Magnetic Resonance Cholangiopancreatography Findings Research Articles

EGS P12 To Perform Magnetic Resonance Cholangiopancreatography or Not in Gallstone Pancreatitis? – A Single Centre Retrospective Cohort Study

Abstract Background The management of gallstone pancreatitis (GSP) is well-described in guidelines from the Association of Upper Gastrointestinal Surgeons (AUGIS) and British Society of Gastroenterologists (BSG). Guidelines recommend laparoscopic cholecystectomy (LC) for mild GSP within 2 weeks of the admission, with endoscopic retrograde cholangiopancreatography (ERCP) as second-line for unfit patients. Magnetic resonance cholangiopancreatography (MRCP) plays a pivotal role in excluding choledocholithiasis. Our aim was to determine if MRCP is required to rule out choledocholithiasis in patients with GSP. Methods A retrospective cohort study of all consecutive adult patients who had MRCP for GSP in a single centre from September 2020 to September 2022 was conducted. Patient demographics, pre-MRCP peak liver function test (LFT) values and MRCP findings were analysed. Patients were risk-stratified based on modified AUGIS guidelines using the presence of hyperbilirubinaemia and the presence of biliary duct dilation on other imaging modalities. Patients with MRCP-proven choledocholithiasis were compared to those without. P-values were calculated using Fisher’s exact test. This study was registered with Clinical Quality Project (LanQIP 14738). Results 138 patients were identified; median age was 61 years (IQR 45-73) and 95 (68.8%) were female. 20 (14.5%) patients were post-cholecystectomy. 115 (83.3%) had inpatient scans and 66 (47.8%) were urgent. Median waiting time for inpatient MRCPs was 1.1 days (IQR 0.8-1.9) and 22.9 days (IQR 13.4-28.0) for outpatient scans. 25 (78.1%) patients had raised alkaline phosphatase levels and 23 (71.9%) had hyperbilirubinaenia. 61.1% of abdominal ultrasounds and 38.5% of CT scans reported dilated bile ducts. MRCP yielded 32 patients (23.2%) with choledocholithiasis, 3 of whom were post-cholecystectomy. Choledocholithiasis on MRCP was strongly correlated to higher risk stratification. Conclusions MRCP is useful imaging modality determining the presence of choledocholithiasis in high and moderate risk patients with GSP. We recommend that intraoperative cholangiography should still be performed during laparoscopic cholecystectomy where expertise is available.

The role of magnetic resonance cholangiopancreatography in evaluation of etiological spectrum of obstructive jaundice

Jaundice is a commonly encountered problem in society. Discrimination between obstructive and non-obstructive causes is important to imply surgical intervention in cases of obstructive jaundice whereas medical management in non-obstructive jaundice. Nowadays diagnostic endoscopic retrograde cholangiopancreatography (ERCP) may be replaced by Magnetic resonance cholangiopancreatography (MRCP) as it has high level of resolution and reliability. We studied the role of MRCP in obstructive jaundice to evaluate its etiological spectrums and radiological findings. To evaluate the role of MRCP in the determination of aetiologies in obstructive jaundice, to assess degree and level of biliary obstruction and to correlate MRCP findings with post surgical follow-ups / ERCP/ histopathology. Total sixty-eight patients with a clinical diagnosis of obstructive jaundice referred for MRCP were included in our study. We correlated MRCP findings with the final diagnosis made by post-surgical follow-up / ERCP/ histopathology as a gold standard. For benign lesions, overall sensitivity of MRCP was 97.73%, specificity was 95.83% with an accuracy of 97.06%. MRCP had 94.74% sensitivity, 93.88% specificity, 94.12% accuracy in the diagnosis of choledocholithiasis, and 66.67% sensitivity, 98.39% specificity, and 95.59% accuracy in the diagnosis of benign strictures. For malignant lesions, accuracy, sensitivity, and specificity of MRCP were 97.06%, 95.83%, and 97.73%. MRCP is a highly reliable, accurate, non-invasive imaging technique and has a high sensitivity for the evaluation of aetiologies of obstructive jaundice.

The role of serology, liver function tests and imaging in screening of primary sclerosing cholangitis: the HelPSCreen score

Objecives At present, no sensitive or specific screening test exists for primary sclerosing cholangitis (PSC). PSC screening is mainly based on elevated alkaline phosphatase (ALP) in patients with inflammatory bowel disease (IBD). We aimed to produce a screening score based on laboratory tests to predict the likelihood of PSC. Moreover, we evaluated the additional roles of liver histology and magnetic resonance cholangiopancreatography (MRCP) in the diagnosis of PSC. Materials and methods The data of 385 patients who came for their first endoscopic retrograde cholangiography (ERC) to confirm PSC diagnosis were retrieved from the PSC registry of the Helsinki University Hospital. Overall, 69 patients referred for ERC with suspected PSC, in whom PSC was excluded by ERC or liver biopsy and MRCP, served as controls. We included patients’ demographics and 13 laboratory test results in the analysis. Variables with significant odds ratios were selected for multivariate logistic regression, which was used to create a novel scoring system for PSC. The presence of IBD, serum perinuclear anti-neutrophil cytoplasmic antibodies, and ALP levels demonstrated the highest predictive value for PSC. A score was assigned for each statistically significant predictor. Results The optimal cut-off point for the score was ≥3, with an AUC of 0.83 (95%CI: 0.78–0.88). The addition of liver histology or MRCP findings to the score did not add a predictive value. Concusions In conclusion, we created a novel, simple scoring system to screen the probability of PSC. The HelPSCreen-score may help to assess the disease prevalence and to target further investigations in patients suspected of PSC.

Comparison of MRCP and ERCP in the evaluation of common bile duct and pancreatic duct pathologies.

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging modality that has high diagnostic accuracy for a wide range of bile duct and pancreatic duct pathologies. Endoscopic retrograde cholangiopancreatography (ERCP) is still the gold standard for the exploration of the biliopancreatic region. The aim of the study was to compare the diagnostic accuracy of MRCP with that of ERCP in the diagnosis of bile duct and pancreatic duct pathologies. A total of 60 patients with common bile duct (CBD) and pancreatic duct pathologies detected on MRCP were subsequently evaluated by ERCP in this observational study. A comparison of MRCP findings with ERCP was made. MRCP had a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 88.1%, 94.4%, 97.3%, 72.7%, and 90%, respectively, in diagnosing choledocholithiasis in comparison to ERCP. For CBD dilation, the sensitivity was 90.91%, specificity was 93.75% and the PPV, NPV, and accuracy were 97.56%, 78.95%, and 91.67%, respectively, for MRCP. In CBD stricture, MRCP showed a sensitivity, specificity, PPV, NPV, and accuracy of 83.33%, 97.92%, 90.91%, 95.92%, and 95%, respectively. In pancreatic duct dilatation, the sensitivity, specificity, PPV, NPV, and accuracy were all 100%. Pancreatic duct stricture showed a sensitivity, specificity, PPV, NPV, and accuracy of 80%, 98%, 88.89%, 96.08%, and 95%, respectively. For the diagnosis of periampullary carcinoma, the sensitivity, specificity, PPV, NPV, and accuracy rate of MRCP were 80%, 98%, 88.89%, 96.08%, and 95%, respectively. No significant difference was found between MRCP and ERCP in diagnosing those six pathologies.

How do magnetic resonance cholangiopancreatography findings predict conversion from laparoscopic cholecystectomy for acute cholecystitis to bailout procedures?

BackgroundAcute cholecystitis is one of the most prevalent surgical abdominal conditions. The Tokyo Guidelines describe the management of acute cholecystitis and recommend bailout procedures for “difficult” cholecystitis cases. This study aimed to identify risk factors for conversion from laparoscopic cholecystectomy to bailout procedures in patients with acute cholecystitis. MethodsThis retrospective cohort study was conducted at a single center between January 2017 and December 2021. Patients who underwent laparoscopic cholecystectomy for acute cholecystitis were enrolled and classified into bailout and non-bailout groups. The patients’ characteristics and perioperative data were compared between the 2 groups. ResultsIn total, 161 patients who underwent laparoscopic cholecystectomy for acute cholecystitis were reviewed. Fourteen were excluded because of a lack of preoperative magnetic resonance cholangiopancreatography; thus, 147 patients were enrolled (bailout group, 21; non-bailout group, 126). Age (74 vs 67 years old; P = .048), days from onset to surgery (3 vs 2 days; P = .02), or defect of cystic duct in magnetic resonance cholangiopancreatography (57% vs 29%; P = .02) were significantly associated with conversion to bailout procedures. In the logistic regression analysis, a defect of the cystic duct in magnetic resonance cholangiopancreatography was an independent predictor for bailout procedures (odds ratio, 2.793; P = .04). ConclusionIn this study, defect of the cystic duct in the magnetic resonance cholangiopancreatography can predict conversion to bailout procedures. To the best of our knowledge, this is the first report to describe magnetic resonance cholangiopancreatography finding of the cystic duct as a predictor of surgical difficulty in patients with acute cholecystitis.

The accuracy of magnetic resonance cholangiopancreatography in the diagnosis of biliary atresia in preterm infants with cholestasis.

Magnetic resonance cholangiopancreatography (MRCP) is a useful and non-invasive method to diagnose biliary atresia (BA) in term infants, however few studies have investigated its use in preterm infants. This study aimed to evaluate the accuracy of MRCP in the diagnosis of BA in preterm infants with cholestasis. Infants aged less than 6 months who received MRCP for cholestasis at a tertiary medical center were enrolled from 2011 to 2020. Demographic and laboratory data were retrospectively obtained. One pediatric radiologist reviewed the MRCP images. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRCP to diagnose BA based on surgical proof or at least 6 months of follow-up were assessed. A total of 80 infants (36 preterm and 44 term) were analyzed. The mean post-chronological age was 1.8 months, and the female-to-male ratio was 0.78. Six (16.7%) preterm and 16 (36.4%) term infants were confirmed to have BA. BA was obscured by a choledochal cyst preoperatively in two term infants. In the preterm infants, the sensitivity, specificity, PPV, NPV, and accuracy of MRCP to diagnose BA were 100%, 77%, 46%, 100%, and 81%, respectively, compared to 81%, 86%, 76%, 89%, and 84% in the term infants. Using MRCP to differentiate BA from other cholestasis in the preterm infants had superior sensitivity (100% vs. 81%) and NPV (100% vs. 89%), and lower specificity (77% vs. 86%) and PPV (46% vs. 76%) than in the term infants. Negative MRCP findings can be used to exclude BA in preterm infants with cholestasis based on a favorable NPV.

HPB P57 Acalculous Cholecystitis – Does it need a redefinition?

Abstract Background Acalculous cholecystitis (AC) is a necroinflammatory disorder of the gallbladder in the absence of gallstones. AC is a diagnostic challenge due to absence of clear published diagnostic criteria. Though diagnosis is dependent upon radiological findings in combination with clinical findings and blood results, it can only be confirmed after analysis of operative findings and post-operative histology. This study aims to assess the correlation between pre-operative imaging and post-operative histology. Methods Data was retrospectively collected for all patients with a diagnosis of cholecystitis (March 2018 - March 2020) by reviewing ultrasound, computerised tomography and magnetic resonance cholangiopancreatography findings. Patients without any clinical/radiological signs of cholecystitis and with confirmed gallstones on imaging were excluded. A total of 61 patients were identified with AC. Results Twenty-one patients underwent cholecystectomy at time of data collection. Eleven patients had histological evidence of AC; histology results only showed acute/chronic cholecystitis. Out of these 11 patients, pre-operative imaging from at least one imaging modality showed biliary sludge/microlithiasis in 9 patients. Overall, 13 patients did not have biliary sludge/microlithiasis on pre-operative imaging. Correlating histology results showed 2 patients with gallstones, 1 patient with cholesterolosis, 9 patients with acute/chronic cholecystitis alone and 1 normal gallbladder. Among the 8 patients with biliary sludge/microlithiasis on imaging, histology results identified 1 patient with gallstones, 5 patients with cholesterolosis and 2 patients with acute/chronic cholecystitis alone. Conclusions Given improvement in diagnostics in detecting biliary sludge, the classical definition of AC may no longer be valid. This study suggests that a new classification may be necessary.

Development of a prognostic MRCP-score (DiStrict) for individuals with large-duct primary sclerosing cholangitis

Magnetic resonance cholangiopancreatography (MRCP) is used for the diagnosis and follow-up of individuals with primary sclerosing cholangitis (PSC). The aim of our study is to develop an MRCP-score based on cholangiographic findings previously associated with outcomes and assess its reproducibility and prognostic value in PSC. The score (DiStrict score) was developed based on the extent and severity of cholangiographic changes of intrahepatic and extrahepatic bile ducts (range 0-8) on 3D-MRCP. In this retrospective, multicentre study, three pairs of radiologists with different levels of expertise from three tertiary centres applied the score independently. MRCP examinations of 220 consecutive individuals with PSC from a prospectively collected PSC-cohort, with median follow-up of 7.4 years, were reviewed. Inter-reader and intrareader agreements were assessed via intraclass correlation coefficient (ICC). After consensus, the prognostic value of the score was assessed using Cox-regression and outcome-free survival rates were assessed via Kaplan-Meier estimates. Harrell's C-statistic was calculated. Forty patients developed outcomes (liver transplantation or liver-related death). Inter-reader agreement between experienced radiologists was good (ICC 0.82; 95% CI 0.74-0.87, and ICC 0.81; 95% CI 0.70-0.87, respectively) and better than the agreement for the pair of experienced/less-experienced radiologists (ICC 0.48; 95% CI 0.05-0.72). Agreement between radiologists from the three centres was good (ICC 0.76; 95% CI 0.57-0.89). Intrareader agreement was good to excellent (ICC 0.85-0.93). Harrell's C was 0.78. Patients with a DiStrict score of 5-8 had 8.2-fold higher risk (hazard ratio 8.2; 95% CI 2.97-22.65) of developing outcomes, and significantly worse survival (p <0.001), compared to those with a DiStrict score of 1-4. The novel DiStrict score is reproducible and strongly associated with outcomes, indicating its prognostic value for individuals with PSC in clinical practice. The diagnosis of primary sclerosing cholangitis (PSC)is based on magnetic resonance cholangiopancreatography (MRCP). However, the role of MRCP in the prognostication of PSC is still unclear. We developed a novel, simple, and reproducible risk-score, based on MRCP findings, that showed a strong association with prognosis in individuals with PSC (DiStrict score). This score can be easily used in clinical practice and thus has the potential to be useful inclinical trials and in patient counselling and management.

Ectopic opening of common bile duct into the duodenal bulb: magnetic resonance cholangiopancreatography findings.

PURPOSE We aimed to evaluate the spectrum of magnetic resonance cholangiopancreatography (MRCP) findings in patients with ectopic opening of the common bile duct (CBD) into the duodenal bulb and to determine the effectiveness of the MRCP technique in diagnosis. METHODS Morphologic and morphometric MRCP/MRI features in 16 patients and 36 controls were retrospectively analyzed by 2 radiologists. The frequency of MRCP findings was determined. The significance of the difference between the MRCP observations in patients and controls was evaluated statistically and the diagnostic effectiveness of MRCP was investigated. RESULTS Hook-shaped ending of CBD and bulbar deformity were the most frequent morphologic findings seen on MRCP in the ectopic bulbar opening. Mean pylorus-papilla distance and mean CBD length were significantly shorter and the median diameter of CBD was significantly larger than the control group (patients: 28.6 ± 15.3 mm, 33.7 ± 12.8 mm, 8.6 (2-16) mm; controls: 66.7 ± 11.7 mm, 50.3 ± 14.4 mm, 3.2 (1.5-10) mm, P < .001, respectively). Receiver operating curve analysis showed sensitivity and specificity of MRCP in the diagnosis to be 87.5% and 100%, respectively, if any 3 of the 4 signs (hook-shaped ending of CBD, bulbar deformity, large, and short CBD) were present in a patient whose pylorus-papilla distance was <50 mm. CONCLUSION At MRCP, the presence of short and large CBD with a hook-shaped ending in the deformed duodenal bulb may support the diagnosis of ectopic biliary drainage.

Role of Magnetic Resonance Cholangiopancreatography (MRCP) in Evaluation of Pancreaticobiliary Pathologies and Correlation with Ultrasound Findings

Background- In this prospective study, we evaluated the role of magnetic resonance cholangiopancreatography (MRCP) as an imaging modality for identification and characterization of various pancreaticobiliary pathologies and to correlate MRCP findings with ultrasound (USG) findings. Methodology–This study was carried out as an observational study in Department of Radiodiagnosis, GMC Bhopal, for a study period of 20 months on patients suspected with pancreaticobiliary pathologies reporting for ultrasound examination. MRCP was performed following Ultrasound imaging (USG) with subsequent comparison of findings. Results- The sensitivity, specificity and diagnostic accuracy of ultrasound in detection of CBD dilatation were 86.21%. 100% and 92% respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of ultrasound in detection of intrahepatic biliary radicle (IHBR) dilatation was 81.97%. 97.44%. 98.04%. 77.55% and 88% respectively. The sensitivity of USG for identification of benign lesions was 93.55% whereas that for malignant lesions was 96.15%. Overall, diagnostic accuracy of USG for identification of benign and malignant lesions was 84% and 87% respectively. Conclusion– Although abdominal ultrasound continues to serve as a screening tool for detection of pancreaticobiliary pathologies and allows for differentiation between surgical and non-surgical causes of obstructive jaundice, the in-depth characterization of lesions as provided by magnetic resonance imaging (MRI) with MRCP suggests that it serves as an indispensable adjunct to endoscopic retrograde cholangiopancreatography (ERCP). MRCP with MRI serves as an accurate and non-invasive, non-ionizing imaging method for evaluation of biliary anatomy and pathology especially in cases of obese patients where ultrasound results are compromised.

Comparison of Ultrasound and MRI Findings in the Evaluation of Pelvic masses/lesions with Histopathological Correlation in Female Patients

Background- In this prospective study, we evaluated the role of magnetic resonance cholangiopancreatography (MRCP) as an imaging modality for identification and characterization of various pancreaticobiliary pathologies and to correlate MRCP findings with ultrasound (USG) findings. Methodology–This study was carried out as an observational study in Department of Radiodiagnosis, GMC Bhopal, for a study period of 20 months on patients suspected with pancreaticobiliary pathologies reporting for ultrasound examination. MRCP was performed following Ultrasound imaging (USG) with subsequent comparison of findings. Results- The sensitivity, specificity and diagnostic accuracy of ultrasound in detection of CBD dilatation were 86.21%. 100% and 92% respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of ultrasound in detection of intrahepatic biliary radicle (IHBR) dilatation was 81.97%. 97.44%. 98.04%. 77.55% and 88% respectively. The sensitivity of USG for identification of benign lesions was 93.55% whereas that for malignant lesions was 96.15%. Overall, diagnostic accuracy of USG for identification of benign and malignant lesions was 84% and 87% respectively. Conclusion– Although abdominal ultrasound continues to serve as a screening tool for detection of pancreaticobiliary pathologies and allows for differentiation between surgical and non-surgical causes of obstructive jaundice, the in-depth characterization of lesions as provided by magnetic resonance imaging (MRI) with MRCP suggests that it serves as an indispensable adjunct to endoscopic retrograde cholangiopancreatography (ERCP). MRCP with MRI serves as an accurate and non-invasive, non-ionizing imaging method for evaluation of biliary anatomy and pathology especially in cases of obese patients where ultrasound results are compromised.

Diagnostic accuracy of magnetic resonance cholangiopancreatography in patients with extrahepatic cholestasis: a retrospective cohort study

Background/Aims: Differential diagnosis of extrahepatic cholestasis can be challenging due to variable sensitivity and specificity rates of imaging techniques. Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive method used for evaluation of biliary tree. We aimed to investigate diagnostic accuracy of MRCP in biliary obstruction. &#x0D; Materials and Methods: Medical records of patients admitted with extrahepatic cholestasis between January 2012 and December 2016 were retrospectively reviewed. Patients who had endoscopic retrograde cholangiopancreatography (ERCP) following MRCP were included. Demographic and clinical characteristics of patients were noted. Final diagnosis of ERCP was accepted as gold standard. Diagnostic efficiency of MRCP was evaluated by calculating sensitivity, specificity, accuracy, negative and positive predictive values as compared with ERCP.&#x0D; Results: There were 615 patients with a mean age of 60.1±17.5 years. Using MRCP, choledocholithiasis, malignant and benign strictures were diagnosed in 337 (54.8%), 101 (16.4%), and 39 patients (6.3%), respectively. Normal MRCP findings were present in 65 patients (10.6%). Final diagnoses via ERCP were as follows: choledocholithiasis (n=390, 63.4%), malignant stricture (n=152, 24.7%), benign stricture (n=62, 10.1%), and normal findings (n=11, 1.8%). Sensitivity and specificity of MRCP were 70.8% and 72.9% for choledocholithiasis, 55.9% and 96.5% for malign stricture, and 16.1% and 94.8% for benign stricture, respectively. Overall accuracy rates were 71.5%, 86.5%, and 86.8% for choledocholithiasis, malign and benign strictures, respectively.&#x0D; Conclusion: Diagnostic accuracy of MRCP is variable for different biliary/cholestatic etiologies. Due to a lower sensitivity for choledocholithiasis, normal MRCP findings should be handled with caution, especially when there is a clinical suspicion for biliary obstruction. &#x0D; Keywords: extrahepatic cholestasis, magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiopancreatography, sensitivity, specificity.

Magnetic Resonance Cholangiopancreatography vs Endoscopy Retrograde Cholangiopancreatography for Detection of Anatomic Variants of the Pancreatic Duct in Children

To compare the efficacy of magnetic resonance cholangiopancreatography (MRCP) with endoscopy retrograde cholangiopancreatography (ERCP) in children for the identification of pancreatic duct variants. We identified children with a pancreatic duct variant by ERCP and separately queried our MRCP database for similar variants. Patients with a paired ERCP-MRCP were reviewed. Three radiologists blinded to the ERCP and MRCP findings were asked to independently review the MRCP studies and define the pancreatic duct anatomy. These blinded reviewers also graded the magnetic resonance imaging examination quality. Seventy-four pairs of ERCP-MRCP examinations were identified. Pancreas divisum was the most frequent ductal variant encountered (73%). There was fair agreement between the radiology reviewers as to the quality of the magnetic resonance imaging studies (Fleiss Kappa agreement). Concordance of the reviewers with that of the ERCP was moderate for the exact diagnosis, moderate for the presence of pancreas divisum, and fair for agreement on the presence of any duct variant. Concordance among reviewers was moderate for the exact diagnosis, moderate for normal vs abnormal, and substantial for the presence of pancreas divisum. Diagnostic limitations exist when comparing MRCP with the gold reference standard of ERCP, specifically when assessing for pancreatic duct variants in children.

Accuracy of Ultrasound and Magnetic Resonance Cholangiopancreatography Findings in the Diagnosis of Biliary System Stones

This study aimed to evaluate the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) and Ultrasound (US) images for the diagnosis of biliary system stones, as well as to assess the consistency between MRCP and US findings. The study sample included 200 cases (90 males and 110 females) with symptomatic biliary system stones between 14 and 82 years. All cases underwent both the US and MRCP imaging for biliary system diagnosis. The study revealed that the most prominent age group with symptoms of biliary system stones was the 33-60-year-old group. It also found that the accuracy of US and MRCP in detecting gallbladder (GB) stones compared with the final diagnosis was 94% and 91%, respectively, with moderate conformity between their results. The accuracy of US and MRCP images in detecting common bile duct (CBD) stones was 61% and 98%, respectively, with fair conformity between their results. In addition, there is a significant agreement between the MRCP and US results in detecting the GB and CBD stones with an agreed percentage of 74% and 71%, respectively. The study concluded that US is the preferred imaging technique for patients with symptomatic gallbladder stones, whereas MRCP is a trustworthy investigation for common bile duct stones.

Diagnostic accuracy of ultrasonography compared with magnetic resonance cholangiopancreatography in the detection of choledocholithiasis.

The aim of this study is to compare the diagnostic accuracy of ultrasonography (US) with magnetic resonance cholangiopancreatography (MRCP) in the diagnosis of choledocholithiasis in context of laboratory blood test values. This retrospective study included patients who underwent both MRCP and US as part of their choledocholithiasis workup. MRCP findings, reviewed by two board-certified radiologists, laboratory findings, and US reports were collected. Our study included 243 patients. On US examination 74 cases were found dilated (30.5%), while 94 cases showed dilation (38.7%) by MRCP. The overall accuracy of US was 76.1%, where 185 patients had similar MRCP and US findings, 7.8% had false positive ultrasound, and 16% had false negative ultrasound finding. The accuracy of ultrasound was significantly higher in males (p= .013). In addition, a significant difference in duct dilatation as found by ultrasound and accuracy of diagnosis (p= .01). Although US has a relatively low accuracy, its properties of being cost-effective and non-invasive make it an ideal first step in the diagnosis of choledocholithiasis. If a patient has elevated liver enzymes or a high risk of choledocholithiasis, we recommend that MRCP be performed even no dilation was seen on US.

Evaluation of Preoperative Magnetic Resonance Cholangiopancreatography in Acute Cholecystitis to Predict Technical Difficulties in Laparoscopic Cholecystectomy.

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging technique that provides high-quality visualization of the biliary tree, including the gallbladder. This study aimed to evaluate the useful-ness of preoperative MRCP for acute cholecystitis in predicting technical difficulties during laparoscopic chole-cystectomy (LC). A total of 168 patients who underwent LC with preoperative MRCP were enrolled in this study. Patients were divided into two groups according to preoperative MRCP findings: the visualized group (n = 126), in which the entire gallbladder could be visualized; and the non-visualized group (n = 42), in which the entire gallbladder could not be visualized. The perioperative characteristics and postoperative complica-tions of the two groups were retrospectively analyzed. Operation time was longer in the non-visualized group (median 101.5 vs. 143.5 min; p < 0.001). The non-visualized group had significantly more intraoperative blood loss than the visualized group (median 5 vs. 10 g; p = 0.05). The rate of conversion to open cholecystectomy was significantly higher in the non-visualized group (1.6 vs. 9.5%; p = 0.03). In conclusion, patients in the non- visualized group showed higher difficulty in performance of LC. Our MRCP-based classification is a simple and effective means of predicting difficulties in performing LC for acute cholecystitis.

EP.TH.49The Use of MRCP to Investigate Bile Duct Stones

Abstract Aim Association of Upper Gastrointestinal Surgeons (AUGIS) latest guideline advocates stratification of patients with gallstone disease to determine their risks of common bile duct (CBD) stone and to perform Magnetic resonance cholangiopancreatography (MRCP) for those at intermediate risk. The study assessed the appropriateness of our local hospital's MRCP requests in accordance to the AUGIS standard. Method Inpatient MRCP requests for suspected ductal gallstones between June and December 2019 were identified retrospectively. Admission history, ultrasound, MRCP findings and liver function tests were collected from hospital electronic records. Patients with previous cholecystectomy were excluded. Patients were categorized into ‘low risk’, ‘intermediate risk’ and ‘high risk’. Results 67 patients were included in the study and 24 patients were discovered to have CBD stones on MRCP. The majority of patients (54%) were considered ‘intermediate risk’, whilst the ‘low risk’ group consisted of 13% of the MRCP requests and ‘high risk’ group comprised of 33%. Amongst those in the ‘low risk’ group, only 1 of 9 patients (11%) had cbd stone identified on MRCP. 19% patients in the intermediate group were found to have CBD stone, whilst 73% patients in the high risk group were identified to have CBD stone. On average, patients underwent MRCP within a day of request. Conclusion A high proportion of patients at high risk for CBD stone were referred for MRCP, contrary to AUGIS guideline. Inpatient MRCP referrals should be considered carefully in this category as it potentially increases length of stay without change in clinical management.

261 The Use of MRCP to Investigate Bile Duct Stones

Abstract Aim Association of Upper Gastrointestinal Surgeons (AUGIS) latest guideline advocates stratification of patients with gallstone disease to determine their risks of common bile duct (CBD) stone and to perform Magnetic resonance cholangiopancreatography (MRCP) for those at intermediate risk. The study assessed the appropriateness of our local hospital’s MRCP requests in accordance to the AUGIS standard. Method Inpatient MRCP requests for suspected ductal gallstones between June and December 2019 were identified retrospectively. Admission history, ultrasound, MRCP findings and liver function tests were collected from hospital electronic records. Patients with previous cholecystectomy were excluded. Patients were categorized into ‘low risk’, ‘intermediate risk’ and ‘high risk’. Results 67 patients were included in the study and 24 patients were discovered to have CBD stones on MRCP. The majority of patients (54%) were considered ‘intermediate risk’, whilst the ‘low risk’ group consisted of 13% of the MRCP requests and ‘high risk’ group comprised of 33 %. Amongst those in the ‘low risk’ group, only 1 of 9 patients (11%) had cbd stone identified on MRCP. 19% patients in the intermediate group were found to have CBD stone, whilst 73% patients in the high-risk group were identified to have CBD stone. On average, patients underwent MRCP within a day of request. Conclusions A high proportion of patients at high risk for CBD stone were referred for MRCP, contrary to AUGIS guideline. Inpatient MRCP referrals should be considered carefully in this category as it potentially increases length of stay without change in clinical management.

Analysis of Progression Time in Pancreatic Cancer including Carcinoma In Situ Based on Magnetic Resonance Cholangiopancreatography Findings.

Background: Pancreatic cancer (PC) exhibits extremely rapid growth; however, it remains largely unknown whether the early stages of PC also exhibit rapid growth speed equivalent to advanced PC. This study aimed to investigate the natural history of early PCs through retrospectively assessing pre-diagnostic images. Methods: We examined the data of nine patients, including three patients with carcinoma in situ (CIS), who had undergone magnetic resonance cholangiopancreatography (MRCP) to detect solitary main pancreatic duct (MPD) stenosis >1 year before definitive PC diagnosis. We retrospectively analyzed the time to diagnosis and first-time tumor detection from the estimated time point of first-time MPD stenosis detection without tumor lesion. Results: The median tumor size at diagnosis and the first-time tumor detection size were 14 and 7.5 mm, respectively. The median time to diagnosis and first-time tumor detection were 26 and 49 months, respectively. Conclusions: No studies have investigated the PC history, especially that of early PCs, including CIS, based on the initial detection of MPD stenosis using MRCP. Assessment of a small number of patients showed that the time to progression can take several years in the early PC stages. Understanding this natural history is very important in the clinical setting.

Prednisone-Responsive Hypercalcemia in a Patient With IgG4 Disease and Elevated Serum PTHrP Levels

Background: Ninety percent of hypercalcemia cases are related to either primary hyperparathyroidism or malignancy (1). This case presents one of the atypical etiologies of hypercalcemia. Clinical Case: A 53-year-old man with past medical history of nephrectomy was admitted for acute respiratory distress syndrome secondary to SARS-CoV-2. Hospital stay was complicated by septic shock and acute kidney injury requiring hemodialysis. Three months post hospital admission, the patient developed non-parathyroid (PTH) mediated hypercalcemia. Lab work results showed elevated serum calcium of 12.7 mg/dl (8.6–10.6), ionized calcium 6.8 mg/dl (4.2–5.4), albumin 2.6 g/dl (3.4–5.4), serum creatinine of 3.5 mg/dl (0.5–1.5), eGFR of 18.4 ml/min, and a PTH of 4 pg/ml (12–88). Liver profile - total bilirubin of 10.5 mg/dl (0–1.2), direct bilirubin of 5.9 mg/dl (0–0.2), GGTP 2055 U/L (6–60), alkaline phosphatase of 936 u/L (40–125), bone fractionated alkaline phosphatase 216 u/L (0–55), 25-OH Vitamin D of 11 ng/nl (20–80), 1,25 OH vitamin D of <5 pg/ml (19–79), TSH of 3.56 mciu/mL (0.35–4.0), CPK of 20 u/L (21–232) and a normal SPEP and immune-electrophoresisTreatment for hypercalcemia was initiated with calcitonin and oral steroids (prednisone 40mg/day for 4 days, 20mg/day for 1 day, and 10mg/day for 2 days), resulting in normalization of serum calcium. Patient received tube feedings that contained 2192 mcg retinol activity equivalents of vitamin A daily, which is associated with vitamin A intoxication in the presence of renal insufficiency. Vitamin A returned 0.78 mg/L (0.3–1.2). Serum Parathyroid hormone-related peptide (PTHrP) was elevated at 12.4 pmol/L (0.0–2.0). There was no obvious malignancy on various imaging studies. A magnetic resonance cholangiopancreatography (MRCP) showed biliary stricturing suggestive of primary sclerosing cholangitis (PSC), however, liver biopsy was not consistent with PSC. Serum IgG4 level was found to be elevated to 142 mg/dl (range: 1–123) which raised suspicion for autoimmune cholangiopathy. Discussion: Patient presented with non-PTH mediated hypercalcemia with low serum 1,25 OHD levels and elevated serum PTHrP level. Although most cases of elevated PTHrP associated with hypercalcemia are due to solid tumors, increased PTHrP levels have been seen in hypercalcemic patients with hematological malignancies and rare benign causes such as pneumonia (5). Association of elevated hypercalcemia with elevated IgG4 levels and PTHrP levels has not been previously reported. MRCP findings and abnormal morphology detailed in liver biopsy are suggestive of IgG4-related disease (IgG4RD) (3). The responsiveness in hypercalcemia to prednisone also supports this diagnosis. IgG4RD is associated with multi-organ autoimmune involvement. This case report highlights another complication of IgG4RD (i.e. hypercalcemia) associated with elevated PTHrP levels.