Cholangiopancreatography in cats: a post-mortem comparison of MRI with fluoroscopy, corrosion casting and histopathology.

In human medicine, magnetic resonance cholangiopancreatography (MRCP) is a valuable diagnostic tool for hepatobiliary and pancreatic diseases. In veterinary medicine, however, data evaluating the diagnostic value of MRCP are limited. The primary objectives of this prospective, observational, analytical investigation were to assess whether MRCP reliably visualizes the biliary tract and pancreatic ducts in cats without and with related disorders, and whether MRCP images and measurements of the ducts agree with those of fluoroscopic retrograde cholangiopancreatography (FRCP), corrosion casting and histopathology. A secondary objective was to provide MRCP reference diameters for bile ducts, GB, and pancreatic ducts. Donated bodies of 12 euthanized adult cats underwent MRCP, FRCP, and autopsy with corrosion casting of the biliary tract and pancreatic ducts using vinyl polysiloxane. Diameters of the biliary ducts, gallbladder (GB), and pancreatic ducts were measured using MRCP, FRCP, corrosion casts and histopathologic slides. There was an agreement between MRCP and FRCP in measuring diameters of the GB body, GB neck, cystic duct, and common bile duct (CBD) at papilla. Strong positive correlations existed between MRCP and corrosion casting for measuring GB body and neck, cystic duct, and CBD at the extrahepatic ducts' junction. In contrast to the reference methods, post-mortem MRCP did not visualize right and left extrahepatic ducts, and pancreatic ducts in most cats. Based on this study, MRCP with 1.5 Tesla can be regarded as a contributory method to improve the assessment of feline biliary tract and pancreatic ducts when their diameter is >1 mm.

Diagnostic value of endoscopic retrograde cholangiopancreatography and therapeutic value of endoscopic sphincterotomy in dogs with suspected hepatobiliary disorders.

BACKGROUND: Conventional diagnostic methods have some limitations in diagnosing specific causes of canine hepatobiliary disorders. In the evaluation of the hepatobiliary system in dogs, ultrasonography (US) is the first imaging method of choice. Nonetheless, endoscopic retrograde cholangiopancreatography (ERCP) has also been proven to be a practicable technique for evaluating canine hepatobiliary (endoscopic retrograde cholangiography, ERC) and pancreatic duct (endoscopic retrograde pancreatography, ERP) disorders, providing additional therapeutic options by sphincterotomy (EST). To date, the efficacy and safety of diagnostic and therapeutic ERCP has not been evaluated in veterinary medicine literature. The present study sought to report complications and outcomes of dogs undergoing ERCP and EST, and to assess the usefulness of diagnostic ERCP by comparing the findings of US, ERCP and histopathological findings in liver and pancreas. RESULTS: This retrospective case series comprises data collected from 15 dogs that underwent successful ERC/ERCP. Nine dogs underwent EST following ERC. US and ERC were best in agreement when assessing the common bile duct. In case of disagreement between the modalities, the ERC findings of the ductal structures were in line with the available pathology findings more often than the US findings, whereas the opposite was noted for the gallbladder. The technical success rates were 88.2% for ERC, 66.7% for ERP, and 81.8% for EST, with no major complications during or immediately after the procedure. Immediate bile flow after EST was recorded in 7/9 dogs but only four showed coinciding clinical and laboratory improvement and four dogs were euthanized within 1-6 days after EST. CONCLUSIONS: US remains a valuable initial diagnostic imaging method for hepatobiliary disorders and allows good assessment of the gallbladder. ERC can serve as a complementary procedure for diagnostic assessment of the hepatobiliary duct disorders. However, in order to improve the outcomes of EST, careful selection of patients for the procedure would require more advanced diagnostic imaging of the hepatobiliary area.

Initial experience with endoscopic retrograde cholangiography and endoscopic retrograde biliary stenting for treatment of extrahepatic bile duct obstruction in dogs.

OBJECTIVE: To describe techniques for endoscopic retrograde cholangiography (ERC) and endoscopic retrograde biliary stenting of the common bile duct (CBD) for minimally invasive treatment of extrahepatic bile duct obstruction (EHBDO) in dogs. DESIGN: Experimental study and clinical report. ANIMALS: 7 healthy research dogs and 2 canine patients. PROCEDURES: ERC and endoscopic retrograde biliary stenting were performed in healthy purpose-bred research dogs and client-owned dogs with a diagnosis of EHBDO that underwent an attempted biliary stent procedure. Research dogs were euthanized after completion of the procedure and underwent necropsy. With dogs under general anesthesia, the pylorus was cannulated with a side-view duodenoscope, and the duodenum was entered. The major duodenal papilla (MDP) and minor duodenal papilla were then identified, and the MDP was cannulated. Endoscopic retrograde cholangiography and endoscopic retrograde biliary stenting were attempted with the aid of endoscopy and fluoroscopy in all dogs. Procedure time, outcome for duodenal and MDP cannulation, and success of stent placement were recorded. RESULTS: Endoscopic retrograde cholangiography was successfully performed in 5 of 7 research dogs and in 1 of 2 patients. Biliary stenting was achieved in 4 of 7 research dogs and 1 of 2 patients, with a polyurethane (n = 4) or self-expanding metallic stent (1). One patient had a mass such that visualization of the MDP was impossible and no attempt at biliary cannulation could be made. After placement, stent patency was documented by means of contrast cholangiography and visualization of biliary drainage into the duodenum intra-operatively. No major complications occurred during or after the procedure in any patient. Follow-up information 685 days after stent placement in 1 patient provided evidence of biliary patency on serial repeated ultrasonography and no evidence of complications. CONCLUSIONS and CLINICAL RELEVANCE: ERC and endoscopic retrograde biliary stenting were successfully performed in a small group of healthy dogs and 1 patient with EHBDO, but were technically challenging procedures. Further investigation of this minimally invasive technique for the treatment of EHBDO in dogs is necessary before this may be considered a viable alternative to current treatment methods.

Feasibility of endoscopic retrograde cholangiopancreatography in healthy cats.

Cats are predisposed to diseases of the biliary tract and the exocrine pancreas and these can be challenging to diagnose. In humans and dogs > 10 kg, endoscopic retrograde cholangiopancreatography (ERCP) has been successfully used to diagnose some of these disorders. The purpose of our study was to determine whether ERCP would also be feasible in cats using a pediatric duodenoscope. Four purpose-bred, clinically healthy, castrated domestic shorthair cats participated in two studies. Study 1 compared standard white light endoscopy with chromoendoscopy for localizing the major duodenal papilla. In Study 2 ERCP was performed. Repeated clinical examinations and measurements of serum feline pancreatic lipase immunoreactivity (fPLI) were performed before and up to 18 hours after interventions on all cats. Chromoendoscopy was subjectively judged to be superior for localizing the major papilla. Insertion of the ERCP catheter was best accomplished when cats were in dorsal recumbency. Complete ERCP was successful in two cats. In the other cats, either retrograde cholangiography or pancreatography was possible. Serum fPLI concentrations increased temporarily in two cats during Study 2 when measured immediately, 2, 4, and 18 h after ERCP. Peak fPLI concentrations were detected either immediately after ERCP or 2 h later. No clinical signs of complications were observed within 18 h after the procedures. Findings indicated that ERCP is technically demanding but feasible in healthy cats. Future studies need to determine whether the temporary increases in serum fPLI concentrations are clinically important and to investigate the utility of ERCP in feline patients.

Magnetic resonance (MR) imaging and MR cholangiopancreatography findings in cats with cholangitis and pancreatitis.

Cholangiohepatitis/cholangitis is second only to hepatic lipidosis as the most common liver disease in cats and is often associated with concurrent pancreatitis. Magnetic resonance imaging (MRI) and MR cholangiopancreatography (MRCP) have developed into an accurate, highly sensitive and specific imaging tool for the diagnosis of biliary and pancreatic duct disorders in humans. In this prospective case series, 10 cats with suspected cholangitis and/or pancreatitis were enrolled based on clinical history, physical examination and appropriate diagnostic test results. MRI and MRCP sequences with secretin stimulation of the cranial abdomen were performed, and sonography and laparoscopic biopsies for histologic diagnosis were obtained for comparison. MRI detected pancreatic abnormalities in cats suspected of pancreatitis, including T1 pre-contrast hypointense and T2 hyperintense pancreatic parenchyma and a dilated pancreatic duct. The MRI findings of the liver were non-specific. Nine of 10 cats had biliary abnormalities, including gall bladder wall thickening, gall bladder wall moderate contrast enhancement and/or gall bladder debris. Eight of 10 cats had histologic evidence of pancreatitis, as well as hepatitis or cholangitis, with one cat diagnosed with hepatic lymphoma. The advantages of MRI/MRCP over sonography of these cats included the striking pancreatic signal changes associated with pancreatitis and the ability to comprehensibly assess and measure the pancreas and hepatobiliary structures without operator dependence or interference from bowel gas. MRI/MRCP imaging of the feline abdomen may be beneficial in cases with equivocal ultrasound imaging findings.

Endoscopic retrograde cholangio-pancreatography in healthy Beagles.

Endoscopic retrograde cholangiography and pancreatography was performed in seven healthy Beagles to assess the common bile duct and the accessory pancreatic duct after retrograde filling with an iodine contrast medium. All dogs had a major and a minor duodenal papilla. One Beagle had additionally an accessory papilla. The diameter of the contrast filled ducts was measured at three defined measure points (MP1-3) in ventrodorsal radiographs and left lateral radiographs. In ventrodorsal radiographs of endoscopic retrograde cholangiography the common bile duct had a straight craniomedial course. The mean duct diameter was from proximal to distal 3.04 +/- 1.89mm at MP1, 2.38 +/- 1.23 mm at MP2, and 2.11 +/- 0.84 mm at MP3. In ventrodorsal radiographs of endoscopic retrograde pancreatography, the left and right branch of the accessory pancreatic duct united in the pancreatic body. The mean diameter of the right branch was 0.88 +/- 0.14 mm at MP1, 0.72 +/- 0.2 mm at MP2 and 0.61 +/- 0.11 mm at MP3. The left branch had a diameter of 0.93 +/- 0.28 mm at MP1, 0.86 +/- 0.21 at MP2, and 0.6 +/- 0.07 mm at MP3. The mean length was 81.6 +/- 14.3 mm for the right and 107.0 +/- 24.9mm for the left branch. In left lateral radiographs of endoscopic retrograde pancreatography, it was not possible to differentiate the left from the right branch. Both branches ran nearly parallel and showed similar diameters but slight differences in length. The study proves that endosopic retrograde cholangio-pancreatography is possible in dogs. Radiographs taken from dogs in dorsal recumbency allow an objective assessment of the common bile duct and the accessory pancreatic duct.