct stenosis, shock-wave therapy has proven to be safe and successful. More than 85% of the patients become free of stones after this therapy; they otherwise would have had to undergo high-risk open bile duct surgery. For gallbladder calculi, the pivotal factor for complete fragment disappearance after shock-wave therapy is sufficient stone disintegration. Only if fragments not larger than 3 mm are achieved, complete expulsion and/or dissolution of these fragments may be expected in a high percentage of the patients. Optimal candidates include patients with a single, radiolucent stone in a well-contracting gallbladder. For this group, ESWL is a safe and effective noninvasive therapeutic alternative.

[Transjugular liver puncture]

The transjugular liver biopsy is a method which allows assessment of hepatic tissue from patients with contraindications against classical percutaneous biopsy. A catheter with a long biopsy needle within is inserted into the jugular vein and then pushed forward through the Vena cava into a hepatic vein in order to carry out the biopsy of the liver. Indications for this examination are biopsies in patients with considerably impaired coagulation or tense ascites. It is possible, if necessary, to measure free and wedged pressure within the liver veins during this examination. On average, in 93% of all examinations enough tissue is yielded to allow for satisfactory judgement of histological changes; the rate of success is little less than that with percutaneous biopsies. However, considering all aspects, this technique gives good results. Lethal complications are rare (0.17%); the total complication rate is about 12%, 0.5-2.7% are severe. Although this method needs more time and technical equipment than percutaneous biopsy, the procedure has to be considered as an important technique for the evaluation of terminal liver disease.

[Recent aspects in diagnosis and therapy of esophageal varices]

Esophageal varices are of ominous significance in patients with cirrhosis. Diagnostic procedures are undertaken for evaluation of the bleeding risk. Whereas after a recent bleeding event the risk of rebleeding is high (up to 70%) and rebleeding prophylaxis is obligatory, the risk of first bleeding in patients who never bled depends on the presence of bleeding risk indicators. Endoscopy is the most powerful tool for assessment of the bleeding risk. Variceal size, the presence of the red color sign and the presence of concomitant fundic varices indicate a high risk of first bleeding. Currently used endoscopic or medical prophylaxis has a high rate of failure. On the other hand, operative measures prevent bleeding in most patients. However, the perioperative morbidity and mortality is high. Controlled studies will show whether the patients will benefit from new experimental treatment approaches (endoscopic obliteration of varices, endoscopic ligation of varices, TIPS and liver transplantation.

Extended cardiopulmonary preservation: University of Wisconsin solution versus Bretschneider's cardioplegic solution

Application of the University of Wisconsin cold storage solution has rapidly expanded to include medium-term to long-term preservation of virtually all intraabdominal organs. Its use in intrathoracic organ transplantation has also been suggested. We therefore examined the efficacy of the University of Wisconsin solution in a primate allotransplantation model for preservation of hearts, and as a simple single-solution system for static preservation of heart-lung blocks, for periods of ischemia ranging from 6 to 24 hours. For comparison, we employed the histidine-tryptophane-ketoglutarate cardioplegic solution of Bretschneider. University of Wisconsin solution provided superior results with regard to clinical outcome and hemodynamic recovery of hearts after ischemic periods of up to 16 hours. This was in contrast to Bretschneider's solution, which allowed storage of hearts for periods of only up to 10 hours. Heart-lung blocks were equally well preserved with either University of Wisconsin or Bretschneider's solution after 6 to 12 hours, although the University of Wisconsin solution group exhibited a more notable increase in pulmonary water content. This was in accordance with histological data, which suggested that, although hemodynamic recovery of hearts stored for periods longer than 10 hours was poor, preservation of pulmonary ultrastructure was far superior using Bretschneider's solution as compared with University of Wisconsin solution after an ischemic period of up to 16 hours.

Gallbladder emptying is an important factor in fragment disappearance after shock wave lithotripsy

The role of gallbladder emptying in fragment disappearance following shock wave lithotripsy of gallstones is poorly understood. We studied gallbladder motility in two groups of patients who had been treated by electrohydraulic shock wave lithotripsy and bile acid dissolution therapy. Group I (n = 20) consisted of patients with fragment disappearance within 18 months after lithotripsy, while patients in group II (n = 20) still harboured fragments in the gallbladder 18 months after lithotripsy. Fasting gallbladder volume was 19 +/- 10 ml (mean +/- S.D.) in group I, and 24 +/- 12 ml in group II (not significant). The residual volume was 8 +/- 9 ml in group I, but 18 +/- 14 ml in group II (p < 0.005). Thus, patients in group I ejected nearly twice as much of the fasting gallbladder volume as patients in group II. This difference in gallbladder emptying was still present if only the patients with single stones were compared in both groups. From the results of this retrospective study we conclude that gallbladder emptying is an important factor for complete fragment disappearance after gallstone disintegration by extracorporeally generated shock waves. Further prospective studies are needed to confirm these observations.