Complications of gastrointestinal radiologic procedures: II. Complications related to biliary tract studies

Gadoxetic acid disodium-enhanced magnetic resonance imaging for biliary and vascular evaluations in preoperative living liver donors: comparison with gadobenate dimeglumine-enhanced MRI

PURPOSE

To compare gadoxetic acid disodium (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) with gadobenate dimeglumine (Gd-BOPTA)-enhanced MRI in preoperative living liver donors for the evaluation of vascular and biliary variations.

MATERIALS AND METHODS

Sixty-two living liver donors who underwent preoperative MRI were included in this study. Thirty-one patients underwent MRI with Gd-EOB-DTPA enhancement, and the other 31 underwent MRI with Gd-BOPTA enhancement. Two abdominal radiologists retrospectively reviewed dynamic T1-weighted and T1-weighted MR cholangiography images and ranked overall image qualities for the depiction of the hepatic artery, portal vein, hepatic vein, and bile duct on a 5-point scale and determined the presence and types of normal variations in each dynamic phase. Semiquantitative analysis for bile duct visualization was also conducted by calculating bile duct-to-liver contrast ratios.

RESULTS

No statistical differences were found between the two contrast media in terms of hepatic artery or bile duct image quality by the two reviewers, or in terms of portal vein image quality by one reviewer (P > 0.05). Gd-BOPTA provided better image qualities than Gd-EOB-DTPA for the depiction of hepatic veins by both reviewers, and for the depiction of portal veins by one reviewer (P < 0.01). The two contrast media-enhanced images had similar bile duct-to-liver contrast ratios (P > 0.05). Regarding diagnostic accuracies with hepatic vascular/biliary branching types, no significant differences were observed between the two contrast media (P > 0.05).

CONCLUSION

Gd-EOB-DTPA could be as useful as Gd-BOPTA for the preoperative evaluation of living liver donors, and has the advantage of early hepatobiliary phase image acquisition.

Evaluation of the biliary intestinal limb of a Roux-en-Y choledochojejunostomy using computed tomographic cholangiography

Computed tomographic (CT) findings involving the biliary intestinal limb of a Roux-en-Y choledochojejunostomy may be ambiguous because oral agents frequently do not reflux into that limb. We describe 2 cases where antegrade biliary intestinal limb opacification by intravenous CT cholangiography in the left lateral decubitus position obviated the need for biopsy of an apparent enlarging mass in the biliary intestinal limb. We conclude that CT cholangiography may help clarify the status of a Roux-en-Y choledochojejunostomy.

3D anatomical variations of hepatic vasculature and bile duct for right lateral sector of liver with special reference to transplantation

To achieve a safer living related liver transplantation (LRLT) using the right lateral sector, anatomical variations of the portal vein, hepatic artery and bile duct for the right lateral sector and their three dimentional (3D) relationship were assessed by integrated 3D-CT images. 52 patients who underwent contrast enhanced multi-detector row CT (MD-CT) and MD-CT cholangiography were enrolled. Data from contrast enhanced MD-CT were used to reconstruct the 3D images of the hepatic artery and portal vein. 3D images reconstructed from MD-CT data of the hepatic artery, portal vein and bile duct were integrated into a single image. The dual branching of the right lateral portal vein was observed in 22 (42.3%) patients. Three (5.8%) had dual right lateral ducts and 14 (26.9%) had dual right lateral arteries. Among them, "south-turning" artery and "north-turning" bile duct was observed in 22 (42.3%). "South-turning" artery and "south-turning" bile duct were 3 (5.8%). "North-turning" artery and "north-turning" bile duct were 2 (7.4%). Only 27 (51.9%) had single portal vein, bile duct and artery for the right lateral sector, those were preferable as candidates for right lateral sector graft transplantation. 3D anatomical variations of portal vein, artery and bile duct for the right lateral sector were complexed, and only half of the donor candidates had preferable hepatic structures for right lateral sector graft transplantation. Understanding of the 3D hepatic structures by 3D-CT may contribute to a better definition of anatomical contraindications for LRLT which may further results in more safe and widely applied right lateral sector graft LRLT.

Nonoperative imaging techniques in suspected biliary tract obstruction

Evaluation of suspected biliary tract obstruction is a common clinical problem. Clinical data such as history, physical examination, and laboratory tests can accurately identify up to 90% of patients whose jaundice is caused by extrahepatic obstruction. However, complete assessment of extrahepatic obstruction often requires the use of various imaging modalities to confirm the presence, level, and cause of obstruction, and to aid in treatment plan. In the present summary, the literature on competing technologies including endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiopancreatography (PTC), endoscopic ultrasound (EUS), intraductal ultrasonography (IDUS), magnetic resonance cholangiopancreatography (MRCP), helical CT (hCT) and helical CT cholangiography (hCTC) with regards to diagnostic performance characteristics, technical success, safety, and cost-effectiveness is reviewed. Patients with obstructive jaundice secondary to choledocholithiasis or pancreaticobiliary malignancies are the primary focus of this review. Algorithms for the management of suspected obstructive jaundice are put forward based on current evidence. Published data suggest an increasing role for EUS and other noninvasive imaging techniques such as MRCP, and hCT following an initial transabdominal ultrasound in the assessment of patients with suspected biliary obstruction to select candidates for surgery or therapeutic ERCP. The management of patients with a suspected pancreaticobiliary condition ultimately is dependent on local expertise, availability, cost, and the multidisciplinary collaboration between radiologists, surgeons, and gastroenterologists.

Role of magnetic resonance cholangiography in assessing biliary anatomy in right lobe living donors

BACKGROUND

The value of magnetic resonance cholangiography (MRC) in assessing potential adult-to-adult living liver transplant (ALDLT) donors remains poorly defined. The purpose of this study is to determine the accuracy of MRC in assessing biliary anatomy with intraoperative confirmation.

METHODS

A prospective cohort of 30 ALDLT donors who underwent right hepatectomy from October 2000 to July 2003 was evaluated. MRC was performed using a heavily T2 weighted radial slab technique. MRC was interpreted preoperatively by a radiologist and a surgeon and compared with the intraoperative biliary findings in all patients derived from cholangiography (IOC) and bile duct exploration. The sensitivity, specificity, and positive and negative predictive values of MRC for aberrant biliary anatomy were calculated.

RESULTS

MRC suggested normal, aberrant, and indeterminate biliary anatomy in 16, 12, and 2 donors, respectively. IOC revealed normal and aberrant biliary anatomy in 17 and 13 patients, respectively. MRC demonstrated biliary anatomy accurately in 27 of 30 patients. The sensitivity, specificity, positive predictive, and negative predictive values of MRC in detecting aberrant biliary anatomy were 92%, 100%, 100%, and 94%, respectively.

CONCLUSIONS

Preoperative MRC accurately depicts biliary anatomy in potential ALDLT donors and may guide the intraoperative management of the biliary tract.

Living donor candidates for right hepatic lobe transplantation: evaluation at CT cholangiography--initial experience

PURPOSE

To retrospectively evaluate computed tomographic (CT) cholangiography in the depiction of second-order biliary tract anatomy in living donor candidates for right hepatic lobe transplantation.

MATERIALS AND METHODS

Human research committee approval was obtained, informed consent was not required, and the study was compliant with the Health Insurance Portability and Accountability Act. The authors identified all living right-lobe liver donor candidates who underwent CT cholangiography at their institution between October 2001 (when CT cholangiography was introduced at the institution) and March 2003 (n = 62). There were 41 men (mean age, 36 years; range, 18-55 years) and 21 women (mean age, 40 years; range, 22-55 years). Two readers in consensus rated quality of second-order bile duct visualization at CT cholangiography on a four-point scale (0, not seen; 3, excellent visualization) and noted the presence of variant second-order biliary tract branching anatomy. CT cholangiography findings were compared with those at surgery in subjects who underwent right hepatic lobe retrieval (n = 24). In addition, adult donors who underwent right hepatic lobe retrieval between January 2000 and March 2003 (29 men, mean age, 35 years [range, 20-52 years]; 18 women, mean age, 38 years [range, 23-54 years]) were identified. Numbers of donors who underwent intraoperative cholangiography before and after the introduction of CT cholangiography were compared by using the Fisher exact test.

RESULTS

The mean second-order bile duct score at CT cholangiography was 2.9 (range, 2-3). Of 24 subjects who underwent right lobe retrieval, biliary tract anatomy determined at CT cholangiography was concordant with findings at surgery in 23 (96%). Variant second-order branching anatomy was seen in 13 subjects (54%) at surgery; one variant branch was missed at CT cholangiography. Of 47 subjects who underwent right hepatic lobe retrieval, significantly fewer subjects required conventional intraoperative cholangiography after the introduction of CT cholangiography (three of 24 subjects [12%]) than before (23 of 23 subjects; P < .0001).

CONCLUSION

CT cholangiography accurately depicts biliary tract anatomy in living donor candidates for right hepatic lobe transplantation, and donors who undergo preoperative CT cholangiography are unlikely to need conventional intraoperative cholangiography.

Computerized CT-Based 3D Visualization Technique in Living Related Liver Transplantation

INTRODUCTION

For living donor liver transplantation (LDLT) accurate diagnostic workup is essential. Multiple imaging approaches are currently used. Problems arise in the assessment of vascular and bile duct anatomy, liver graft volume, and vascular territories involved. A 3D visualization system that improves anatomic assessment, allows interactive surgery planning, and acts as an intraoperative guide with enhanced precision is required. Refinements in computed tomography (CT) technology with the introduction of multidetector-row CT scanners and implementation of mathematical methods on computerized digital data has enabled CT-based 3D visualizations.

MATERIALS AND METHODS

Sixteen LDLT candidates and three LDLT recipients were assessed by multislice CT examination. Image processing of the digital raw data for 3D visualization included segmentation and calculation of center lines. A hierarchical mathematical model representing the vascular and biliary tree was created. This allowed calculation of individual vascular territories.

RESULTS

3D CT-based visualization in LDLT facilitates diagnostic workup with high accuracy for analyses of vascular and bile duct variants, volumetry, and assessment of the optimal surgical splitting line of the living donor liver. Resultant areas of either arterial devascularization or venous congestion can be displayed and quantified preoperatively. The diagnostic method is of major impact on patient selection and directly influences intraoperative surgical guidance. The currently practiced "multiple imaging approach" approach, especially with regard to invasive diagnostics, can be avoided in the future.

Concordance of second-order portal venous and biliary tract anatomies on MDCT angiography and MDCT cholangiography

OBJECTIVE

We sought to investigate the concordance between second-order portal venous and biliary tract anatomies using MDCT angiography and MDCT cholangiography.

MATERIALS AND METHODS

We retrospectively identified 56 living related potential liver donors who underwent both MDCT angiography and MDCT cholangiography. Two reviewers independently rated axial images and 3D reconstructions of MDCT angiograms and cholangiograms as diagnostic or nondiagnostic with respect to depiction of second-order portal venous and biliary tract anatomies. In images rated as diagnostic, second-order portal venous and biliary tract anatomies were categorized as conventional or variant. The concordance between portal venous and biliary tract anatomies was analyzed using McNemar exact chi-square test.

RESULTS

All examinations were diagnostic. Second-order portal venous variants were seen in 10 (18%) and biliary branch variants were seen in 23 (41%) of the 56 patients. Patients with variant portal venous anatomy (6/10, 60%) were more likely to have variant biliary tract anatomy than patients with conventional portal venous anatomy (17/46, 37%; p < 0.01). The sensitivity of variant portal venous anatomy as a marker for variant biliary anatomy was 26% (6/23 patients).

CONCLUSION

Concordance between second-order portal venous and biliary tract anatomies is statistically significant. However, in our series, a number of patients with conventional portal venous anatomy had variant biliary anatomy; therefore, the finding of conventional portal venous anatomy does not obviate preoperative biliary tract imaging in patients before liver donation.

Diagnostic role of secretin-enhanced MRCP in patients with unsuccessful ERCP

AIM: To evaluate the value of MR cholangiopancreatography (MRCP) in patients in whom endoscopic retrograde cholangiopancreatography (ERCP) was unsuccessfully performed by experts in a tertiary center.

METHODS: From January 2000 to June 2003, 22 patients fulfilled the inclusion criteria. The indications for ERCP were obstructive jaundice (n = 9), abnormal liver enzymes (n = 8), suspected chronic pancreatitis (n = 2), recurrent acute pancreatitis (n = 2), or suspected pancreatic cancer (n = 1). The reasons for the ERCP failure were the postsurgical anatomy (n = 7), duodenal stenosis (n = 3), duodenal diverticulum (n = 2), and technical failure (n = 10). MRCP images were evaluated before and 5 and 10 min after i.v. administration of 0.5 IU/kg secretin.

RESULTS: The MRCP images were diagnosed in all 21 patients. Five patients gave normal MR findings and required no further intervention. MRCP revealed abnormalities (primary sclerosing cholangitis, chronic pancreatitis, cholangitis, cholecystolithiasis or common bile duct dilation) in 10 patients, who were followed up clinically. Four patients subsequently underwent laparotomy (hepaticojejunostomy in consequence of common bile duct stenosis caused by unresectable pancreatic cancer; hepaticotomy + Kehr drainage because of insufficient biliary-enteric anastomosis; choledochoj-ejunostomy, gastrojejunostomy and cysto-Wirsungo gastrostomy because of chronic pancreatitis, or choledochojejunostomy because of common bile duct stenosis caused by chronic pancreatitis). Three patients participated in therapeutic percutaneous transhepatic drainage. The indications were choledocholithiasis with choledochojejunostomy, insufficient biliary-enteric anastomosis, or cholangiocarcinoma.

CONCLUSION: MRCP can assist the diagnosis and management of patients in whom ERCP is not possible.

Biliary tract depiction in living potential liver donors: comparison of conventional MR, mangafodipir trisodium-enhanced excretory MR, and multi-detector row CT cholangiography--initial experience

PURPOSE

To compare biliary tract depiction in living potential liver donors at conventional magnetic resonance (MR), mangafodipir trisodium-enhanced excretory MR, and multi-detector row computed tomographic (CT) cholangiography.

MATERIALS AND METHODS

Eight living potential liver donors underwent iodipamide meglumine-enhanced CT cholangiography. Eight different potential liver donors then underwent conventional MR cholangiography and mangafodipir trisodium-enhanced excretory MR cholangiography. Two readers independently scored all first-, second-, and third-order biliary branches with a four-point scale from 0 (not seen) to 3 (excellent visualization). Interobserver agreement was calculated by using the weighted kappa statistic. Scores were compared between imaging modalities by using generalized estimating equations. Imaging findings of second-order biliary tract anatomy were compared with intraoperative findings for nine patients.

RESULTS

Interobserver agreement for overall biliary tract visualization was good for CT, conventional MR, and excretory MR cholangiography (with weighted kappa values of 0.76, 0.66, and 0.79, respectively). The mean second-order biliary branch visualization scores for readers 1 and 2, respectively, were significantly higher at CT cholangiography (2.81 and 2.75) than at conventional MR (1.84 and 1.75, P <.001), excretory MR (2.00 and 2.06, P <.001), and combined conventional and excretory MR cholangiography (2.31 and 2.25, P <.01). At CT, conventional MR, and excretory MR cholangiography, respectively, second-order biliary branching anatomy was discernible in eight, five, and seven patients, with second-order biliary branch variants seen in three, two, and two patients. Surgical findings confirmed the pattern of second-order biliary branching seen at CT in five patients, that seen at conventional MR imaging in one patient, and that seen at excretory MR cholangiography in three patients. At surgery, one case of variant biliary anatomy was found to have been missed at CT cholangiography.

CONCLUSION

In living potential liver donors, CT cholangiography enables significantly better biliary tract visualization than conventional or excretory MR cholangiography either alone or in combination.

Reevaluation of spiral CT cholangiography: basic considerations and reliability for detecting choledocholithiasis in 80 patients

PURPOSE

The purpose of this work was to reevaluate the characteristics and diagnostic accuracy of spiral CT cholangiography (CTC) for detecting biliary calculi.

METHOD

Spiral CTC was performed in 133 patients with suspected biliary or pancreatic diseases. All source images were reviewed by two radiologists who were unaware of final diagnoses. Attenuation values of bile were correlated with biochemical data and visualization of anatomic detail. The statistical measures in detecting the presence of choledocholithiasis were calculated in 80 patients with confirmed diagnoses.

RESULTS

Statistically significant correlations were found between the degree of biliary enhancement and both serum bilirubin and alkaline phosphatase levels. Of the 80 patients, 18 (23%) had choledocholithiasis and 62 did not. Observers diagnosed them with a sensitivity of 89% and a specificity of 98%. A mild adverse reaction to contrast material was observed in three (2.3%) patients.

CONCLUSION

Spiral CTC is a reliable, noninvasive, and accessible technique for detecting choledocholithiasis.

Diagnosing bile duct stones: comparison of unenhanced helical CT, oral contrast-enhanced CT cholangiography, and MR cholangiography

OBJECTIVE

In this investigation we compared the diagnostic performance of unenhanced helical CT, oral contrast-enhanced CT cholangiography, and MR cholangiography for the diagnosis of choledocholithiasis.

SUBJECTS AND METHODS

Fifty-one patients referred for endoscopic retrograde cholangiography of suspected biliary stones were studied with unenhanced helical CT, MR cholangiography, and helical CT performed after oral administration of a cholangiographic contrast agent (iopodic acid). The studies were randomized for interpretation. Two radiologists evaluated the images by consensus and determined the presence and location of stones. We used retrograde cholangiography findings as the standard of reference. Sensitivity and specificity (with 95% confidence intervals [CIs]) of the three examinations were calculated and compared using the exact form of the McNemar test.

RESULTS

Bile duct stones were revealed with retrograde cholangiography in 26 patients (51%). Sensitivity was 65% (95% CI, 44.4-82%) for unenhanced helical CT, 92% (95% CI, 73-99%) for CT cholangiography, and 96% (95% CI, 78-99%) for MR cholangiography. Specificity was 84% (95% CI, 63-95%) for unenhanced helical CT, 92% (95% CI, 73-99%) for CT cholangiography, and 100% (95% CI, 83-100%) for MR cholangiography. The sensitivity of CT cholangiography and MR cholangiography was significantly higher than that of unenhanced helical CT (p<0.01). Differences in specificity were not significant.

CONCLUSION

Our results indicate that oral contrast-enhanced CT cholangiography and MR cholangiography are significantly more sensitive than unenhanced helical CT for the detection of bile duct calculi.

Helical CT cholangiography with three-dimensional volume rendering using an oral biliary contrast agent: feasibility of a novel technique

OBJECTIVE

We evaluated the feasibility and image quality of a new noninvasive biliary imaging technique: helical CT cholangiography with three-dimensional volume rendering using an oral biliary contrast agent.

SUBJECTS AND METHODS

Nineteen subjects including five healthy volunteers and 14 patients underwent helical CT cholangiography. Subjects ingested 6.0 g of iopanoic acid 6-10 hr before undergoing imaging. Axial data were used to construct three-dimensional volume-rendered cholangiograms. Two radiologists, an endoscopist, and a laparoscopic surgeon reviewed the images and evaluated overall image quality. In the 14 patients, findings from CT cholangiography were compared with those from ERCP, surgery, and intraoperative cholangiography.

RESULTS

All segments of the biliary tree were opacified in all volunteers except one, in whom the intrahepatic ducts were not opacified. Image quality was good to excellent in all volunteers. Anomalous cystic duct insertions were seen in two volunteers. Opacification of the biliary tree was rated as acceptable to excellent in nine patients and suboptimal in five. In five patients with good or excellent opacification, the biliary anatomy correlated with findings on intraoperative cholangiography or ERCP. CT cholangiography revealed additional conditions (gallbladder varices and acute pancreatitis) and variant anatomy in three patients.

CONCLUSION

Results of this pilot project suggest that obtaining CT cholangiograms using an oral biliary contrast agent is a feasible, noninvasive method for revealing biliary anatomy. However, visualization of the biliary tree was suboptimal in 36% of the patients, which represents a limitation of this technique.

Bile duct stones: diagnosis with MR cholangiography and helical CT

MR cholangiography (MRC) is a highly accurate, noninvasive method for diagnosing bile duct stones. Various breath-hold and non-breath-hold techniques for MRC have been used successfully to depict stones in the intrahepatic and extrahepatic biliary tree. Although detection of stones with MRC is usually straightforward, attention to technical details is important to avoid false-negative and false-positive interpretations. With the advent of helical CT, other options for noninvasive imaging of the bile ducts, such as CT cholangiography, are now available. CT techniques are especially useful when MRI is unavailable or contraindicated, or when the quality of MRC images is suboptimal.

Biliary tract imaging

In addition to the detection of gallstones, common bile duct stones, and narrowed and dilated bile ducts, recent advancements in imaging techniques now make it possible to diagnose microlithiasis, pathology of normal-size ducts, and dysfunction of the gallbladder and the sphincter of Oddi (SO). More and more frequently, noninvasive imaging techniques obviate the risk of invasive investigation. These techniques can also take the place of unsuccessful or contraindicated direct cholangiography, and they play an essential role in treatment planning and diagnosis of postoperative complications. Transabdominal ultrasonography (TUS) remains fundamental for initial assessment of the biliary tract. Technical developments make magnetic resonance cholangiopancreatography the most promising diagnostic technique of the biliary tract. Endoscopic ultrasonography (EUS) is most helpful for detection of microlithiasis and evaluation of the ampullary region, the periductal structures, and the regional lymph nodes in neoplastic diseases. Cholescintigraphy is most valuable to assess bile dynamics in the diagnosis of gallbladder and SO dysfunction and in postoperative bile leakage.

Value of MR cholangiography in the diagnosis of obstructive diseases of the biliary tree: a study of 58 cases

OBJECTIVE

The aim of this study was to evaluate magnetic resonance cholangiography (MRC) in the diagnosis of biliary tree obstruction.

METHODS

Fifty-eight consecutive patients underwent MRC (GYROSCAN ACS II 1.5 Tesla, TSE T2 axial/coronal-MIP sequences) for clinical and biochemical signs of main bile duct obstruction. MRC images were interpreted by two radiologists and consensus was established according to presence or absence of main bile duct dilation, choledocholithiasis, and malignant or benign stricture. MRC was compared to a final diagnosis established by ultrasound and CT in 19 cases, endoscopic retrograde cholangiopancreatography (ERCP) in 25, intraoperative cholangiography and exploration in 14, and clinical, biochemical, and histological presentation when relevant. Included were single or multiple choledocholithiasis (28, including 11 < or = 3 mm), malignant (10) and benign (12) strictures, and intrahepatic cholestasis (9).

RESULTS

Overall, MRC was sensitive (94%) and specific (92%) in detecting main bile duct dilation and choledocholithiasis (86 % and 97 %), but was less sensitive (64%) for small stones < or = 3 mm. Sensitivity for stones > 3 mm was 100%. For benign and malignant strictures, MRC was less sensitive (67% and 80%) but remained specific (98% and 96%). In the detection of normal main bile duct, MRC was highly sensitive (100%) and specific (94%). Diagnostic accuracy ranged from 91% to 98%.

CONCLUSION

MRC appears to be specific for choledocholithiasis and sensitive except for small stones. Results for biliary stricture are less satisfactory, but remain specific. Our data confirm that MRC can be useful in the diagnostic workup of main bile duct obstruction.

Preoperative assessment for laparoscopic cholecystectomy: feasibility of using spiral computed tomography

OBJECTIVE

The authors investigated the preoperative feasibility of using spiral computed tomography (SCT) after intravenous infusion cholangiography (IVC-SCT) for laparoscopic cholecystectomy.

SUMMARY BACKGROUND DATA

In laparoscopic cholecystectomy, the aberrant or unusual anatomy of the bile duct and severe inflammation or adhesions around the gallbladder sometimes require a conversion to open surgery.

METHODS

Laparoscopic cholecystectomies (LC's) were attempted on 440 patients, and preoperative IVC-SCT also was attempted in all of these patients. Using this spiral scanning technique, the bile ducts, cystic duct, and gallbladder were assessed for contour abnormalities, relative position, and filling defects. Forty-seven patients were diagnosed with having stones in their common bile duct or common hepatic duct.

RESULTS

Three-hundred eighty-seven patients out of the 440 patients (88.0%) who were subjected to IVC-SCT had the length and course of their cystic duct successfully determined. Anomalous unions of the cystic duct were seen in 59 (15.2%) of 387 patients with respect to the operative findings, and 48 of 440 patients (10.9%) had severe adhesions to Calot's triangle and the surrounding tissues. In these 48 patients, 45 patients (94%) had a nonvisualized cystic duct on IVC-SCT. The preoperative assessment of the feasibility (dense adhesions obscuring Calot's triangle) of using IVC-SCT demonstrated that the sensitivity, specificity, and accuracy were 93%, 98%, and 94%, respectively. Five patients had to be converted to open surgery, and the overall morbidity rates for patients undergoing laparoscopic cholecystectomy was 0.9% (4 of 440).

CONCLUSIONS

The most important factor in assessing the feasibility of using laparoscopic cholecystectomy is not the nonvisualized gallbladder, but the nonvisualized cystic duct on IVC-SCT. IVC-SCT may be of benefit to those patients scheduled to undergo laparoscopic cholecystectomy.

Magnetic resonance imaging in evaluation of the common bile duct

BACKGROUND

The ideal method for evaluation of the common bile duct (CBD) before or during cholecystectomy remains controversial. Magnetic resonance cholangiography (MRC) is a new, promising technique. A prospective evaluation is reported.

METHOD

Sixty-one patients (45 women) were studied by MRC. There were 29 patients with symptomatic gallstone disease and without clinical, biochemical or ultrasonographic evidence of CBD stones (group 1); 28 of them also underwent intraoperative cholangiography (IOC). In addition, there were 21 patients with symptomatic gallstone disease, with mild biochemical and ultrasonographic signs of CBD involvement (group 2), of whom 19 underwent IOC, and 11 patients with symptomatic CBD stones (group 3), nine of whom had preoperative endoscopic retrograde cholangiopancreatography (ERCP) following MRC.

RESULTS

MRC showed that no patient in group 1 and three patients in group 2 had CBD stones. Three patients (one in group 1, two in group 2) did not undergo IOC because of technical or clinical problems. In group 3, ERCP confirmed the results of MRC in nine patients. Two patients underwent open surgery because of ultrasonographic, MRC and radiographic signs of pancreatic malignancy.

CONCLUSION

MRC could replace IOC and ERCP for identification of asymptomatic CBD stones. In symptomatic patients MRC combined with other non-invasive imaging techniques can direct the surgeon to appropriate management.

Three-dimensional helical computed tomography with intravenous cholangiography for sclerosing cholangitis manifested as postcholecystectomy symptom

A 46-year-old woman who had upper abdominal pain 10 years after cholecystectomy, and who had incidental sclerosing cholangitis (SC), was investigated by three-dimensional helical computed tomographic (3-DHCT) cholangiography with contrast medium, because endoscopic retrograde cholangiography (ERC) was unsuccessful and a second ERC was not permitted by the patient. The cholangiogram demonstrated annular strictures of the bilateral hepatic duct at the confluence of the common hepatic duct, and dilatation of the left intrahepatic biliary duct. Although we could not clarify the cause of the biliary tract deformity at the time of the 3-DHCT, the tentative diagnosis of postcholecystectomy deformity of the biliary tree led to successful treatment by right liver lobectomy and hepaticojejunostomy. Histologic findings were compatible with SC. From this experience and the literature, we suggest that 3-DHCT cholangiography with contrast medium can contribute to the preoperative diagnosis of morphological changes in the biliary tree in patients with postcholecystectomy symptoms.

The use of intravenous cholangiography in teaching hospitals: a survey

Thirty academic radiology departments active in biliary imaging were surveyed to document how frequently intravenous cholangiography (IVC) was being performed. Over a 10-year period the number of examinations has decreased precipitously from approximately 1728 in 1976 to 8 in 1986. This coincides with the increased availability of alternative procedures. The availability of new contrast agents with improved diagnostic yield and decreased toxicity suggests that its use may have been prematurely abandoned.

Current practice in biliary surgery

A questionnaire enquiring about current practices in biliary surgery was sent to over 25 per cent of consultant general surgeons in the UK; 90 per cent replied. Only 56 per cent use antibiotic prophylaxis for elective cholecystectomy, and 84 per cent for emergency cholecystectomy. Duration of use, choice of agent and absence of prophylaxis for high-risk cases were inappropriate in up to 20 per cent of cases. Of the respondents 84 per cent routinely perform operative cholangiography and use T tubes, and 75 per cent routinely place a peritoneal drain after cholecystectomy. Despite controversies in the literature, most UK surgeons still follow traditional practices in biliary surgery.

Diagnosis of cholestasis: an analytic view

The authors analyzed two invasive procedures used to visualize the biliary tree, endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC), and also explored the utility of preinvasive workups for patients with suspected cholestasis. For this analysis they used published ranges for success, fatality, complications, diagnostic accuracies of the procedures, and prognostic information about the underlying diseases. The choice between ERCP and PTC was found to be a "close call," but ERCP was generally favored as the first-choice procedure. The results suggest that noninvasive imaging does not help decide between ERCP and PTC. Although noninvasive imaging may identify those patients with common duct dilation, the higher success rate with PTC in these patients is offset by a slightly higher mortality rate. Consequently, the choice between ERCP and PTC remains close even if ultrasound has shown that biliary ducts are dilated. Furthermore, it is shown that these noninvasive tests are most useful when they can conclusively determine the presence or absence of biliary obstruction. For many patients, noninvasive imaging will not obviate the need for invasive tests.

Percutaneous transhepatic cholangiography, drainage, and biopsy in patients with malignant biliary obstruction. An alternative to surgery

We retrospectively reviewed our experience with 100 patients with malignant biliary obstruction who underwent percutaneous transhepatic cholangiography alone or in combination with percutaneous drainage. On the basis of this study, we found percutaneous transhepatic cholangiography to be a safe and effective procedure for demonstrating the site, nature, and extent of obstructive lesions. Percutaneous cholangiography was successful in 98 percent of patients, and only one patient (4.1 percent) had a significant complication. Likewise, percutaneous drainage has been highly successful in providing palliative biliary drainage in patients with unresectable malignancies. Percutaneous drainage was successful in 74 of 76 patients (97.4 percent). Five of these patients (6.6 percent) had significant complications, including one death (1.3 percent). The mean survival period of patients with carcinoma of the bile ducts was 29 months, whereas for those with carcinoma of the pancreas it was 3.4 months. Thus, mortality and complication rates were lower, and patient survival rates were similar or improved when compared with those of patients palliated by surgical bypass. Percutaneous drainage thus provides a satisfactory alternative to surgery. Biopsy performed in conjunction with these procedures can often provide a definitive diagnosis. Final tissue diagnoses were made in 20 of 23 patients (87 percent) by transcatheter or percutaneous biopsy.