Gallbladder ejection fraction: correlation of scintigraphic and ultrasonographic techniques

Cholecystokinin-cholescintigraphy in adults: consensus recommendations of an interdisciplinary panel

BACKGROUND AND AIMS

Cholecystokinin-cholescintigraphy (CCK-CS) provides a physiologic, noninvasive, and quantitative method for assessing gallbladder contraction and calculation of a gallbladder ejection fraction (GBEF). At present, it is used most commonly to identify patients with suspected functional gallbladder disorder. However, the methodology of CCK infusion and normal values differ markedly among imaging centers.

METHODS

This document represents the consensus opinion of an interdisciplinary panel that gathered to assess the current optimal method for performing CCK-CS in adults, potential uses and limitations of CCK-CS, and questions that require further investigation.

RESULTS

The panel recommended the use of a single, standardized, recently described CCK-CS protocol that involves infusion of 0.02 μg/kg of sincalide over 60 minutes with a normal GBEF defined as ≥38%. The panel emphasized the need for a large, multicenter, prospective clinical trial to establish the utility of CCK-CS in the diagnosis of functional gallbladder disease. Although not without controversy regarding its clinical utility, the primary indication for CCK-CS at present is the well-selected patient with suspected functional gallbladder disorder.

CONCLUSION

Agreement was reached that the adoption of this standardized protocol is critical to improve how CCK-CS is used to direct patient care and will represent an improvement over the diverse methods currently in use by eliminating the current lack of uniformity and adding both reliability and credibility to the results.

Cholecystokinin-cholescintigraphy in adults: consensus recommendations of an interdisciplinary panel

BACKGROUND & AIMS

Cholecystokinin-cholescintigraphy (CCK-CS) provides a physiologic, noninvasive, and quantitative method for assessing gallbladder contraction and calculation of a gallbladder ejection fraction (GBEF). At present, it is used most commonly to identify patients with suspected functional gallbladder disorder. However, the methodology of CCK infusion and normal values differ markedly among imaging centers.

METHODS

This document represents the consensus opinion of an interdisciplinary panel that gathered to assess the current optimal method for performing CCK-CS in adults, potential uses and limitations of CCK-CS, and questions that require further investigation.

RESULTS

The panel recommended the use of a single, standardized, recently described CCK-CS protocol that involves infusion of 0.02 μg/kg of sincalide over 60 minutes with a normal gallbladder ejection fraction defined as ≥38%. The panel emphasized the need for a large, multicenter, prospective clinical trial to establish the utility of CCK-CS in the diagnosis of functional gallbladder disease. Although not without controversy regarding its clinical utility, the primary indication for CCK-CS at present is the well-selected patient with suspected functional gallbladder disorder.

CONCLUSIONS

Agreement was reached that the adoption of this standardized protocol is critical to improve how CCK-CS is used to direct patient care and will represent an improvement over the diverse methods currently in use by eliminating the current lack of uniformity and adding both reliability and credibility to the results.

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.

Evaluation of Body Surface Area as a Determinant of Cholecystodynamics Due to Orally Administered Standardized Skimmed Milk

The author studied the relationship between body surface area and both the gallbladder contraction index and gallbladder emptying rate. Using the ellipsoid formula, gallbladder volumes were sonographically measured in the preprandial state and 20 minutes after a standardized fatty meal in 62 subjects. Gallbladder contraction indices and emptying rates were calculated. The body surface area of 61 subjects who followed the study design was computed from their height and weight measurements. Parametric tests also were carried out, revealing that there were no significant correlations between body surface area and gallbladder contraction index and gallbladder emptying rate. Dosing in cholecystodynamic studies may be limited by lack of correlation between gallbladder emptying rate and body surface area.

Acalculous biliary tract disorders: the value of fatty meal-cholescintigraphy

BACKGROUND

The management of patients with symptoms consistent with biliary tract disease but without evidence of cholelithiasis is difficult. This study was undertaken to test the value of cholescintigraphy in predicting the success of cholecystectomy in patients with acalculous biliary tract disorders.

MATERIAL AND METHODS

A prospective study was carried out on 73 patients presenting with recurrent upper quadrant pain without documented evidence of gallstones on ultrasound. Fatty meal-cholescintigraphy was performed on all patients and the gallbladder ejection fraction was calculated. Laparoscopic cholecystectomy was performed in patients with ejection fractions of <40%, followed by histopathological analysis and assessment of symptomatic improvement.

RESULTS

There were 43 men and 30 women with a mean age of 33.4 years. Forty-one patients had abnormal ejection fractions. All except one patient had a laparoscopic cholecystectomy. The pathological diagnosis of chronic cholecystitis was made in 33 patients and acute on chronic cholecystitis documented in four patients. Five patients had cholesterolosis and two of these had associated chronic cholecystitis. All except three patients had complete relief of symptoms post-operatively with a mean follow-up of 10 months.

CONCLUSION

Modified cholescintigraphy is a useful test for predicting which patients with acalculous biliary tract disease benefit from a cholecystectomy.

[Dynamic ultrasonography in the diagnosis of gallbladder dysfunction: reliability of a simple method with easy clinical application]

AIMS

Although the results of dynamic ultrasonography (DUS) are similar to those of dynamic cholescintigraphy (DCS) in the study of gallbladder function, the methodology required for this technique is laborious and sometimes complex. The aim of this study was to investigate the reliability of a simple method of DUS to evaluate gallbladder function using DCS as a reference.

PATIENTS AND METHODS

Gallbladder function was studied using DUS and DCS in 80 consecutive patients with clinical findings compatible with gallbladder dysfunction. For DUS the ellipsoid method was used with measurement of three gallbladder diameters (transversal, longitudinal and anteroposterior) in basal conditions and after applying a cholecystokinetic stimulus (meal test); gallbladder emptying of less than 50% was considered abnormal. In DCS intravenous cholecystokinin (CCK) (0.40 IDU/kg in 20 minutes) was used as stimulus and an ejection fraction < or = 40% was considered abnormal.

RESULTS

In 15 patients (19%; 95% CI, 11-29%) abnormal gallbladder response was found using DUS. The ejection fraction in the entire group of patients studied was 48 26.2%. Ejection fraction was abnormal in 41 patients (51%; 95% IC, 40-63%) with a value of 25 8.5% and was normal in 39 patients (49%; 95% IC, 40-63%) with a value of 71.5 14.5%. The correlation coefficient between the values of gallbladder emptying calculated with DUS and the ejection fraction obtained with DCS was 0.199 (p = 0.079). When patients were divided according to gallbladder emptying measured by DUS and the ejection fraction obtained with DCS the concordance was very low (k = 0.065; EE = 0.085).

CONCLUSIONS

DUS performed using a simple technique lacks diagnostic value in gallbladder dysfunction when DCS is taken as a reference test

Does Gallbladder Ejection Fraction Predict Pathology after Elective Cholecystectomy for Symptomatic Cholelithiasis ?

Patients with symptomatic cholelithiasis are selected for elective cholecystectomy with the expectation that their symptoms will improve after operation. However, some patients fail to improve because their preoperative symptoms were not related to gallbladder disease. A test that would indicate the severity of gallbladder disease in patients with gallstones would therefore have great potential benefit. Twenty-five patients who presented as outpatients with episodic abdominal pain and gallstones were scheduled for elective cholecystectomy. On the day before operation patients underwent nuclear medicine cholescintigraphy with measurement of ejection fraction. All patients then underwent laparoscopic cholecystectomy. Pathologic specimens were reviewed by a pathologist who was blinded to the ejection fraction results and scored for degree of inflammation on a scale of zero to three. There was a wide range of ejection fractions measured (0–84%). There was, however, no correlation between ejection fractions and degree of gallbladder inflammation. We conclude that gallbladder ejection fraction does not predict the degree of gallbladder inflammation at the time of elective cholecystectomy. This test is therefore unlikely to predict which patients with cholelithiasis will have symptomatic relief after cholecystectomy.

Estimation of gallbladder ejection fraction utilizing cholecystokinin-stimulated magnetic resonance cholangiography and comparison with hepatobiliary scintigraphy

PURPOSE

To evaluate the utility of magnetic resonance cholangiography (MRC) in estimation of gallbladder ejection fraction (GBEF) and to comparing this value to the conventional method, hepatobiliary scintigraphy (HBS).

MATERIALS AND METHODS

Twenty-one healthy volunteers were imaged on sequential weeks to determine GBEF using MRC and HBS. GBEF was calculated by HBS after infusion of 20 ng/kg of sincalide following injection of 111 Mbq of Tc 99(m) mebrofenin. For estimation by MRC, imaging of the gallbladder was performed before and after slow infusion of sincalide every 5 minutes, for a total of 60 minutes. Gallbladder imaging was performed using a heavily T2-weighted 2D fast spin echo (FSE) sequence. Data was analyzed using a variance component analysis technique.

RESULTS

Mean GBEF by HBS was 65.7%, with an SD of +/-27.3%. Mean GBEF by MRC was 62.7%, with an SD of +/- 20.4%. If minimum normal GBEF is set at 35%, two of the cases showed discordance, with HBS calculating an abnormally low average GBEF compared to MRC. Additionally, two cases showed abnormally low GBEF for both modalities. The coefficient of correlation between HBS and MRC was 0.72. Inter- and intraobserver variance is acceptable within the two modalities with <1.1% variation.

CONCLUSION

GBEF can be calculated with MRC, yielding similar values when a group of volunteers are considered. Further study with symptomatic patients is needed to determine the validity of this technique for clinical diagnosis.