146/40, and a respiratory rate of 18. The rest of herphysical' exam was essentially benign with the followingfindings: anicteric sclera; Grade Il/VI nonradiating systolic murmur, which was loudest at the left sternalborder, lungs were clear to auscultation and percussion;and a nearly normal abdominal exam with only minimal tenderness in the epigastric area and no evidenceof organomegaly or abdominal masses. There were nosigns of peripheral edema or other stigmata of congestive heart failure. On rectal exam, the patient's stoolwas brown and trace heme-positive.

Laboratory assessment was notable for a BUN of 30mg/dl, a total bilirubin of 3.0 mg/cM,and a CBC revealed a hemoglobin level of 7.3 gm/dl with a whiteblood cell count of 11.6 thousand/@il. EKG demonstrated a normal rate and rhythm with left ventricularhypertrophy by voltage and nonspecific ST-T-wavechanges but normal intervals and a normal axis. Chestx-ray was unremarkable except for mild cardiomegaly.

Due to her pain and cardiac history, she was admittedto rule out a myocardial infarction as well as to evaluateher anemia.

Over the following days, cardiac isoenzymes wereobtained and her anemia was treated with blood transfusions, however, the exact source ofthe gastrointestinalbleeding remained unclear. Two days after admission,it was noted that she was becoming jaundiced. Liverfunction tests performed at that time demonstrated analkaline phosphatase ofSS7 LU/i (normal <200) as wellas moderately elevated liver transaminases (AST = 100IU/l, ALT = 1 10 lU/l), and a markedly elevated total

bilirubin of 11.7 mg/dl with a direct bilirubin of 7.6mg/dl. Her white blood cell count also was rising andwas measured at 14.3 thousand/id with a left shift. Shealso developed a fever of 101.6 orally. These findingsuggested obstructive jaundice and possibly cholangitis.Blood cultures were performed and the patient wasstarted on ampidillin and gentamicin empirically (thesecultures eventually demonstrated no growth). A hepatobiliary study was ordered and performed to evaluate

J NucIMed 1991;32:1261-1265

CASE PRESENTATION

An 87-yr-old female presented with a chief complaintofsevere epigastric pain. The pain had started 1.50 daysearlier and lasted all day and part ofthe night. The painwas characterized as burning and radiating to her chest.She denied any radiation to her neck or arms and deniedany dyspnea, although she did have some diaphoresisassociated with the pain. The discomfort was sometimesrelated to eating and often was associated with belching.She had experienced two episodes of nausea and vomiting on the day prior to admission. She had beenexperiencing mild rectal bleeding for several monthswhich had been attributed to hemorrhoids, and forwhich she had been taking iron supplements.

Her past medical history was significant for a myocardial infarction 13 yr earlier, as well as hypertension.Her past history was also significant for diverticulosiswhich was discovered by barium enema 11 yr earlier.Her surgical history was significant for a hysterectomymany years earlier. In addition, she had a 20-pack yearsmoking history, although she stopped smoking 13years prior to admission. She also admitted to moderatealcohol consumption. The family history and review ofsystems were noncontributory.

The patient's medications at home included propranolol for hypertension, procainamide for occasional arrythmias, dicyclomine for bowel spasticity, and ferroussulfate for anemia.

Upon examination, the patient appeared thin butwell developed and in no significant distress. Her temperature was 97.8 orally, pulse 60 bpm, blood pressure

RecO@edMar. 8, 1991; revIsionaccepted Mar. 8, 1991.For reptints contact: Abass Alavi,MD,Departmentof Radiology,DMsion

of Nuclear Medicine, Hospital of the University of PA, 3400 Spruce St. Philadeiphia, PA 19104.)

1261CommonBileDuctStones•SilfenandLong

The Role of Hepatobiliary Imaging in theEvaluation and Management of Patientswith Common Bile Duct GallstonesCase Presentation: Douglas SilfenDiscussion: William B. LongGuest Editor: Abass Alavi

From the Case Records ofThe Hospital of The University of Pennsylvania

biliary drainage. The scan, performed with @mTc@diisopropylimino diacetic acid (DISIDA), demonstratedfairly good uptake oftracer into the liver, but there wasno significant excretion into either the gallbladder, thecommon bile duct or the bowel. This did not changeon delayed images obtained up to 4 hours after injection(Fig. 1). There was also a defect in the porta hepatissuggestive of a dilated common bile duct. The studywas read as very suggestive of high-grade common bileduct obstruction. Next, an ultrasound was performedwhich demonstrated cholelithiasis and “sludge―in thegallbladder as well as a dilated common bile duct butnormal intrahepatic ducts (Fig. 2). At this point, although it appeared that she would be ruled out for amyocardial infarction, her CPK-MB fractions were borderline and it was felt that she may have had somemyocardial damage. Because the patient was thoughtto be at high risk for surgery, an endoscopic retrogradecholangiopancreatography (ERCP) was performed toevaluate the source of possible upper gastrointestinalbleeding as well for treatment of what appeared to beobstructive jaundice due to choledocholithiasis.

ERCP revealed no gastric lesions and showed thatthe duodenum was also normal except for some periampullary diverticuli. The pancreatic duct was normal, butthe common bile duct was moderately dilated and a 1-cm stone was noted high in the common duct (Fig. 3).Attempts at retrieving the stone in a basket were unsuccessful, so a 1.2-cm sphincterotomy was performed toallow the stone to pass on its own.

FIGURE1. A 4-hrdelayedimageof thehepatobiliarystudyperformed with @Tc-DISIDA.There is fairly good uptake oftracer by the liverwith only a smallamountof blood-poolactivityremaining.Renalexcretionisseenwithmuchtracerintheurinarybladder.There is no evidenceof excretion into either the bowelor gallbladderconsistent with the liver scan―appearanceandstronglysuggestiveof commonbileduct obstruction.Thereisalso photopenia in the porta hepatis (arrows) probably due todilated ducts. (Published with permission from Clin Nuci Med1985;10:264.)

(.:,@ /L:Ll(i@ T

A

, -@

:‘@@

@,,-

LPO

B I

-_

FIGURE2. (A)Sonogramof the rightupperquadrant.Thegallbladdercontains low-levelechos indicatingsludge. There isalso an echogenic focus (curved arrow) with shadowing (smallarrows), representativeof a large gallstone.(B) Ultrasound @ewof thecommonbileduct(arrows)whichisdilatedandmeasures9 mm. (Publishedwith permissionfrom Clin Nuc! Med 1985;10:264.)

Over the following days, the patient's bilirubin gradually dropped and herjaundice resolved. It was felt thather common bile duct stone had passed. However, thepatient continued to have occult gastrointestinal bleeding similar to that before the ERCP, though the ERCPhad not shown any evidence ofan upper gastrointestinalbleeding site. The next step was to evaluate the lowergastrointestinal tract for bleeding and she was scheduledto have a barium enema. However, on the day that thiswas to be performed, the patient had a seizure and thena cardiopulmonary arrest. She was resuscitated, intubated, and transferred to the medical intensive care unit(MICU). The events that followed demonstrated thatshe had suffered a non-hemorrhagic stroke (noted oncomputed tomography) which probably caused the seizure. She also had suffered an acute anteroseptal myocardial infarction, although it was uncertain whetherthe myocardial infarction preceded the stroke. In theMICU, she was in cardiogenic shock and requiredpressors to maintain an adequate blood pressure. Following this event, she was unresponsive and believed to

1262 The Journal of Nuclear Medicine•Vol.32 •No. 6 •June 1991

A .-

r@@- .

. .@ -.,--

@ -@

FIGURE3. Thisfluoroscopic.imagewas obtainedduring. @.ERCP.Theendoscopeisseenintheduodenum witha catheter insertedthroughthe ampullaof vaterintothecommonbile duct. Contrast media infused into the common bileduct demonstratesdilationanda fillingdefect (arrows) in themid-portionof the duct representative of a calculus. Contrastalsofillstheintrahepaticbiliaryducts which appearnormel. (Publishedwith permission from Clln Nuci Med1985;10:264.)

have sustained significant cerebral damage. She still hadintermittent low-grade fevers and a repeat ultrasoundwas performed to visualize the biliary system. Thisdemonstrated a single stone in the gallbladder but theductal dilatation that had been seen on the previousultrasound was now resolved with a common ductdiameter of 4 mm, thus confirming that the commonbile duct stone had passed (Fig. 4).

Despite initial improvement in the patient's cardiacstatus, approximately 1 wk after the first cardiac arrest,she arrested again. Attempts at resuscitation were unsuccessful and the patient died.

DISCUSSION

This case demonstrates the utility of hepatobiliary imaging in cases of obstructive jaundice due to common bileduct stones. In such cases, decisions regarding treatmentcan be simplified once common bile duct obstruction isknown. With the advent ofERCP, choledocholithiasis cannow be treated without surgery. This is especially important in patients such as the one presented here where therisks of surgery are great.

Most referring clinicians may not be aware ofthe use ofhepatobiiary imaging for obstructive jaundice. Scanningof the biiary tree with an imino diacetic acid (IDA)compound such as DISIDA allows accurate detection ofobstruction of the common bile duct. It also can distinguish obstruction of the cystic duct, as is seen in acutecholecystitis, from obstruction ofthe main bile duct. Studies such as ultrasound and CT scans may detect dilationof the biliary tree, however, they are often less sensitive inacute biliary obstruction before the bile duct dilates. Sinceboth acute cholecystitis and biliary obstruction may causesimilar acute abdominal pain, a biliary scan appears to bethe diagnostic procedure of choice in a patient suspectedof biliary colic. In such patients, it may be appropriate toproceed from a biliary scan suggesting acute biliary ob

B

.@-4 .

i@_@ d@r@k.

--@ f

IFIGURE4. An ultrasoundperformedseveraldaysfollowingERCP.(A)Anechogenicstructure (curvedarrow)inthe gailbladder with shadowingis consistentwith a gallstone.(B)The cornmonbileduct (arrows)whichmeasures4 mm is a significantchange from the image in Figure 2B performed before ERCP,andindicatesthatthecommonbileductis nolongerobstructed.

struction to diagnostic and therapeutic ERCP rather thancontinuing the noninvasive diagnostic evaluation.

Common bile duct obstruction causes the characteristic“liverscan appearance―with hepatobiliary imaging: Thereis prompt and avid uptake ofthe tracer by the liver but noexcretion into the biliary system or bowel on either earlyor delayed images, presumably due to elevated biiarypressure that prevents the flow ofbile from the hepatocytesinto the biliary ducts (1,2). In cases with common hepaticduct distension, a photopenic defect may be seen in theporta hepatis. The “liverscan appearance―is commonwith most forms ofCBD obstruction, such as choledocholithiasis, primary or secondary tumors ofthe common bileduct (pancreatic carcinoma, cholangio carcinoma, ampullary carcinoma, metastatic tumors, etc.) and pancreatitis,but occasionally can be seen in cases of sepsis, peritonitis,hepatocellular disease, portal vein thrombosis, biliary atresia, and Dubin-Johnson syndrome (3—6).The majority ofcases are due to choledocholithiasis. It should be notedthat the predictive value of the “liverscan appearance―has been shown to drop in scans performed with p-isopro

Common Bile Duct Stones •Silfen and Long 1263

pyl imino diacetic acid (PIPIDA) when the bilirubin levelsrise above 10 mg/dl (3).

To understand how biliary scanning may be helpful inthe management of gallstone obstruction of the commonbile duct, we will review some important aspects of thepathophysiology of common duct stones and their nonoperative management. Over half a million cholecystectomies are performed annually in the United States, andabout 15% of these patients have a common duct stone(7). The first cholecystectomy was performed about 100years ago when diagnosis of common duct stones wasbased upon clinical symptoms and findings. Now we havea great array of diagnostic techniques, including oral cholangiogram, ultrasound, CT scan, hepatobiliary imaging,transhepatic cholangiogram, and ERCP. The therapeuticoptions for management of common duct stones nowinclude, not only surgery, but also percutaneous manipulations through the liver and retrograde endoscopic manipulations of the biliary tree. These may be supplementedwith agents that can dissolve cholesterol gallstones ormechanical techniques such as extracorporeal shock wavelithotripsy (ESWL) or pulsed laser to fragment stonespermitting easier extraction.

There are three types of gallstones and the compositionofthe stones affects their diagnosis and management. Themost common gallstone in the gallbladder is the cholesterolstone. Eighty-five percent of cholesterol stones are radiolucent, but calcium salts make the stone radio-dense inthe other 15% (8). The two other types of stones arecomposed primarily of calcium bilirubinate, which in itspurest form does not contain enough calcium by weightto make it radio-dense on a plain abdominal ifim. Calciumbilirubinate stones which form in the gallbladder, especially in older patients, are hard crystal in type and containan increased amount of calcium salts such as a calciumcarbonate; in about 85% of patients these stones are,therefore, radio-dense. These pigment stones are referredto as “blackstones.―

In contrast to the black stones that develop within thegallbladder, softer “brown―pigment stones form withinthe bile duct. These stones contain fewer calcium salts andare rarely radio-dense. The brown stones contain fattyacids such as propiomc acid not found in black stones.Most brown stones develop after removal of the gallbladder, but similar stones have been seen in patients living inthe Orient and are associated with a dilated biliaiy tree.These patients may not have stones within the gallbladder.Patients living in more industrialized urban societies inEurope and North America rarely have brown stones inthe bile duct ifthe gallbladder is intact (9).

Most bile duct stones found at the time of cholecystectomy in the United States are of the same composition asthe stones found within the gallbladder (9). That is, theyare either cholesterol stones or, less commonly, blackstones. For up to a year following cholecystectomy, moststones found within the bile duct will be cholesterol or

black stones, suggesting that these residual stones passedfrom the gallbladder and were not detected at the time ofsurgery. In contrast, patients found to have common ductstones more than a year after cholecystectomy will usuallyhave brown stones within the duct, consistent with arecurrent gallstone. Since most stones in the common ductwill either be cholesterol or brown stones, they are usuallyradiolucent. Examination of bile may be helpful sincecholesterol stones are associated with typical cholesterolcrystals and amorphous calcium bilirubinate may be seenwith pigment stones. During ERCP and attempted stoneextraction, samples of bile or bits of crystals may beobtained and examined microscopically to help distinguishpigment from cholesterol stones. Distinction of cholesteroland pigment stones is important if solvents to dissolvenonextractable cholesterol stones endoscopically are used.

The frequency of common duct stones found at cholecystectomy varies with the age of the patient. About 5%of patients under 60 yr of age who undergo cholecystectomy have common duct stones, whereas a third of thoseover 60 may have common duct stones (10). In somesurgical series in which the common duct was explored forsuspected stones, duct stones were found in only 60% ofpatients. Patients in whom no stones were found may havepassed them into the intestine. Alternatively, surgeons maymiss 2%-l5% of retained stones. Following cholecystectomy, patients with periampullary diverticuli have an increased risk of developing common duct stones (11).Sphincter of oddi pressure in patients with periampullarydiverticular has been reported to be lower than normaland there is an increased risk of such patients havinginfected bile. It is possible that bacteria within the biliarytree contributes to the development of brown stones.

About 90% of common duct stones may be removed atthe time of therapeutic retrograde cholangiography (12).Endoscopic sphincterotomy permits introduction of balloon-tip catheters and wire baskets into the biliary tree andstones that are small enough are extracted intact. Stonesgreater than 1.5 cm in diameter become more difficult toremove, and those over 2 cm frequently require fragmentation or dissolution before removal. Dissolution can beattempted with perfusion ofthe bile duct with monooctanoen or perhaps with methyl terbutyl ether, but these solvents do not dissolve brown stones and the side-effectsassociated with them have limited their use (12).

Fragmentation of large common duct stones can beperformed with strong wire baskets. Some centers areexperimenting with pulsed-laser fragmentation or electrohydrolic fragmentation of retained stones, two very promising techniques (13). The use of extracorporeal shockwave lithotripsy (ESWL) to fragment large common ductstones has been reported. A study by Sauerbruch et al.included 113 patients who had endoscopic sphincterotomyand placement of a biliary catheter either percutaneouslyor transnasally (a nasobiliary catheter) for introduction ofradio-contrast. Shock waves were then directed fluoroscop

1264 The Journalof NuclearMedicine•Vol. 32 •No. 6 •June 1991

ically toward the bile duct gallstones. Ninety percent ofstones were fragmented, and in 86% ofpatients, completeclearance of the bile duct was possible. Only patients whohad failed stone removal at ERCP were subjected toESWL. Since 90% of stones may be removed at the timeof endoscopic sphincterotomy, approximately 98% of allpatients with common duct stones may have nonoperativeclearance of their stones.

It is now widely accepted that post-cholecystectomypatients with common duct stones should have these removed endoscopically (15). In Europe and England about50% of patients with intact gallbladders are having common duct stones removed endoscopically. Generally, thesepatients tend to be older and poorer operative risks thanthe patients subjected to surgery, as was the case with thepatient presented here. Hospital stay following endoscopicsphincterotomy and common duct stone removal averagesabout 2 days in contrast to about 7 days for the operativecommon duct exploration. Mortality for endoscopic common duct stone removal is less than 1%, even in reportsinvolving mainly older and poor operative risk patients(12). If there are stones remaining in the gallbladderfollowing endoscopic sphincterotomy, about 15% of suchpatients will develop cholecystitis over the next few yearsand require operative cholecystectomy. Some of the gallstones may pass without causing significant symptoms,but most of the patients continue to have asymptomaticgallstones. The presence of cholangitis or acute gallstonepancreatitis is believed by many to be an indication forendoscopic sphincterotomy and nonoperative management. We generally treat the infection or pancreatitis tostabilize the patient prior to endoscopic management.

In summary it is accepted widely that poor operativerisk patients with common duct stones should be treatedwith endoscopic sphincterotomy and stone extraction. If apatient has an intact gallbladder and is a good operativerisk, there is controversy as to whether endoscopic techniques should be used. Some studies have suggested thatendoscopic removal ofcommon duct stones be performedand then operative removal of the gallbladder. The introduction oflaparoscopic cholecystectomy has further complicated this decision. We have treated several patientswith common duct stones immediately prior to electivelaparoscopic cholecystectomy. This combination has allowed rapid recovery ofthe patients and may prove appropriate for the younger good operative risk patients.

. If a patient has acute cholecystitis, surgical therapy will

probably be most appropriate. These are the very patientswho can be diagnosed most accurately with hepatobiliaryimaging, emphasizing the interaction between the newerdiagnostic and therapeutic techniques.

Hepatobiliary imaging may play a significant role inevaluation ofbiliary colic. Further work needs to be doneto determine the sensitivity and specificity of this technique in a patient with an acutely obstructed duct. However, the case presented here and data gathered from theliterature appears to provide evidence for its usefulness inthe appropriate setting.

REFERENCES1. Weissmann HS, Rosenblatt RR, Sugarman LA, Badia JD, Freeman LM.

Early diagnosis of acute common bile duct obstruction by Tc-99m-IDA(iminodiacetic acid) cholescintigraphy [Abstra.ctjfNuclMed l980;21:P41.

2. Noel AW, Velchik MG, Alavi A. The “liverscan―appearance in cholescintigraphy, a sign of complete bile duct obstruction. Clin Nuci Med1985;10:264—269.

3. Egbert RN, Braunstein P, Lyon KP, Miller DR. Total bileduct obstruction.Prompt diagnosis by hepatobiliary imaging. Arch Surg 1983;! 18:709—712.

4. Hughes KS, Marrangoni AG, Turbiner E. Etiology of the obstructivepattern in hepatobiliary imaging. Clin NuclMed l984;9:222—226.

5. Bar-Meir 5, Baron J, Seligson U, Gottesfeld F, Levy R, Gilat T.@HIDA cholescintigraphy in Dubin-Johnson and Rotor syndromes. Radiology 1982;l42:743—746.

6. KlingensmithWCIII,KuniCC,FritzbergAR.Cholescintigraphyin extrahepatic biliary obstruction. AIR l982;l39:65—70.

7. Mullen JL, Rosato EF, Ipsen J, Rosato FE. Gallstone characteristics in thediagnosis ofcholedocholithiasis. Ann Surg 1972;176:7l8—720.

8. Trotman BW, Petrdlla EJ, SolowayRD, Sanchez HM, Morris TA ill,Miller WT. Evaluation ofradiography lucency or opaqueness of gallstonesas a means of identifying cholesterol or pigment stones. Gastroenierologyl975;68:l563—1566.

9. Malet PF, Dabezies MA, Huang 0, Long WB, Gadacq TB., Soloway RD.Quantitative infrared spectroscopy of common duct gallstones. Gasiroenterologyl988;94:l2l7—122l.

10. Bane PS, Jacobson IM. Gallbladderdisease. In: Zakim D, BoyerT, eds.Hepazology, a zexthook ofliver disease, second edition. Philadelphia: WBSaundersCo.; 1990:1516.

11. LøtveitT, Foss OP. Osnes M. Biliarypigment and cholesterolcalculi inpatients with and without juxtapapillary duodenal diverticuli. Scand IGastro 198l;l6:241—244.

12. Long WB. Endoscopicallyassisteddiagnosis,removal and dissolutionofcholedocholithiasis.In: Cohen S. SolowayRD, ads. Contemporaryissuesin gastroenierology—gailsiones. New York: Churchill Livingstone;1985:4:259—265.

13. Cotton PB, Kozarek RA, schapiro RH, et al. Endoscopic laser lithothpsyoflarge bile duct stones. Gastroenierology l990;99:ll28-l 133.

14. Sauerbruch T, 5tern M. Fragmentation of bile duct stonesby extracorporealshock waves, a new approach to biliary calculi after failure of routineendoscopic measures. Gastroenierology l989;96:146—l52.

15. Summerfield JA. Biliary obstruction is best managed by endoscopists. Gut198829:741—745.

Common Bile Duct Stones •Silfen and Long 1265