Specificity Of Magnetic Resonance Cholangiography Research Articles

MRCP Vs ERCP: A Comparative Study in Diagnosis of Common Bile Duct Stones

Background: Because it is a noninvasive method, without complications, the magnetic resonance cholangiography (MRCP) is going to reliably replace ERCP in the diagnosis of pancreato-biliary diseases. Although many studies documented a high sensitivity and specificity of MRCP, its ability in detecting microlithiasis (< 5 mm in diameter) of common bile duct (CBD), responsible for acute biliary pancreatitis, is still controversial. Aim: to evaluate sensitivity, specificity, diagnostic accuracy, positive predictive value (PPV) and negative predictive value (NPV) of MRCP in diagnosis of choledocolithiasis using ERCP + endoscopic sphincterotomy (ES) as the gold standard. Patients and methods: 123 individuals, suspected for lithiasis of CBD were prospectively enrolled in the study. Clinical findings were: jaundice, fever, abdominal and/or biliary pain, weight loss with altered cholestatic enzymes (ALP > 270; Î3-GT > 50 UI/l). Patients underwent upper abdominal ultrasonography (US), then MRCP and, within 72 h, diagnostic and/or operative ERCP. All patients signed an informed consent. The statistical analysis was based on the report of true positives and negatives, false positives and negatives. Results:106/123 patients completed the study. MRCP diagnosed lithiasis of CBD in 73; did not document stones in 33. ERCP confirmed the presence of lithiasis in 66/73 pts who were submitted to ES. Seven were not found to have stones after ES. Among 33 negative pts, ERCP documented stones in 9: in 4 only after ES (it was performed according to clinico-biochemical data and to CBD dilation, though ERCP did not identify stones). The stones were 2-3 mm. In 24/33 patients negative at MRCP, ERCP confirmed this response:10/24 were submitted to ES. ES was not performed in 14/24 subjects, without CBD dilation and/or cholestasis. After a 27.8 months follow-up (range: 4-54), 8/14 remained asymptomatic, 6 underwent laparoscopic cholecystectomy without finding of CBD stones at the intra-operative cholangiography. The sensitivity, specificity, diagnostic accuracy, PPV and NPV of MRCP were: 88%, 77%, 85%, 90%, 73%. Conclusions: as MRCP has still a limitation in the diagnosis of small stones, missed at US, it leaves unrisolved the question of which patient is candidate to ERCP/ES. The recognition of microlithiasis should refer to other imaging techniques preliminar to ERCP (e.g. EUS) though their limited availability makes until now MRCP a method of choice in the diagnosis of biliary disease.

Safety and Efficacy of Endoscopic Sphincterotomy and Bile Duct Clearance in Patients with Acute Cholangitis Due to the Common Bile Duct Stones

Safety and Efficacy of Endoscopic Sphincterotomy and Bile Duct Clearance in Patients with Acute Cholangitis Due to the Common Bile Duct Stones Neven Ljubicic, Luka Rotkvic Background: It has been shown that urgent endoscopic drainage is an effective treatment for acute cholangitis and is superior to surgical drainage with a better clinical outcome Because of the risk of post-sphincterotomy bleeding in these patients many endoscopists have advocated endoscopic drainage by using nasobiliary catheter or an indwelling stent without sphincterotomy. The aim of this study was to analyze safety and efficacy of endoscopic sphincterotomy (ES) and urgent stone extraction in patients with acute cholangitis due to the common bile duct stones.Methods: Between January andDecember 2002, one hundred and eleven patients with clinical jaundice and common bile duct stones were enrolled to an ES and urgent stone extraction. ES has been performed in a standard manner, always using the guide-wire. In patients with cholangitis vigorous washing of the common bile duct has been performed after removal of the stones. Forty-six patients fulfilled criteria for acute cholangitis. Prior to the ES all patients received intravenously ciprofloxacin for at least 24 hours. Results: ES has been performed successfully in 102 (92%) patients. Complete duct clearance has been achieved in 90% of patients without cholangitis and in 93% of patients with cholangitis (not significant). Complications occurred in 12% of patients without and in 16% of those with acute cholangitis (Table). In patients with post-sphincterotomy bleeding blood transfusion was not required. The median lengths of time for resolution of jaundice in patients with and without cholangitis were similar. Significant coagulopathy has been observed in two (4.5%) patients with acute cholangitis. In those patients there were no bleeding occurred after ES. Conclusions: ES and bile duct clearance is very effective and safe method even in the patients with acute cholangitis. Mild bleeding was the most common postsphincterotomy complication not required blood transfusion even in the presence of coagulopathy. *T1500 MRCP Vs ERCP: A Comparative Study in Diagnosis of Common Bile Duct Stones Luigi T. Familiari Background: Because it is a noninvasive method, without complications, the magnetic resonance cholangiography (MRCP) is going to reliably replace ERCP in the diagnosis of pancreato-biliary diseases. Althoughmany studies documented a high sensitivity and specificity of MRCP, its ability in detecting microlithiasis ( 270; I-GT > 50 UI/l). Patients underwent upper abdominal ultrasonography (US), thenMRCP and, within 72 h, diagnostic and/or operative ERCP. All patients signed an informed consent. The statistical analysis was based on the report of true positives and negatives, false positives and negatives. Results:106/123 patients completed the study. MRCP diagnosed lithiasis of CBD in 73; did not document stones in 33. ERCP confirmed the presence of lithiasis in 66/73 pts who were submitted to ES. Seven were not found to have stones after ES.Among 33 negative pts, ERCPdocumented stones in 9: in 4 only after ES (it was performed according to clinico-biochemical data and to CBD dilation, though ERCP did not identify stones). The stones were 2-3 mm. In 24/33 patients negative at MRCP, ERCP confirmed this response:10/24 were submitted to ES. ES was not performed in 14/24 subjects, without CBD dilation and/or cholestasis. After a 27.8 months follow-up (range: 4-54), 8/14 remained asymptomatic, 6 underwent laparoscopic cholecystectomy without finding of CBD stones at the intra-operative cholangiography. The sensitivity, specificity, diagnostic accuracy, PPV and NPV of MRCP were: 88%, 77%, 85%, 90%, 73%. Conclusions: asMRCPhas still a limitation in the diagnosis of small stones,missed at US, it leaves unrisolved the question of which patient is candidate to ERCP/ES. The recognition of microlithiasis should refer to other imaging techniques preliminar to ERCP (e.g. EUS) though their limited availability makes until now MRCP a method of choice in the diagnosis of biliary disease.

Evaluation of Magnetic Resonance Cholangiography in the Management of Bile Duct Stones

Magnetic resonance cholangiography (MRC) offers the potential for accurate, noninvasive detection of common bile duct stones (CBDSs) before cholecystectomy, and for a consequent reduction in the incidence of preoperative negative diagnoses associated with endoscopic retrograde cholangiography (ERC). Prospective cohort study: MRC results were correlated with ERC (high-risk patients) or intraoperative cholangiography (moderate-risk patients). A university hospital providing primary, secondary, and tertiary care. Seventy patients with suspected CBDSs scheduled to undergo elective cholecystectomy between April 15, 1997, and September 30, 1998. Forty patients were considered at high risk and 30 at moderate risk for CBDSs, according to results of liver function tests and sonograms of the upper abdomen. Confirmation or exclusion of CBDSs by MRC was assessed by a panel of radiologists who were unaware of the ERC results. Results of ERC and intraoperative cholangiography were analyzed by the investigating gastroenterologists or surgeon. Results of MRC were positive for CBDSs in 21 (52%) of 40 high-risk patients, a finding confirmed by preoperative ERC in 19 (90%) of 21 patients. Results of MRC were positive for CBDSs in 6 (20%) of 30 moderate-risk patients, all of which were confirmed by intraoperative cholangiography. Finally, CBDSs were present in 19 (48%) of 40 high-risk patients and 6 (20%) of 30 moderate-risk patients (P = .02). Overall sensitivity and specificity of MRC were 100% and 95.6%, respectively; the positive and negative predictive values were 92.6% and 100%, respectively. Magnetic resonance cholangiography is a reliable, noninvasive method for the detection or exclusion of CBDSs, and seems to reduce the frequency of negative diagnoses associated with ERC. Magnetic resonance cholangiography revealed no CBDSs in 19 (48%) of 40 patients at high risk for CBDSs. Thus, MRC-based diagnosis has the potential to reduce the number of invasive preoperative diagnostic procedures and their associated risks and overall health care costs.

Magnetic resonance cholangiography using half-Fourier acquisition for diagnosing choledocholithiasis

Objective: Magnetic resonance cholangiography (MRC), using a half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence, noninvasively provides very rapid (1–2 s) and high-quality images of the biliary tract. We assessed the diagnostic usefulness of HASTE-MRC for choledocholithiasis. Methods: A total of 101 patients with suspected choledocholithiasis underwent MRC, ultrasonography, and endoscopic retrograde cholangiopancreatography (ERCP). In 97 patients in whom ERCP fully depicted the common bile duct, we retrospectively analyzed the capability of MRC to image the common bile duct and to diagnose choledocholithiasis, in comparison with that of ultrasonography. Results: In 34 patients, ERCP demonstrated bile duct stones, which were confirmed at endoscopic or surgical treatment. The common bile duct was fully delineated in 98% by MRC and in 70% by ultrasonography. MRC (91%) was more sensitive than ultrasonography (71%) for detecting choledocholithiasis ( p < 0.05). MRC demonstrated bile duct stones in all patients with stones ≥11 mm but missed calculi in the 29% of patients with small (3–5 mm) stones. MRC was capable of detecting choledocholithiasis regardless of bile duct caliber. The specificity of MRC (100%) was higher than that of ultrasonography (95%). Conclusion: HASTE-MRC, a fast and noninvasive procedure, can accurately diagnose choledocholithiasis although the detectability for small stones is limited.