Clin. RadioL (1976) 27, 117-121 THE VALUE OF THE FATTY MEAL IN ORAL CHOLECYSTOGRAPHY I. C. HARVEY,* MYO THWE'~ and T. S. LOW-BEER~
From the Departments of Radiology and Medicine, United Bristol Hospitals and University of Bristol In order to assess the value of the after fatty meal films, 232 oral cholecystograms were reviewed. Gallbladder opacification, duct visualisation, separation of gallbladder from overlying bowel gas shadows, and the demonstration of abnormalities were assessed from the pre-fatty meal films, and then again in conjunction with those taken after fat, when contraction was also assessed. Of the 200 examinations given the fatty meal, 132 were adjudged normal, 63 had gallstones, four had adenomyomatosis (one with stones), and two cholesterolosis. The post-fatty meal films were found to be essential for the diagnosis of adenomyomatosis and cholesterolosis, and considered to be occasionally helpful in diagnosing small stones. They were of little value in assessing the biliary ducts, or separating the gallbladder from overlying bowel gas, and of no value in the diagnosis of functional biliary tract disorders.
ORALcholecystography has been described as one of the most reliable methods of radiological investigation (Ericksson and Saltzmann, 1970). The practice of stimulating the contrast-filled gallbladder to contract is practically universal in England and Wales (Heaton and Gibson, 1973). There is, however, no general agreement amongst radiologists, or the standard radiological textbooks, regarding the value of this procedure. Suggested indications include the detection of previously invisiblegallbladder lesions (Sutton, 1969; Hodgson, 1970); the demonstration of biliary ducts (Hodges and Whitehouse, 1965); the separation of the gallbladder from bowel gas shadows (Miller et al., 1974); and the detection of functional biliary tract disorders (Heaton and Gibson, 1973). An unselected series of 232 cholecystograms was reviewed in order to assess the validity of these indications.
wards or general practitioners because gallbladder disease was suspected. The cholecystogram comprised four sets of films; a preliminary film; a prone oblique film, taken 12 h after ingestion of 3 g of sodium ipodate (Biloptin, Schering); then serial erect films under fluoroscopic control; and a prone oblique film taken 30 rain after a fatty meal, which consisted of 60 ml of 50 % Arachis oil in a flavoured base. The pre-fatty meal films were inspected, and an opinion recorded. The post-fatty meal film was then examined, and the original opinion either confirmed or altered. The films were assessed for the degree of opacification, contraction, duct visualisation, bowel gas overlying the gallbladder, and the demonstration of abnormalities. RESULTS
In 23 of the 232 patients examined, the gallbladder failed to opacify. A fatty meal was not Unselected cholecystograms of 158 women, aged given to these, or to a further nine, most of whom 18-78 (average 49 years), and 74 men, aged 26-71 had stones visible on the pre-fatty meal films. Of the 200 patients given the fatty meal, 63 had (average 49 years), were examined. These patients gallstones; four adenomyomatosis, one associated were referred from hospital out-patient clinics, with stones; two cholesterolosis; and no abnormality was detected in 132. The diagnosis of *Present address: Royal County Isle of Wight Hospital, gallstones was confirmed in all 46 patients who Ryde. ~Present address: Institute of Medicine, 2 Rangoon, underwent cholecystectomy. Two of the patients were found to have stones in the common bile duct, Burma. and a further one had a stone in the cystic duct. Present address: SellyOak Hospital, Birmingham. 117 PATIENTS AND METHODS
118
CLINICAL RADIOLOGY
Opacification was graded as either good or poor. 8 7 ~ of the normal examinations showed good opacification, compared with 6 2 ~ of those with stones. Gallbladder opacification improved after fat in 5"5~o of normal patients, and 11 ~ with stones (Table 1). Contraction was assessed in two categories: (1) good or moderate; (ii) absent or minimal (Low-Beer et al., 1971). Good or moderate contraction occurred in 82-5 ~ of radiologically normal gallbladders, and 6 5 ~ of those with stones (P < 0.05) (Table 2). Duct opacification was not detectable in 41 ~ of cases. The ducts were opacified before the fatty meal in 2 1 ~ with stones compared to 6 ~ of
normals (P< 0.01). Some improvement in opacifi. cation of the ducts after fat was seen in 52 ~ of normal cholecystograms and 4 6 ~ with stones, although the degree of opacification was variable, and frequently insufficient for diagnostic purposes (Table 3). Gallstones were recognised on the pre-fatty meals films in 63 patients. The after-fatty meal films revealed no additional cases. No stones were seen in the biliary ducts. Bowel gas was differentiated from gallstones by appropriate positioning of the patient for the serial erect films, where stones were seen either to sink to the bottom of the gallbladder, or to form a layer of floating stones. Both the 12 h prone oblique and the post-fatty meal film were taken in the same position, TABLE 1 and overlying bowel gas was similar on both films. THE DEGREE OF O PACIFICATIONOF RADIOLOGICALLYNORMAL Adenomyomatosis was recognised by a thick GALLBLADDERS, COMPARED WITH THOSE WITH STONES, AND THE INCIDENCE OF IMPROVEMENT SEEN AFTER THE FATTY gallbladder septum, good contraction of the MEAL affected portion, and the opacification of Roki. tansky-Aschoff sinuses (Colquhoun, 1961). Of the four cases, one was regarded as normal on the preOpacification of the gallbladder fatty meal films, apart from a proximal septum, but Normal Stones the post-fat film showed filling of the RokitanskyAschoff sinuses (Fig. I). Another showed a distal Good 115 ( 8 5 - 0 ~ ) 39 (62"0 ~ ) loculus which was seen to contract vigorously after Poor 10 ( 7 . 5 ~ ) 17 (27"0 ~ ) fat (Fig. 2). The other two were suspected before the Improved after fat 7 (5.5 ~ ) 7 (11-0~) fatty meal, and the diagnosis established on the post-fat films. Cholesterolosis was identified by fixed mural TABLE 2 filling defects. One of the two cases was suspected THE DEGREE OF GALLBLADDER CONTRACTION IN RESPONSE TO FAT IN RADIOLOGICALLY NORMAL GALLBLADDERS on the pre-fatty meal films, and the diagnosis of COMPARED WITH THOSE WITH GALLSTONES both established after fat (Fig. 3). Contraction after fat
Good/Moderate Absent/Minimal
Normal
Stones
109 (82.5 ~o) 23 (17" 5 ~ )
41 (65.0 ~ ) 22 ( 3 5 . 0 ~ )
TABLE 3 THE INCIDENCE OF DUCT VISUALISATION]3EFORE AND AFTER THE FATTY MEAL
Duct visualisation
Opacified before the fatty meal Opacified only after the fatty meal Never opacified
Normal
Stones
8 (6'0~)
13 (21"0,2/oo)
66 (50' 0 ~)
26 (41 '0~o)
58 (44-0 ~)
24 (38" 0 ~ )
DISCUSSION The most benefit from the post-fatty meal films has been obtained in the diagnosis of adenomyomatosis and cholesterolosis, both of which may appear as normal before contraction of the gallbladder (Figs. 1, 3). On rare occasions, stones may be seen on the post-fatty meal films alone (Hodgson, 1970), but the present study did not provide an example. Since the ducts are so inconstantly and inadequately opacified, stones in the biliary ducts cannot be excluded by oral cholecystography. Although stones in the biliary ducts were never seen at cholecystography in this survey, three patients were found to have them at operation within seven months of the investigation. To show the ducts more successfully, several films may have to be taken after the fatty meal (Hodges and Whitehouse, 1965). However, if lesions in the ducts are suspected,
THE V A L U E OF THE F A T T Y MEAL IN ORAL C H O L E C Y S T O G R A P H Y
FIG. 1 a. Adenomyomatosis. Before fat, showing a relatively normal gallbladder, with a possible proximal septum. B. After fat, showing good contraction with demonstration of Rokitansky-Aschoff sinuses.
FIG. 2 a. Adenomyomatosis. Before fat, showing a distal septum, with a small nodule on its left end. B. Good contraction of the affected distal portion, typical of adenomyomatosis.
119
120
CLINICAL RADIOLOGY
Fie. 3 A. Cholesterolosis. Before fat, showing a single small translucency within the gallbladder. B. After fat, showing good contraction with several filling defects, which were fixed to the wall on an erect film. FrG. 4 (left) Relatively poor opacification in a gallbladder filled with stones. The volume in which the contrast medium can accumulate is inadequate to achieve better opacification.
infusion choledochography is the investigation of choice (Margulis, 1967). The increased incidence of duct visualisation before the fatty meal when gallstones are present cannot be explained by the presence of choledochal stones. It is more likely to be due to failure of the gallbladder to accumulate the contrast medium, possibly enhanced by reabsorption of deconjugated material from the colon. The post-fatty meal film was of little benefit in separating the opacified gallbladder from overlying bowel gas. This is best achieved by change of posture, either by rotating the patient in the erect position, as in this series, or by taking decubitus films (Miller et aL, 1974). In either case contraction of the gallbladder is not necessary. Gallbladder function is generally assessed radiologically by the ability of the gallbladder to accumulate and concentrate the contrast medium, and then to expel it in response to an appropriate stimulus, such as a fatty meal. We have shown that
THE VALUE OF THE FATTY MEAL IN ORAL C H O L E C Y S T O G R A P H Y
the gallbladder fails to contract twice as c o m m o n l y in those with gallstones than in those without (Table 3). However, absence o f gallbladder contraction is not necessarily abnormal (Paul and Juhl, 1965), and occurs in one in six normal subjects (Low-Beer et al., 1971). This cannot, therefore, be used as evidence for diagnosing functional biliary tract disorders. P o o r opacification in the presence of stones is generally considered to be due to inability o f the gallbladder to admit or concentrate the contrast medium. Occasionally it m a y be due to lack o f volume for the contrast to accumulate (Fig. 4).
121
Acknowledgements. - We wish to thank Dr John Roylance for his considerable help and encouragement in the writing of this paper. REFERENCES
CONCLUSIONS
COLQtmOtJN,J. (1961). Adenomyomatosis of the gallbladder. British Journal o_[Radiology, 34, 101-112. EglKSSON,S. & SALTZMANN,G.-F. (1970). Residual contrast medium in the intestines and side effects during cholecystography. Acta Radiologica, 10, 69-75. HeATON, K. W. & GmSON, M. J. (1973). The use of 'fatty meals' in oral cholecystography: report of a postal survey in England and Wales. Clinical Radiology, 24, 90-94. HODGES, F. J. & WHITEHOUSE,W. M. (1965). The Gastrointestinal Tract: A Handbook of Roentgen Diagnosis, 2nd ed. Year Book Medical Publishers, Chicago. Hoo~soN, J. R. (1970). The technical aspects of cholecystography. Radiological Clinics of North America, 8 (1), 85-97.
The fatty meal is essential for the diagnosis of adenomyomatosis and cholesterolosis, and m a y occasionally be helpful in revealing small stones. The post-fatty meal films are o f little help in assessing the biliary ducts, or separating the opacifled gallbladder f r o m overlying bowel gas, and are o f no help in diagnosing functional biliary tract disorders. The biliary ducts are more likely to be opacified before the fatty meal in the presence of gallstones.
A. E. (1971). Gallbladder inertia and sluggish enterohepatic circulation of bile salts in coeliac disease. Lancet, 1, 991-994. MARCEl.IS, A. R. & BURHENNE, H. J. (1967) (Editors). Alimentary Tract Roentgenology. Mosby, St Louis. MmLER, R. E., CEml~NISH,S. M. & RODDA, B. E. (1974). Cholecystography: a cost reduction study. Radiology, 110, 61-65. PAUL,L. W. & JUHL,J. H. (1965). The Essentials of Roentgen Interpretation, 2rid edn. Harpter and Row, New York. StrrTON, D. & GRAINGER,R. H. (1969) (Editors). Textbook of Radiology. Livingstone, Edinburgh.
Low-BEER, T. S., HEATON, K. W., HEATON, S. T. ¢~ READ,
From the Departments of Radiology and Medicine, United Bristol Hospitals and University of Bristol In order to assess the value of the after fatty meal films, 232 oral cholecystograms were reviewed. Gallbladder opacification, duct visualisation, separation of gallbladder from overlying bowel gas shadows, and the demonstration of abnormalities were assessed from the pre-fatty meal films, and then again in conjunction with those taken after fat, when contraction was also assessed. Of the 200 examinations given the fatty meal, 132 were adjudged normal, 63 had gallstones, four had adenomyomatosis (one with stones), and two cholesterolosis. The post-fatty meal films were found to be essential for the diagnosis of adenomyomatosis and cholesterolosis, and considered to be occasionally helpful in diagnosing small stones. They were of little value in assessing the biliary ducts, or separating the gallbladder from overlying bowel gas, and of no value in the diagnosis of functional biliary tract disorders.
ORALcholecystography has been described as one of the most reliable methods of radiological investigation (Ericksson and Saltzmann, 1970). The practice of stimulating the contrast-filled gallbladder to contract is practically universal in England and Wales (Heaton and Gibson, 1973). There is, however, no general agreement amongst radiologists, or the standard radiological textbooks, regarding the value of this procedure. Suggested indications include the detection of previously invisiblegallbladder lesions (Sutton, 1969; Hodgson, 1970); the demonstration of biliary ducts (Hodges and Whitehouse, 1965); the separation of the gallbladder from bowel gas shadows (Miller et al., 1974); and the detection of functional biliary tract disorders (Heaton and Gibson, 1973). An unselected series of 232 cholecystograms was reviewed in order to assess the validity of these indications.
wards or general practitioners because gallbladder disease was suspected. The cholecystogram comprised four sets of films; a preliminary film; a prone oblique film, taken 12 h after ingestion of 3 g of sodium ipodate (Biloptin, Schering); then serial erect films under fluoroscopic control; and a prone oblique film taken 30 rain after a fatty meal, which consisted of 60 ml of 50 % Arachis oil in a flavoured base. The pre-fatty meal films were inspected, and an opinion recorded. The post-fatty meal film was then examined, and the original opinion either confirmed or altered. The films were assessed for the degree of opacification, contraction, duct visualisation, bowel gas overlying the gallbladder, and the demonstration of abnormalities. RESULTS
In 23 of the 232 patients examined, the gallbladder failed to opacify. A fatty meal was not Unselected cholecystograms of 158 women, aged given to these, or to a further nine, most of whom 18-78 (average 49 years), and 74 men, aged 26-71 had stones visible on the pre-fatty meal films. Of the 200 patients given the fatty meal, 63 had (average 49 years), were examined. These patients gallstones; four adenomyomatosis, one associated were referred from hospital out-patient clinics, with stones; two cholesterolosis; and no abnormality was detected in 132. The diagnosis of *Present address: Royal County Isle of Wight Hospital, gallstones was confirmed in all 46 patients who Ryde. ~Present address: Institute of Medicine, 2 Rangoon, underwent cholecystectomy. Two of the patients were found to have stones in the common bile duct, Burma. and a further one had a stone in the cystic duct. Present address: SellyOak Hospital, Birmingham. 117 PATIENTS AND METHODS
118
CLINICAL RADIOLOGY
Opacification was graded as either good or poor. 8 7 ~ of the normal examinations showed good opacification, compared with 6 2 ~ of those with stones. Gallbladder opacification improved after fat in 5"5~o of normal patients, and 11 ~ with stones (Table 1). Contraction was assessed in two categories: (1) good or moderate; (ii) absent or minimal (Low-Beer et al., 1971). Good or moderate contraction occurred in 82-5 ~ of radiologically normal gallbladders, and 6 5 ~ of those with stones (P < 0.05) (Table 2). Duct opacification was not detectable in 41 ~ of cases. The ducts were opacified before the fatty meal in 2 1 ~ with stones compared to 6 ~ of
normals (P< 0.01). Some improvement in opacifi. cation of the ducts after fat was seen in 52 ~ of normal cholecystograms and 4 6 ~ with stones, although the degree of opacification was variable, and frequently insufficient for diagnostic purposes (Table 3). Gallstones were recognised on the pre-fatty meals films in 63 patients. The after-fatty meal films revealed no additional cases. No stones were seen in the biliary ducts. Bowel gas was differentiated from gallstones by appropriate positioning of the patient for the serial erect films, where stones were seen either to sink to the bottom of the gallbladder, or to form a layer of floating stones. Both the 12 h prone oblique and the post-fatty meal film were taken in the same position, TABLE 1 and overlying bowel gas was similar on both films. THE DEGREE OF O PACIFICATIONOF RADIOLOGICALLYNORMAL Adenomyomatosis was recognised by a thick GALLBLADDERS, COMPARED WITH THOSE WITH STONES, AND THE INCIDENCE OF IMPROVEMENT SEEN AFTER THE FATTY gallbladder septum, good contraction of the MEAL affected portion, and the opacification of Roki. tansky-Aschoff sinuses (Colquhoun, 1961). Of the four cases, one was regarded as normal on the preOpacification of the gallbladder fatty meal films, apart from a proximal septum, but Normal Stones the post-fat film showed filling of the RokitanskyAschoff sinuses (Fig. I). Another showed a distal Good 115 ( 8 5 - 0 ~ ) 39 (62"0 ~ ) loculus which was seen to contract vigorously after Poor 10 ( 7 . 5 ~ ) 17 (27"0 ~ ) fat (Fig. 2). The other two were suspected before the Improved after fat 7 (5.5 ~ ) 7 (11-0~) fatty meal, and the diagnosis established on the post-fat films. Cholesterolosis was identified by fixed mural TABLE 2 filling defects. One of the two cases was suspected THE DEGREE OF GALLBLADDER CONTRACTION IN RESPONSE TO FAT IN RADIOLOGICALLY NORMAL GALLBLADDERS on the pre-fatty meal films, and the diagnosis of COMPARED WITH THOSE WITH GALLSTONES both established after fat (Fig. 3). Contraction after fat
Good/Moderate Absent/Minimal
Normal
Stones
109 (82.5 ~o) 23 (17" 5 ~ )
41 (65.0 ~ ) 22 ( 3 5 . 0 ~ )
TABLE 3 THE INCIDENCE OF DUCT VISUALISATION]3EFORE AND AFTER THE FATTY MEAL
Duct visualisation
Opacified before the fatty meal Opacified only after the fatty meal Never opacified
Normal
Stones
8 (6'0~)
13 (21"0,2/oo)
66 (50' 0 ~)
26 (41 '0~o)
58 (44-0 ~)
24 (38" 0 ~ )
DISCUSSION The most benefit from the post-fatty meal films has been obtained in the diagnosis of adenomyomatosis and cholesterolosis, both of which may appear as normal before contraction of the gallbladder (Figs. 1, 3). On rare occasions, stones may be seen on the post-fatty meal films alone (Hodgson, 1970), but the present study did not provide an example. Since the ducts are so inconstantly and inadequately opacified, stones in the biliary ducts cannot be excluded by oral cholecystography. Although stones in the biliary ducts were never seen at cholecystography in this survey, three patients were found to have them at operation within seven months of the investigation. To show the ducts more successfully, several films may have to be taken after the fatty meal (Hodges and Whitehouse, 1965). However, if lesions in the ducts are suspected,
THE V A L U E OF THE F A T T Y MEAL IN ORAL C H O L E C Y S T O G R A P H Y
FIG. 1 a. Adenomyomatosis. Before fat, showing a relatively normal gallbladder, with a possible proximal septum. B. After fat, showing good contraction with demonstration of Rokitansky-Aschoff sinuses.
FIG. 2 a. Adenomyomatosis. Before fat, showing a distal septum, with a small nodule on its left end. B. Good contraction of the affected distal portion, typical of adenomyomatosis.
119
120
CLINICAL RADIOLOGY
Fie. 3 A. Cholesterolosis. Before fat, showing a single small translucency within the gallbladder. B. After fat, showing good contraction with several filling defects, which were fixed to the wall on an erect film. FrG. 4 (left) Relatively poor opacification in a gallbladder filled with stones. The volume in which the contrast medium can accumulate is inadequate to achieve better opacification.
infusion choledochography is the investigation of choice (Margulis, 1967). The increased incidence of duct visualisation before the fatty meal when gallstones are present cannot be explained by the presence of choledochal stones. It is more likely to be due to failure of the gallbladder to accumulate the contrast medium, possibly enhanced by reabsorption of deconjugated material from the colon. The post-fatty meal film was of little benefit in separating the opacified gallbladder from overlying bowel gas. This is best achieved by change of posture, either by rotating the patient in the erect position, as in this series, or by taking decubitus films (Miller et aL, 1974). In either case contraction of the gallbladder is not necessary. Gallbladder function is generally assessed radiologically by the ability of the gallbladder to accumulate and concentrate the contrast medium, and then to expel it in response to an appropriate stimulus, such as a fatty meal. We have shown that
THE VALUE OF THE FATTY MEAL IN ORAL C H O L E C Y S T O G R A P H Y
the gallbladder fails to contract twice as c o m m o n l y in those with gallstones than in those without (Table 3). However, absence o f gallbladder contraction is not necessarily abnormal (Paul and Juhl, 1965), and occurs in one in six normal subjects (Low-Beer et al., 1971). This cannot, therefore, be used as evidence for diagnosing functional biliary tract disorders. P o o r opacification in the presence of stones is generally considered to be due to inability o f the gallbladder to admit or concentrate the contrast medium. Occasionally it m a y be due to lack o f volume for the contrast to accumulate (Fig. 4).
121
Acknowledgements. - We wish to thank Dr John Roylance for his considerable help and encouragement in the writing of this paper. REFERENCES
CONCLUSIONS
COLQtmOtJN,J. (1961). Adenomyomatosis of the gallbladder. British Journal o_[Radiology, 34, 101-112. EglKSSON,S. & SALTZMANN,G.-F. (1970). Residual contrast medium in the intestines and side effects during cholecystography. Acta Radiologica, 10, 69-75. HeATON, K. W. & GmSON, M. J. (1973). The use of 'fatty meals' in oral cholecystography: report of a postal survey in England and Wales. Clinical Radiology, 24, 90-94. HODGES, F. J. & WHITEHOUSE,W. M. (1965). The Gastrointestinal Tract: A Handbook of Roentgen Diagnosis, 2nd ed. Year Book Medical Publishers, Chicago. Hoo~soN, J. R. (1970). The technical aspects of cholecystography. Radiological Clinics of North America, 8 (1), 85-97.
The fatty meal is essential for the diagnosis of adenomyomatosis and cholesterolosis, and m a y occasionally be helpful in revealing small stones. The post-fatty meal films are o f little help in assessing the biliary ducts, or separating the opacifled gallbladder f r o m overlying bowel gas, and are o f no help in diagnosing functional biliary tract disorders. The biliary ducts are more likely to be opacified before the fatty meal in the presence of gallstones.
A. E. (1971). Gallbladder inertia and sluggish enterohepatic circulation of bile salts in coeliac disease. Lancet, 1, 991-994. MARCEl.IS, A. R. & BURHENNE, H. J. (1967) (Editors). Alimentary Tract Roentgenology. Mosby, St Louis. MmLER, R. E., CEml~NISH,S. M. & RODDA, B. E. (1974). Cholecystography: a cost reduction study. Radiology, 110, 61-65. PAUL,L. W. & JUHL,J. H. (1965). The Essentials of Roentgen Interpretation, 2rid edn. Harpter and Row, New York. StrrTON, D. & GRAINGER,R. H. (1969) (Editors). Textbook of Radiology. Livingstone, Edinburgh.
Low-BEER, T. S., HEATON, K. W., HEATON, S. T. ¢~ READ,
