ENDOSCOPIC RETROGRADE CHOLANGIO-PANCREATOGRAPHY IN HEALTHY BEAGLES

Magnetic Resonance Cholangiopancreatography for Cholangiopancreatic Duct Imaging in Dogs

Ultrasonography is often used to diagnose biliary diseases in dogs; however, it is difficult to delineate the entire bile and pancreatic ducts. Various imaging techniques for bile and pancreatic ducts have been attempted to overcome this problem. Magnetic resonance cholangiopancreatography (MRCP) is often used to evaluate the bile and pancreatic ducts in humans with obstructive jaundice, but very few reports exist on its usage in dogs. This study was designed as a prospective observational study to assess the feasibility and effectiveness of MRCP for visualizing the bile and pancreatic ducts in nondiseased dogs. Therefore, this study aimed to evaluate the visibility of the bile and pancreatic ducts through MRCP imaging using a 3.0 T-MRI system in dogs with no signs of hepatic, biliary, and pancreatic diseases. The detection rate for each anatomical structure was evaluated, with the highest observed in the gallbladder (100%), followed by the common bile duct (80%), cystic duct (70%), pancreatic ducts in the left and right lobe of the pancreas (70%), left and right hepatic ducts (60%), accessory pancreatic ducts (60%), and major pancreatic duct (40%). MRCP is a promising noninvasive imaging technique that can promptly and accurately visualize bile and pancreatic ducts in dogs without being influenced by the skill of the operator.

Feasibility of Magnetic Resonance Cholangiopancreatography in Dogs-A Post-Mortem Study

Magnetic resonance cholangiopancreatography (MRCP) is commonly used in humans and is also feasible in cats. The aim of this post-mortem study was to investigate the feasibility of MRCP in eight adult dogs by comparing the visibility and measured diameters of the biliary tract and pancreatic ducts in MRCP with those of fluoroscopic retrograde cholangiopancreatography (FRCP) and corrosion casting. In autopsy, six dogs had no evidence of hepatobiliary disorders, one had pancreatic pathology, and one had biliary pathology. The gallbladder (GB), cystic duct, and common bile duct (CBD) were visible in the MRCP images of all eight dogs. However, the extrahepatic ducts and pancreatic ducts were only variably visible. There was statistical agreement between MRCP and FRCP in measuring the diameters of the GB (fundus and body) and CBD (at papilla and extrahepatic ducts' junction). The diameter measurements correlated between MRCP and corrosion casting. Our study showed that MRCP is feasible in dogs and allowed for proper visualization of the biliary tract. However, ducts with diameters of <1 mm were difficult to visualize using a 1.5 Tesla MRI machine. Further studies are warranted to apply MRCP in the diagnostic imaging of live dogs.

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.

Case Report: Usefulness of Drip Infusion Cholangiography With Computed Tomography for the Diagnosis of Biloma in a Dog

Bilomas are encapsulated collections of bile outside or inside the biliary tract within the abdominal cavity. For diagnostic and therapeutic approaches, it is important to identify the origin of bile leaks from the biliary tract. This case report describes the usefulness of drip infusion cholangiography with computed tomography (DIC-CT) for detecting the site of bile leakage in a dog with biloma. A 10-year-old, castrated male Pomeranian dog was referred to our department for gastrointestinal signs. Abdominal ultrasonography detected gallbladder mucocele without evidence of defect on the wall and well-defined anechoic localized fluid accumulation around the right division of the liver. On the other hand, there was only a small amount of ascites in the abdominal cavity. The accumulated fluid collected through abdominocentesis had a bilirubin concentration of 11.4 mg/dl, which was more than twice as high as that in serum (0.4 mg/dl), but had absence of pyogenic bacteria. The DIC-CT with meglumine iotroxate showed two well-defined large fluid collections: one between right medial and lateral lobe and the other between the right lateral lobe and caudate process of caudate lobe. Three-dimensional DIC-CT views that the former was enhanced by the contrast agent and that it communicated with an intrahepatic bile duct of the right lateral lobe. Moreover, the DIC-CT images confirmed communication with each fluid collections. After 6 days of hospitalization, a decrease in the amount of accumulated fluid was confirmed, after which cholecystectomy was performed. The dog was discharged from the hospital without complications. No signs of bile leakage were observed on follow-up imaging on postoperative day 10. According to authors knowledge, this has been the first report to show that DIC-CT can be useful for determining the origin of bile leakage in dogs with bilomas.

Percutaneous-endoscopic rendezvous cholangiography with biliary stent placement in a dog with extra-hepatic biliary duct obstruction

A middle-aged male springer spaniel was presented for investigation of acute vomiting, lethargy and icterus. Marked distension of the gall bladder and common bile duct was evident at ultrasound due to obstruction by mineralised intraluminal material. After 48 hours of hospitalisation with intravenous fluid therapy, analgesia and antimicrobial therapy, intervention was deemed necessary to relieve the obstruction. A percutaneous-endoscopic rendezvous approach was used to achieve placement of a pigtail stent into the distal common bile duct, successfully relieving the obstruction. Serial biochemistry measurements postprocedure confirmed marked improvements in serum bilirubin. The patient remains clinically well 24 months postprocedure, and all hepatic enzyme activities have normalised. Based on the literature search performed, this is the first successful application of this technique in the management of canine extrahepatic biliary duct obstruction.

Ultrasound-guided transhepatic computed tomography cholecystography in beagle dogs

This study was performed to evaluate the feasibility of ultrasound-guided computed tomography (CT) cholecystography and to establish an optimal protocol. In 8 healthy beagles, CT cholecystography was conducted using four contrast formulas; two dilution ratios (1:1 vs. 1:3) and two total volumes (8 mL vs. 16 mL) of 300 mgI/kg iohexol after ultrasound-guided percutaneous contrast injection into the gallbladder. CT images were obtained at 3, 10, and 30 min after injection and assessed qualitatively and quantitatively. For all contrast formulas, CT cholecystography showed the gallbladder and the intra- and extrahepatic bile ducts. The volume of the gallbladder and size of bile duct were significantly larger when using a volume of 16 mL iohexol than an 8 mL volume regardless of the dilution ratio. The distinction between the common bile duct and duodenum, the filling of the gallbladder, and the patency of bile duct were effectively assessed using a 16 mL volume of contrast agent with either dilution ratio. Beam-hardening artifacts deteriorated CT image quality for visualizing the biliary system when using the dilution ratio of 1:1. Patency of the bile tract could be easily evaluated using a curvilinear planar reconstruction. There was no significant difference in CT scan time among the different conditions. Minor leakage of contrast agent temporarily occurred after contrast injection in 30% of 32 sets of CT cholecystography. Ultrasound-guided percutaneous cholecystography can visualize both gallbladder and biliary tract with minimal artifacts using a contrast agent volume of 16 mL with a 1:3 dilution ratio.

CT cholangiography in dogs with gallbladder mucocoele

OBJECTIVES

To summarise CT cholangiography findings in dogs with gallbladder mucocoele.

MATERIALS AND METHODS

Each of 10 dogs with gallbladder mucocoele underwent CT cholangiography using meglumine iotroxate before cholecystectomy. The following structures of the biliary system were evaluated: the right and left hepatic ducts, common hepatic duct, cystic duct, common bile duct and gallbladder.

RESULTS

The hepatic duct, cystic duct, common bile duct and gallbladder were imaged by contrast-enhanced CT cholangiography. The passage of the contrast medium through the bile duct into the duodenum was visible in nine dogs. The curved planar reformation images of two dogs showed they had filling defects in the bile duct system. In one dog with hyperbilirubinaemia due to chronic hepatitis, the bile duct system was not completely contrast-enhanced. Surgical exploration revealed no evidence of common bile duct obstruction in any dog.

CLINICAL SIGNIFICANCE

CT cholangiography delineates the structural characteristics of the biliary system and partially estimates its patency in dogs with gallbladder mucocoele. Therefore this procedure may be useful as a preoperative screen of the bile duct system in dogs with gallbladder mucocoele.

Gallbladder Agenesis in 17 Dogs: 2006-2016

Background

Gallbladder agenesis (GBA) is extremely rare in dogs.

Hypothesis/Objectives

To describe the history, clinical signs, diagnosis, treatment, and outcomes of dogs with GBA.

Animals

Seventeen client‐owned dogs with GBA.

Methods

Medical records from 2006 through 2016 were retrospectively reviewed. Dogs were included when GBA was suspected on abdominal ultrasonography and confirmed by gross evaluation. Signalment, clinical signs, clinicopathological data, diagnostic imaging, histopathology, treatment, and outcome were recorded.

Results

Dogs were of 6 different breeds, and Chihuahuas (10 of 17) were most common. Median age at presentation was 1.9 (range, 0.7–7.4) years. Clinical signs included vomiting (5 of 17), anorexia (2 of 17), ascites (2 of 17), diarrhea (1 of 17), lethargy (1 of 17), and seizures (1 of 17). All dogs had increased serum activity of at least 1 liver enzyme, most commonly alanine aminotransferase (15 of 17). Fifteen dogs underwent computed tomography (CT) cholangiography; common bile duct (CBD) dilatation was confirmed in 12, without evidence of bile duct obstruction. Gross evaluation confirmed malformation of the liver lobes in 14 of 17 dogs and acquired portosystemic collaterals in 5 of 17. Ductal plate malformation was confirmed histologically in 16 of 17 dogs. During follow‐up (range, 4–3,379 days), 16 of 17 dogs remained alive.

Conclusions and Clinical Importance

Dogs with GBA exhibit clinicopathological signs of hepatobiliary injury and hepatic histopathological changes consistent with a ductal plate abnormality. Computed tomography cholangiography was superior to ultrasound examination in identifying accompanying nonobstructive CBD distention. Computed tomography cholangiography combined with laparoscopic liver biopsy is the preferable approach to characterize the full disease spectrum accompanying GBA in dogs.

Advances in Flexible Endoscopy

Flexible endoscopy, a minimally invasive diagnostic and potentially therapeutic tool, has become more available over the past decades. A fiberscope is used to visualize the lumen of the area of interest and collect tissue or fluid samples for evaluation. Samples can be submitted for histopathology, cytologic analysis, and bacterial culture. Flexible endoscopy is being investigated. This article provides a brief review of equipment and basic flexible endoscopy followed by an overview of advanced flexible endoscopic procedures that focuses on the gastrointestinal tract. The procedures included here may become more readily available and improve diagnosis and treatment.

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.

Diagnosis of pancreatitis in dogs and cats

Pancreatitis is the most common disorder of the exocrine pancreas in both dogs and cats. Ante-mortem diagnosis of canine and feline pancreatitis can be challenging. The clinical picture of dogs and cats with pancreatitis varies greatly (from very mild to severe or even fatal) and is characterised by non-specific findings. Complete blood count, serum biochemistry profile and urinalysis should always be performed in dogs and cats suspected of having pancreatitis, although findings are not-specific for pancreatitis. Serum amylase and lipase activities and trypsin-like immunoreactivity (TLI) concentrations have no or only limited clinical value for the diagnosis of pancreatitis in either dogs or cats. Conversely, serum pancreatic lipase immunoreactivity (PLI) concentration is currently considered to be the clinicopathological test of choice for the diagnosis of canine and feline pancreatitis. Abdominal radiography is a useful diagnostic tool for the exclusion of other diseases that may cause similar clinical signs to those of pancreatitis. Abdominal ultrasonography can be very useful for the diagnosis of pancreatitis, but this depends largely on the clinician's experience. Histopathological examination of the pancreas is considered the gold standard for the diagnosis and classification of pancreatitis, but it is not without limitations. In clinical practice, a combination of careful evaluation of the animal's history, serum PLI concentration and abdominal ultrasonography, together with pancreatic cytology or histopathology when indicated or possible, is considered to be the most practical and reliable means for an accurate diagnosis or exclusion of pancreatitis compared with other diagnostic modalities.

Feasibility of percutaneous contrast ultrasound-guided cholecystography in dogs

Differentiating hepatocellular disease versus biliary obstruction can be challenging in dogs presented for icterus. The purpose of this prospective study was to determine the feasibility of percutaneous contrast ultrasound-guided cholecystography in dogs. Ten normal dogs weighing 7.6-13.0 kg (median 9.8 kg) were recruited. All dogs were considered normal based on complete blood count, serum chemistry profile, ultrasound examination, and percutaneous radiographic cholecystography. Percutaneous contrast ultrasound-guided cholecystography was performed using 0.5 ml of commercially available contrast agent and two conventional ultrasound machines for simultaneous scanning at two different locations. Two observers independently evaluated the time to initial detection of contrast in the proximal duodenum and duration of contrast enhancement via visual monitoring. Dynamic contrast enhancement was calculated using time-intensity curves. Mean (± SD) and median (range) of time to initial detection were 8.60 s (± 3.35) and 8.0 s (2.0-11.0), respectively, and mean and median duration were 50.45 s (± 23.24) and 53.0 s (20.0 - 70.0), respectively. Mean, median, and range of peak intensity were 114.1 mean pixel value (MPV) (SD ± 30.7), 109.2 MPV, and 79.7-166.7, respectively, and mean, median, and range of time to peak intensity were 26.1 s (SD ± 7.1 s), 24.0 s, and 19.0-41.0 s, respectively. Findings indicated that percutaneous contrast ultrasound-guided cholecystography is a feasible technique for detecting and quantifying patency of the bile duct in normal dogs. Future studies are needed to assess the diagnostic utility of this technique for dogs with biliary obstruction.

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.

Choledochal tube stenting for decompression of the extrahepatic portion of the biliary tract in dogs: 13 cases (2002–2005)

OBJECTIVE

To determine clinicopathologic features, surgical management, complications, and long-term outcome associated with diseases of the extrahepatic portion of the biliary tract treated via choledochal stent placement in dogs.

DESIGN

Retrospective case series.

ANIMALS

13 dogs.

PROCEDURE

Data were obtained from medical records, and follow-up information was obtained via reexamination or telephone interview with owners or referring veterinarians.

RESULTS

10 dogs had extrahepatic biliary obstruction (EHBO), 6 as a result of pancreatitis. Two dogs had rupture of the common bile duct associated with cholelithiasis. In 1 dog, a stent was placed prophylactically after gastroduodenostomy was performed for a perforated duodenal ulcer. Nine of 13 dogs survived the perioperative period and were discharged. No recurrence of EHBO or other complications developed in the discharged dogs while the stents were in place. Median follow-up period from surgery to last owner contact was 13.3 months. In 1 dog, the stent was removed endoscopically 10 months after surgery and EHBO recurred 9 months after stent removal because of cholangitis. In 4 of 5 dogs that were discharged from the hospital, in which the fate of the stent could be confirmed and the stent was secured to the duodenal wall with absorbable suture materials, the stents were passed in the feces 1 to 11 months after surgery.

CONCLUSIONS AND CLINICAL RELEVANCE

Choledochal tube stenting is an effective method of decompression of the extrahepatic portion of the biliary tract in dogs and provides a less complex alternative to traditional cholecystoenterostomy techniques in select cases.

ENDOSCOPIC RETROGRADE CHOLANGIO-PANCREATOGRAPHY IN DOGS WITH CHRONIC GASTROINTESTINAL PROBLEMS

Endoscopic retrograde cholangio-pancreatography is a combination of endoscopy and fluoroscopy used for radiographic imaging of the biliary and pancreatic ducts. In order to assess its feasibility and to describe abnormal findings in dogs, this technique was performed in 30 dogs with nonspecific chronic gastrointestinal disturbances. Using an 11-mm side-view endoscope, retrograde cholangiography was successful in 20/30 dogs (67%) and pancreatography in 21/30 (70%). Success was affected by intraduodenal food, mucus or blood, problems in papillary cannulation, stomach overdistention, body size, and changes in duodenal mucosa. It was impossible to perform the procedure in dogs weighing < 10 kg with the available material. Endoscopic retrograde cholangiography revealed findings that differed from previous reports in healthy beagles in 5/20 dogs. Findings included enlarged common bile duct (n = 2), intraductal filling defects (n = 2), and deviated course of common bile duct (n = 1), and major papilla stenosis (n = 1). In the dog with major papilla stenosis and intraductal filling defects, endoscopic guided sphincterotomy was performed. Endoscopic retrograde pancreatography revealed an abnormal course of the accessory pancreatic duct in 2/21 dogs. In both dogs with proven end-stage pancreatic acinar atrophy, the left duct branch did not run distal the stomach to the left but went parallel to the right duct branch and the duodenum. Repeated clinical and laboratory examinations revealed no signs of complications after endoscopic retrograde cholangio-pancreatography. It was concluded that this imaging technique is promising for the diagnosis of biliary and pancreatic diseases in dogs. It also offers the chance for new treatment options such as endoscopic guided sphincterotomy in dogs.