Sonographic evaluation of gallbladder volume and ejection fraction in obese women without gallstones

PURPOSE: Obese people have an increased incidence of gallstones. Although the exact pathogenic mechanisms of gallstone development are unknown, impaired gallbladder emptying has been suggested as a possible underlying mechanism. Our aim was to investigate this possibility by evaluating gallbladder motility and related factors in obese and nonobese women without gallstones. METHODS: This study included 79 obese women and 25 nonobese healthy women. Using real-time sonography, we evaluated fasting and postprandial (15th-, 30th-, 45th-, 60th-, 75th-, 90th-, 120th-, and 150th-minute) gallbladder volumes and ejection fractions. The smallest postprandial volume was considered the residual volume. RESULTS: Mean (+/- standard deviation) fasting and residual gallbladder volumes were 43.2 +/- 18.3 cm(3) and 21.4 +/- 11.2 cm(3), respectively, in the obese women and 28.1 +/- 12.3 cm(3) and 7.9 +/- 3.4 cm(3), respectively, in the nonobese women. Maximal ejection fraction was 49 +/- 19% in obese women and 63 +/- 29% in nonobese women (p = 0.001). The fasting and residual volumes and the postprandial volumes at all time points were higher in obese women than in nonobese women (p < 0.001). In addition, 15th-, 30th-, 45th-, 60th-, 75th-, and 90th-minute postprandial ejection fractions were lower in obese women than in nonobese women (p < 0.001). Positive correlations were found between fasting gallbladder volume and body mass index and body fat weight and between residual volume and body mass index, waist circumference, body fat percentage, and body fat weight (p < 0.05 for all comparisons). CONCLUSIONS: Our results show that fasting and postprandial gallbladder volumes are higher and that postprandial gallbladder motility is lower in obese than in nonobese women. There are positive correlations between fasting gallbladder volume and body weight, body mass index, and body fat weight.     

Gallbladder contractility in patients with cirrhotic versus malignant ascites

PURPOSE: The aim of this study was to evaluate differences in gallbladder contractility by measuring gallbladder wall thickness, fasting and residual gallbladder volume, and gallbladder ejection fraction in patients with cirrhotic and malignant ascites. METHODS: Twenty-four patients (16 women and 8 men) with malignant ascites (2 cervical, 2 colon, 2 stomach, 6 pancreatic, and 12 ovarian carcinomas), aged 59 +/- 12 years, and 26 patients (14 women and 12 men) with cirrhotic ascites, aged 57 +/- 16 years, were included in the study. After patients fasted overnight for 8 hours, gallbladder wall thickness, fasting gallbladder volume, and gallbladder volume and ejection fraction were measured sonographically at 10, 20, 30, 40, 50, 60, 70, 80, and 90 minutes after ingestion of a standard liquid test meal. RESULTS: The mean gallbladder wall thickness was higher in patients with cirrhotic ascites than in those with malignant ascites (5.5 +/- 1.5 mm [standard deviation] versus 3.1 +/- 0.6 mm, respectively; p < 0.001). The mean fasting gallbladder volume was also higher in patients with cirrhotic ascites than in those with malignant ascites (27.3 +/- 11.5 cm(3) versus 17.6 +/- 8.9 cm(3); p < 0.05). Patients with cirrhotic ascites had significantly higher mean postprandial gallbladder volumes and ejection fractions than did those with malignant ascites at all times except 10 minutes after the meal (p < 0.05). CONCLUSIONS: Our findings suggest that gallbladder contractility is greater in patients with cirrhotic ascites than in patients with malignant ascites.     

Effect of rectal distension on gallbladder emptying and circulating gut hormones

BACKGROUND: Abnormalities of upper gut motility, including a delay of gastric emptying and small bowel transit, found in patients with constipation may be secondary to factors originating in the colon or rectum as a result of faecal stasis. The aim was to determine if stimulation of mechanosensory function by rectal distension affects postprandial gallbladder emptying and release of gastrointestinal peptides participating in control of upper gut motility. MATERIALS AND METHODS: Eight healthy volunteers were studied with an electronic barostat and a plastic bag positioned in the rectum. Intrabag pressure was maintained at minimal distension pressure + 2 mmHg on one occasion and on a pressure that induced a sensation of urge on the other. Gallbladder volume and plasma concentrations of cholecystokinin (CCK), pancreatic polypeptide (PP) and peptide YY (PYY) were measured before and after ingestion of a 450-kcal mixed liquid meal. RESULTS: Rectal distension enhanced maximum gallbladder emptying from 66 +/- 7% to 78 +/- 5% (P < 0.05). Distension tended to increase integrated plasma PYY from 77 +/- 30 pM min to 128 +/- 40 pM min in the first hour after the meal (P = 0.08) and it suppressed integrated plasma PP from 1133 +/- 248 pM min to 269 +/- 284 pM min in the second hour (P < 0.05). Integrated plasma CCK concentrations were not significantly affected. CONCLUSION: Mechanosensory stimulation of the rectum enhances postprandial gallbladder emptying and influences postprandial release of gut hormones involved in the regulation of gastrointestinal motility in healthy subjects. These mechanisms may play a role in the pathogenesis of the upper gastrointestinal motor abnormalities observed in constipated patients.     

Effects of cholestyramine on gallbladder and gastric emptying in obese and lean subjects

Abstract. Gallbladder stasis is frequent in obese subjects and may contribute to their increased risk for gallstone formation. The bile salt sequestrant cholestyramine acutely enhances postprandial gallbladder emptying in lean subjects, through dis-inhibition of a negative feedback between intraluminal bile salts and CCK release. In this study the effect of cholestyramine on both gallbladder and gastric antrum dynamics were studied by realtime ultrasonography in 12 obese and 15 lean subjects. For the acute study, on different days, subjects ingested a liquid meal (two egg yolks plus water 200 mL, 50 kJ) or a meal with 4g cholestyramine. Gallbladder emptying was impaired in obese patients who had significantly larger fasting gallbladder volume (39.4 ± 6.9 vs. 21.6 ± l.7mL, P <0.02), larger residual volume (12.3 ± 1.8 vs. 4.0 ± 0.5ml, P < 0.0006) and slower emptying time ( T /2: 33 ± 2 vs. 21 ± 2 min, P < 0.05) than lean subjects. Integrated antral emptying was also less in obese than lean subjects (5521 ± 578 vs. 7908 ± 491 % 120min^-1, P <0.02). Cholestyramine enhanced postprandial gallbladder emptying in both obese and lean subjects. Gastric emptying was delayed with cholestyramine in lean but not obese subjects. For the chronic study, after 1 month therapy with cholestyramine (4 g every 2 days), the motility tests were repeated in nine obese subjects. Gallbladder and gastric responses to a test meal, with or without cholestyramine, were preserved. We conclude that both gallbladder and antral emptying of a liquid test meal are impaired in obese subjects. Gallbladder emptying improves after acute administration of a low dose cholestyramine with test meal. This effect is sustained after 1 month treatment with a low dose of cholestyramine and does not interfere with gastric emptying of obese patients. Cholestyramine may improve gallbladder hypomotility in obese people.     

Left ventricular performance during prolonged exercise: absence of systolic dysfunction

We assessed left ventricular systolic and diastolic performance during and after prolonged exercise under controlled conditions in a group of healthy, trained men. Previous studies have examined the effects of prolonged effort on left ventricular function, yet it remains unclear whether or not left ventricular dysfunction (e.g. cardiac fatigue) can be produced under such conditions. We studied 15 healthy men, aged 27+/-1 years (mean+/-S.E.M.). Subjects exercised on bicycles at a constant work rate (60% of maximum oxygen uptake per min) for 150 min. Measurements of gas exchange, blood pressure and haematocrit were obtained, concurrent with the assessment of left ventricular function using equilibrium radionuclide angiography, at rest, during exercise (every 30 min) and after 30 min of recovery. Fluid replacement was provided and monitored during the exercise period. The baseline resting and exercise ejection fractions were 66+/-2% and 78+/-2% respectively. During exercise, subjects consumed 1816+/-136 ml of fluid, and the haematocrit had increased at 120 min of exercise (from 47.2%+/-0.6 to 49.9+/-0.8%; P<0.05). There was no change in either systolic or diastolic blood pressure throughout the exercise period, but heart rate drifted upwards from 141+/-2 beats/min after 30 min to 154+/-3 beats/min after 150 min (P<0.05). There was a small decline (8%; P<0.05) in end-diastolic volume at 150 min. No changes were observed in left ventricular ejection fraction, the pressure/volume ratio or end-systolic volume. After 30 min of sitting in recovery, heart rate was still higher than the pre-exercise value (84+/-3 compared with 69+/-2 beats/min; P<0.05), as were measures of peak filling rate and time to peak filling (P<0.05). The ejection fraction in the post-exercise recovery period was similar to the pre-exercise value. The results indicate that prolonged exercise of moderate duration may not induce abnormal left ventricular systolic function or cardiac fatigue during exercise.     

Effect of sildenafil citrate on postprandial gallbladder motility

OBJECTIVE: Sildenafil stimulates the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway through inhibition of type 5 phosphodiesterase. NO-cGMP pathway causes smooth muscle relaxation. The aim of this study is to evaluate the effects of sildenafil on gallbladder motility. METHODS: Twenty healthy male volunteers (21-35 years old) participated in this randomized, double blind, crossover, and placebo-controlled study. Oral sildenafil (50 mg) or placebo was randomly dispensed to each volunteer on two consecutive days. After the sildenafil or placebo, a special meal with a high fat content was administered. Gallbladder volume was measured using sonography preprandially and at 5, 15, 30, 60, 120 and 180 minutes postprandially. RESULTS: Sildenafil showed an inhibitory effect on gallbladder contraction in healthy volunteers that began at 30 minutes. Gallbladder volumes showed significant differences at 30 minutes following the test meal (approximately 50-60 min after the sildenafil intake), between placebo (15.4 +/- 5.1 mL) and the sildenafil groups (19.3 +/- 6.1 mL) (P < 0.05). In addition, gallbladder volume was significantly higher during the refilling phase in the sildenafil group (P < 0.05 at 180 min). Maximal contraction was achieved at 60 minutes in each group. CONCLUSIONS: Sildenafil constituted a significant inhibitory effect on gallbladder discharge in healthy individuals when compared with placebo group. Because of this inhibitory effect, sildenafil consumption for long periods may potentiate risks of gallbladder disorders and gallstone formation resulting from disturbed gallbladder motility.     

Changes of gallbladder and gastric dynamics in patients with acute hepatitis A

Transient alterations of gallbladder morphology and dynamics have been reported in patients with during acute hepatitis A. The presence of dyspepsia also suggests involvement of gastric motility. During a 60-day follow-up, we investigated gallbladder and gastric motility in relation to dyspepsia in acute viral hepatitis A patients. Twenty patients were assessed at referral (day 0) and at days 7, 21, 42 and 60 and compared with 20 healthy volunteers. Gallbladder morphology and motility and gastric motility were assessed in the fasting and postprandial period by functional ultrasonography using a liquid test meal. Dyspeptic symptoms were scored. At day 0, fasting gallbladder volume was 5.9 +/- 1.3 mL, 32.6 +/- 4.6 mL, and 21.5 +/- 1.9 mL (mean +/- SE) in patients with gallbladder sludge (n = 7), without sludge (n = 13) and controls, respectively (P < 0.05 in sludge vs. no sludge and controls; P < 0.05 in no sludge vs. controls, ANOVA). Small fasting gallbladder volume in patients with sludge increased and sludge disappeared within 7 days. At day 0, patients with sludge also had increased thickness of fasting gallbladder wall and increased serum transaminase levels compared with patients without sludge and controls. Gallbladder contraction was similar in patients and controls. However, patients had delayed gastric emptying, which positively correlated with dyspepsia score. Gallbladder morphological changes observed in the acute phase of hepatitis A are transient and are associated with hepatocellular damage. Gastric emptying is delayed during the first week of disease and is associated with dyspeptic symptoms.     

Effect of somatostatin on postprandial gallbladder relaxation

Although the inhibitory effect of somatostatin (SST) on gallbladder contraction is well known, the influence of SST on gallbladder motility during the late postprandial or relaxation phase has not been studied. We therefore investigated the effect of SST on gallbladder relaxation and gut hormone release during the late postprandial phase. Eight healthy volunteers participated in two experiments performed in random order during continuous infusion of either SST or saline (placebo) starting 2 h after meal ingestion. At regular intervals, gallbladder volumes were measured (ultrasonography) and blood samples were taken for determination of plasma cholecystokinin (CCK), pancreatic polypeptide (PP), peptide YY (PYY) and neurotensin levels (radioimmunoassay). Postprandial gallbladder contraction was similar in both experiments: 68 ± 4% vs. 66 ± 4%. During SST infusion, postprandial gallbladder contraction was significantly (P<0·01) reduced (2874 ± 813% *240 min) compared with saline (9391 ± 1595% *240 min). Plasma CCK, PP, PYY and neurotensin levels were in the same range in the early postprandial phase but were significantly reduced during SST infusion compared with placebo (late postprandial phase). Plasma levels of CCK correlated with gallbladder volumes during both the contraction and relaxation phase (r=0·68, P=0·01 and r=0·61, P=0·008, respectively). SST enhances gallbladder relaxation and reduces hormone secretion in the late postprandial phase. The results point to an association between CCK and gallbladder volume not only during the postprandial contraction phase but also during the relaxation phase.     

Three-dimensional sonographic evaluation of gallbladder contractility: comparison with cholescintigraphy

PURPOSE: To compare three-dimensional sonography (3D US) with quantitative cholescintigraphy for assessing gallbladder contractility. METHODS: Gallbladder radioactivity was assessed in 35 patients with suspected gallbladder disease using a gamma camera 5, 30, 60, and 90 minutes after technetium 99m (Tc-99m) DISIDA injection and 30 and 60 minutes after ingestion of a high-fat meal. Immediate gallbladder images were obtained via 3D US. Gallbladder radioactivity at 120 minutes after injection of Tc-99m DISIDA was defined as 100%, and gallbladder contractility was calculated. Gallbladder volume on 3D US was calculated using a dedicated software. Pearson correlation analysis and simple linear regression analysis were used. RESULTS: The mean gallbladder volume on 3D US was 25.3 ml after fasting and 6.6 ml after a high-fat meal. The mean gallbladder contractility index was 77.7% on cholescintigraphy (range, 18-99) and 73.4 on 3D US (range, 16.7-97.3). A linear correlation between cholescintigraphy and 3D US contractility indices was observed. The r value on Pearson analysis was 0.92 and R(2) of the coefficient of determination was 0.85. The difference in measured contractility between the 2 methods ranged from +21.5% to -15.0% (mean +/- SD, 4.4 +/- 8.7%). CONCLUSIONS: 3D US is a reliable and easy method for clinical measurement of the volume of the gallbladder and its contractility.     

Effect of verapamil in elderly patients with left ventricular diastolic dysfunction as a cause of congestive heart failure

Fifteen elderly patients with normal left ventricular (LV) systolic function and New York Heart Association functional class II-III were studied. The effect of verapamil on LV diastolic function was assessed by congestive heart failure (CHF) score, treadmill exercise test, and Doppler echocardiography at baseline, and after each three-month treatment period (placebo or verapamil 120 mg once daily), separated by a one-week washout period before crossover. Blood pressure, heart rate, LV ejection fraction, LV mass, and cardiac output were unaltered by placebo or verapamil. Verapamil treatment significantly improved CHF score at 3 months (3.5 +/- 0.5, p<0.05) compared with baseline (5.6 +/- 0.5) or placebo (5.5 +/- 0.5). The exercise time was similar at baseline (7.4 +/- 1.2 min) and after placebo (7.4 +/- 1.3 min) treatment but significantly (p<0.05) increased after verapamil (8.3 +/- 1.2 min) treatment. The ratio of mitral A wave duration/pulmonary venous atrial systolic reversal duration increased after verapamil (1.11 +/- 0.08) treatment compared with placebo (0.91 +/- 0.07, p<0.05) and baseline (0.89 +/- 0.08) which had similar durations. The isovolumic relaxation time was significantly (p<0.05) decreased from 84 +/- 12 ms at baseline and 86 +/- 13 ms with placebo to 73 +/- 9 ms with verapamil. The results of this study suggest that in elderly patients with Doppler evidence of diastolic dysfunction as the cause of CHF, three months treatment with verapamil can improve CHF, increase exercise tolerance and improve LV diastolic function.     

Moderate exercise, postprandial lipaemia and triacylglycerol clearance

Moderate intensity exercise reduces postprandial triacylglycerol (TG) concentrations. We tested whether this reflects increased TG clearance. Eight normotriglyceridaemic men, aged 48.3 +/- 7.3 years (mean +/- SD), performed two oral fat tolerance tests (blood samples taken in the fasted state and for six hours after a high-fat meal containing 1.00 g fat, 0.97 g carbohydrate, 58 kJ energy kg-1 fat-free body mass) and two intravenous fat tolerance tests (blood samples in the fasted state and after a bolus injection of Intralipid, 0.1 g fat kg-1 body mass). The afternoon before one oral and one intravenous test, subjects walked briskly for 90 min; no exercise was performed before the control tests. Prior exercise reduced fasting TG concentration similarly in the oral (16 +/- 7 %) (mean +/- SEM) and intravenous (18 +/- 7 %) tests, and reduced postprandial TG concentrations in the oral test by 18 +/- 6 % (all P < 0.05). However, prior exercise did not increase Intralipid clearance (disappearance curve slopes: control, 4.69 +/- 0.49 % min-1; exercise, 4.85 +/- 0.40 % min-1). These data suggest that mechanisms other than increased TG clearance mediate the lower postprandial TG concentrations seen after moderate exercise.     

Gallbladder and gastric motility in patients with idiopathic slow-transit constipation

OBJECTIVE: Idiopathic slow-transit constipation (STC) has been suggested to be a pangastrointestinal motility disorder. We investigated scintigraphically whether motility in the gallbladder and stomach was impaired in slow-transit constipation. METHODS: Twenty-four patients with STC were studied. Colon transit time, gallbladder motility, and solid-phase gastric emptying were measured by scintigraphy. RESULTS: Gallbladder dysmotility was observed in 8 of 18 (44.4%) patients. Mean gallbladder ejection fraction was 41.6 +/- 13.6% (range, 16.3-67.0%). Gastric emptying was delayed in 9 of 18 (50%) patients. Mean solid-phase gastric half-emptying time was 75 minutes. STC may be associated with impaired function of other gastrointestinal organs. Approximately half of patients with STC presented gallbladder or gastric dysmotility. CONCLUSION: STC may not be a pure colonic abnormality; it may be a component of a pangastrointestinal tract motility disorder involving several organs.     

Thermic effect of food at rest, during exercise, and after exercise in lean and obese men of similar body weight.

The thermic effect of food at rest, during 30 min of cycle ergometer exercise, and after exercise was studied in eight lean (mean +/- SEM, 10 +/- 1% body fat, hydrostatically-determined) and eight obese men (30 +/- 2% body fat). The lean and obese mean were matched with respect to age, height, weight, and body mass index (BMI) to determine the relationship between thermogenesis and body composition, independent of body weight. All men were overweight, defined as a BMI between 26-34, but the obese had three times more body fat and significantly less lean body mass than the lean men. Metabolic rate was measured by indirect calorimetry under four conditions on separate mornings, in randomized order, after an overnight fast: 3 h of rest in the postabsorptive state; 3 h of rest after a 750-kcal mixed meal (14% protein, 31.5% fat, and 54.5% carbohydrate); during 30 min of cycling and for 3 h post exercise in the postabsorptive state; and during 30 min of cycling performed 30 min after the test meal and for 3 h post exercise. The thermic effect of food, which is the difference between postabsorptive and postprandial energy expenditure, was significantly higher for the lean than the obese men under the rest, post exercise, and exercise conditions: the increments in metabolic rate for the lean and obese men, respectively, were 48 +/- 7 vs. 28 +/- 4 kcal over 3 h rest (P less than 0.05); 44 +/- 7 vs. 16 +/- 5 kcal over 3 h post exercise (P less than 0.05); and 19 +/- 3 vs. 6 +/- 3 kcal over 30 min of exercise (P less than 0.05). The thermic effect of food was significantly negatively related to body fat content under the rest (r = -0.55), post exercise (r = -0.66), and exercise (r = -0.58) conditions. The results of this study indicate that for men of similar total body weight and BMI, body composition is a significant determinant of postprandial thermogenesis; the responses of obese are significantly blunted compared with those of lean men.     

Gallbladder motility and cholesterol crystallization in bile from patients with pigment and cholesterol gallstones

BACKGROUND: Little is known about gallbladder motility in patients with black pigment stones when compared to cholesterol gallstone patients, or about their relationship to biliary composition, crystallization and stone characteristics. DESIGN: Fasting and postprandial gallbladder volumes were studied by ultrasonography in 49 gallstone patients with pigment (n = 14) or cholesterol (n = 35) stones and 30 healthy controls. After cholecystectomy stone composition, gallbladder wall inflammation, cholesterol saturation index and appearance of platelike cholesterol crystals in bile were evaluated in gallstone patients. RESULTS: Fasting gallbladder volume was significantly (P < 0.05) increased in cholesterol stone patients (31.7 +/- 1.9 mL) but not in pigment stone patients (21.9 +/- 3.1 mL), compared to controls (21.0 +/- 1.5 mL). Postprandial emptying was delayed in patients (half-emptying time: 31 +/- 2 min, 35 +/- 3 min, 24 +/- 2 min in cholesterol stone patients, pigment stone patients and controls, respectively, P < 0.05) and incomplete (residual volume: 43.2 +/- 2.7%, 40.0 +/- 4.3%, 15.8 +/- 1.6% min in cholesterol stone patients, pigment stone patients and controls, respectively, P < 0.05). The inflammation of the gallbladder wall was mild or absent in all cases. Biliary cholesterol saturation index was 152.3 +/- 8.5% and 92.9 +/- 4.8% in patients with cholesterol and pigment stones, respectively (P < 0.01). Whereas cholesterol crystals never appeared during 21 days in biles from patients with pigment stones, crystal observation time in patients with cholesterol gallstone was 5 days (median) and was significantly shorter in patients with multiple (4 days) than in patients with solitary (12 days) cholesterol stones (P = 0.0019). CONCLUSIONS: Patients with black pigment stones who do not have excess cholesterol and do not grow cholesterol crystals in bile have decreased gallbladder emptying, although to a lesser extent than patients with cholesterol stones. Thus, gallbladder stasis is likely to put a subset of subjects at risk for the formation of pigment gallstones, and pathogenic mechanisms need to be further investigated.     

Are the reductions in triacylglycerol and insulin levels after exercise related?

Moderate exercise improves insulin sensitivity and reduces triacylglycerol (triglyceride; TG) concentrations. We hypothesized that changes in insulin sensitivity are an important determinant of exercise-induced changes in postprandial TG concentrations. Altogether, 38 men and 43 women, all of whom were normotriglyceridaemic and normoglycaemic, each underwent two oral fat tolerance tests with different pre-conditions: control (no exercise) and prior exercise (90 min of exercise at 60% of maximal O(2) uptake the day before). Venous blood samples were obtained in the fasting state and for 6 h after a high-fat mixed meal. In the control trial there were significant correlations between log fasting TG concentration and log fasting insulin concentration (r=0.42, P<0.0005) and between log postprandial TG response (area under the curve) and log postprandial insulin response (r=0.48, P<0.0005). Prior exercise reduced the fasting TG concentration by 18.2 +/- 2.2% (mean +/- S.E.M.) (P<0.0005), the postprandial TG response by 21.5 +/-1.9% (P<0.0005), the fasting insulin concentration by 3.8 +/- 3.1% (P<0.01) and the postprandial insulin response by 11.9 +/- 2.5% (P<0.0005). However, there was no relationship between the exercise-induced changes in log fasting TG and log fasting insulin (r=0.08, P=0.50), nor between the exercise-induced changes in log postprandial TG response and log postprandial insulin response (r=0.04, P=0.70). These data suggest that the reductions in fasting and postprandial TG levels elicited by a session of moderate-intensity exercise are not mediated by an increase in insulin sensitivity.     

Comparison of Sonography and Scintigraphy in the Evaluation of Gallbladder Functional Studies With Cholecystokinin

Objective. Both sonography and scintigraphy have been used to evaluate gallbladder function with the use of sincalide (cholecystokinin [CCK]). However, the reported ejection fractions (EFs) for the two modalities are not the same. The techniques measure slightly different parameters. This study directly compared both techniques performed simultaneously on the same participants. Methods. Twenty healthy volunteers were evaluated with sonography and scintigraphy to estimate the gallbladder EF simultaneously. The gallbladder EF was calculated at 5‐minute intervals for 1 hour. Results. The mean EFs ± SD were 66.3% ± 20% and 49% ± 29% for sonography and scintigraphy, respectively. The mean times to the peak EF were 38 ± 12 and 33 ± 9 minutes for sonography and scintigraphy. An average time of 34 minutes was noted after radiopharmaceutical injection before CCK administration for the scintigraphic studies. The earliest time to the peak EF for sonography was 15 minutes, and the latest time to the peak EF was 60 minutes (mode, 40 minutes); for scintigraphy, the earliest and latest times were 15 and 50 minutes (mode, 30 minutes), respectively. One participant could not be evaluated secondary to nonfilling of the gallbladder on scintigraphy. There was wider variability of the gall‐bladder EF with scintigraphy than sonography. Conclusions. Scintigraphy estimated a lower EF than sonography, had wider EF variability than sonography, and required additional time (>30 minutes more) to complete the study. Scintigraphy could not be performed in 5% of the participants because of nonfilling of the gallbladder. The use of sonography to estimate the gallbladder EF is less time‐consuming and less costly. With these techniques, the range of normal gallbladder EFs should be adjusted for the technique used.     

Effects of a novel cholecystokinin (CCK) receptor antagonist, MK-329, on gallbladder contraction and gastric emptying in humans. Implications for the physiology of CCK.

To explore the physiology of cholecystokinin (CCK) in humans, we investigated the effect on gallbladder contraction and gastric emptying of a recently developed CCK receptor antagonist, MK-329. In a double-blind, four-period crossover study eight subjects received single doses of 0.5, 2, or 10 mg MK-329, or placebo, followed by an intravenous infusion of CCK-8 (30 pmol/kg.h). In placebo-treated subjects gallbladder volumes decreased on average to 43% of initial volumes after 2 h of CCK infusion. MK-329 caused a dose-dependent inhibition of CCK-stimulated gallbladder contraction with 10 mg producing complete blockade (P less than 0.01, cf. placebo). Gallbladder contraction and gastric emptying rates after a mixed meal were then measured in a two-period crossover study. Subjects received placebo or 10 mg of MK-329 2 h before eating. Gastric emptying of both solids and liquids was measured simultaneously by gamma scintigraphy. In placebo-treated subjects plasma CCK levels increased postprandially to 2.3 pM, gallbladder volumes decreased 68.4 +/- 3.8% (SE), and the times for 50% emptying of liquids and solids from the stomach were 58 +/- 10 and 128 +/- 8 min, respectively. In MK-329-treated subjects there was a marked elevation in peak CCK levels to 13.8 pM (P less than 0.01, cf. placebo), and gallbladder contraction was completely inhibited. Solid and liquid emptying rates were unaffected. These findings demonstrate that (a) MK-329 is a potent, orally active antagonist of CCK in humans, and (b) CCK is the major regulator of postprandial gallbladder contraction. These data also support the concept of negative feedback regulation of CCK secretion and suggest that mechanisms other than CCK play a dominant role in the regulation of postprandial gastric emptying rates.     

Functional analysis of gallbladder using three-dimensional ultrasound: preliminary results

In evaluating gallbladder function, the clinical feasibility of three-dimensional (3-D) ultrasound (US) using volumetric acquisition was assessed in 30 patients: 18 patients with gallstones and 12 healthy volunteers. 3-D ultrasonography was performed in each patient before and after a fat-meal test. The ejection fraction of the gallbladder from two volumes measured by computer-aided analysis was calculated. There were significant differences in the gallbladder ejection fractions among the diseased and control groups (p < 0.0001). Compared with the results of oral cholecystograms, the ejection fraction of the gallbladder using 3-D volumetry and the grade of oral cholecystography showed good correlation in predicting the gallbladder dysfunction (gamma = 0.71, p = 0.002). Even in cases failing oral cholecystography, the gallbladder ejection fraction using 3-D US was calculated without any difficulty. Conclusively, volumetric acquisition of 3-D US enables us to evaluate gallbladder function and provides a reliable diagnostic yield superior to oral cholecystography.     

Gallbladder emptying in diabetic patients and control subjects assessed by real-time ultrasonography and cholescintigraphy: a methodological comparison

Gallbladder motor function was studied in nine diabetic patients and nine control subjects matched for sex, age, and weight. None of the subjects had gallstones. Two different techniques were employed: real-time ultrasonography and cholescintigraphy using 99mTc-HIDA as imaging agent. Gallbladder volumes were determined sonographically by using three dimensions: length, lateral, and anterior-posterior diameters. Gallbladder emptying was stimulated by a standard test drink (Biloptin). Ejection fraction was computed and the results obtained by both techniques were compared. Fasting and residual gallbladder volumes after contraction were significantly larger in the diabetic patients than in the control subjects (15.9 +/- 7.6 cm3 vs. 2.3 +/- 1.3 cm3, p less than .0007; and 9.2 +/- 9.8 cm3 vs. 0.7 +/- 0.7 cm3, p less than .0007). Ejection fractions (ultrasonography/cholescintigraphy) were lower in the diabetic patients compared with the control subjects (59.9 +/- 26.6% and 63.1 +/- 23.2% vs. 73.2 +/- 23.8% and 75.3 +/- 24.8%), however, this difference was not statistically significant. Sonographically and scintigraphically determined ejection fractions were closely correlated (r = 0.90, p less than .00005).