Sonographic evaluation of resting gallbladder volume and postprandial emptying in patients with gallstones

We investigated fasting gallbladder volume and gallbladder emptying in response to a fatty meal in 20 patients with asymptomatic gallstones and compared the results with findings from healthy controls. Compared with control subjects without gallstones, the majority of patients with gallstones exhibited a higher resting gallbladder volume, less fractional emptying after a fatty meal, and a higher postmeal residual volume. These abnormalities all appeared to stem from an abnormally high resting gallbladder volume. Whether the increased gallbladder volume and decreased postprandial fractional emptying in the gallstone patients represents a primary or secondary abnormality remains to be determined. The results suggest that in some patients decreased gallbladder contractility may contribute to gallstone development or proliferation.     

Gallbladder dynamics induced by a fatty meal in normal subjects and patients with gallstones: concise communication

A study was undertaken to establish the pattern of gallbladder emptying in normal subjects and in patients with gallstones, using a fatty meal as stimulus to release endogenous cholecystokinin. The time from meal ingestion to beginning of gallbladder emptying (latent period), the total duration of emptying (ejection period), degree of emptying (ejection fraction), and the rate of emptying (ejection fraction/ejection period) were measured noninvasively by a nongeometric scintigraphic technique. The mean latent period and ejection rate were similar in normal subjects and patients with gallstones, but the mean ejection period and ejection fraction were significantly reduced in the patients. This study suggests that for an identical stimulus, the gallbladder in cholelithiasis begins to empty at the normal time but empties for a shorter duration; the result is a reduction of ejection fraction but not of ejection rate.     

Gallbladder filling and post-ceruletide emptying in prairie dogs and rabbits

The filling and emptying characteristics of the gallbladder in prairie dogs and rabbits were studied to assess the importance of the residual bile in the pathogenesis of gallstones. In prairie dogs under ketamine/xylazine anesthesia, a significantly larger fraction (p = 0.001) of hepatic bile entered the gallbladder (87 +/- 8%) than the intestine during fasting and very little bile emptied (0-3% ejection fraction) following ceruletide infusion. In rabbits under similar anesthesia, only a small fraction of hepatic bile entered the gallbladder (4 +/- 2%) during fasting, and the gallbladder emptied almost completely (85% ejection fraction) following ceruletide infusion. The resultant higher residual bile in the prairie dog gallbladder and lower residual bile in the rabbit gallbladder may explain why gallstones form so readily in prairie dogs but not in rabbits when fed a lithogenic diet. These similarities and differences in gallbladder function must be taken into account when considering any animal as a model for gallstone formation.     

The effect of age and sex on gallbladder motor dynamics. An echographic study

Aging and female sex are major risk factors for cholesterol gallstones: in addition to hepatic secretion of lithogenic bile, decreased gallbladder contractility may play a role in such physiological conditions. This study was aimed at evaluating the effect of age and sex on gallbladder kinetics in healthy subjects. Gallbladder volume was measured on the US images of 157 fasting subjects using the sum-of-cylinders method. No significant difference was observed between males and females. On the contrary, age was shown to have a significant positive correlation with fasting gallbladder volume, particularly in males. In a second group of 63 healthy volunteers gallbladder volumes were evaluated both before and after a standard meal. The subjects were grouped according to age, and fasting gallbladder volume appeared to be significantly greater in the groups formed by older people. Gallbladder volumes were compared in younger groups (under 35), and gallbladder emptying resulted to be much more complete in males than in females. On the contrary, no significant difference was observed between males and females over 50--which suggests a possible role of sex- and age-related hormonal factors. The above changes in gallbladder function may facilitate bile stasis which might in turn contribute to the increased risk for cholesterol gallstones notoriously associated with advanced age and female sex.     

Gallbladder function in diabetic patients

Gallbladder emptying and filling was studied in eight diabetic and six normal control patients. None of the patients had gallstones. Cholescintigraphy was performed using [99mTc]disofenin, and gallbladder emptying was studied using a 45-min i.v. infusion of the octapeptide of cholecystokinin (OP-CCK) 20 ng/kg X hr. The peak filling rate was greater in diabetic than in normal subjects; however, emptying of the gallbladder in response to OP-CCK was significantly less in the diabetic subjects (51.6 +/- 10.4% compared with 77.2 +/- 4.9%). When the diabetic group was subdivided into obese and nonobese diabetics, the obese diabetics had a much lower percentage of emptying than the nonobese diabetics (30.0 +/- 10.4% compared with 73.1 +/- 9.3%). These findings suggest that obese diabetics may have impaired emptying of the gallbladder even in the absence of gallstones. The more rapid rate of gallbladder filling in obesity may indicate hypotonicity of the gallbladder. The combination of these abnormalities may predispose the obese diabetic to the development of gallstones.     

Biliary motor function in gallstone patients evaluated by fatty-meal MR cholangiography

PURPOSE: To investigate the possibility of evaluating biliary motor function with magnetic resonance cholangiography (MRC). MATERIALS AND METHODS: Twenty patients with gallstones and 30 control subjects were studied using fatty-meal MRC. After baseline MRC, they were encouraged to drink 250 mL of milk and underwent postprandial MRC every 10 minutes for 60 minutes. Postprandial changes in gallbladder volume and the diameter of the common duct were assessed as indicators of gallbladder contractility and biliary obstruction, respectively. Postprandial dilatation at 60 minutes was considered indicative of persistent biliary obstruction. RESULTS: Gallbladder ejection fraction was calculated at 66.0% +/- 12.2% (range, 40.3%-88.6%) in the controls. Gallbladder volume expressed as a percentage of the baseline value was significantly larger at 20-60 minutes in the gallstone patients than in the controls. Gallbladder ejection fraction varied widely (mean, 46.4% +/- 24.4%; range, 2.8%-81.5%) and was significantly reduced in comparison with that of the controls (P < 0.01). In two gallstone patients with co-existing ductal stones, transient postprandial dilatation associated with ampullary impaction was observed. Persistent biliary obstruction was not indicated in any subjects. CONCLUSION: The results of this study suggest the feasibility of fatty-meal MRC, as well as its potential for evaluating biliary motor function.     

Motor function of the gallbladder: measurement and clinical significance

Abnormalities in gallbladder emptying commonly occur in gallstone patients. Similar changes can be found in patients without gallstones that have disease that may predispose to stones, such as diabetes. Decreased contractility of the gallbladder can be measured clinically with variety of radiological techniques, and ultrasonography seems to have a number of advantages over others. In addition to a role in pathogenesis, decreased gallbladder emptying may determine the clearance of gallstones from the gallbladder during dissolution and after lithotripsy.     

Segmentation of the gallbladder: effect on bile entry and exit and its clinical relevance in a patient with abdominal pain

BACKGROUND: The effects of folds or septa on gallbladder filling and emptying are not known. METHODS: Gallbladder filling and emptying were measured in seven patients with two chambers (segmental) and compared with 10 subjects with a single chamber (control). Percent bile flow into gallbladder, and percent ejection fraction from the proximal and distal segments, and entire gallbladder were measured with cholecystokinin. RESULTS: Bile entry into gallbladder was similar in both groups. In patients with segmentation, overall emptying was low mostly due to poor emptying of the distal segment. CONCLUSION: Segmentation of the gallbladder does not affect bile entry, but acting as a one-way valve, a fold or septum lowers emptying significantly, mostly from the distal segment.     

Gallbladder ejection fraction: correlation of scintigraphic and ultrasonographic techniques

PURPOSE: The assessment of gallbladder function and ejection fraction using sincalide-enhanced biliary scintigraphy is a useful way to evaluate patients with recurrent right upper quadrant pain but no gallstones. MATERIALS AND METHODS: We wanted to determine whether gallbladder contraction measured by ultrasonography could be used in place of biliary scintigraphy. Biliary scans with an infusion of sincalide and concurrent ultrasonography were performed in 17 patients with histories of recurrent abdominal pain and no evidence of gallstones by ultrasound. RESULTS: Gallbladder ejection fractions calculated by ultrasound and scintigraphy using standard techniques showed only a weak correlation. The poor performance of ultrasound appears to arise because the variable shape of the gallbladder invalidates the calculation of its volume by the formula for a prolate spheroid. When gallbladders that were ellipsoidal were subselected, correlation was improved. The level of training of the sonologist did not have a significant effect on the results. CONCLUSION: Gallbladder ejection fraction calculated by ultrasonography cannot be used routinely as a substitute for biliary scintigraphy.     

Normal gallbladder ejection fraction after morphine augmentation.

PURPOSE: Morphine sulfate causes spasm of the sphincter of Oddi. Conversely, the cholecystagogue sincalide produces relaxation of the sphincter and contraction of the gallbladder. This prospective study evaluated whether sincalide could produce normal gallbladder emptying after low-dose morphine sulfate (0.04 mg/kg). METHODS: Thirty to 120 minutes (mean, 51 minutes) after morphine sulfate-augmented gallbladder visualization, 25 gallbladder ejection fractions in 24 patients were measured. One patient was studied twice, 2 weeks apart. Gallbladder ejection fractions were calculated after controlled 30-minute infusions of sincalide (0.02 microg/kg). RESULTS: Fourteen gallbladder ejection fractions were normal (mean, 63%; range, 45% to 80%) and 11 gallbladder ejection fractions were abnormal (mean, 12%; range, 5% to 19%; P < 0.001). CONCLUSIONS: Normal gallbladder ejection fractions can be obtained as early as 30 minutes after administration of low-dose morphine sulfate. Potential applications of post-morphine sulfate sincalide challenge would include, for example, to support true-negative morphine sulfate-augmented gallbladder visualization in a patient with a high clinically indicated potential of having acute cholecystitis.     

Hepatic bile entry into and transit pattern within the gallbladder lumen: a new quantitative cholescintigraphic technique for measurement of its concentration function.

The aim of the project was to study hepatic bile entry into and the transit pattern within the gallbladder lumen during fasting and to introduce a new quantitative scintigraphic test for measurement of its concentration function. METHODS: Each of 10 control subjects and 10 chronic acalculous cholecystitis (CAC) patients received 111-185 MBq 99mTc-mebrofenin as a hepatic bile marker. Gamma-camera image data were collected in the anterior view on a 128 x 128 x 16 computer matrix at 1 frame per minute for 60 min for the hepatic phase and 30 min for the gallbladder phase. The radiolabeled hepatic bile area within the gallbladder lumen was traced, and the net transit area and transit time were noted. The hepatic bile transit rate was calculated (as mm2/min) and normalized to 1,000 mm2 of the anterior gallbladder area. The cholecystokinin-8-induced ejection fraction was calculated nongeometrically using counts. RESULTS: Hepatic bile entered the gallbladder continuously during fasting with a mean +/- SD of 71% +/- 20% in control subjects and 59% +/- 27% in CAC patients, which were not significantly different (P > 0.05). The maximum frontal gallbladder area was 1,699 mm2 in control subjects and 1,610 mm2 in CAC patients (P > 0.05). Radiolabeled hepatic bile entered the gallbladder first along its central long axis in both groups, at a mean of 15 min and 16 min, respectively, and traveled toward the periphery in a lamellar fashion at a normalized mean rate of 38 mm2/min and 40 mm2/min in control subjects and CAC patients, respectively. The mean ejection fraction of 17% in CAC patients was significantly lower than the mean value of 56% in control patients (P < 0.00001). CONCLUSION: Hepatic bile enters the gallbladder continuously during fasting. In patients with CAC, the gallbladder maintains the normal concentration function but the contraction and emptying are reduced significantly. This new cholescintigraphic technique enables measurement of both functions sequentially with a single dose of 99mTc-mebrofenin.     

Quantitative cholescintigraphy and bile abnormalities in patients with acalculous biliary pain

Acalculous biliary pain has been related to gallbladder dysfunction that produces a gallbladder emptying defect—a condition which favours the development of lithiasis. It is therefore probable that microlithiasis is present in patients with gallbladder dysfunction. The aims of this study were to measure gallbladder emptying and investigate bile abnormalities in patients with acalculous biliary pain. In 92 consecutive patients, gallbladder emptying was assessed by quantitative cholescintigraphy (abnormal ejection fraction 40%). In 64 patients, a microscopic study was performed on duodenal bile, defining abnormality as the presence of cholesterol crystals in any amount and/or calcium bilirubinate granules and/or microspheroliths at a rate of >10 per slide. The ejection fraction was abnormal in 45 patients (49%) (median 25.1%, range 6.8–39.3%) and normal in the remaining 47 cases (median 71.3%, range 41.0–96.1%). Bile was abnormal in 32 of 64 patients (50%), the most frequent finding being calcium bilirubinate granules. In the patients with bile abnormalities, abnormal ejection fraction was more frequent (20 of 32) and the median ejection fraction was lower (30.9%, range 12.0–94.1%) than in the patients with normal bile (16 of 32 with an abnormal ejection fraction; median ejection fraction 50.7%, range 6.8–96.1%). Abnormal bile was frequent (55.5%) in patients with reduced ejection fraction, but was not uncommon in patients with normal ejection fraction (33.3%). Fewer patients showed no alteration (25%). It is concluded that in most patients, acalculous biliary pain coexists with gallbladder dysfunction or abnormal bile, the combination of both alterations being common.     

99Tcm-EHIDA肝胆动态显像判断肝硬化患者胆囊运动功能

目的研究^99Tc^m-二乙基乙酰苯胺亚氨二醋酸（EHIDA）肝胆动态显像在判断肝硬化患者胆囊运动功能中的作用.方法研究对象分为正常对照组和肝硬化组,其中肝硬化组分为胆石组和非胆石组.受试者均行^99Tc^m-EHIDA肝胆动态显像.获得图像后应用胆囊感兴趣区（ROI）技术,由计算机自动绘制胆囊时间-放射性曲线,并计算潜伏期（LP）、排胆期（EP）、排胆分数（GBEF）和排胆率（ER）.结果肝硬化组患者GBEF和ER明显低于正常对照组（t值均为2.767,P均＜0.01）,但其LP高于正常对照组（Z=-1.989,P＜0.05）.肝硬化胆石组胆囊运动异常率（x^2=4.538,P=0.033）、胆囊壁厚度（t=-2.386,P=0.02）和血清总胆汁酸（t=-2.442,P=0.018）明显高于非胆石组.结论肝硬化患者胆囊运动功能减弱.^99Tc^m-EHIDA肝胆动态显像可作为检查胆囊运动功能的一种无创、准确的方法.     

Gallbladder function: methods for measuring filling and emptying

Cholescintigraphy with [99mTc] disofenin was used to determine the optimal dose and method of administration of the octapeptide of cholecystokinin, and to determine the kinetics of gallbladder filling and emptying in 22 patients without disease of the liver or gallbladder. The peak filling rate of the gallbladder occurred at 30 min after injection; filling was complete at 1 hr. A 45-min constant intravenous infusion of the octapeptide 20 ng/kg X hr resulted in progressive emptying of the normal gallbladder; the mean ejection fraction at 45 min was 77.2 +/- 4.9%. A 1-min injection of 20 ng/kg resulted in a rapid, short-lived emptying; the mean ejection fraction was 52.2 +/- 9.3%. Doubling or halving the infusion dose produced no greater response or a smaller response. We conclude that a constant 45-min infusion technique is superior to short injection times, because of more complete emptying, no side effects, and more consistent response.     

Corn oil emulsion: a simple cholecystagogue for diagnosis of chronic acalculous cholecystitis.

This study investigated the use of a corn oil emulsion as an inexpensive alternative to sincalide in the scintigraphic diagnosis of chronic acalculous cholecystitis (CAC). METHODS: Thirty patients with abdominal or right upper quadrant pain underwent (99m)Tc-disofenin hepatobiliary imaging for 60 min. After gallbladder filling, 30 mL of corn oil emulsion were administered orally to all patients followed by dynamic imaging for an additional 60 min in all patients and for 90 min in 26 patients. Gallbladder emptying kinetics were determined with gallbladder ejection fractions calculated at 30, 60, and 90 min. The results were compared with histopathologic or clinical follow-up data. RESULTS: Corn oil emulsion was found to be palatable and free of side effects in all patients. Seven of the 30 patients had histopathologic evidence of CAC, whereas the remaining 23 did not have evidence of gallbladder disease based on clinical follow-up. The 30-, 60-, and 90-min gallbladder ejection fractions were determined to be 25% +/- 22% (mean +/- SD), 47% +/- 28%, and 62% +/- 29%, respectively. Receiver-operating-characteristic analysis showed that the 60-min gallbladder ejection fraction best distinguished between CAC and non-gallbladder disease with an area under the curve of 0.963. A 60-min gallbladder ejection fraction of < or = 20% had 100% sensitivity, 96% specificity, 88% positive predictive value, 100% negative predictive value, and 97% overall accuracy for the diagnosis of CAC. CONCLUSION: Standardized corn oil emulsion appears to be an adequate and well-tolerated gallbladder stimulant. Based on receiver-operating-characteristic analysis, a 60-min gallbladder ejection fraction of < or = 20% using this simple cholecystagogue results in high diagnostic accuracy for CAC.     

Cholecystokinin cholescintigraphy: methodology and normal values using a lactose-free fatty-meal food supplement.

The purpose of this investigation was to evaluate the use of a commercially available lactose-free fatty-meal food supplement, as an alternative to sincalide cholescintigraphy, to develop a standard methodology, and to determine normal gallbladder ejection fractions (GBEFs) for this supplement. METHODS: Twenty healthy volunteers all had negative medical histories for hepatobiliary and gallbladder disease, had no personal or family history of hepatobiliary disease, and were not taking any medication known to affect gallbladder emptying. All were prescreened with a complete blood cell count, comprehensive metabolic profile, gallbladder and liver ultrasonography, and conventional cholescintigraphy. Three of the 20 subjects were eliminated from the final analysis because of an abnormality in one of the above studies. RESULTS: After gallbladder filling on conventional cholescintigraphy, the subjects ingested the supplement and an additional 60-min study was acquired. GBEFs were calculated and ranged from 33% to 95% (mean +/- SD, 62.6% +/- 21.3%). Statistical analysis determined the lower range of normal to be 32.6%. Maximal gallbladder emptying occurred between 55 and 60 min. CONCLUSION: A standard methodology and normal GBEFs (> or =33%) were established for supplement-stimulated cholescintigraphy.     

功能性消化不良患者的胆囊排空功能评价

目的探讨胆囊排空功能及胃肠激素水平变化在功能性消化不良(FD)发病机制中的作用.方法采用放射免疫分析法(RIA)和放射性核素显像法测定32例FD患者、20例健康志愿者空腹及脂餐后60min血浆胃动素(MTL)、胆囊收缩素(CCK)、血管活性肠肽(VIP)、生长抑素(SS)及胆囊排空功能,获得不同时相胆囊排空指数.结果FD组空腹及餐后胆囊排空指数、MTL均低于对照组,差异均有显著性(P均<0.001),且MTL与胆囊排空指数呈正相关(r空腹=0.82,r餐后=0.94,P均<0.01);FD组空腹血浆CCK与对照组比较差异无显著性(P>0.05),餐后低于对照组,差异有显著性(P<0.001),且餐后CCK与胆囊排空指数呈显著正相关(r=0.97,P<0.01);FD组空腹与餐后血浆VIP均高于对照组,差异有显著性(P<0.001),VIP与胆囊排空指数呈负相关(r空腹=-0.81,r餐后=-0.47,P均<0.01).FD组空腹及餐后血浆SS与对照组相比差异无显著性.结论FD患者(运动障碍型)存在空腹及餐后胆囊排空障碍.血浆促胃肠动力激素(MTL、CCK)水平下降和抑制胃肠动力激素(VIP)水平升高是FD患者胆囊排空障碍的病因和重要的病理生理基础.     

Altered gallbladder contractility after extracorporeal shock-wave cholecystolithotripsy

Change in gallbladder contractility after biliary extracorporeal shock-wave lithotripsy (ESWL) may significantly influence the clearance of fragments after successful gallstone fragmentation. We assessed changes in gallbladder contractility in response to an oral fatty meal in 50 patients 1 month after biliary ESWL (all fragments were smaller than 3 mm) and also in a separate group of 10 patients 3 months after complete clearance of fragments. The prevalence of persistent lumen-obliterating contraction of the gallbladder after biliary ESWL also was analyzed in 325 patients. Gallbladder contractility remained unchanged in 30, increased in nine, and decreased in 11 of the 50 patients. The average reduction in the fasting gallbladder volume after lithotripsy was 28% (p less than .001). Gallbladder contractility remained unchanged 3 months after complete clearance of fragments in six of 10 patients studied separately. A decrease (n = 2) or increase (n = 2) in contractility was seen in the remaining patients. No significant difference occurred in the average ejection fraction of the gallbladder before lithotripsy and after complete clearance of the fragments. Thirty-four of the 325 patients who have so far undergone biliary ESWL had a completely contracted gallbladder with no lumen visible on sonography. The gallbladder returned to a relaxed state in half of these patients within 1-9 months. Thus, biliary ESWL did not significantly alter gallbladder contractility in 60% of patients. A significant reduction in the volume of the fasting gallbladder occurred after lithotripsy. Successful clearance of fragments did not improve the contractility of stonebearing gallbladders in the majority of patients.     

Calculation of a gallbladder ejection fraction: advantage of continuous sincalide infusion over the three-minute infusion method.

The purpose of this study was to investigate alternative methods of infusing sincalide for calculation of a gallbladder ejection fraction (GBEF) during cholescintigraphy (5 mCi 99mTc-mebrofenin). After gallbladder filling, three methods of infusion were compared in 23 normal volunteers: (1) 0.02 microgram/kg as a 3-min infusion, (2) 0.02 microgram/kg as a 30-min infusion, and (3) 0.01 microgram/kg as a 30-min infusion (14 subjects), all performed on separate days. With the 3-min infusion, the emptying pattern was usually exponential and completed in 15 min. The mean (GBEF) was 52% +/- 26% at 20 min and 56% +/- 27% at 30 min (range 0%-100%). GBEFs were less than 35% in six subjects and 35%-38% in four. Side effects were noted by 11/23 subjects. With the slow infusions, emptying was linear; no side effects were noted. With 0.02 microgram/kg, the mean GBEF was 50% +/- 27% at 20 min and 70% +/- 22% at 30 min (range 26%-95%). Similar results were seen with 0.01 microgram/kg, but the data were more limited. The 30-min infusion had a higher normalcy rate than the 3-min method (91% versus 74%). Females had significantly lower GBEFs than males (p less than 0.05%). We conclude that the slow infusion method is preferable; it is more physiological, results in more complete emptying, has no side effects, has less normal variability, and should improve the specificity of this test. The lower mean female GBEF may have pathophysiological significance.     

Characterization of basal hepatic bile flow and the effects of intravenous cholecystokinin on the liver,sphincter, and gallbladder in patients with sphincter of Oddi spasm

The major objectives of this project were to establish the pattern of basal hepatic bile flow and the effects of intravenous administration of cholecystokinin on the liver, sphincter of Oddi, and gallbladder, and to identify reliable parameters for the diagnosis of sphincter of Oddi spasm (SOS). Eight women with clinically suspected sphincter of Oddi spasm (SOS group), ten control subjects (control group), and ten patients who had recently received an opioid (opioid group) were selected for quantitative cholescintigraphy with cholecystokinin. Each patient was studied with 111–185 MBq (3–5 mCi) technetium-99m mebrofenin after 6–8 h of fasting. Hepatic phase images were obtained for 60 min, followed by gallbladder phase images for 30 min. During the gallbladder phase, 10 ng/kg octapeptide of cholecystokinin (CCK-8) was infused over 3 min through an infusion pump. Hepatic extraction fraction, excretion half-time, basal hepatic bile flow into the gallbladder, gallbladder ejection fraction, and post-CCK-8 paradoxical filling (>30% of basal counts) were identified. Seven of the patients with SOS were treated with antispasmodics (calcium channel blockers), and one underwent endoscopic sphincterotomy. Mean (±SD) hepatic bile entry into the gallbladder (versus GI tract) was widely variable: it was lower in SOS patients (32%±31%) than in controls (61%±36%) and the opioid group (61%±25%), but the difference was not statistically significant. Hepatic extraction fraction, excretion half-time, and pattern of bile flow through both intrahepatic and extrahepatic ducts were normal in all three groups. Gallbladder mean ejection fraction was 9%±4% in the opioid group; this was significantly lower (P<0.0001) than the values in the control group (54%±18%) and the SOS group (48%±29%). Almost all of the bile emptied from the gallbladder refluxed into intrahepatic ducts; it reentered the gallbladder after cessation of CCK-8 infusion (paradoxical gallbladder filling) in all eight patients with SOS, but in none of the patients in the other two groups. Mean paradoxical filling was 204% (±193%) in the SOS group and less than 5% (P<0.05) in both the control and the opioid group. After treatment, six of the SOS patients had complete pain relief and one, partial pain relief. The basal tonus of the sphincter is variable in patients with SOS, and allows relatively more of the hepatic bile to enter the GI tract than the gallbladder. Due to simultaneous contraction of the sphincter and gallbladder in response to CCK-8, most of the bile emptied from the gallbladder refluxes into intrahepatic ducts, and reenters the gallbladder immediately after cessation of hormone infusion. The characteristic features of gallbladder filling, emptying, and paradoxical refilling with cholecystokinin provide objective parameters for noninvasive diagnosis of SOS by quantitative cholescintigraphy.