Jun 3, 1985 - ventional uro-angiographic contrast media (diatrizoate and iothalamate) in which opacification of the gallbladder is unusual and strongly ...
1985, The British Journal of Radiology, 58, 511-513
JUNE 1985
Gallbladder visualisation following paediatric cardioangiography with Hexabrix By *J. E. Gillespie, M.B., D.M.R.D., F.R.C.R., *A. Gholkar, M.B., B.S., and S. Gupta, M.B. M.R.C.P., F.R.C.R. Department of Radiology, Royal Manchester Children's Hospital, Pendlebury, Manchester (Received November 1984)
ABSTRACT
Fifty children had an upper abdominal radiograph performed 24 hours after cardioangiography with Hexabrix (meglumine/sodium ioxaglate). The gallbladder was clearly visualised in 32 patients (64%) in the absence of clinical or radiographic evidence of renal impairment. Total contrast dose would appear to be the main determining factor. Hexabrix differs significantly in this respect from conventional uro-angiographic contrast media (diatrizoate and iothalamate) in which opacification of the gallbladder is unusual and strongly associated with renal impairment. Possible reasons for this difference are discussed.
Gallbladder opacification on plain radiographs following intravenous injection of conventional uroangiographic contrast media (diatrizoate and iothalamate) is a well documented but unusual occurrence, generally associated with impaired renal function or unilateral renal obstruction (Becker et al, 1968; Shea & Pfister, 1969; Lautin & Friedman, 1982). Recently, in our department, a child was noted to have gallbladder opacification as a chance finding 24 hours after cardioangiography with the more recently introduced contrast medium Hexabrix (meglumine/sodium ioxaglate). The frequency and significance of this occurrence after Hexabrix injection had not, to our knowledge, been previously reported and its relationship to renal function was speculative. Assessment of renal status is vital in the management of these patients and it was felt that the small additional radiographic exposure was justified when taken in the context of the relatively large radiation dose inevitable during the pre-operative assessment, post-operative recovery and long term follow-up.
The 6- and 24-hour films were reviewed for the presence of contrast medium in the gallbladder or bowel, and for urinary tract abnormalities. These findings were correlated with the patient's weight and dose of contrast medium injected. RESULTS
Contrast medium in gallbladder Thirty-two of the 50 patients (64%) had gallbladder opacification on the 24-h post-angiogram radiograph (Fig. 1.). In none of the patients was contrast medium seen in the gallbladder on the 6-h radiograph (Fig. 2).
METHOD
Fifty consecutive patients (aged 2 months to 15 years) who had undergone cardioangiography with Hexabrix 320 had, in addition to the 6-hour post-angiogram radiograph performed routinely for urinary tract assessment, one further radiograph 24 hours after angiography. This was coned to the right upper abdomen unless a wider area was indicated for other clinical reasons. FIG.
*Present address: Department of Diagnostic Radiology, Stopford Building, Oxford Road, Manchester M13 9PT
1.
Opacified gallbladder seen 24 h after angiography.
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58, No. 690 / . E. Gillespie, A. Gholkar and S. Gupta Urinary tract assessment Apart from one patient with congenital absence of one kidney, all the patients had normal urinary tracts on the 6-h radiographs (Fig. 2). No patient had clinical evidence of renal impairment. Biochemical tests were not routinely performed in patients who, apart from their cardiac abnormality, were otherwise fit and healthy. In those patients in whom such tests were performed, no abnormality of renal function was detected. Dose of Hexabrix The details of the dose of Hexabrix are shown in Table I. Hexabrix dose expressed in ml/kg was not found to be an important factor affecting gallbladder opacification. In fact, those patients without gallbladder or colon opacification received a higher mean dose of contrast medium in ml/kg than those in whom this opacification was present. Weight The weights of the patients are given in Table II. Seven of the 10 patients who did not have contrast medium in the gallbladder or colon weighed less than 10 kg. DISCUSSION
FIG. 2. Same patient as in Fig. 1. Normal renal tract seen 6 h after angiography. No gallbladder opacification is seen.
Contrast medium in bowel Twenty-five patients (50%) had opacification of the colon on the 24-h radiograph. This number is probably an underestimate since much of the colon was not included on the radiographs of many of the patients. In 8 of these 25 patients the colonic contrast medium was seen in the absence of gallbladder opacification. In none of the patients was contrast medium seen in the colon on the 6-h radiograph.
After giving Hexabrix we were able to visualise the gallbladder clearly in 32 of our 50 patients (64%), 49 of whom had normal renal tracts. Segall (1969) on the other hand, using sodium diatrizoate, could find no evidence of gallbladder opacification on the plain films of 101 normal patients taken 24 hours after double dose pyelography and confirmed the general association of this phenomenon with renal dysfunction. The reasons for this difference are not clear and several factors may be involved. One study (Owman & Olin, 1978) on rabbits found that Hexabrix provoked much less choleresis than iothalamate and diatrizoate. They also suggest that elimination of Hexabrix from the blood stream into bile may be an active process, unlike conventional media which were eliminated passively. If
TABLE I HEXABRIX DOSE AND GALLBLADDER OR COLON OPACIFICATION
Dose of Hexabrix Total (ml/patient)
0-24
No. of patients: with contrast medium in gallbladder or colon 3(2) without contrast medium in gallbladder or colon 5 Total 8
25-49
50-74
75-99
Range 100-124 125-140 (ml/kg)
Mean (ml/kg)
15(3)
8(2)
6
6(1)
2
0.7-5.6
2.6
4 19
1 9
0 6
0 6
0 2
1.0-5.8
3.6
The figures in brackets indicate the number of patients with colonic opacification only. 512
JUNE 1985
Gallbladder visualisation with Hexabrix TABLE II WEIGHT DISTRIBUTION OF 50 CHILDREN UNDERGOING CARDIOANGIOGRAPHY WITH HEXABRIX
Weight (kg)
0-10
No. of patients: with contrast medium in gallbladder or colon without contrast medium in gallbladder or colon Total
11-20
8
12
7 15
2 14
the same effect occurs in the human, this would result in a higher concentration of Hexabrix in the gallbladder than a similar injected dose of a conventional contrast medium. We consider protein binding unlikely to be an important factor as the binding percentage of Hexabrix to plasma protein (Mutzel et al, 1980) is similar to that of iothalamate and diatrizoate (Speck et al, 1977). Lautin and Friedman (1982) have pointed out that after injection with diatrizoate or iothalamate, colonic opacification without gallbladder opacification was usually the result of biliary excretion of contrast medium, the gallbladder having emptied and no longer containing enough contrast medium to be visible. This being so, we divided the 50 patients into two groups, those patients with contrast medium in either the gallbladder or colon and those patients with no visible contrast medium in either of these two organs (Table I). Thirty-seven of the 40 patients with gallbladder or colon opacification received over 24 ml of Hexabrix; the remaining three patients received between 20 and 24 ml. Five of the 10 patients with no opacification of either organ received less than 25 ml of Hexabrix; two of the remaining five patients received between 25 and 28 ml. This suggests that a minimum total Hexabrix dose of approximately 25 ml (range 20-28 ml) is required to be injected intravascularly before the gallbladder will be visualised. This variation in contrast dose (20-28 ml) is acceptable since the precise amount of contrast medium required within the gallbladder before it can be visualised depends on several factors including gallbladder size (Janower & Lundstrom, 1980). This leaves three patients who received over 40 ml of Hexabrix who did not have gallbladder or colon opacification for which we have no explanation.
21-30
31-40
41-50
51-60
respect, Hexabrix differs from conventional uroangiographic contrast media. This opacification is doserelated, the minimum required total dose of Hexabrix in our series being about 25 ml. Although our patients were children, we would expect similar results in adults provided that delayed films are performed after a sufficient dose of Hexabrix has been injected intravascularly. ACKNOWLEDGMENTS
We would like to thank Dr. G. H. Watson and Dr. R. G. Patel, Royal Manchester Children's Hospital, for their cooperation during this study, Mrs A. Schofield for typing the manuscript, and Mr. D. Ellard for preparing the illustrations. REFERENCES BECKER, J. A., GREGOIRE, A., BERDON, W. & SCHWARTZ, D.,
1968. Vicarious excretion of urographic media. 90, 243-248.
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JANOWER, M. L. & LUNDSTROM, P., 1980. Biliary
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opacification: effect of iodine concentration and luminal size. American Journal, of Roentgenology, 136, 515-516. LAUTIN, E. M. & FRIEDMAN, A. C , 1982. Vicarious excretion
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MUTZEL, W., SIEFERT, H. & SPECK, U., 1980. Biochemical-
pharmacologic properties of iohexol. Ada Radiologica, Supplementum 362, 111-115. OWMAN, T. & OLIN, T., 1978. Biliary excretion of urographic contrast media. Annales de Radiologie, 21, 309-314. SEGALL, H. D., 1969. Gallbladder visualisation following the injection of diatrizoate. American Journal of Roentgenology, 107, 21-26. SHEA, T. E. & PFISTER, R. C ,
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gallbladder by urographic contrast media. American Journal of Roentgenology, 107, 763-768. SPECK, U., NAGEL, R., LEISTENSCHNEIDER, W. & MUTZEL, W.,
CONCLUSION
Gallbladder opacification on plain radiography performed 24 hours after the intravascular injection of Hexabrix is a common finding of no significance. In this
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1977. Pharmakokinetik und Biotransformation neuer Rontgenkontrastmittel fur die Uro- und Angiographie beim Patienten. Fortschritte auf dem Gebiete der Roentgenstrahlen und der Nuklearmedizin, 127, 270-274.
