The role of magnetic resonance cholangiopancreatography in the management of acute gallstone pancreatitis

Pilot feasibility study to determine the utility of direct access and quantitative magnetic resonance cholangiopancreatography (MRCP) in the assessment of suspected acute biliary or ductal gallstone presentations

BACKGROUND

Patients with suspected acute gallstone disease typically undergo abdominal ultrasound. MRCP is often used for patients with abnormal LFTs, potentially making ultrasound unnecessary for this group. Despite high inter-reader variability in MRCP interpretation, new AI technologies may automate and standardize detection and measurement.

METHOD

Patients with suspected acute gallstone disease and abnormal liver function tests were randomized into two diagnostic pathways, direct MRCP and standard care. Admission data, healthcare resource use, and clinical outcomes were recorded. National Health Service national 20/21 tariffs were used to calculate and compare healthcare costs. MRCP scans were subsequently analysed using MRCP + software (Perspectum Ltd).

RESULTS

27 participants were enrolled over 12 months, 15 to direct MRCP and 11 to standard care. One patient was excluded from analysis. Mean patient time to diagnostic report and mean per patient associated direct medical cost and mean cost to diagnosis for the direct MRCP and standard of care group was 2.53 days, £449.54, and £647 respectively for the direct MRCP group and 4.18 days costing £742.06 and £896 for standard care. MRCP + analysis of 11 scans showed significant differences between the groups in terms of gallbladder volume (80.2mm3 gallstone present versus 30.1mm3 without, p = 0.018 and cystic duct median width (4.6 mm gallstone present versus 2.7 mm without, p = 0.042).

CONCLUSIONS

Direct MRCP may be a feasible and potentially cost-effective diagnostic strategy for patients with suspected acute gallstone disease and deranged LFTs. Automated measurement of MRCP parameters shows promise in detecting obstruction. Larger trials are warranted to assess this potential.

CLINICAL TRIAL NUMBER

This study is registered with ClinicalTrials.gov (NCT03709030). Registration date: October 17, 2018.

Impact of Imaging Techniques in the Assessment of Gallstone Pancreatitis

From the category of biliary disease, gallstones registered an increase during the last years, approximately 6% of men and 9% of women being affected by the pathology in the United States only. In western countries between 10-20% of the adult population is suffering from cholelithiasis. Although increasing age is a major risk factor for their formation, late studies correlate gallstones appearance with an age decrease for the onset of symptoms. We therefore face a younger population manifesting pain and sometimes functional disability. In accordance with statistical analysis, the economic impact of gallstones in highly industrialized countries such as United States produces costs of up to 6.5 billion dollars annually. In this context, the appropriate timing for intervention becomes a factor of major interest. The present review uses 28 articles and specialized literature. Article selection was based on keywords and followed the effectiveness of imaging investigation such as ultrasound, CT and MRI for patients diagnosed with cholelithiasis. Since a direct comparison between the imaging investigation techniques is not concluding we have tried to establish the sensitivity and specificity offered by each imaging assessment. The comparative analysis revealed a p Kruskal-Wallis <0.001 for sensitivity and p Kruskal-Wallis=0.474 for specificity.

Acute Gallstone Pancreatitis: If a Picture Is Worth a Thousand Words, How Many Images Do We Need?

Introduction Accurate diagnosis and prompt definitive management of choledocholithiasis are vital in acute gallstone pancreatitis. The sensitivity of detection of choledocholithiasis varies across imaging modalities. Magnetic resonance cholangiopancreatography (MRCP) is the most sensitive but may not be necessary, resulting in both delayed definitive management and increased costs. We aimed to evaluate the range of radiological investigations patients with acute gallstone pancreatitis underwent and the clinical appropriateness of MRCP when performed. Methods This was an observational study of patients diagnosed with acute gallstone pancreatitis between January 1, 2019 and November 30, 2021 in a district general hospital in London, UK. A detailed review of patient records, laboratory and radiological results, and endoscopic and/or operative intervention was undertaken. Results One hundred consecutive patients diagnosed with acute gallstone pancreatitis (median age 57 years) were included. Seventy-nine had a transabdominal ultrasound (USS), 46 had CT, and 40 patients had MRCP. The median waiting time for these investigations was 1, 0, and 4 days, respectively. Choledocholithiasis was identified in 21 patients (4 on USS, 5 on CT, and 12 on MRCP). As definitive management, 37% underwent endoscopic retrograde cholangiopancreatography, and 57% underwent laparoscopic cholecystectomy. A total of 19% of patients were readmitted with pancreatitis prior to definitive management. Conclusions First-line imaging investigations such as USS and CT can detect some cases of choledocholithiasis in patients with acute gallstone pancreatitis, but not all. Despite expenses in terms of cost and length of hospital stay, MRCP remains an essential resource to detect cases of choledocholithiasis not captured by USS or CT. We recommend establishing a guideline to streamline imaging in assessing acute gallstone pancreatitis.

MR imaging for acute pancreatitis: the current status of clinical applications

Acute pancreatitis is a common clinical acute abdomen. Imaging examinations play an important role in the management of acute pancreatitis. MR imaging is a noninvasive examination with high tissue contrast and a variety of acquisition sequences that can help determine the diagnosis, complications and severity of acute pancreatitis. The acute pancreatitis classification working group modified the Atlanta classification in 2012 to improve clinical evaluations and standardize the radiologic nomenclature for acute pancreatitis. In particular, the redefinition of necrotizing pancreatitis offers a new understanding of this disease. In clinical practice, there is still a lack of unifying standards between radiologists and physicians, such as for the imaging features of pseudocysts, walled-off necrosis, peripancreatic necrosis and especially for the MR imaging features of acute pancreatitis. In this article, we review the 2012 revised Atlanta classification of acute pancreatitis and recent advances in the clinical applications of MR imaging (MRI) in acute pancreatitis by showing how MRI can provide more optimized information for clinical diagnosis and treatment plan.

Scoring System for the Management of Acute Gallstone Pancreatitis: Cost Analysis of a Prospective Study

Predicting the presence of a persistent common bile duct (CBD) stone is a difficult and expensive task. The aim of this study is to determine if a previously described protocol-based scoring system is a cost-effective strategy. The protocol includes all patients with gallstone pancreatitis and stratifies them based on laboratory values and imaging to high, medium, and low likelihood of persistent stones. The patient's stratification then dictates the next course of management. A decision analytic model was developed to compare the costs for patients who followed the protocol versus those that did not. Clinical data model inputs were obtained from a prospective study conducted at The Mount Sinai Medical Center to validate the protocol from Oct 2009 to May 2013. The study included all patients presenting with gallstone pancreatitis regardless of disease severity. Seventy-three patients followed the proposed protocol and 32 did not. The protocol group cost an average of $14,962/patient and the non-protocol group cost $17,138/patient for procedural costs. Mean length of stay for protocol and non-protocol patients was 5.6 and 7.7 days, respectively. The proposed protocol is a cost-effective way to determine the course for patients with gallstone pancreatitis, reducing total procedural costs over 12 %.

Is preoperative MRCP necessary for patients with gallstones? An analysis of the factors related to missed diagnosis of choledocholithiasis by preoperative ultrasound

Background

The diagnosis of associated choledocholithiasis prior to cholecystectomy for patients with gallstones is important for the surgical decision and treatment efficacy. However, whether ultrasound is sufficient for preoperative diagnosis of choledocholithiasis remains controversial, with different opinions on whether routine magnetic resonance cholangiopancreatography (MRCP) is needed to detect the possible presence of common bile duct (CBD) stones.

Methods

In this study, a total of 413 patients with gallstones who were admitted to the Department of General Surgery of the First Affiliated Hospital of Harbin Medical University in China for a period of 3 years and underwent both ultrasound and MRCP examinations were retrospectively analysed. After reviewing and screening these cases according to the literature, 11 indicators including gender, age, alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, indirect bilirubin, alkaline phosphatase, γ-aminotransferase, CBD diameter, and concurrent acute cholecystitis were selected and comparatively analysed.

Results

Among the 413 patients, a total of 109 cases showed concurrent gallstones and choledocholithiasis, accounting for 26.39 % of all cases. Among them, 60 cases of choledocholithiasis were revealed by ultrasound examination, accounting for 55.05 %, while 49 cases of choledocholithiasis were not detected by ultrasound examination but were confirmed by MRCP instead (the missed diagnosis rate of ultrasound was 44.95 %). The results of statistical analysis suggested that alanine aminotransferase, acute cholecystitis, and CBD diameter were the three most relevant factors for missed diagnosis by ultrasound.

Conclusion

The accuracy of preoperative ultrasonography for the diagnosis of associated CBD stones for patients with gallstones is not high. However, elevated alanine aminotransferase, concurrent acute cholecystitis, and CBD diameter were identified as key factors that may affect the accuracy of the diagnosis. Thus, routine preoperative MRCP examination is suggested for patients with gallstones to rule out possible concomitant CBD stones.