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Preoperative Evaluation of the Biliary Tract
Symposium on Surgical Practice at the Lahey Clinic I
Preoperative Evaluation of the Biliary Tract John A. Shea, M.D.*
The discovery of jaundice in a patient may require diagnostic decisions of the physician. The patient who presents with pancreatic or biliary disease or with both conditions often has characteristic clinical symptoms that may make testing unnecessary or, indeed, superfluous. Acute cholecystitis may warrant emergency surgery, and testing may delay treatment to the point of placing the patient at risk. A known pancreatic cancer with jaundice requires few diagnostic tests. Often, however, the clinician can make a probable judgment but would be more comfortable with supportive objective data. At times, a definite diagnosis can be made only with the results of specific tests. This discussion will address the role of diagnostic studies in evaluating the patient presumed to have surgical or obstructive jaundice. Biliary and pancreatic testing has come of age in the past 10 years. Specific studies have made objectively evident what was once a "black box." As recently as 15 years ago, great emphasis was placed on distinguishing medical from surgical jaundice by clinical course and laboratory tests for alkaline phosphatase, serum glutamic oxaloacetic transaminase (SCOT), and bilirubin. Often such judgments were in error. Patients might wait in hospital for 7 to 10 days for clinical determination of the cause of jaundice. Several technical developments may now allow the internist and surgeon to identify the disease and plan a specific approach. Surgical procedures can be directed and exploration limited. Valuable operative time is shortened. The specific tests that are now an integral part of the armamentarium are ultrasound imaging, 1, 11 percutaneous transhepatic cholangiography using the Chiba needle, endoscopic retrograde cholangiopancreatography (ERCP), flexible choledochoscopy, computed tomographic (CT) scan, 8 hepatobiliary iminodiacetic acid (HIDA) scan,3 and intravenous cholangiography.
*Staff,
Department of Gastroenterology, Massachusetts
Lahey Clinic Medical Center,
Surgical Clinics of North America-Vol. 65, No.1, February 1985
Burlington,
47
48
JOHN A. SHEA
ABDOMINAL ULTRASONOGRAPHY Abdominal ultrasound examination has the great advantage of being noninvasive and essentially free from risk. Ultrasound imaging technique may define the presence of gallstones, a dilated biliary tree (Fig. lA), abnormal hepatic anatomy, pancreatic abnormality, unsuspected retroperitoneal disease, and renal disease. An important problem is the presence of gas, which often obscures precise anatomic definition. The patient who presents with acute pain in the right upper abdominal quadrant de novo will often offer only a vague indication of localization, indistinct description, and nonrelated complaints. Definition of calculi within the gallbladder by ultrasound scanning often helps the physician to redirect the questioning of the patient to such favors as radiation of the pain and differentiation from previous ulcer or anginal pain. Occasionally, a patient will present with vague distress in the right upper quadrant of the abdomen and elevated levels of alkaline phosphatase. Ultrasound imaging will define dilated ducts despite the absence of jaundice. Associated intraductal calculi or lesions of the pancreatic head may be sufficient clinical evidence for the surgeon to proceed with specific therapy, such as choledocholithotomy, biliary bypass, or pancreatic resection. Ultrasound scanning is helpful in detecting occult cancer, which may be accompanied by pain in the right upper quadrant of the abdomen and jaundice, since jaundice does not interfere with its interpretation. Metastatic lesions may be defined so readily that a liver biopsy can be directed at a lesion. This may save considerable time in the evaluation of an ill patient in whom the primary malignant disease cannot be found. Ultrasound may also be very useful in defining retroperitoneal adenopathy. Unsuspected lymphoma may cause portal adenopathy and secondary obstructive jaundice. Renal tumors, which may be silent, are occasionally found
Figure 1. A, Ultrasound scan shows dilated common bile duct. B, Operative cholangiogram reveals a calculus in the distal duct.
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
49
to be the cause of abnormal results of liver function tests. Stauffer's syndrome,15 the association of hypernephroma with abnormal liver function, can be a confusing clinical entity since no primary liver disease is, in fact, present. 12, 17 Ultrasound is not a good test for defining calculi in the common bile duct, although they may occasionally be demonstrated (Fig. 2B). Several investigations have reported a poor yield in detecting the presence of calculi. Cronan et a1. 2 studied 87 consecutive patients prospectively to determine the presence or absence of choledocholithiasis before operation. All of these patients had calculi, but they were detected by ultrasound examination in only 13 per cent. Laing and Jeffrey 9 studied 53 patients with calculi in either the common bile duct or the head of the gallbladder. Their detection rate for calculi was approximately 30 per cent. Cronan et al. 2 found that the limiting factor was the presence of a duct of normal caliber, which made definition of any calculus in the duct difficult. Gross et al. 5 prospectively studied 90 patients who were to undergo ERCP, percutaneous transhepatic cholangiography, or surgical intervention and reported that ultrasound had only a 25 per cent sensitivity to the presence of calculi. Dilated ducts may be an indication of choledocholithiasis (see Fig. 1). The safety of ultrasound scanning must be considered when evaluating a patient in whom jaundice develops acutely during pregnancy. Questions concerning potential side effects to the fetus were addressed in a recent meeting of a committee of the National Institutes of Health but have not yet been resolved. The ultimate recommendation is to perform ultrasound
Figure 2. A, Calculus in common bile duct revealed by ERCP. B, Ultrasound scan shows calculus in the same patient.
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SHEA
examination during pregnancy only when absolutely necessary. The rare patient with acute onset of jaundice appears to be one of those instances.
PERCUTANEOUS TRANS HEPATIC CHOLANGIOGRAPHY Percutaneous transhepatic cholangiography of the common bile duct using the Chibil needle has gained increasing acceptance in the last two decades. Percutaneous delineation of the ducts with contrast material is an older technique. The newer application involves a narrow-gauge (No. 23) Chiba needle, which essentially obviates the complication of bile leakage. Infection with septicemia and death is a considerable risk in compromised patients, however. The advantage of this technique to the surgeon is the saving of valuable operative time because disease is localized preoperatively (Figs. 3B, 4B, 5, 6, and 7B). Use of the Chiba needle may allow placement of therapeutic catheters for drainage of the bile before operation. The alleviation of jaundice will substantially decrease the operative morbidity and mortality. Stents may also be placed for internal biliary drainage in the patient whose anatomy will not allow surgical anastomosis, as in the case of high Klatskin tumors (see Fig. 4). The debate about whether to look at the common bile duct from above or below is academic. Endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography are complementary, and the order in which they are performed is usually defined by the experience and expertise of the institution. Percutaneous transhepatic cholangiography can be performed with relative ease in most radiology departments. Dilated ducts are much easier to visualize; the success rate is 95 per cent in one study.7 Approximately 60 per cent of nondilated ducts are visualized. Some investigators 7 report minimal or no difference in success rate, but the number of passes required to visualize nondilated ducts may be quite high.
Figure 3. A, Computed tomographic scan of the liver shows dilated intrahepatic ducts. B, Percutaneous study demonstrates stricture and proximal dilatation of the mid portion of the common bile duct.
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
51
Figure 4. Klatskin tumor. A, Ultrasound scan reveals dilated bile ducts. B, Percutaneous study. Contrast material is seen in proximal dilated ducts; nonfilling of the porta hepatis and filling of the distal duct are obvious through the small opening in the tumor.
ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY
The use of ERCP in the evaluation of the jaundiced patient has many advantages. It allows the physician to assess the stomach and duodenum. If duodenal changes suggest malignant disease, biopsy may be performed. The ampulla of Vater may be assessed critically to rule out ampullary carcinoma, and the pancreatic duct may be cannulated to exclude pancreatic cancer (Fig. 8). The common bile duct can also be observed. If calculi are present (see Fig. 2A), endoscopic papillotomy may be carried out. If cancer is seen, placement of a stent is possible. The risks of ERCP are those of endoscopy in general, plus pancreatitis or sepsis if the common bile duct is obstructed. The overall incidence of complications in endoscopic papillotomy is about 10 per cent.l4 The incidence of serious or life-threatening complications is considerably lower than this, however.
Figure 5. Percutaneous study demonstrates dilatation of the biliary duct down to the area of the pancreas.
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Figure 6. Percutaneous study reveals calculi in the common bile duct after cholecystectomy.
Some physicians advocate preoperative endoscopic papillotomy if calculi are seen in the common bile duct. This allows the surgeon to deal only with the gallbladder at the time of operation. However, endoscopic papillotomy adds the risks of bleeding and retroduodenal perforation. The debate regarding preoperative performance of endoscopic papillotomy is unresolved. The conditions detected by this procedure can, of course, be taken care of operatively. Certain situations may preclude the performance of ERCP. A Billroth II gastroenterostomy reduces the success rate to approximately 50 per cent in even the most experienced hands. Active pancreatitis is a relative contraindication, since inflammation would be considerably aggravated by injection of the pancreatic duct. Endoscopic papillotomy may be performed
Figure 7. Choledochocele seen on CT scan (A) and on percutaneous transhepatic cholangiography (8).
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
53
Figure 8. ERCP study. Double duct sign pancreatic cancer is seen in a 19-yearold man. Concomitant stricturing was seen in both pancreatic and common bile ducts.
if limited strictly to the common bile duct. Each patient must be individually assessed for ERCP. FLEXIBLE CHOLEDOCHOSCOPY Flexible choledochoscopy before repeat operation is an adjunct to the postoperative management of the patient who requires reoperation for some reason. The critically ill patient who cannot tolerate exploration of the common bile duct and is said to have calculi may have simple cholecystectomy and placement of a T tube. The tract is allowed to mature for four to six weeks and may then be used for placement of a flberoptic instrument with which calculi can be extracted. The T tube is removed, and the tract is used as a conduit for the choledochoscope. Direct visualization is usually easier proximally because of the angle of the T -tube tract. Calculi seen proximally can be retrieved, and suspicious areas can be biopsied. The distal area above the sphincter may also be inspected and calculi removed. The sphincteric area may be difficult or impossible to penetrate because of muscular contraction. Contrast material can be passed by means of a red rubber catheter for inspection of this area after choledochoscopy. Unretrieved calculi can be removed surgically or even with endoscopic papillotomy, if indicated. The risks of flexible choledochoscopy include
54
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SHEA
sepsis and perforation of the tract into the peritoneum. Strictures in the ductal system may prevent retrieval of calculi.
COMPUTED TOMOGRAPHY Computed tomography has been enjoying great popularity recently. It is used widely and sometimes appropriately. Obstructive jaundice is, in general, an appropriate indication. The patient who presents with jaundice is often a "black box." Clinical clues can be detected, however. The patient with jaundice, dark urine, chills, fever, and pain in the right upper quadrant of the abdomen will usually have cholangitis secondary to choledocholithiasis. The elderly patient who has "naked" (asymptomatic) jaundice, periumbilical pain radiating to the back, nighttime awakening, and weight loss will often but not always have pancreatic cancer. Computed tomographic scan is the first step in an algorithm that leads to differentiation of cause. 4 The scan is important because it will delineate dilated ducts (see Fig. 3A). In addition, lesions in the pancreatic head, metastatic hepatic lesions, retroperitoneal adenopathy, and gastric lesions can be defined by CT scan (Figs. 7A and 9).
HEPATOBILIARY IMINODIACETIC ACID SCAN Within the past five years, the HIDA scan has become an important method for identifying the cause of right upper quadrant abdominal pain. Biliary excretion is the normal route for lipid-soluble compounds. Organic ions with a molecular weight greater than 300 are excreted this way because the kidney cannot process them efficiently. Derivatives of iminodiacetic acid are important because they can be chelated with technetium 99m to form a dimer with a higher molecular weight. This molecule can be substituted with side chains to increase its lipid solubility. These agents are extracted by the liver from both hepatic arterial and portal venous blood. They are actively transported across the hepatocytes, bound to intracellular proteins, and secreted into the biliary canaliculi. They travel into the main bile ducts, gallbladder, and duodenum. Excretion may be diminished by decreased liver flow, congenitally abnormal liver function, deficiency of conjugation, and toxic or infectious changes in the liver. Obstruction to outflow may also influence excretion. With biliary obstruction, the production and excretion of these agents will be stopped. The most important application of derivatives of iminodiacetic acid is in the area of suspected obstruction and bile stasis. They are also used in studying gallbladder function and intestinal transit of bile. Imaging of the liver is an added feature that may also be helpful. If the cystic duct is patent, the gallbladder should fill with contrast material; 99mTc-butyl-iminodiacetic acid is injected intravenously while the patient is in the supine position. The camera is centered so that the whole liver may be viewed. Hepatic activity of this agent is at its peak approximately 12 to 15 minutes after injection. The common bile duct and the intestine are visible in about
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
55
Figure 9. A, CT scan shows cancer of the common bile duct with an incidental renal cyst on the left. B, CT scan demonstrates dilated biliary system with upper gastrointestinal extension of abnormality into the periduodenal area and pressure on the antrum and duodenum. C, Upper gastrointestinal barium study shows antral deformity.
20 minutes, and the gallbladder is visible between 20 and 40 minutes after injection. Serial films are taken at 5-minute intervals for a total of 60 minutes. If biliary patency is being tested and no activity is seen in the intestine after an hour, follow-up studies are performed every hour for 6 hours and again at 24 hours. Demonstration of a patent biliary tree is closely correlated with the absence of obstruction. However, slow elimination of the injected tracer, which may be visible only after 24 hours, may be compatible with intrahepatic cholestasis. Partial obstruction may not be detected by this test since the tracer can get by it. An obstructed cystic duct and acute biliary colic will prevent the gallbladder from filling, indicating acute cholecystitis. Dilated ducts, also an indication of biliary obstruction, can be seen by HIDA scan, but real-time ultrasonography is probably more useful for distinguishing dilated ducts from nondilated ducts. Abnor-
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SHEA
mal results of HIDA scan may be difficult to interpret if any of the preconditions for the test, such as poor liver function, are not met. INTRAVENOUS CHOLANGIOGRAPHY Intravenous cholangiography, though in some disfavor, is occasionally appropriate for evaluation of the biliary tract (Fig. 10), but an increase in bilirubin level to greater than 3 mg per dl essentially eliminates the test as a useful maneuver, since visualization is not possible above that level. If the bilirubin level decreases, some visualization of the biliary system may be possible, but it is often imperfect and interpretation is quite difficult. Goodman et al. 4 have said that intravenous cholangiography should no longer be performed. This statement is overly strong but basically true. Endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography offer much better anatomic definition and fewer false-positive and false-negative results. Allergic reactions are always a concern with intravenous cholangiography. Occasionally, the question of biliary disease arises in a patient with Billroth II anastomosis. In such instances, intravenous cholangiography of good quality may obviate the need for percutaneous study.
ALGORITHMIC APPROACH TO TESTING Numerous techniques are now available for evaluation of the patient who presents with what clinically appears to be obstructive jaundice. The most important part of this algorithmic approach to testing is the clinical acumen and judgment of the investigator. Given that, the physician can direct the studies so that a diagnosis may be made in an efficient manner.
Figure 10. shows calculi.
Intravenous cholangiogram
57
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
Vennes and Bond16 addressed the problem of the selection of tests. Matzen et al. 10 and O'Connor et a1. 13 reviewed and compared the sensitivity and specificity of different diagnostic techniques. Matzen et al.lo recommended ultrasound examination with a dynamic scanner as the noninvasive imaging procedure of choice in jaundiced patients with suspected obstruction of the common bile duct. Computed tomography was seen as a possible but somewhat limited alternative because of its high cost. They did not recommend HIDA scan for distinguishing between obstructive and hepatic jaundice. O'Connor et al.l3 advised that a thorough clinical evaluation be followed by ultrasonography or CT scan because these tests are noninvasive and specific. If clinical evaluation and ultrasound or CT scan point toward intrahepatic cholestasis, liver biopsy is performed. If the indication is that the obstruction is extrahepatic, more precise definition is obtained by either ERCP or percutaneous transhepatic cholangiography. The algorithm (Fig. 11) presented by O'Connor et al,l3 is a useful outline. Heiss et al. 6 have presented a therapeutic algorithm that is helpful if a calculus is found.
CE
us
IF BOTH TESTS AGREE:
, '" /
INTRAHEPATIC
EXTRAHEPATIC
NEEDLE BIOPSY
ERCP or PTC (OPTIONAL)
~
1
and/or CT
IF TESTS DISAGREE:
1
ERCP or PTC ± NEEDLE BIOPSY
~
SURGERY
Figure 11. AlgOrithm for study of the jaundiced patient combines clinical evaluation with noninvasive and invasive tests. PrC = percutaneous transhepatic cholangiography. (From O'Connor, K. W., et al.: A blinded prospective study comparing four current noninvasive approaches in the differential diagnosis of medical versus surgical jaundice. Gastroenterology, 84:1503, 1983, with permission.)
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JOHN A. SHEA
SUMMARY When clinically suspected, obstructive jaundice presents the clinician with the problem of selecting the most suitable tests and determining the order in which they should be performed. Technology has provided a number of highly specific and quite expensive procedures. The studies most appropriately performed are ultrasonography, percutaneous transhepatic cholangiography, ERCP, flexible choledochoscopy, CT scan of the abdomen, HIDA scan, and intravenous cholangiography. The algorithmic approach is clinically helpful in this situation and is recommended as a useful guide. REFERENCES 1. Cooperberg, P., and Golding, R. H: Advances in ultrasonography of the gallbladder and biliary tract. Radiol. Clin. North Am., 20:611-633, 1982. 2. Cronan, J. J., Mueller, P. R., Simeone, J. F., et al.: Prospective diagnosis of choledocholithiasis. Radiology, 146:467-469, 1983. 3. Davies, E. R.: Radionuclide investigations. Clin. Gastroenterol., 13:205-233, 1984. 4. Goodman, M. W., Ansel, H. J., Vennes, J. A., et al.: Is intravenous cholangiography still useful? Gastroenterology, 79:642-645, 1980. 5. Gross, B. H., Harter, L. P., Gore, R. M., et al.: Ultrasonic evaluation of common bile duct stones: Prospective comparison with endoscopic retrograde cholangiopancreatography. Radiology, 146:471-474, 1983. 6. Heiss, F. W., Rossi, R. L., Scholz, F. J., et al.: Common bile duct calculi. 1. Surgical therapy. 2. Nonsurgical therapy. Postgrad. Med., 75:88-94, 99-104, 109-117, 1984. 7. Jacques, P. F., Mauro, M. A., and Scatliff, J. H.: The failed transhepatic cholangiogram. Radiology, 134:3:J-35, 1980. 8. Kreel, L.: Computed tomography in gastroenterology. Clin. Gastroenterol., 13:235-264, 1984. 9. Laing, F. C., and Jeffrey, R. B., Jr.: Choledocholithiasis and cystic duct obstruction: Difficult ultrasonographic diagnosis. Radiology, 146:475-479, 1983. 10. Matzen, P., Malchow-Moller, A., Brun, B., et al.: Ultrasonography, computed tomography, and cholescintigraphy in suspected obstructive jaundice-a prospective comparative study. Gastroenterology, 84:1492-1497, 1983. 11. Meire, H. B.: Ultrasound in gastroenterology. Clin. Gastroenterol., 13:183-203, 1984. 12. Mohamed, S. D.: Reversible non-metastatic liver-cell dysfunction and thrombocytosis from a hypernephroma. Lancet, 2:621-623, 1965. 13. O'Connor, K. W., Snodgrass, P. J., Swonder, J. E., et al.: A blinded prospective study comparing four current noninvasive approaches in the differential diagnosis of medical versus surgical jaundice. Gastroenterology, 84:1498-1504, 1983. 14. Safrany, L.: Endoscopic treatment of biliary-tract diseases: An international study. Lancet, 2:983-985, 1978. 15. Stauffer, M. H.: Nephrogenic hepatosplenomegaly. (Abstract.) Gastroenterology, 40:694, 1961. 16. Vennes, J. A., and Bond, J. H.: Approach to the jaundiced patient. (EditoriaL) Gastroenterology, 84:1615-1618, 1983. 17. Walsh, P. N., and Kissane, J. M.: Nonmetastatic hypernephroma with reversible hepatic dysfunction. Arch. Intern. Med., 122:214-222, 1968.
Department of Gastroenterology Lahey Clinic Medical Center 41 Mall Road Box 541 Burlington, Massachusetts 01805
Preoperative Evaluation of the Biliary Tract John A. Shea, M.D.*
The discovery of jaundice in a patient may require diagnostic decisions of the physician. The patient who presents with pancreatic or biliary disease or with both conditions often has characteristic clinical symptoms that may make testing unnecessary or, indeed, superfluous. Acute cholecystitis may warrant emergency surgery, and testing may delay treatment to the point of placing the patient at risk. A known pancreatic cancer with jaundice requires few diagnostic tests. Often, however, the clinician can make a probable judgment but would be more comfortable with supportive objective data. At times, a definite diagnosis can be made only with the results of specific tests. This discussion will address the role of diagnostic studies in evaluating the patient presumed to have surgical or obstructive jaundice. Biliary and pancreatic testing has come of age in the past 10 years. Specific studies have made objectively evident what was once a "black box." As recently as 15 years ago, great emphasis was placed on distinguishing medical from surgical jaundice by clinical course and laboratory tests for alkaline phosphatase, serum glutamic oxaloacetic transaminase (SCOT), and bilirubin. Often such judgments were in error. Patients might wait in hospital for 7 to 10 days for clinical determination of the cause of jaundice. Several technical developments may now allow the internist and surgeon to identify the disease and plan a specific approach. Surgical procedures can be directed and exploration limited. Valuable operative time is shortened. The specific tests that are now an integral part of the armamentarium are ultrasound imaging, 1, 11 percutaneous transhepatic cholangiography using the Chiba needle, endoscopic retrograde cholangiopancreatography (ERCP), flexible choledochoscopy, computed tomographic (CT) scan, 8 hepatobiliary iminodiacetic acid (HIDA) scan,3 and intravenous cholangiography.
*Staff,
Department of Gastroenterology, Massachusetts
Lahey Clinic Medical Center,
Surgical Clinics of North America-Vol. 65, No.1, February 1985
Burlington,
47
48
JOHN A. SHEA
ABDOMINAL ULTRASONOGRAPHY Abdominal ultrasound examination has the great advantage of being noninvasive and essentially free from risk. Ultrasound imaging technique may define the presence of gallstones, a dilated biliary tree (Fig. lA), abnormal hepatic anatomy, pancreatic abnormality, unsuspected retroperitoneal disease, and renal disease. An important problem is the presence of gas, which often obscures precise anatomic definition. The patient who presents with acute pain in the right upper abdominal quadrant de novo will often offer only a vague indication of localization, indistinct description, and nonrelated complaints. Definition of calculi within the gallbladder by ultrasound scanning often helps the physician to redirect the questioning of the patient to such favors as radiation of the pain and differentiation from previous ulcer or anginal pain. Occasionally, a patient will present with vague distress in the right upper quadrant of the abdomen and elevated levels of alkaline phosphatase. Ultrasound imaging will define dilated ducts despite the absence of jaundice. Associated intraductal calculi or lesions of the pancreatic head may be sufficient clinical evidence for the surgeon to proceed with specific therapy, such as choledocholithotomy, biliary bypass, or pancreatic resection. Ultrasound scanning is helpful in detecting occult cancer, which may be accompanied by pain in the right upper quadrant of the abdomen and jaundice, since jaundice does not interfere with its interpretation. Metastatic lesions may be defined so readily that a liver biopsy can be directed at a lesion. This may save considerable time in the evaluation of an ill patient in whom the primary malignant disease cannot be found. Ultrasound may also be very useful in defining retroperitoneal adenopathy. Unsuspected lymphoma may cause portal adenopathy and secondary obstructive jaundice. Renal tumors, which may be silent, are occasionally found
Figure 1. A, Ultrasound scan shows dilated common bile duct. B, Operative cholangiogram reveals a calculus in the distal duct.
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
49
to be the cause of abnormal results of liver function tests. Stauffer's syndrome,15 the association of hypernephroma with abnormal liver function, can be a confusing clinical entity since no primary liver disease is, in fact, present. 12, 17 Ultrasound is not a good test for defining calculi in the common bile duct, although they may occasionally be demonstrated (Fig. 2B). Several investigations have reported a poor yield in detecting the presence of calculi. Cronan et a1. 2 studied 87 consecutive patients prospectively to determine the presence or absence of choledocholithiasis before operation. All of these patients had calculi, but they were detected by ultrasound examination in only 13 per cent. Laing and Jeffrey 9 studied 53 patients with calculi in either the common bile duct or the head of the gallbladder. Their detection rate for calculi was approximately 30 per cent. Cronan et al. 2 found that the limiting factor was the presence of a duct of normal caliber, which made definition of any calculus in the duct difficult. Gross et al. 5 prospectively studied 90 patients who were to undergo ERCP, percutaneous transhepatic cholangiography, or surgical intervention and reported that ultrasound had only a 25 per cent sensitivity to the presence of calculi. Dilated ducts may be an indication of choledocholithiasis (see Fig. 1). The safety of ultrasound scanning must be considered when evaluating a patient in whom jaundice develops acutely during pregnancy. Questions concerning potential side effects to the fetus were addressed in a recent meeting of a committee of the National Institutes of Health but have not yet been resolved. The ultimate recommendation is to perform ultrasound
Figure 2. A, Calculus in common bile duct revealed by ERCP. B, Ultrasound scan shows calculus in the same patient.
50
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SHEA
examination during pregnancy only when absolutely necessary. The rare patient with acute onset of jaundice appears to be one of those instances.
PERCUTANEOUS TRANS HEPATIC CHOLANGIOGRAPHY Percutaneous transhepatic cholangiography of the common bile duct using the Chibil needle has gained increasing acceptance in the last two decades. Percutaneous delineation of the ducts with contrast material is an older technique. The newer application involves a narrow-gauge (No. 23) Chiba needle, which essentially obviates the complication of bile leakage. Infection with septicemia and death is a considerable risk in compromised patients, however. The advantage of this technique to the surgeon is the saving of valuable operative time because disease is localized preoperatively (Figs. 3B, 4B, 5, 6, and 7B). Use of the Chiba needle may allow placement of therapeutic catheters for drainage of the bile before operation. The alleviation of jaundice will substantially decrease the operative morbidity and mortality. Stents may also be placed for internal biliary drainage in the patient whose anatomy will not allow surgical anastomosis, as in the case of high Klatskin tumors (see Fig. 4). The debate about whether to look at the common bile duct from above or below is academic. Endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography are complementary, and the order in which they are performed is usually defined by the experience and expertise of the institution. Percutaneous transhepatic cholangiography can be performed with relative ease in most radiology departments. Dilated ducts are much easier to visualize; the success rate is 95 per cent in one study.7 Approximately 60 per cent of nondilated ducts are visualized. Some investigators 7 report minimal or no difference in success rate, but the number of passes required to visualize nondilated ducts may be quite high.
Figure 3. A, Computed tomographic scan of the liver shows dilated intrahepatic ducts. B, Percutaneous study demonstrates stricture and proximal dilatation of the mid portion of the common bile duct.
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
51
Figure 4. Klatskin tumor. A, Ultrasound scan reveals dilated bile ducts. B, Percutaneous study. Contrast material is seen in proximal dilated ducts; nonfilling of the porta hepatis and filling of the distal duct are obvious through the small opening in the tumor.
ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY
The use of ERCP in the evaluation of the jaundiced patient has many advantages. It allows the physician to assess the stomach and duodenum. If duodenal changes suggest malignant disease, biopsy may be performed. The ampulla of Vater may be assessed critically to rule out ampullary carcinoma, and the pancreatic duct may be cannulated to exclude pancreatic cancer (Fig. 8). The common bile duct can also be observed. If calculi are present (see Fig. 2A), endoscopic papillotomy may be carried out. If cancer is seen, placement of a stent is possible. The risks of ERCP are those of endoscopy in general, plus pancreatitis or sepsis if the common bile duct is obstructed. The overall incidence of complications in endoscopic papillotomy is about 10 per cent.l4 The incidence of serious or life-threatening complications is considerably lower than this, however.
Figure 5. Percutaneous study demonstrates dilatation of the biliary duct down to the area of the pancreas.
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JOHN
A. SHEA
Figure 6. Percutaneous study reveals calculi in the common bile duct after cholecystectomy.
Some physicians advocate preoperative endoscopic papillotomy if calculi are seen in the common bile duct. This allows the surgeon to deal only with the gallbladder at the time of operation. However, endoscopic papillotomy adds the risks of bleeding and retroduodenal perforation. The debate regarding preoperative performance of endoscopic papillotomy is unresolved. The conditions detected by this procedure can, of course, be taken care of operatively. Certain situations may preclude the performance of ERCP. A Billroth II gastroenterostomy reduces the success rate to approximately 50 per cent in even the most experienced hands. Active pancreatitis is a relative contraindication, since inflammation would be considerably aggravated by injection of the pancreatic duct. Endoscopic papillotomy may be performed
Figure 7. Choledochocele seen on CT scan (A) and on percutaneous transhepatic cholangiography (8).
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
53
Figure 8. ERCP study. Double duct sign pancreatic cancer is seen in a 19-yearold man. Concomitant stricturing was seen in both pancreatic and common bile ducts.
if limited strictly to the common bile duct. Each patient must be individually assessed for ERCP. FLEXIBLE CHOLEDOCHOSCOPY Flexible choledochoscopy before repeat operation is an adjunct to the postoperative management of the patient who requires reoperation for some reason. The critically ill patient who cannot tolerate exploration of the common bile duct and is said to have calculi may have simple cholecystectomy and placement of a T tube. The tract is allowed to mature for four to six weeks and may then be used for placement of a flberoptic instrument with which calculi can be extracted. The T tube is removed, and the tract is used as a conduit for the choledochoscope. Direct visualization is usually easier proximally because of the angle of the T -tube tract. Calculi seen proximally can be retrieved, and suspicious areas can be biopsied. The distal area above the sphincter may also be inspected and calculi removed. The sphincteric area may be difficult or impossible to penetrate because of muscular contraction. Contrast material can be passed by means of a red rubber catheter for inspection of this area after choledochoscopy. Unretrieved calculi can be removed surgically or even with endoscopic papillotomy, if indicated. The risks of flexible choledochoscopy include
54
JOHN
A.
SHEA
sepsis and perforation of the tract into the peritoneum. Strictures in the ductal system may prevent retrieval of calculi.
COMPUTED TOMOGRAPHY Computed tomography has been enjoying great popularity recently. It is used widely and sometimes appropriately. Obstructive jaundice is, in general, an appropriate indication. The patient who presents with jaundice is often a "black box." Clinical clues can be detected, however. The patient with jaundice, dark urine, chills, fever, and pain in the right upper quadrant of the abdomen will usually have cholangitis secondary to choledocholithiasis. The elderly patient who has "naked" (asymptomatic) jaundice, periumbilical pain radiating to the back, nighttime awakening, and weight loss will often but not always have pancreatic cancer. Computed tomographic scan is the first step in an algorithm that leads to differentiation of cause. 4 The scan is important because it will delineate dilated ducts (see Fig. 3A). In addition, lesions in the pancreatic head, metastatic hepatic lesions, retroperitoneal adenopathy, and gastric lesions can be defined by CT scan (Figs. 7A and 9).
HEPATOBILIARY IMINODIACETIC ACID SCAN Within the past five years, the HIDA scan has become an important method for identifying the cause of right upper quadrant abdominal pain. Biliary excretion is the normal route for lipid-soluble compounds. Organic ions with a molecular weight greater than 300 are excreted this way because the kidney cannot process them efficiently. Derivatives of iminodiacetic acid are important because they can be chelated with technetium 99m to form a dimer with a higher molecular weight. This molecule can be substituted with side chains to increase its lipid solubility. These agents are extracted by the liver from both hepatic arterial and portal venous blood. They are actively transported across the hepatocytes, bound to intracellular proteins, and secreted into the biliary canaliculi. They travel into the main bile ducts, gallbladder, and duodenum. Excretion may be diminished by decreased liver flow, congenitally abnormal liver function, deficiency of conjugation, and toxic or infectious changes in the liver. Obstruction to outflow may also influence excretion. With biliary obstruction, the production and excretion of these agents will be stopped. The most important application of derivatives of iminodiacetic acid is in the area of suspected obstruction and bile stasis. They are also used in studying gallbladder function and intestinal transit of bile. Imaging of the liver is an added feature that may also be helpful. If the cystic duct is patent, the gallbladder should fill with contrast material; 99mTc-butyl-iminodiacetic acid is injected intravenously while the patient is in the supine position. The camera is centered so that the whole liver may be viewed. Hepatic activity of this agent is at its peak approximately 12 to 15 minutes after injection. The common bile duct and the intestine are visible in about
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
55
Figure 9. A, CT scan shows cancer of the common bile duct with an incidental renal cyst on the left. B, CT scan demonstrates dilated biliary system with upper gastrointestinal extension of abnormality into the periduodenal area and pressure on the antrum and duodenum. C, Upper gastrointestinal barium study shows antral deformity.
20 minutes, and the gallbladder is visible between 20 and 40 minutes after injection. Serial films are taken at 5-minute intervals for a total of 60 minutes. If biliary patency is being tested and no activity is seen in the intestine after an hour, follow-up studies are performed every hour for 6 hours and again at 24 hours. Demonstration of a patent biliary tree is closely correlated with the absence of obstruction. However, slow elimination of the injected tracer, which may be visible only after 24 hours, may be compatible with intrahepatic cholestasis. Partial obstruction may not be detected by this test since the tracer can get by it. An obstructed cystic duct and acute biliary colic will prevent the gallbladder from filling, indicating acute cholecystitis. Dilated ducts, also an indication of biliary obstruction, can be seen by HIDA scan, but real-time ultrasonography is probably more useful for distinguishing dilated ducts from nondilated ducts. Abnor-
56
JOHN
A.
SHEA
mal results of HIDA scan may be difficult to interpret if any of the preconditions for the test, such as poor liver function, are not met. INTRAVENOUS CHOLANGIOGRAPHY Intravenous cholangiography, though in some disfavor, is occasionally appropriate for evaluation of the biliary tract (Fig. 10), but an increase in bilirubin level to greater than 3 mg per dl essentially eliminates the test as a useful maneuver, since visualization is not possible above that level. If the bilirubin level decreases, some visualization of the biliary system may be possible, but it is often imperfect and interpretation is quite difficult. Goodman et al. 4 have said that intravenous cholangiography should no longer be performed. This statement is overly strong but basically true. Endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography offer much better anatomic definition and fewer false-positive and false-negative results. Allergic reactions are always a concern with intravenous cholangiography. Occasionally, the question of biliary disease arises in a patient with Billroth II anastomosis. In such instances, intravenous cholangiography of good quality may obviate the need for percutaneous study.
ALGORITHMIC APPROACH TO TESTING Numerous techniques are now available for evaluation of the patient who presents with what clinically appears to be obstructive jaundice. The most important part of this algorithmic approach to testing is the clinical acumen and judgment of the investigator. Given that, the physician can direct the studies so that a diagnosis may be made in an efficient manner.
Figure 10. shows calculi.
Intravenous cholangiogram
57
PREOPERATIVE EVALUATION OF THE BILIARY TRACT
Vennes and Bond16 addressed the problem of the selection of tests. Matzen et al. 10 and O'Connor et a1. 13 reviewed and compared the sensitivity and specificity of different diagnostic techniques. Matzen et al.lo recommended ultrasound examination with a dynamic scanner as the noninvasive imaging procedure of choice in jaundiced patients with suspected obstruction of the common bile duct. Computed tomography was seen as a possible but somewhat limited alternative because of its high cost. They did not recommend HIDA scan for distinguishing between obstructive and hepatic jaundice. O'Connor et al.l3 advised that a thorough clinical evaluation be followed by ultrasonography or CT scan because these tests are noninvasive and specific. If clinical evaluation and ultrasound or CT scan point toward intrahepatic cholestasis, liver biopsy is performed. If the indication is that the obstruction is extrahepatic, more precise definition is obtained by either ERCP or percutaneous transhepatic cholangiography. The algorithm (Fig. 11) presented by O'Connor et al,l3 is a useful outline. Heiss et al. 6 have presented a therapeutic algorithm that is helpful if a calculus is found.
CE
us
IF BOTH TESTS AGREE:
, '" /
INTRAHEPATIC
EXTRAHEPATIC
NEEDLE BIOPSY
ERCP or PTC (OPTIONAL)
~
1
and/or CT
IF TESTS DISAGREE:
1
ERCP or PTC ± NEEDLE BIOPSY
~
SURGERY
Figure 11. AlgOrithm for study of the jaundiced patient combines clinical evaluation with noninvasive and invasive tests. PrC = percutaneous transhepatic cholangiography. (From O'Connor, K. W., et al.: A blinded prospective study comparing four current noninvasive approaches in the differential diagnosis of medical versus surgical jaundice. Gastroenterology, 84:1503, 1983, with permission.)
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JOHN A. SHEA
SUMMARY When clinically suspected, obstructive jaundice presents the clinician with the problem of selecting the most suitable tests and determining the order in which they should be performed. Technology has provided a number of highly specific and quite expensive procedures. The studies most appropriately performed are ultrasonography, percutaneous transhepatic cholangiography, ERCP, flexible choledochoscopy, CT scan of the abdomen, HIDA scan, and intravenous cholangiography. The algorithmic approach is clinically helpful in this situation and is recommended as a useful guide. REFERENCES 1. Cooperberg, P., and Golding, R. H: Advances in ultrasonography of the gallbladder and biliary tract. Radiol. Clin. North Am., 20:611-633, 1982. 2. Cronan, J. J., Mueller, P. R., Simeone, J. F., et al.: Prospective diagnosis of choledocholithiasis. Radiology, 146:467-469, 1983. 3. Davies, E. R.: Radionuclide investigations. Clin. Gastroenterol., 13:205-233, 1984. 4. Goodman, M. W., Ansel, H. J., Vennes, J. A., et al.: Is intravenous cholangiography still useful? Gastroenterology, 79:642-645, 1980. 5. Gross, B. H., Harter, L. P., Gore, R. M., et al.: Ultrasonic evaluation of common bile duct stones: Prospective comparison with endoscopic retrograde cholangiopancreatography. Radiology, 146:471-474, 1983. 6. Heiss, F. W., Rossi, R. L., Scholz, F. J., et al.: Common bile duct calculi. 1. Surgical therapy. 2. Nonsurgical therapy. Postgrad. Med., 75:88-94, 99-104, 109-117, 1984. 7. Jacques, P. F., Mauro, M. A., and Scatliff, J. H.: The failed transhepatic cholangiogram. Radiology, 134:3:J-35, 1980. 8. Kreel, L.: Computed tomography in gastroenterology. Clin. Gastroenterol., 13:235-264, 1984. 9. Laing, F. C., and Jeffrey, R. B., Jr.: Choledocholithiasis and cystic duct obstruction: Difficult ultrasonographic diagnosis. Radiology, 146:475-479, 1983. 10. Matzen, P., Malchow-Moller, A., Brun, B., et al.: Ultrasonography, computed tomography, and cholescintigraphy in suspected obstructive jaundice-a prospective comparative study. Gastroenterology, 84:1492-1497, 1983. 11. Meire, H. B.: Ultrasound in gastroenterology. Clin. Gastroenterol., 13:183-203, 1984. 12. Mohamed, S. D.: Reversible non-metastatic liver-cell dysfunction and thrombocytosis from a hypernephroma. Lancet, 2:621-623, 1965. 13. O'Connor, K. W., Snodgrass, P. J., Swonder, J. E., et al.: A blinded prospective study comparing four current noninvasive approaches in the differential diagnosis of medical versus surgical jaundice. Gastroenterology, 84:1498-1504, 1983. 14. Safrany, L.: Endoscopic treatment of biliary-tract diseases: An international study. Lancet, 2:983-985, 1978. 15. Stauffer, M. H.: Nephrogenic hepatosplenomegaly. (Abstract.) Gastroenterology, 40:694, 1961. 16. Vennes, J. A., and Bond, J. H.: Approach to the jaundiced patient. (EditoriaL) Gastroenterology, 84:1615-1618, 1983. 17. Walsh, P. N., and Kissane, J. M.: Nonmetastatic hypernephroma with reversible hepatic dysfunction. Arch. Intern. Med., 122:214-222, 1968.
Department of Gastroenterology Lahey Clinic Medical Center 41 Mall Road Box 541 Burlington, Massachusetts 01805