Common bile duct stones on multidetector computed tomography: Attenuation patterns and detectability

Measurement of the distal bile duct density on computed tomography can differentiate choledocholithiasis from a control population

PURPOSE

Hounsfield unit density of biliary fluid on CT may be a useful clinical marker that has not been described in the literature. This method has been used to differentiate pyonephrosis from hydronephrosis in obstructed collecting systems of the kidney. We aimed to create a user-friendly technique to measure the density of the distal bile duct using CT. The bile duct density of cases with proven choledocholithiasis at ERCP were compared with those of a control group (no biliary pathology).

METHODS

A total of 106 patients with proven choledocholithiasis at ERCP and 50 control patients were analysed. The distal bile duct density was calculated using the 4-point and max ellipse methods. Two blinded, independent investigators calculated the bile duct density.

RESULTS

The HU is significantly higher in the presence of choledocholithiasis (P < 0.0001). Using the Youden index a cut-off value of 28.6 HU for the 4-point technique is useful to predict the presence of choledocholithiasis (Sensitivity 58%, Specificity 86%).

CONCLUSION

Calculation of the distal bile duct density can differentiate choledocholithiasis from a control population. It may be useful alone or as a component of a scoring system to select patients more effectively for intervention. The improved use of CT may also decrease use of MRCP and reduce time to ERCP, which have potential cost benefits.

CT Evaluation of Long-Term Changes in Common Bile Duct Diameter after Cholecystectomy

Purpose

The present study aimed to investigate the frequency and extent of compensatory common bile duct (CBD) dilatation after cholecystectomy, assess the time between cholecystectomy and CBD dilatation, and identify potentially useful CT findings suggestive of obstructive CBD dilatation.

Materials and Methods

This retrospective study included 121 patients without biliary obstruction who underwent multiple CT scans before and after cholecystectomy at a single center between 2009 and 2011. The maximum short-axis diameters of the CBD and intrahepatic duct (IHD) were measured on each CT scan. In addition, the clinical and CT findings of 11 patients who were initially excluded from the study because of CBD stones or periampullary tumors were examined to identify distinguishing features between obstructive and non-obstructive CBD dilatation after cholecystectomy.

Results

The mean (standard deviation) short-axis maximum CBD diameter of 121 patients was 5.6 (± 1.9) mm in the axial plane before cholecystectomy but increased to 7.9 (± 2.6) mm after cholecystectomy (p < 0.001). Of the 106 patients with a pre-cholecystectomy axial CBD diameter of < 8 mm, 39 (36.8%) showed CBD dilatation of ≥ 8 mm after cholecystectomy. Six of the 17 patients with longterm (> 2 years) serial follow-up CT scans (35.3%) eventually showed a significant (> 1.5-fold) increase in the axial CBD diameter, all within two years after cholecystectomy. Of the 121 patients without obstruction or related symptoms, only one patient (0.1%) showed IHD dilatation > 3 mm after cholecystectomy. In contrast, all 11 patients with CBD obstruction had abdominal pain and abnormal laboratory indices, and 81.8% (9/11) had significant dilatation of the IHD and CBD.

Conclusion

Compensatory non-obstructive CBD dilatation commonly occurs after cholecystectomy to a similar extent as obstructive dilatation. However, the presence of relevant symptoms, significant IHD dilatation, or further CBD dilatation 2-3 years after cholecystectomy should raise suspicion of CBD obstruction.

CT of appendicoliths in adult appendicitis: clinical significance and characteristics of overlooked cases

OBJECTIVES

Accurate computed tomography (CT) identification of appendicoliths in adults with acute appendicitis is crucial as it may preclude nonoperative management due to high risk of failure and complications. This investigation aimed to identify the significance of appendicoliths in acute appendicitis and to evaluate the performance of portovenous-phase (PVP) CT and the consequences of overlooked appendicoliths.

METHODS

CT examinations of 324 consecutive patients (mean age 51.9 years, 112 men) with pathologically confirmed acute appendicitis were retrospectively included. Two radiologists independently reviewed the images, and disagreement was resolved by a consensus.

RESULTS

Appendicoliths were identified in 134/324 patients, of which 75 had complicated appendicitis. Among 190 patients without appendicoliths, 52 had complicated appendicitis. An appendicolith was independently associated with complicated appendicitis (adjusted odds ratio 2.289; 95% CI: 1.343-3.902; p = 0.002). The larger minimum diameter was significantly associated with complication. The 4.5-/6.0-mm cutoffs for minimum and maximum diameters of appendicoliths demonstrated 82.7%/85.3% sensitivity and 35.6%/33.9% specificity in predicting complications. The PVP alone had 82.1-88.1% sensitivity, respectively per patient and per appendicolith, and a 100% specificity in the detection of appendicoliths, as compared with combined noncontrast and PVP. PVP overlooked 28/237 appendicoliths (11.8%) corresponding to 24/134 patients (17.9%). Of the 24 patients with overlooked appendicoliths, 16 had complicated appendicitis but 14 were correctly categorized by findings other than appendicoliths. In total, 2/127 patients (1.6%) with complicated appendicitis were misdiagnosed as having uncomplicated appendicitis.

CONCLUSIONS

Appendicoliths in acute appendicitis were strongly associated with complications. While PVP overlooked some appendicoliths, only 1.6% of complicated appendicitis were misclassified when considering other CT findings.

CLINICAL RELEVANCE STATEMENT

This study found a strong association between appendicoliths and complications. Its presence may preclude conservative management. Although portovenous-phase CT overlooked some appendicoliths, the combination with other CT findings allowed correct classification in a vast majority of cases.

KEY POINTS

• Accurate identification of appendicoliths is crucial for nonoperative management decisions in adult acute appendicitis. • Appendicoliths are strongly associated with complications in adult acute appendicitis. • Portovenous-phase CT overlooked some appendicoliths, but only a small percentage of patients with complicated appendicitis were misclassified when considering other CT findings.

Predictors of technical success of percutaneous transhepatic common bile duct stone removal: is it only a matter of stone size?

OBJECTIVES

The common practice is to remove symptomatic common bile duct (CBD) stones in patients. This study aimed to investigate the factors affecting the percutaneous transhepatic removal of CBD stones.

METHODS

We retrospectively analyzed the data of 100 patients (66 men and 34 women; age: 25-105 years, mean 79.1 years) with symptomatic CBD stones who underwent percutaneous transhepatic stone removal (PTSR) from January 2010 through October 2019. After balloon dilation of the ampulla of Vater or bilioenteric anastomosis, the stones were pushed out of the CBD into the small bowel with a balloon catheter. If failed, basket lithotripsy was performed. Technical success was defined as complete clearance of the bile ducts on a cholangiogram.

RESULTS

The technical success rate was 83%, and achieved 90.2% in patients with altered gastroduodenal/pancreatobiliary anatomy. Multivariable analysis revealed that CBD diameter (odds ratio [OR]: 506.460, p = 0.015), failed ERCP (OR: 16.509, p = 0.004), Tokyo guidelines TG18/TG13 severity (grade III; OR: 60.467, p = 0.006), and left-sided transhepatic approach (OR: 21.621, p = 0.012) were risk factors for technical failure. The appropriate cutoff CBD size was 15.5 mm (area under the curve: 0.91). CBD stone size, radiopacity of stones, and CBD angle between retroduodenal and pancreatic portion did not influence technical success.

CONCLUSIONS

PTSR is effective for CBD stone removal in older adults and individuals with altered gastrointestinal tract anatomy. The aforementioned risk factors for technical failure should be considered in preoperative evaluation before PTSR to improve the success rate.

KEY POINTS

• PTSR is effective in symptomatic CBD stone management among older adults and individuals with altered anatomy. Investigating clinical /anatomic factors can guide radiologists toward a more comprehensive preoperative evaluation to maximize the success rate. • Our data indicate that dilated CBD (diameter ≥ 15.5 mm) and left-sided PTBDs reduce the technical success rate by 506-fold and 22-fold, respectively. • Clinical factors such as previous failed ERCP for stone removal and higher severity of acute cholangitis lessen the technical success rate.

Principles and Applications of Dual-Layer Spectral CT in Gastrointestinal Imaging

The advance in technology allows for the development of different CT scanners in the field of dual-energy computed tomography (DECT). In particular, a recently developed detector-based technology can collect data from different energy levels, thanks to its layers. The use of this system is suited for material decomposition with perfect spatial and temporal registration. Thanks to post-processing techniques, these scanners can generate conventional, material decomposition (including virtual non-contrast (VNC), iodine maps, Z-effective imaging, and uric acid pair images) and virtual monoenergetic images (VMIs). In recent years, different studies have been published regarding the use of DECT in clinical practice. On these bases, considering that different papers have been published using the DECT technology, a review regarding its clinical application can be useful. We focused on the usefulness of DECT technology in gastrointestinal imaging, where DECT plays an important role.

Do not get stumped: multimodality imaging findings of early and late post-cholecystectomy complications

Cholecystectomy is the most performed intra-abdominal surgical procedure in the US, with 1.2 million performed annually, and is predominantly performed laparoscopically. Although largely safe, laparoscopic cholecystectomy results in higher rates of abdominal symptoms consisting of abdominal pain and dyspepsia, which may persist or recur, collectively known as post-cholecystectomy syndrome. This article aims to (1) provide an overview of post-cholecystectomy syndrome with an emphasis on biliary complications and emergent imaging findings, (2) illustrate the spectrum of imaging findings of early and late post-cholecystectomy complications, (3) enumerate the role of various imaging modalities in evaluating post-cholecystectomy complications and address the role of selective trans-catheter coil embolization in managing bile leaks, and (4) discuss pearls and pitfalls in imaging following cholecystectomy. While common first-line imaging modalities for post-cholecystectomy complications include CT and sonography, ERCP and MRCP can delineate the biliary tree with greater detail. Scintigraphy has a higher sensitivity and specificity than CT or sonography for diagnosing bile leak and may preclude the need for ERCP. Post-operative complications include biliary duct injury or leak, biliary obstruction, remnant gallbladder/cystic duct stones and inflammation, biliary dyskinesia, papillary stenosis, and vascular injury. Subtle cases resulting in lethal outcomes, such as hemorrhage from the gallbladder bed without major vessel injury, have also been described. Cases presented will include biliary complications such as post-cholecystectomy stump cholecystitis, nonbiliary complications such as subcapsular hematoma, and normal post-surgical findings such as oxidized regenerated cellulose. Post-operative biliary complications can cause significant morbidity and mortality, and thus familiarity with the expected post-surgical appearance of the gallbladder fossa and biliary tract, as well as understanding the spectrum of complications and associated multimodality imaging findings, are essential for emergency radiologists and those practicing in the acute care setting to direct appropriate patient management. Furthermore, many of the postoperative complications can be managed by noninvasive percutaneous interventional procedures, from drain placement to cystic artery and cystic duct stump embolization.

Unnecessary endoscopic retrograde cholangiopancreatography associated with the spontaneous passage of common bile duct stones into the duodenum: a multicenter retrospective study

BACKGROUND

Unnecessary endoscopic retrograde cholangiopancreatography (ERCP) after spontaneous passage of common bile duct stones (CBDSs) should be avoided. This study aimed to examine the cumulative diagnosis rate and the predictive factors of spontaneous CBDS passage during the interval between the imaging diagnosis and ERCP.

METHODS

This multicenter retrospective study included 1260 consecutive patients with native papilla diagnosed with CBDSs using imaging modalities. Predictive factors and cumulative diagnosis rate of spontaneously passed CBDSs during the interval between imaging diagnosis and ERCP were analyzed.

RESULTS

The overall cumulative diagnosis rate of spontaneous CBDS passage was 6.2% (78/1260) during a mean interval of 5.0 days. In the multivariate analysis, CBDS sized < 6 mm on diagnostic imaging, solitary CBDS on diagnostic imaging, intervals between the imaging diagnosis and ERCP, and nondilated common bile duct (< 10 mm) were the significant factors associated with spontaneous CBDS passage. Specifically, the cumulative diagnosis rate of spontaneous passage was significantly higher in patients with solitary and CBDSs sized < 6 mm than in those with other CBDSs (14.4% [54/376] vs. 2.7% [24/884], P < 0.001). In both the asymptomatic and symptomatic groups, the cumulative diagnosis rate of the spontaneous passage of CBDSs was significantly higher in patients with solitary and CBDSs sized < 6 mm on diagnostic imaging than in those with multiple and/or CBDSs sized ≥ 6 mm on diagnostic imaging during a mean interval of 20.5 and 2.4 days, respectively (asymptomatic group: 22.4% [15/67] vs. 3.5% [4/113], P < 0.001, symptomatic group: 12.6% [39/309] vs. 2.6% [20/771], P < 0.001).

CONCLUSIONS

Solitary and CBDSs sized < 6 mm on diagnostic imaging can often lead unnecessary ERCP due to spontaneous passage. Preliminary endoscopic ultrasonography immediately before ERCP is recommended, especially in patients with solitary and small CBDSs on diagnostic imaging.

Endoscopic ultrasound versus magnetic resonance cholangiopancreatography for the diagnosis of computed tomography-negative common bile duct stone: Prospective randomized controlled trial

OBJECTIVES

For suspected common bile duct stone (CBDS) missed on computed tomography (CT), there is no clear evidence on whether endoscopic ultrasound (EUS) or magnetic resonance cholangiopancreatography (MRCP) is the better diagnostic tool. We aimed to compare the diagnostic accuracy of EUS and MRCP for cases of missed CBDS on CT.

METHODS

Patients suspected of having CBDS were enrolled and randomly allocated to the EUS or MRCP group. Upon the initial examination, those having CBDS or sludge formation underwent endoscopic retrograde cholangiopancreatography (ERCP), while those who were CBDS-negative underwent a second examination with either MRCP or EUS, which was distinct from the initial diagnostic procedure. The primary outcome was diagnostic accuracy, and the secondary outcomes were diagnostic ability, detection rate and characteristics of CBDS in the second examination, and the frequency of adverse events.

RESULTS

Between April 2019 and January 2021, 50 patients were enrolled in the study. The accuracy was 92.3% for EUS and 68.4% for MRCP (P = 0.055). EUS showed 100% sensitivity, 88.2% specificity, 81.8% positive predictive value, and 100% negative predictive value, and MRCP showed 33.3% sensitivity, 84.6% specificity, 50% positive predictive value, and 73.3% negative predictive value. The CBDS detection rate in the second examination was 0% for MRCP after a negative EUS and 35.7% for EUS after a negative MRCP (P = 0.041). No adverse events occurred in any of the patients.

CONCLUSIONS

Endoscopic ultrasound may be a superior diagnostic tool compared to MRCP for the detection of CBDS that are undetected on CT. (UMIN000036357).

Magnetic resonance imaging and other medical imaging techniques in the diagnosis of gallstones

Biliary diseases are one of the most common pathologies of the digestive system in the world. However, assessing the prevalence of biliary diseases is difficult, due to the asymptomatic course of the disease in some cases. Biliary diseases are a diagnostic problem, especially if a complicated course of the disease is suspected, and when the etiology cannot be established after laboratory examination and ultrasound imaging. Magnetic resonance imaging (MRI) is a highly specific non-invasive method for examining the gallbladder and imaging the bile ducts to identify gallstones, biliary strictures, tumors, and detect the level of obstruction. Magnetic resonance cholangiography/cholangiopancreatography (MRCP) is currently considered to be the most accurate non-invasive procedure for detecting bile duct stones, with high sensitivity, which allows to obtain a detailed image of the biliary tract. MRI is an established imaging technique for the biliary tract, has better contrast resolution, and is an excellent diagnostic tool. The choice of method to start the diagnosis with depends on many factors and requires careful interaction between the gastroenterologist and the radiologist to optimize the imaging technique.

Validity of MDCT cholangiography in differentiating benign and malignant biliary obstruction

Background

MDCT cholangiography can be utilized to identify variant biliary anatomy to guide preoperative planning of biliary surgery, and determine the cause and level of biliary obstruction. Early tumor detection and staging of biliary cancer are key factors for a possible cure by surgical resection. Between December 2019 and October 2020, 69 patients with clinically suspected biliary obstruction were enrolled in the study, subjected to clinical assessment (full history taking and clinical examination) and imaging assessment by MDCT cholangiography. Our findings were correlated to standard reference examinations including operative/ERCP/biopsy and histopathology findings.

Results

The most affected age was between 60 and 70 years old, and males were more affected. The commonest clinical presentation was yellowish discoloration of the skin and sclera followed by biliary colic. Right hypochondrial tenderness was the main clinical finding on clinical examination. Our patients were categorized according to the etiology of biliary obstruction into 7 groups: malignant stricture 52.2% (36 patients), calcular 24.6% (17 patients), iatrogenic 5.8% (4 patients), portahepatis lesions 5.8% (4 patients), benign stricture 4.3% (3 patients), inflammatory 4.3% (3 patients), and congenital 1.4% (1 patient). The malignant group shows dominant mass, moderate biliary obstruction, and arterial and venous enhancement. The overall sensitivity was 94% for malignancy.

Conclusion

MDCT cholangiography is non-invasive, fast, and highly sensitive and specific in the diagnosis of different causes and levels of biliary obstruction and is useful in the characterization of the lesion in cases of malignant obstruction and differentiating it from benign stricture. It can be used as an effective alternative to ERCP or PTC.

The Status and Development of Oral Choledochoscopy Diagnosis and Treatment of Biliary Tract Diseases

Choledochoscopy technology has realized the direct observation of bile duct lesions, and can be loaded with a variety of special accessories to perform the corresponding diagnosis and treatment operations, and has become an important means for the diagnosis of unexplained bile duct stricture and treatment of refractory bile duct stones. With the further enhancement of the imaging quality and operability, the clinical application of choledochoscopy has gradually expanded to the precise positioning of cholangiocarcinoma before surgical resection, the drainage of the gallbladder through the nipple, the removal of the displaced bile duct stent and other fields. This paper briefly reviewed the historical evolution of choledochoscopy and reviewed the latest clinical advances of oral choledochoscopy in the diagnosis and treatment of biliary tract diseases.

Management of cholelithiasis with choledocholithiasis: Endoscopic and surgical approaches

Gallstone disease and complications from gallstones are a common clinical problem. The clinical presentation ranges between being asymptomatic and recurrent attacks of biliary pain requiring elective or emergency treatment. Bile duct stones are a frequent condition associated with cholelithiasis. Amidst the total cholecystectomies performed every year for cholelithiasis, the presence of bile duct stones is 5%-15%; another small percentage of these will develop common bile duct stones after intervention. To avoid serious complications that can occur in choledocholithiasis, these stones should be removed. Unfortunately, there is no consensus on the ideal management strategy to perform such. For a long time, a direct open surgical approach to the bile duct was the only unique approach. With the advent of advanced endoscopic, radiologic, and minimally invasive surgical techniques, however, therapeutic choices have increased in number, and the management of this pathological situation has become multidisciplinary. To date, there is agreement on preoperative management and the need to treat cholelithiasis with choledocholithiasis, but a debate still exists on how to cure the two diseases at the same time. In the era of laparoscopy and mini-invasiveness, we can say that therapeutic approaches can be performed in two sessions or in one session. Comparison of these two approaches showed equivalent success rates, postoperative morbidity, stone clearance, mortality, conversion to other procedures, total surgery time, and failure rate, but the one-session treatment is characterized by a shorter hospital stay, and more cost benefits. The aim of this review article is to provide the reader with a general summary of gallbladder stone disease in association with the presence of common bile duct stones by discussing their epidemiology, clinical and diagnostic aspects, and possible treatments and their advantages and limitations.

Remaining issues of recommended management in current guidelines for asymptomatic common bile duct stones

Current guidelines for treating asymptomatic common bile duct stones (CBDS) recommend stone removal, with endoscopic retrograde cholangiopancreatography (ERCP) being the first treatment choice. When deciding on ERCP treatment for asymptomatic CBDS, the risk of ERCP-related complications and outcome of natural history of asymptomatic CBDS should be compared. The incidence rate of ERCP-related complications, particularly of post-ERCP pancreatitis for asymptomatic CBDS, was reportedly higher than that of symptomatic CBDS, increasing the risk of ERCP-related complications for asymptomatic CBDS compared with that previously reported for biliopancreatic diseases. Although studies have reported short- to middle-term outcomes of natural history of asymptomatic CBDS, its long-term natural history is not well known. Till date, there are no prospective studies that determined whether ERCP has a better outcome than no treatment in patients with asymptomatic CBDS or not. No randomized controlled trial has evaluated the risk of early and late ERCP-related complications vs the risk of biliary complications in the wait-and-see approach, suggesting that a change is needed in our perspective on endoscopic treatment for asymptomatic CBDS. Further studies examining long-term complication risks of ERCP and wait-and-see groups for asymptomatic CBDS are warranted to discuss whether routine endoscopic treatment for asymptomatic CBDS is justified or not.

Dual-layer spectral detector computed tomography versus magnetic resonance cholangiopancreatography for biliary stones

OBJECTIVE

Dual-layer spectral detector computed tomography (DLCT) can detect noncalcified biliary stones. The diagnostic ability of DLCT for detecting biliary stones may be comparable to that of magnetic resonance cholangiopancreatography (MRCP). This study seeks to compare the diagnostic ability for biliary stones between these two imaging modalities.

METHODS

This retrospective study included 102 cases with a diagnosis of biliary stones including gallstones (n = 66) and common bile duct (CBD) stones (n = 25) or spontaneously passing CBD stones (n = 11). The reference standard used was operative findings, endoscopic retrograde cholangiopancreatography or follow-up over 6 months. In DLCT, 120-kVp images, 40-keV virtual monoenergetic images and material decomposition images were created. We compared the diagnostic ability of DLCT and MRCP for biliary stones using the McNemar's test.

RESULTS

The sensitivity and specificity of DLCT versus MRCP for biliary stones were 91.2% versus 95.6% and 90.9% versus 90.9%. Thus, the sensitivity and specificity were not significantly different (P = 0.25 and P = 1.0). Although in small stones (<9 mm) the sensitivity of calcified stones was not different between DLCT and MRCP (100% versus 92.5%), the sensitivity of noncalcified stones in DLCT was lower than that in MRCP (38.5% versus 100%).

CONCLUSION

The diagnostic ability of biliary stones in DLCT appears comparable to that of MRCP in overall cases. However, detecting noncalcified stones less than 9 mm in size is limited in DLCT.

Combination of serum gamma-glutamyltransferase and alkaline phosphatase in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis

BACKGROUND

Gamma-glutamyltransferase (GGT) is one of the most important laboratory tests for the evaluation of liver damage. Through a long-term clinical observation of patients with secondary asymptomatic choledocholithiasis, we found that most patients had abnormal GGT serum levels.

AIM

To investigate the combination of serum GGT and alkaline phosphatase (ALP) in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis.

METHODS

In this retrospective cohort study, the clinical data of 829 patients with cholecystolithiasis admitted to the Third Affiliated Hospital of Zunyi Medical College from August 2014 to August 2017 were collected. Among these patients, 151 patients had secondary asymptomatic choledocholithiasis and served as the observation group, and the remaining 678 cholecystolithiasis patients served as the control group. Serum liver function indexes were detected in both groups, and the receiver operating characteristic (commonly known as ROC) curves were constructed for markers showing statistical significances. The cutoff value, sensitivity, and specificity of each marker were calculated according to the ROC curves.

RESULTS

The overall incidence of asymptomatic choledocholithiasis secondary to cholecystolithiasis was 18.2%. The results of liver function indexes including serum aspartate aminotransferase, alanine aminotransferase, direct bilirubin and total bilirubin levels showed no significant differences between the two groups (P > 0.05). However, the serum GGT and ALP levels were significantly higher in the observation group than in the control group (P < 0.05). The ROC curve analysis showed that the area under the curve was 0.881 (95%CI: 0.830-0.932), 0.647 (95%CI: 0.583-0.711) and 0.923 (95%CI: 0.892-0.953) for GGT, ALP, and GGT + ALP, respectively. The corresponding cut-off values of GGT and ALP were 95.5 U/L and 151.5 U/L, sensitivity were 90.8% and 65.1%, and specificity were 83.6% and 59.8%, respectively. The sensitivity and specificity of GGT + ALP were 93.5% and 85.1%, respectively.

CONCLUSION

An abnormally elevated serum GGT level has an important value in the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis. The combination of serum GGT and ALP has better diagnostic performance. As a convenient, rapid and inexpensive test, it should be applied in secondary asymptomatic choledocholithiasis routine screening.

Updated guideline on the management of common bile duct stones (CBDS)

Common bile duct stones (CBDS) are estimated to be present in 10-20% of individuals with symptomatic gallstones. They can result in a number of health problems, including pain, jaundice, infection and acute pancreatitis. A variety of imaging modalities can be employed to identify the condition, while management of confirmed cases of CBDS may involve endoscopic retrograde cholangiopancreatography, surgery and radiological methods of stone extraction. Clinicians are therefore confronted with a number of potentially valid options to diagnose and treat individuals with suspected CBDS. The British Society of Gastroenterology first published a guideline on the management of CBDS in 2008. Since then a number of developments in management have occurred along with further systematic reviews of the available evidence. The following recommendations reflect these changes and provide updated guidance to healthcare professionals who are involved in the care of adult patients with suspected or proven CBDS. It is not a protocol and the recommendations contained within should not replace individual clinical judgement.

Comparison of Virtual Unenhanced Images Derived From Dual-Energy CT With True Unenhanced Images in Evaluation of Gallstone Disease

OBJECTIVE

The aim of this study was to compare gallstones on virtual unenhanced images and true unenhanced images acquired with dual-energy CT (DECT).

MATERIALS AND METHODS

We enrolled 112 patients with right upper quadrant pain and clinically suspected acute cholecystitis or gallstone who underwent DECT--including unenhanced, arterial, and portal phases. Eighty-three gallstones with composition proven by semiquantitative Fourier transform infrared spectroscopy from 45 patients who had undergone cholecystectomy (40 cholesterol gallstones from 21 patients, 43 calcium gallstones from 24 patients) were included. CT images were retrospectively evaluated for stone size, contrast-to-noise ratio (CNR) of gallstone to bile, and visibility and density of gallstones for each image set. The visibility of each type of stone was compared with a paired t test.

RESULTS

Both cholesterol and calcium stones measured smaller on virtual unenhanced images than on true unenhanced images, yielding a lower sensitivity of virtual unenhanced images for detecting small gallstones. Mean CNR of cholesterol stones was 2.45 ± 1.32 versus 1.67 ± 1.55 (p < 0.032) and that of calcium stones was 10.59 ± 7.15 and 14.11 ± 9.81 (p < 0.001) for virtual unenhanced and true unenhanced images, respectively. For calcium stones, two readers found 43 of 43 (100%) on true unenhanced images; one reader found 41 of 43 (95%) and the other, 37 of 43 (86%) on virtual unenhanced images. For cholesterol stones, one reader found 20 of 40 (50%) and the other 19 of 40 (47%) on true unenhanced images versus 34 of 40 (85%) and 30 of 40 (75%), respectively, on virtual unenhanced images. The visibility of cholesterol stones was higher on virtual unenhanced images, but that of calcium stones was lower.

CONCLUSION

Virtual unenhanced images at DECT allow better visualization of cholesterol gallstones, but true unenhanced images allow better visualization of calcium and small gallstones.

Endoscopic management of radio-opaque bile duct stones

BACKGROUND

Majority of the bile duct stones (BDS) are radiolucent (RL) and are amenable to conventional endoscopic extraction techniques. There is no publication that specifically discusses the optimal management of radio-opaque (RO) BDS and makes a distinction from the strategy followed for RL BDS.

METHODS

Data of patients with BDS managed endoscopically from January 2009 till June 2015 were retrospectively reviewed. Diagnosis of RO stone was established during initial fluoroscopy, just prior to obtaining a cholangiogram. Endoscopic retrograde cholangiopancreatography (ERCP) was done using therapeutic duodenoscope. Stone extraction was attempted initially using conventional techniques. Balloon sphincteroplasty or mechanical lithotripsy (ML) or both were done if conventional techniques failed. Cholangioscopy-guided intracorporeal holmium laser lithotripsy (LL) was done when all the above techniques failed.

RESULTS

Fifteen patients were found to have RO stones in the bile duct during the study period. ERCP was successful in all patients. Discrepancy of the stone size in relation to the lower CBD diameter was seen in eight patients (53.34 %). Stone extraction with conventional techniques was successful in 2/15 patients (13 %). Successful controlled radial expansion (CRE) balloon sphincteroplasty/ML was possible in 5/15 patients (33 %). Cholangioscopy guided LL was done in eight patients (53.34 %) with successful pulverization of RO BDS (100 %).

CONCLUSIONS

RO bile duct stones provide unique challenges for endoscopic management with success of conventional techniques in only about half of them (46 %). RO stones detected on fluoroscopy are extremely hard and difficult to crush with lithotripsy basket probably due to high calcium content. Cholangioscopy guided LL provides an excellent alternative management strategy.

Diagnosis and management of choledocholithiasis in the golden age of imaging, endoscopy and laparoscopy

Biliary lithiasis is an endemic condition in both Western and Eastern countries, in some studies affecting 20% of the general population. In up to 20% of cases, gallbladder stones are associated with common bile duct stones (CBDS), which are asymptomatic in up to one half of cases. Despite the wide variety of examinations and techniques available nowadays, two main open issues remain without a clear answer: how to cost-effectively diagnose CBDS and, when they are finally found, how to deal with them. CBDS diagnosis and management has radically changed over the last 30 years, following the dramatic diffusion of imaging, including endoscopic ultrasound (EUS) and magnetic resonance cholangiography (MRC), endoscopy and laparoscopy. Since accuracy, invasiveness, potential therapeutic use and cost-effectiveness of imaging techniques used to identify CBDS increase together in a parallel way, the concept of "risk of carrying CBDS" has become pivotal to identifying the most appropriate management of a specific patient in order to avoid the risk of "under-studying" by poor diagnostic work up or "over-studying" by excessively invasive examinations. The risk of carrying CBDS is deduced by symptoms, liver/pancreas serology and ultrasound. "Low risk" patients do not require further examination before laparoscopic cholecystectomy. Two main "philosophical approaches" face each other for patients with an "intermediate to high risk" of carrying CBDS: on one hand, the "laparoscopy-first" approach, which mainly relies on intraoperative cholangiography for diagnosis and laparoscopic common bile duct exploration for treatment, and, on the other hand, the "endoscopy-first" attitude, variously referring to MRC, EUS and/or endoscopic retrograde cholangiography for diagnosis and endoscopic sphincterotomy for management. Concerning CBDS diagnosis, intraoperative cholangiography, EUS and MRC are reported to have similar results. Regarding management, the recent literature seems to show better short and long term outcome of surgery in terms of retained stones and need for further procedures. Nevertheless, open surgery is invasive, whereas the laparoscopic common bile duct clearance is time consuming, technically demanding and involves dedicated instruments. Thus, although no consensus has been achieved and CBDS management seems more conditioned by the availability of instrumentation, personnel and skills than cost-effectiveness, endoscopic treatment is largely preferred worldwide.

Modern approach to cholecysto-choledocholithiasis

Gallstones and common bile duct calculi are found to be associated in 8%-20% of patients, leading to possible life-threatening complications, such as acute biliary pancreatitis, jaundice and cholangitis. The gold standard of care for gallbladder calculi and isolated common bile duct stones is represented by laparoscopic cholecystectomy and endoscopic retrograde cholangiopancreatography, respectively, while a debate still exists regarding how to treat the two diseases at the same time. Many therapeutic options are also available when the two conditions are associated, including many different types of treatment, which local professionals often administer. The need to limit maximum discomfort and risks for the patients, combined with the economic pressure of reducing costs and utilizing resources, favors single-step procedures. However, a multitude of data fail to strongly demonstrate the superiority of any technique (including a two or multi-step approach), while rigorous clinical trials that include so many different types of treatment are still lacking, and it is most likely unrealistic to conduct them in the future. Therefore, the choice of the best management is often led by the local presence of professional expertise and resources, rather than by a real superiority of one strategy over another.