The diagnostic accuracy of magnetic resonance cholangiopancreatography and ultrasound compared with direct cholangiography in the detection of choledocholithiasis

Gallbladder Disorders: A Comprehensive Review

Gallbladder disorders encompass a wide breadth of diseases that vary in severity. We present a comprehensive review of literature for the clinical presentation, pathophysiology, diagnostic evaluation, and management of cholelithiasis-related disease, acute acalculous cholecystitis, functional gallbladder disorder, gallbladder polyps, gallbladder hydrops, porcelain gallbladder, and gallbladder cancer.

ACR Appropriateness Criteria® Jaundice

Jaundice is the end result of myriad causes, which makes the role of imaging in this setting particularly challenging. In the United States, the most common causes of all types of jaundice fall into four categories including hepatitis, alcoholic liver disease, blockage of the common bile duct by a gallstone or tumor, and toxic reaction to a drug or medicinal herb. Clinically, differentiating between the various potential etiologies of jaundice requires a detailed history, targeted physical examination, and pertinent laboratory studies, the results of which allow the physician to categorize the type of jaundice into mechanical or nonmechanical causes. Imaging modalities used to evaluate the jaundiced patient (all etiologies) include abdominal ultrasound (US), CT, MR cholangiopancreatography, endoscopic retrograde cholangiopancreatography and endoscopic US. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Accuracy of Imaging Modalities in Choledocholithiasis: A Real-Life Data

In this retrospective study of real-life data, we aimed to determine the diagnostic accuracy in patients with choledocholithiasis of some current imaging modalities, including ultrasonography (US), computerized tomography (CT), magnetic resonance cholangiopancreatography (MRCP), and endoscopic retrograde cholangiopancreatography (ERCP). This study utilized a database of imaging records from 86 consecutive patients with ERCP-proven choledocholithiasis in a single-center outpatient clinic. Features of the stones found, namely number, size, localization, choledochal dilation and cholestasis, were determined using various imaging modalities and liver function tests (LFTs). Our study focused on a total of 86 patients (43 female; 43 male) who underwent the ERCP procedure. Hepatobiliary ultrasound was performed in 71 (82.6%); MRCP in 59 (68.6%); and CT in 13 (15.1%) patients. All 86 patients had choledocholithiasis: 59 (68.6%) with multiple stones and 21 (24.4%) with stones over 10 mm in diameter. Sensitivity for the presence of choledocholithiasis was 40.8% for US, 76.9% for CT, and 86.4% for MRCP, where ERCP was taken as the reference method. Even though US, CT, and MRCP are widely used as noninvasive imaging modalities for CL, in our real-life data their sensitivity for choledocholithiasis was lower than expected. MRCP is preferred when a nontherapeutic but only diagnostic evaluation is aimed for; however, while highly competent in establishing the level of choledochal dilation, it had a low yield in differentiating the localization, size, and number of the stone(s).

Is Preoperative Evaluation of the Biliary Tree Necessary in Uncomplicated Gallstone Disease?

Aim:

To analyse if preoperative radiology is of value in patients with uncomplicated gallstone disease.

Material:

312 patients intended for laparoscopic cholecystectomy were randomly allocated to undergo preoperative radiology (intravenous cholangiography or magnetic resonance cholangiography) or to a control group. Intraoperative cholangiography was not used routinely in either group.

Results:

There was no bile duct injury and no difference in complication frequency between the two groups. The incidence of common bile duct stones was 3,8 % within the first postoperative year with no statistical difference between the two groups.

Conclusions:

Routine preoperative evaluation of the bile tree seems unnecessary before laparoscopic cholecystectomy in patients with uncomplicated gallstone disease.

Has intraoperative cholangiography during laparoscopic cholecystectomy become obsolete in the era of preoperative endoscopic retrograde and magnetic resonance cholangiopancreatography?

BACKGROUND

Preoperative ERCP, magnetic resonance cholangiopancreatography (MRCP), and intraoperative cholangiography (IOC) are standard procedures in evaluating patients with suspected choledocholithiasis. This study evaluates the changing practice patterns over time of these 3 procedures in a large cohort of patients undergoing laparoscopic cholecystectomy (LC) at a single tertiary care center.

STUDY DESIGN

Data from all patients undergoing an LC with or without preoperative ERCP, MRCP, or an IOC from January 1, 2004 to December 31, 2013 were retrospectively reviewed from billing data obtained by CPT code and analyzed by chi-square testing.

RESULTS

During 10 years, 7,427 patients underwent successful LC. The number of patients undergoing successful IOC (11.9% to 7.6%) or preoperative ERCP (7.2% to 1.5%) decreased significantly during that time interval (p < 0.01). In the last 6 years, 4,506 patients underwent successful LC. The number of patients from this group undergoing a preoperative MRCP (0.9% to 8.6%) or MRCP and ERCP (0.4% to 3.6%) increased significantly (p < 0.001).

CONCLUSIONS

Despite a shift from IOC and preoperative ERCP to preoperative MRCP alone or with ERCP, a significant percentage (7.6%) of patients still underwent IOC in 2013. Use of IOC during LC has decreased but is not considered obsolete, rather, it remains a valuable tool for the evaluation of bile duct anatomy, bile duct injury, or suspected choledocholithiasis. Intraoperative cholangiography during uncomplicated LC should be emphasized in teaching programs to insure general surgery resident competency with the procedure.

Cholestatic liver disease

The care of the patient with cholestasis hinges on identifying the etiology, treating reversible causes, and managing chronic cholestatic processes. PBC and PSC are important causes of chronic cholestasis, and are the most common causes of cholestatic liver disease. Effective therapy is available for patients with PBC, whereas none exists for patients with PSC. Awareness of the complications that may be associated with cholestasis and implementing the appropriate management are essential.

The Value of Magnetic Resonance Cholangio-Pancreatography (MRCP) in the Detection of Choledocholithiasis

INTRODUCTION

Magnetic Resonance Cholangio-Pancreatography (MRCP) is a non-invasive radiological investigation which can be performed rapidly and which does not expose the patients to ionised radiations or iodinated contrast material. The present study was conducted to evaluate the role of MRCP in detection of Common Bile Duct (CBD) stones in patients with suspected choledocholithiasis.

MATERIAL AND METHODS

This prospective study included 30 patients with a suspicion of choledocholithiasis which was based on clinical evaluation, biochemical or radiological investigations. Ultrasonography and MRCP were performed in all patients. All patients underwent open surgery. CBD exploration was performed in all patients, either due to presence of palpable stones or due to the presence of dilated CBD (> 7 mm). Demonstration of CBD stones intra-operatively was considered the 'gold standard' for their presence, defined as stones visualised and extracted or attempted for extraction during surgical CBD exploration.

RESULTS

Intra-operatively, 21 (70%) out of 30 patients had cholelithiasis. 26 (86.67%) out of 30 patients had dilated CBD stones intra-operatively. In 20 (66.67%) out of 30 patients, choledocholithiasis was detected intra-operatively. The sensitivity, specificity, positive and negative predictive value of ultrasonography in detecting CBD stones in the present study was 65%, 60%, 76.47% and 46.15% respectively. The sensitivity, specificity, positive and negative predictive value of MRCP in diagnosis of CBD stones in the present study was 95%, 90%, 95% and 90% respectively.

CONCLUSIONS

MRCP is a non-invasive investigation without complications and it has high sensitivity, specificity and positive and negative predictive values in detection of CBD stones. MRCP should be done in all cases with a suspicion of CBD stones, where facilities and expertise are available.

Accuracy of magnetic resonance cholangiopancreatography for diagnosing stones in the common bile duct in patients with abnormal intraoperative cholangiograms

BACKGROUND

Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive method for diagnosing choledocholithiasis. It is said to be as accurate as the gold standard endoscopic retrograde cholangiopancreatography (ERCP) for detecting common bile duct (CBD) stones. A study was needed to look at the accuracy of MRCP compared with intraoperative cholangiography (IOC) for detecting stones in the CBD. The aim of this study was to evaluate the diagnostic accuracy of MRCP in patients with choledocholithiasis diagnosed with IOC.

METHODS

This was a retrospective study looking at patients who underwent IOC. Results were compared with respective preoperative MRCP results if available.

RESULTS

Four hundred twenty patients who underwent IOC were reviewed and met criteria for the study. Seventy patients had preoperative MRCP. Accuracy of MRCP when compared with IOC was 70%.

CONCLUSIONS

MRCP has a high rate of false normal results compared with IOC and is not as accurate as more invasive techniques. There is no need for preoperative MRCP in patients with suspected choledocholithiasis caused by stones.

Care of the cholestatic patient

Cholestasis is defined as impairment of bile formation or bile flow. Care of the patient with cholestatic features is dependent on identifying the cause of the cholestasis, initiating appropriate treatment of reversible conditions, and the recognition and management of cholestasis-specific complications. Cholestasis may include extrahepatic ducts and intrahepatic bile ducts, or may be limited to one or the other. Jaundice and pruritus are the hallmarks of cholestasis clinically but biochemical evidence may, and often does, precede the clinical manifestations.

Contrast-enhanced MR cholangiography: comparison of Gd-EOB-DTPA and Mn-DPDP in healthy volunteers

OBJECTIVE

The purpose of this study was to compare the biliary enhancement dynamics of gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid (Gd-EOB-DTPA) and mangafodipir trisodium (Mn-DPDP) for contrast-enhanced MR cholangiography (MRC) in healthy subjects.

METHODS

15 healthy volunteers underwent MRI at 1.5 T with volumetric interpolated breath-hold examination sequence. Each volunteer was scanned once for each contrast agent. The signal-to-noise ratio (SNR) of the liver parenchyma and common hepatic duct (CHD) and the contrast-to-noise ratio (CNR) of CHD to liver parenchyma were evaluated and compared before and at several time points (5, 15, 30, 45, 60, 90, and 120 min) after injection of each agent.

RESULTS

SNR was significantly higher for Gd-EOB-DTPA than for Mn-DPDP in liver parenchyma after 5 min and in CHD after 15 min (p<0.05). CNR of CHD to liver parenchyma using Gd-EOB-DTPA showed an initial decrease at 5 min post-injection followed by a steep increase to a peak at 15 min post-injection. CNR using Mn-DPDP showed a steady increase to a peak at 15 min post-injection without an initial decrease. At 15 min, the value of CNR was significantly higher for Gd-EOB-DTPA than for Mn-DPDP (p<0.05).

CONCLUSION

For both contrast agents, CNR reached a peak at 15 min after contrast injection. At this time point, CNR of Gd-EOB-DTPA was significantly higher than that of Mn-DPDP. Therefore, Gd-EOB-DTPA may provide better contrast-enhanced MRC than Mn-DPDP at 15 min after contrast administration.

Recurrent acute pancreatitis: clinical profile and an approach to diagnosis

BACKGROUND AND AIMS

Though recurrent acute pancreatitis is often seen in clinical practice, there are few comprehensive articles on this entity. The aim of this study therefore was to assess the etiological and clinical profile as well as diagnostic yield of non-invasive and invasive tests in this group of patients.

METHODS

All patients with recurrent acute pancreatitis seen from 2002 to 2007 were included in the study, retrospectively. Clinical information, investigation, and treatment data were collected for all patients by a standardized review of medical charts. Diagnostic tests were grouped into level one (non-invasive) and level two (invasive) tests and their yield was assessed. Comparison was made between the group with known etiology and idiopathic group to look for significant differences.

RESULTS

A total of 188 patients with recurrent acute pancreatitis were seen during the study period. Common etiological factors were biliary disease (37%), pancreas divisum (8.5%) and alcohol (6.4%). Multiple etiologies were seen in 7% of cases, and no cause was found in 32.4%. The diagnostic yield of level-one investigation (non-invasive) was 29.3%. Level-two tests (invasive) identified presumptive etiologies in 38.3% of cases. Complications developed in 12.2% and there was no mortality. Clinical features and complications were similar in the idiopathic group and those with known etiology.

CONCLUSIONS

Etiological diagnosis was obtained in 67.6% of patients after comprehensive diagnostic work up. Diagnosis in the majority of patients could only be reached after invasive tests (bile crystal analysis, EUS, ERCP). Early diagnosis and etiology-based therapy is the key to optimum patient outcome.

Prospective evaluation of a selective approach to cholangiography for suspected common bile duct stones

INTRODUCTION

Common bile duct (CBD) stones can cause serious morbidity or mortality, and evidence for them should be sought in all patients with symptomatic gallstones undergoing cholecystectomy. Routine intra-operative cholangiography (IOC) involves a large commitment of time and resources, so a policy of selective cholangiography was adopted. This study prospectively evaluated the policy of selective cholangiography for patients suspected of having choledocholithiasis, and aimed to identify the factors most likely to predict the presence of CBD stones positively.

PATIENTS AND METHODS

Data from 501 consecutive patients undergoing laparoscopic cholecystectomy (LC) for symptomatic gallstones, of whom 166 underwent IOC for suspected CBD stones, were prospectively collected. Suspicion of choledocholithiasis was based upon: (i) deranged liver function tests (past or present); (ii) history of jaundice (past or present) or acute pancreatitis; (iii) a dilated CBD or demonstration of CBD stones on imaging; or (iv) a combination of these factors. Patient demographics, intra-operative findings, complications and clinical outcomes were recorded.

RESULTS

Sixty-four cholangiograms were positive (39%). All indications for cholangiogram yielded positive results. Current jaundice yielded the highest positive predictive value (PPV; 86%). A dilated CBD on pre-operative imaging gave a PPV of 45% for CBD calculi; a history of pancreatitis produced a 26% PPV for CBD calculi. Patients with the presence of several factors suggestive of CBD stones yielded higher numbers of positive cholangiograms. Of the 64 patients having a laparoscopic common bile duct exploration (LCBDE), four (6%) required endoscopic retrograde cholangiopancreatography (ERCP) for retained stones (94% successful surgical clearance of the common bile duct) and one (2%) for a bile leak. Of the 335 patients undergoing LC alone, three (0.9%) re-presented with a retained stone, requiring intervention. There were 12 (7%) requiring conversion to open operation.

CONCLUSIONS

A selective policy for intra-operative cholangiography yields acceptably high positive results. Pre-operatively, asymptomatic bile duct stones rarely present following LC; thus, routine imaging of the biliary tree for occult calculi can safely be avoided. Therefore, a rationing approach to the use of intra-operative imaging based on the pre-operative indicators presented in this paper, successfully identifies those patients with bile duct stones requiring exploration. Laparoscopic bile duct exploration, performed by an experienced laparoscopic surgeon, is a safe and effective method of clearing the bile duct of calculi, with minimal complications, avoiding the necessity for an additional intervention and prolonged hospital stay.

Is ERCP really necessary in case of suspected spontaneous passage of bile duct stones?

AIM: To investigate the usefulness of magnetic resonance cholangiopancreatography (MRCP) and the need for endoscopic retrograde cholangiopancreatography (ERCP) in cases of suspected spontaneous passage of stones into the common bile duct.

METHODS: Thirty-six patients with gallbladder stones were clinically suspected of spontaneous passage of stones into the common bile duct because they presented with clinical symptoms such as abdominal pain and fever, and showed signs of inflammatory reaction and marked rise of hepatobiliary enzymes. These symptoms resolved and they showed normalized values of blood biochemical parameters after conservative treatment without evidence of stones in the common bile duct on MRCP. All these patients were subjected to ERCP within 3 d of MRCP to check for the presence of stones.

RESULTS: No stones were detected by ERCP in any patient, confirming the results of MRCP.

CONCLUSION: When clinical symptoms improve, blood biochemical parameters have normalized, and MRCP shows there are no stones in the common bile duct, it can be considered the stone has spontaneously passed and thus ERCP is not necessary.

Hospital cost categories of one-stage versus two-stage management of common bile duct stones

BACKGROUND

In the era of cost-conscious healthcare, hospitals are focusing on costs. Analysis of hospital costs per cost category may provide indications for potential cost-saving measures in the management of common bile duct stones (CBDS) with gallbladder in situ.

METHODS

Between October 2005 and September 2006, 53 consecutive patients suffering from CBDS underwent either a one-stage procedure [laparoscopic common bile duct exploration (LCBDE) with stone clearance and cholecystectomy (LCCE)] or a two-stage procedure [endoscopic retrograde cholangiopancreatography with sphincterotomy and stone clearance (ERCP/ERS) followed by LCCE]. Costs were defined in different cost categories for each activity centre and were linked to the individual patient via the "bill of activities". Only patients (n = 38) with an uneventful post-procedural course and with available cost data were considered for cost analysis. Total length of hospital stay (LOS) was 2 (0-6) days after one-stage and 8 (3-18) days after two-stage procedure (p < 0.0001).

RESULTS

Costs per patient were significantly (p < 0.0001) less after one-stage versus two-stage management, i.e. total hospital costs (euro2,636 versus euro4,608), hospitalisation costs (euro701 versus euro2,190), consumables/pharmacy (euro645 versus euro1,476) and para-medical personnel (euro1,035 versus euro1,860; p = 0.0002). Operation room (OR) costs were comparable for one-stage and two-stage management (euro1,278 versus euro1,232; p = 0.280). Total hospital costs during ERCP were euro2,648 (euro729-4,544), during LCCE without LCBDE were euro2,101 (euro1,033-4,269), and during LCCE with LCBDE were euro2,636 (euro1,176-4,235).

CONCLUSION

In the management of patients with CBDS and gallbladder in situ a one-stage procedure is associated with significantly less costs as compared with a two-stage procedure. From the economical point of view these patients should preferably be treated via a one-stage procedure as long as safety and efficacy of this approach are provided.

Acute biliary pancreatitis: detection of common bile duct stones with endoscopic ultrasound

OBJECTIVES

To determine prospectively the sensitivity and specificity of endoscopic ultrasound (EUS) for detecting common bile duct stones (CBS) in patients with acute biliary pancreatitis in whom transabdominal ultrasound was negative for CBS.

METHODS

In 38 consecutive patients with acute biliary pancreatitis who were negative for CBS by transabdominal ultrasound, EUS was performed before endoscopic retrograde cholangiopancreatography (ERCP). The endoscopist performing ERCP was blind to the results of EUS. The primary goal of EUS and ERCP was to confirm or exclude CBS. The reference standard for CBS was endoscopic extraction of bile duct stones after endoscopic sphincterotomy. When both procedures, EUS and ERCP excluded CBS, it was assumed that there were no CBS and endoscopic sphincterotomy was not performed. The results EUS and ERCP were compared with the McNemar test.

RESULTS

Twenty-five of the 38 patients (66%) had CBS. EUS and ERCP were false negative in one patient each, EUS was false positive in two patients and ERCP in one patient. The sensitivity of both EUS and ERCP was 96%. The specificity of EUS and ERCP was 85 and 92%, respectively. The difference between EUS and ERCP was not significant (P=0.9).

CONCLUSION

EUS proved to be as sensitive as ERCP for detection of CBS in patients with acute biliary pancreatitis. Therefore, EUS could be used as the first-line procedure in patients with acute biliary pancreatitis when therapeutic ERCP is not needed. By this approach a substantial number of unnecessary diagnostic ERCP procedures could be avoided.

The role of MR cholangiopancreatography in the evaluation of pregnant patients with acute pancreaticobiliary disease

This study aimed to determine the usefulness of MR cholangiopancreatography (MRCP) in the evaluation of pregnant patients with acute pancreaticobiliary disease and its additional value over ultrasound. MRI studies of pregnant patients who were referred because of acute pancreaticobiliary disease were included. MR images and patient charts were reviewed retrospectively to determine clinical outcome and the results of other imaging studies. 18 pregnant patients underwent MRCP because of right upper quadrant pain (n = 6), pancreatitis (n = 9), cholangitis (n = 1) or jaundice (n = 2). 15 patients were also evaluated with ultrasound. Biliary dilatation was detected in eight patients by ultrasound, but the cause of biliary dilatation could not be determined by ultrasound in seven patients. MRCP demonstrated the aetiology in four of these patients (choledocholithiasis (n = 1), Mirizzi syndrome (n = 1), choledochal cyst (n = 1) and intrahepatic biliary stones (n = 1)) and excluded obstructive pathology in the other four patients. MRCP was unremarkable in the seven patients who had no biliary dilatation on ultrasound. Three patients underwent only MRCP; two had choledocholithiasis and one cholelithiasis and pancreatitis. Choledocholithiasis diagnosed with MRCP (n = 3) was confirmed by endoscopic retrograde cholangiopancreatography. Mirizzi syndrome (n = 1) and a choledochal cyst (n = 1) were confirmed by surgery. The patients with normal MRCP (n = 12) and one patient with intrahepatic stones improved with medical treatment. MRCP appears to be a valuable and safe technique for the evaluation of pregnant patients with acute pancreaticobiliary disease. Especially when ultrasound shows biliary dilatation, MRCP can determine the aetiology and save the patient from unnecessary endoscopic retrograde cholangiopancreatography by excluding a biliary pathology.

Diagnostic value of magnetic resonance cholangiopancreatography for clinically suspicious spontaneous passage of bile duct stones

BACKGROUND AND AIM

We investigated the usefulness of magnetic resonance cholangiopancreatography (MRCP) and the need for endoscopic retrograde cholangiopancreatography (ERCP) in patients with clinically suspicious spontaneous passage of bile duct stones.

METHODS

The study population consisted of 113 patients suspected of having common duct bile stones. Of them, 50 patients were clinically suspected of spontaneous passage of bile duct stones based on the presence of gallbladder stones on ultrasound examination or a history of common bile duct stones after cholecystectomy, clinical symptoms including abdominal pain and fever associated with inflammatory reaction and marked rise of hepatobiliary enzymes which resolved or normalized after conservative treatment without evidence of stones in the common bile duct on MRCP. These 50 patients were prospectively followed up for a median of 10.2 months.

RESULTS

All patients except for one had had no symptoms related to cholangitis. Only one patient received ERCP due to recurrence of symptoms after 6 months.

CONCLUSION

When clinical symptoms improve, hematological parameters normalize, and MRCP indicates that there are no stones in the common bile duct, it can be considered that the stones have passed naturally.

Assessment of the main pancreatic duct using computed tomography with multiplanar reconstructions

The aim of this study was to assess the morphology of the main pancreatic duct (MPD) using multiplanar reconstructions and to compare this with the morphology of the MPD of anatomic subjects.

MATERIALS AND METHODS

The morphology of the MPD was studied by means of multiplanar reconstructions obtained on the one hand from thin tomodensitometric slices and on the other hand from the dissection of anatomic subjects. This study involved 15 subjects in each group.

RESULTS

Full multiplanar reconstruction was obtained in 13 cases. In 2 cases, the isthmus did not appear in the reconstructions. The morphology of the MPD was similar in both groups. The length of the MPD was identical at the head and isthmus of the pancreas in both groups but was greater in the dissection group than in the reconstruction group in the body and tail areas of the pancreas. The diameter of the MPD was greater at the head of the pancreas in the dissection group and was identical in both groups for the other segments of the MPD.

CONCLUSIONS

Multiplanar tomodensitometric reconstruction of the main pancreatic duct is feasible. This new technique, currently under evaluation, could allow the study of canalar pathologies of the pancreas through tomodensitometry.

Impact of the operator's experience on value of high-resolution transabdominal ultrasound in the diagnosis of choledocholithiasis: a prospective comparison using endoscopic retrograde cholangiography as the gold standard

OBJECTIVE

Transabdominal ultrasound (US) is the most frequently used imaging method for the diagnosis of choledocholithiasis. The aim of this prospective study was to evaluate the diagnostic accuracy of high-resolution US in the diagnosis of common bile duct stones depending on the operator's experience and in comparison with endoscopic retrograde cholangiography (ERC) as the gold standard.

MATERIAL AND METHODS

From April 2003 through November 2004, 126 patients referred because of clinically and biochemically suspected common bile duct stones were included in the study. Two patients were excluded because they refused to undergo ERC. Consequently, the study comprised 124 patients (86 F, 38 M, mean age 63.2 years, range 21-91 years). High-resolution US was performed (2-5 MHz sector scanner; Siemens Elegra, Erlangen, Germany) by operators who were unaware of the results of other imaging procedures. The definitive diagnosis was established by means of ERC.

RESULTS

Thirty-five out of 124 patients were investigated by experienced examiners. Twenty-seven of 35 patients (77%) were found to have stones at ERC. Bile duct stones were correctly found by US in 22 out of 27 patients (sensitivity 82%, 95% CI: 63-92). Of the 8 patients without stones at ERC, one false-positive diagnosis was made with US (specificity 88%, 95% CI: 53-98). Correct diagnoses were made in 29 out of 35 (accuracy 83%, 95% CI: 67-92) patients investigated by experienced examiners. Eighty-nine out of 124 patients were investigated by less-experienced examiners. Fifty-four of 89 patients (61%) were found to have stones at ERC. Choledocholithiasis was found correctly in only 25 out of 54 patients (sensitivity 46%, 95% CI: 34-59). Of the 35 patients without stones at ERC, three false-positive diagnoses were made with US (specificity 91%, 95% CI: 78-97). In conclusion, correct diagnoses were observed in 57 of 89 patients (accuracy 64%, 95% CI: 54-73) investigated by less-experienced examiners (p<0.05 in comparison with the results of experienced examiners).

CONCLUSIONS

High-resolution US carried out by experienced examiners has a high diagnostic accuracy in the diagnosis of choledocholithiasis. Therefore, good training and continued experience are prerequisites for successful sonographic detection of bile duct stones using US. Under these conditions, further expensive and invasive methods such as ERC, magnetic resonance cholangiopancreatography and endoscopic ultrasonography may not be necessary in cases with a clear sonographic diagnosis.

3.0- Versus 1.5-T MR Cholangiography: A Pilot Study

OBJECTIVE

The purpose of our study was to evaluate quantitative and qualitative image quality of MR cholangiography at a field strength of 3.0 T compared with the standard field strength of 1.5 T.

MATERIALS AND METHODS

A standardized MR cholangiography sequence protocol was used for 15 healthy male volunteers (mean age +/- SD, 32.4 +/- 4.3 years) who underwent both 1.5- and 3.0-T MRI within 2 hr in an alternating fashion. Dedicated circular polarized torso coils (1.5 and 3.0 T) were used. The sequence protocol included breath-hold single-slice rapid acquisition with relaxation enhancement (slice thickness, 50 mm; orientation, coronal and +/- 20 degrees oblique coronal); breath-hold multislice HASTE (slice thickness, 3 mm; coronal only); and a non-breath-hold, respiratory-triggered 3D turbo spin-echo (TSE) T2-weighted sequence (slice thickness, 1 mm; 60 slices per slab; coronal only). Maximum intensity projections were generated from each multislice data set. Bile duct (common bile duct, right posterior segmental branch, and left hepatic duct) to periductal tissue contrast-to-noise ratios were compared at 1.5 and 3.0 T. Qualitative image analysis was performed by three independent reviewers. Qualitative analysis included delineation of the extra- and intrahepatic biliary anatomy, with specific attention given to the presence (or absence) of cystic or intrahepatic ductal variants, using a 4-point confidence scale. Statistical analysis consisted of the paired Student's t test and the signed rank test.

RESULTS

Contrast-to-noise ratios between the bile duct and the periductal tissue were higher at 3.0 T in all three locations (common bile duct, right posterior segmental branch, and left hepatic duct). In each magnet class, the 3D TSE sequence offered the best contrast-to-noise ratio and qualitative analysis. Superiority of the 3D TSE sequence was statistically significant in all analyses. Five of the 15 volunteers had intrahepatic biliary variants that were detected with a higher level of confidence (p < 0.01) on the 3.0-T system than on the 1.5-T system.

CONCLUSION

Compared with MR cholangiography at 1.5 T, MR cholangiography at 3.0 T offers improved contrast-to-noise ratio and a higher level of confidence for depicting intrahepatic variants.

Limitations of fluoroscopic intraoperative cholangiography in cases suggestive of choledocholithiasis

BACKGROUND

Fluoroscopic intraoperative cholangiography (IOC) has been proposed as a safe and accurate screening method for choledocholithiasis, with a sensitivity and specificity of nearly 100% in selected cases. In the present study we retrospectively reviewed the diagnostic accuracy of IOC in cases highly suggestive of choledocholithiasis.

MATERIALS AND METHODS

Between January 1999 and December 2002, 103 patients underwent IOC as an imaging method for common bile duct (CBD) stone detection. We did not routinely perform IOC in all patients who were submitted to laparoscopic cholecystectomy, reserving the method for patients with a high probability of choledocholithiasis, namely patients with a history or the presence of painful obstructive jaundice at the time of referral, patients with a history of mild acute pancreatitis of biliary origin, and patients with abnormalities in their liver biochemistry profile as measured by liver function tests (LFT).

RESULTS

The mean rates of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for IOC were 98%, 94%, 94.5%, and 98% for the whole series, respectively. The diagnostic accuracy was 100% in patients with a history of obstructive jaundice or liver biochemical derangement, but was less in patients with a history of biliary pancreatitis. There were 3 false positive cases and 1 case of false negative results, all of which occurred in the subgroup of patients with a history of pancreatitis.

CONCLUSION

Selective fluoroscopic IOC is generally feasible and safe, as well as highly accurate (100%) for CBD stone detection in patients with obstructive jaundice or abnormal LFT. The PPV of the method decreases in patients with a history of pancreatitis (75%), while a negative result is highly suggestive of the absence of CBD stones (NPV = 98%). The present study concluded in a higher incidence of false results in patients with a normal size CBD, suggesting that the diagnostic accuracy of IOC is probably related to the size of the CBD rather than the indication for its performance.

Imaging patients with "post-cholecystectomy syndrome": an algorithmic approach

AIM

To assess the role of ultrasound (US), magnetic resonance cholangiopancreatography (MRCP) and liver function tests (LFTs) in the evaluation of selected patients presenting with late post-cholecystectomy syndrome (PCS) who were referred for endoscopic retrograde cholangiopancreatography (ERCP).

MATERIALS AND METHODS

In a retrospective study a final group of 42 patients with PCS referred for diagnostic ERCP underwent MRCP and abdominal US. ERCP and MRCP images were assessed for bile duct diameters and the presence of strictures and stones. A common bile duct (CBD) diameter of < 10mm was considered normal, whereas > or = 10mm was considered abnormal on US. Findings were correlated to LFTs with contingency table results performed for single techniques and combination of methods.

RESULTS

In total 14 stones and one stricture were seen. US had a high negative predictive value (86.4%). MRCP had a sensitivity of 100% and specificity of 88.0%. ERCP is the most accurate test but failed in 11 patients, five of whom had a stone. The accuracy of US and LFTs increases to 93.8% if test results agree in either negative or positive outcome.

CONCLUSION

US and LFTs are first-line tests in PCS. If the CBD on US is > or = 10mm, but no cause is identified, MRCP should be performed. If US and LFTs are normal then MRCP is not necessary. The availability of LFTs raises the diagnostic value of imaging.

Accuracy of computed tomographic intravenous cholangiography (CT-IVC) with iotroxate in the detection of choledocholithiasis

To determine the accuracy of computed tomographic intravenous cholangiography (CT-IVC) for detection of choledocholithiasis. Sixty-five patients undergoing endoscopic retrograde cholangiography (ERC) underwent CT-IVC prior to ERC, using a single detector helical CT following intravenous infusion of 100 ml iotroxate. Patients with bilirubin levels >3 times normal were excluded. ERC was indeterminate in three patients (4.7%) and CT-IVC in four (6.3%). Twenty-three patients had ductal calculi at ERC, and CT-IVC was positive in 22, with two false positives and one false negative: sensitivity 95.6%, specificity 94.3%. Stones were multiple in nine and solitary in 14. Of the 14 solitary stones, ten were <or=5 mm and eight were <or=4 mm. The bilirubin level in positive cases was within normal in 20. Maximum intensity projection (MIP) reformats showed stones in only 27% of cases and surface rendered (SR) reformats in none. CT-IVC is highly accurate for detection of ductal calculi, including single small calculi, with a normal or near normal serum bilirubin. Axial images should be used for interpretation rather than MIP or SR reformats.

Magnetic resonance cholangiography: applications in patients with calculus disease of the biliary tract

Magnetic resonance cholangiography (MRC) is a non-invasive imaging modality that has become widely available. In the short time since its introduction, MRC has been shown to possess excellent accuracy for the diagnosis of various biliary pathologies, including choledocholithiasis. Investigations of the clinical applications of MRC are ongoing. This review summarizes the diagnostic capabilities of MRC and discusses its application in the management of patients with gallstone diseases.

La cholangio-IRM dans le diagnostic étiologique des sténoses biliaires : corrélation anatomopathologique

OBJECTIVE

To evaluate the accuracy of MR cholangiography to differentiate between the benign and malignant etiology of biliary strictures, excluding bilioenteric anastomoses.

MATERIALS AND METHODS

49 patients (26 males, 23 females) with suspected biliary stricture underwent MR cholangiography at 1.5T (Siemens Symphony). RARE and HASTE sequences were acquired in the coronal, oblique and axial planes. MR cholangiography findings were reviewed by two independent radiologists and correlated with the final histological diagnosis. Sensitivity, specificity, and agreement were calculated with a 95% confidence interval.

RESULTS

Benign stenosis was identified in 23 patients (47%) and malignant stenosis in 26 (53%). The sensitivity of MR cholangiography was 64% and the specificity was 96%. The agreement between results at MR cholangiography and histology was moderate. The inter-observer agreement for MR cholangiography was good with a Kappa value of 0.61.

CONCLUSION

MR cholangiography has the potential to replace diagnostic cholangiography in patients with suspected biliary stricture. Direct cholangiography could be reserved for patients where a therapeutic procedure is anticipated.

MR imaging in abdominal emergencies

The use of MR imaging in the emergency setting is evolving. Clear indications include situations in need of contrast media when iodinated contrast cannot be administered or to facilitate assessments in pregnant patients and children when exposure to ionizing radiation is considered unacceptable. The availability of rapid, motion-immune sequences now makes MR imaging a feasible study in less cooperative patients extending the range of patients for whom a diagnostic study can be achieved. Capitalizing on the unique benefits of MR imaging there is optimism that MR imaging can eliminate test redundancy and impact patient care in a cost-effective manner. Further investigations are needed to identify the diagnostic algorithms for which this favorable use holds true.

Research misconduct

Good research practice is important to the scientific community. An awareness of what constitutes poor practice is important. Various types of research misconduct are defined in this article. The extent of research misconduct in the field of radiology has been assessed by contacting five English language radiology journals. Redundant or duplicate publication has been reported infrequently, Radiology (1), American Journal of Roentgenology (3), Clinical Radiology (3), British Journal of Radiology (2) and European Radiology (1). The issue of how the radiology community might tackle research misconduct is discussed with reference to guidance from the Medical Research Council, the Wellcome Trust and the Committee of Publication Ethics.

Value of magnetic resonance cholangiography in benign and malignant biliary stenosis: comparative study with direct cholangiography

PURPOSE

Magnetic resonance cholangiography (MRC) is currently under investigation for imaging of biliary stenosis. The purpose of this study was to evaluate the diagnostic value of MRC compared with direct cholangiography in biliary duct diseases, with the exception of biliary-enteric anastomosis.

METHOD

Forty-nine patients (26 men, 23 women; median age 60 years) with clinically suspected bile duct stenosis were prospectively included. Magnetic resonance cholangiography was performed within 7 days before direct cholangiography, considered to be the gold standard. Stenosis location, extension, and type according to Bismuth classification as well as diagnostic presumed causes were determined by 2 radiologists and 1 endoscopist.

RESULTS

Magnetic resonance cholangiography correctly identified the level of biliary ductal obstruction compared with direct cholangiography findings in 96% patients. Excellent agreement between MRC and direct cholangiography was found for the stenosis location (kappa value, 0.89). Sensitivity and specificity of MRC to detect common bile duct stenosis were 88% and 100%, respectively. Sensitivity and specificity of MRC to detect biliary confluence stenosis were 96% and 93%, respectively. Precise location of the lesion according to Bismuth classification was correctly evaluated on MRC in 74% of patients (kappa value, 0.64). The overall interobserver concordance between radiologists for the level of stenosis was good (kappa value, 0.625). In 35 patients with intrahepatic bile ducts dilation identified on direct cholangiography, 97% of patients were identified on MRC. Moderate concordance between MRC and direct cholangiography was confirmed in the evaluation of the surgical management (kappa value, 0.55).

CONCLUSION

Magnetic resonance cholangiography is able to replace diagnostic direct cholangiography to restrict the use of invasive procedures to cases in which therapeutic procedures are anticipated or MRC findings are equivocal, especially in biliary tract diseases.

The role of ultrasound in biliary and pancreatic diseases

The possibilities and the limits of transabdominal ultrasonography (US) in the diagnosis of bilio-pancreatic diseases are reviewed here in the light of the last 10 years' research. US remains the method of choice for the diagnosis of gallstones and is generally accepted as an initial imaging technique in gallstone complications, such as acute cholecystitis. Moreover the method can be useful for the detection of the biliary complications after laparoscopic cholecystectomy and after liver transplantation. US is still considered the first diagnostic procedure when stones are suspected in the common bile duct. The use of color Doppler can provide a differential diagnosis of gallbladder cancer with respect to other benign inflammatory or polypoid lesions. Color Doppler US allows to detect vascular complications of acute pancreatitis such as pseudoaneurysms. US is still considered useful for the initial screening of the pancreatic cancer. However, for staging other imaging techniques must be employed. With US useful informations are obtained in the diagnosis of cystic tumors of the pancreas and of pancreatic metastases. US is generally of little use for the diagnosis of endocrine tumors.

The value of magnetic resonance cholangiopancreatography in predicting common bile duct stones in patients with gallstone disease

BACKGROUND

The application of available predictive scoring systems for the detection of common bile duct (CBD) stones has not reduced the number of patients who undergo unnecessary endoscopic retrograde cholangiopancreatography. The aim of this study was to create a predictive model for CBD stones and to assess the value of magnetic resonance cholangiopancreatography (MRCP) in prediction.

METHODS

In 1998, 366 patients with gallstone disease (118 males, 248 females; mean age 57 (range 8-84) years) underwent cholecystectomy. Statistical analysis was performed on patient data obtained at the time of first presentation.

RESULTS

CBD stones were demonstrated in 43 (12 per cent) of 366 patients. The predictive model for common duct stones included ultrasonography showing CBD stones or bile duct dilatation, age greater than 60 years, fever, serum alkaline phosphatase level above 670 units/l and serum amylase level above 95 units/l. In patients with a predicted probability greater than 5 per cent, CBD stones were present in 11 per cent, compared with 1 per cent in patients with a probability of 5 per cent or less. MRCP had an observed sensitivity of 95 per cent, specificity of 100 per cent, positive predictive value of 100 per cent and negative predictive value of 98 per cent.

CONCLUSION

In patients with a predicted probability for CBD stones of more than 5 per cent, MRCP is recommended in order to confirm the presence or absence of stones and as guidance in further management.

Update on magnetic resonance cholangiopancreatography

MRCP is a useful tool in the diagnosis of a wide variety of pathologic entities including congenital anomalies, biliary obstruction and stricture, biliary calculi, pancreatitis, neoplasms, and trauma. ERCP and MRCP both have important roles in the management of patients with suspected pancreaticobiliary disease. Knowledge of the advantages and disadvantages of each technique is needed to determine the appropriate work-up of patients with these pathologies.

Prospective assessment of magnetic resonance cholangiopancreatography for noninvasive imaging of the biliary tree

BACKGROUND

Traditionally, ERCP has been the only reliable method for imaging the biliary tree, but it is invasive and carries a risk of complications. Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive method for imaging the biliary tree. The aim of this study was to prospectively assess the accuracy of MRCP in a large number of patients.

METHODS

Consecutive patients referred to a teaching hospital for ERCP were eligible for study entry. MRCP was performed within 24 hours before ERCP. MRCP findings were compared with ERCP findings or, when the initial ERCP was unsuccessful, with results of repeat ERCP, percutaneous transhepatic cholangiography, or surgery.

RESULTS

One hundred forty-six patients underwent 149 ERCP/MRCP procedures, of which 129 were evaluable with successful MRCP and ERCP or an ERCP-equivalent study. Diagnoses included choledocholithiasis in 46 and biliary stricture in 12 patients. The sensitivity, specificity, positive, and negative predictive values for MRCP in the diagnosis of choledocholithiasis were 97.9%, 89.0%, 83.6%, and 98.6%, respectively. All 12 strictures were diagnosed by MRCP (sensitivity 100%, specificity 99.1%).

CONCLUSIONS

MRCP is an accurate, noninvasive alternative to ERCP for imaging the biliary tree. Choledocholithiasis and biliary strictures can be reliably diagnosed or excluded by MRCP. MRCP should be used increasingly in patients with suspected biliary obstruction to select those who require a therapeutic procedure.

MR and ultrasound in screening of patients with suspected biliary tract disease

PURPOSE

The diagnostic value and cost-efficiency of MR imaging were compared with US before endoscopic retrograde cholangiopancreatography (ERCP) in patients with clinically suspected biliary tract disease.

MATERIAL AND METHODS

In a prospective study of 219 patients, 85 were examined with both MR and US before ERCP.

RESULTS

To find the correct diagnosis in the jaundiced patients the sensitivity of US, MR and ERCP was 53%, 93%, and 89%, respectively. In the patients with abdominal upper quadrant pain and normal serum bilirubin, the sensitivity of US, MR and ERCP was 50%, 100% and 70%, respectively. Examination with MR costs four times more than US. Screening with US and supplemental MR in non-diagnostic cases would cost 80% of the total amount compared to screening with MR only.

CONCLUSION

MR had a higher sensitivity than US for diagnosing biliary tract disease and MR was superior to US in visualising stones in the common bile duct and in diagnosing the cause of cholestasis. However, screening with US and supplemental MR in non-diagnostic cases is at present most cost-effective. With increased accessibility and slightly lower costs, MR will probably replace US as screening method in patients with suspected biliary tract disease.

Recurrent Acute Pancreatitis

Patients with recurrent acute pancreatitis should be treated with the same supportive and symptom-oriented measures as those with acute pancreatitis. The need for specific treatment depends on the cause of the pancreatitis. Patients should discontinue alcohol use, putative causative medications, and exposure to toxins or helminths in endemic areas. Metabolic abnormalities need to be corrected, and appropriate treatment should be initiated for associated infections, autoimmune diseases, vasculitis, and hypercoagulable states. For patients with gallstone pancreatitis, endoscopic retrograde cholangiopancreatography is indicated if biliary obstruction persists or if cholangitis is present. Elective cholecystectomy may be performed in appropriate patients; otherwise, consider biliary sphincterotomy and ursodeoxycholic acid for prevention of recurrent attacks. Transpapillary stenting or sphincterotomy of the minor papilla benefits some patients with pancreas divisum and no other explanation for recurrent pancreatitis. Surgical sphincteroplasty is reserved for those failing endoscopic treatment. Biliary sphincterotomy benefits more than 50% of patients with sphincter of Oddi dysfunction and recurrent acute pancreatitis. Some authors advocate pancreatic sphincter manometry and sphincterotomy for persistent pancreatic segment hypertension in patients who have recurrent pancreatitis after biliary sphincterotomy. In patients with pancreatic duct strictures, transpapillary stent placement serves as a short-term measure; most patients ultimately require surgery.

Detection of choledocholithiasis by EUS in acute pancreatitis: a prospective evaluation in 100 consecutive patients

BACKGROUND

ERCP is the standard for detection of choledocholithiasis in patients with acute biliary pancreatitis, and, if performed early, ERCP decreases morbidity. However, there are procedure-related complications. The aim of the present prospective study was to evaluate the ability of EUS to detect choledocholithiasis in patients presenting with acute pancreatitis.

METHODS

The study group comprised 100 consecutive patients who presented with acute pancreatitis. EUS, and immediately thereafter, ERCP were performed by separate blinded examiners within 24 hours of admission. The diagnostic accuracy of EUS in identifying gallbladder stones was compared with that of transcutaneous US. The diagnostic accuracy of EUS in detecting choledocholithiasis was then compared with that of US and ERCP based on the results of endoscopic instrumentation of the bile duct after sphincterotomy.

RESULTS

EUS was more sensitive than US in detecting gallbladder stones (100% vs. 84%, p < 0.005). The sensitivities of ERCP and EUS for choledocholithiasis were both 97%, and the overall accuracies were 96% and 98%, respectively, with no significant difference. EUS detected the absence of choledocholithiasis in 65 of 66 patients (specificity = 98%). Endosonographic examination was successful in all patients, whereas ERCP was unsuccessful in 5 patients (p > 0.05). Post-endoscopic sphincterotomy bleeding developed in 4 patients; there was no EUS-related morbidity (p > 0.05).

CONCLUSION

EUS is more sensitive than US in detecting biliary stones in patients with acute pancreatitis. It is as accurate as ERCP in detecting choledocholithiasis. EUS can be used to select patients with acute pancreatitis who require therapeutic ERCP, thus avoiding diagnostic ERCP and its associated potential for complications in the majority of patients.

Prospective randomized double-blind placebo-controlled trial of glyceryl trinitrate in endoscopic retrograde cholangiopancreatography-induced pancreatitis

BACKGROUND

One possible aetiology of pancreatitis following endoscopic retrograde cholangio pancreatography (ERCP) is cannulation-induced spasm of the sphincter of Oddi and consequent pancreatic duct obstruction. Sublingual glyceryl trinitrate (GTN) has been shown to produce periampullary sphincter relaxation. The aim of this study was to determine whether prophylactic long-acting GTN could reduce the incidence of ERCP-induced pancreatitis.

METHODS

In a randomized double-blind study, prophylactic treatment with GTN (2 mg given sublingually 5 min before endoscopy) was compared with placebo in 186 patients who presented for elective ERCP. The primary endpoint was the occurrence of pancreatitis within 24 h, defined as a serum amylase concentration greater than 1000 units/ml in association with a visual analogue pain score of more than 5.

RESULTS

The incidence of pancreatitis was lower in the GTN group compared with placebo (seven of 90 versus 17 of 96; P < 0.05). Mean serum amylase values were similar in the two groups. The protective effect of GTN appears to be highest in the diagnostic ERCP group (one of 54 versus ten of 66; P = 0.012) and in the group in which cholangiography alone was performed (one of 54 versus eight of 57; P = 0.032).

CONCLUSION

Prophylactic treatment with GTN reduces the incidence of pancreatitis following ERCP but does not seem to reduce the extent of hyperamylasaemia or the severity of pancreatitis.

Pancreatic ultrasonography

Pancreatic abnormalities usually are detected on US when it is used for screening patients with abdominal pain and for assessment of the gallbladder and bile ducts. Pancreatic visualization is limited by bowel gas, but with experienced sonographers and newer techniques, including harmonic imaging and oral contrast US, diagnosis of pancreatic abnormalities has significantly improved compared with earlier reports. Appropriate initial diagnosis by US can tailor further investigation, and US-guided biopsy may establish definitive diagnosis.

Recurrent acute pancreatitis: an algorithmic approach to identification and elimination of inciting factors

Recurrent acute pancreatitis represents a challenging clinical problem associated with significant morbidity, impairment in quality of life, and expense. If unchecked, recurrent episodes of acute pancreatitis may lead to chronic pancreatitis. In this work we have combined the opinion of experts in pancreatology and an extensive review of the literature to develop a logical algorithm that facilitates the stepwise identification and elimination of inciting factors using current technology. The approach taken in recurrent acute pancreatitis is clearly dependent on adequate and appropriate evaluation and treatment of the patient with an initial episode of acute pancreatitis. Future advances in the treatment of these patients will almost certainly depend on improved imaging modalities, prospective clinical trials assessing the efficacy of endoscopic and surgical intervention, a better understanding of mutations and pathophysiologic mechanisms responsible for recurrent acute pancreatitis, and the development of novel, effective preventive and therapeutic strategies.