Intérêt de la cholangio-IRM avec perfusion de Mangafodipir Trisodium (Teslascan®) dans le diagnostic topographique et la prise en charge des fuites biliaires

The Role of the Interventional Radiologist in Bile Leak Diagnosis and Management

Bile leaks are rare but potentially devastating iatrogenic or posttraumatic complications. This is being diagnosed more frequently since the advent of laparoscopic cholecystectomy and propensity toward nonsurgical management in select trauma patients. Timely recognition and accurate characterization of a bile leak is crucial for favorable patient outcomes and involves a multimodal imaging approach. Management is driven by the type and extent of the biliary injury and requires multidisciplinary cooperation between interventional radiologists, endoscopists, and hepatobiliary/transplant surgeons. Interventional radiologists have a vital role in both the diagnosis and management of bile leaks. Percutaneous interventional procedures aid in the characterization of a bile leak and in its initial management via drainage of fluid collections. Most bile leaks resolve with decompression of the biliary system which is routinely done via endoscopic retrograde cholangiopancreaticography. Some bile leaks can be definitively treated percutaneously while others necessitate surgical repair. The primary principle of percutaneous management is flow diversion away from the site of a leak with the placement of transhepatic biliary drainage catheters. While this can be accomplished with relative ease in some cases, others call for more advanced techniques. Bile duct embolization or sclerosis may also be required in cases where a leaking bile duct is isolated from the main biliary tree.

Gadolinium-conjugated star-block copolymer polylysine-modified polyethylenimine as high-performance T 1 MR imaging blood pool contrast agents

Core-shell copolymers have received widespread attention because of their unique properties, such as suitable for surface modification and increasing the functionality. Thus, they have been increasingly used in many fields including biomedical, pharmaceutical, electronics and optics. Here, a new core-shell copolymer system was developed to synthesize potential blood pool contrast agent (CA) for magnetic resonance imaging (MRI). The novel CA with high T ₁ relaxivity was synthesized by conjugating gadolinium (Gd) chelators onto star-block copolymer polyethylenimine-grafted poly(l-lysine) (PEI-PLL) nanoparticles (NPs). The T ₁ relaxivity of PEI-PLL-DTPA-Gd NPs measured on a 7.0 T small animal MRI scanner was 8.289 mM^-1 s^-1, higher than that of T ₁ contrast agents widely used in the clinic, such as Gd-DTPA (also known as Magnevist, r ₁ = 4.273 mM^-1 s^-1). These results show that PEI-PLL-DTPA-Gd exhibits more efficient T ₁ MR contrast enhancement compared to Gd-DTPA. More importantly, the PEI-PLL-DTPA-Gd core-shell NPs exhibited extremely low toxicity when measured against the HepG2 cell line over a similar concentration rang of Magnevist. In in vivo experiments, PEI-PLL-DTPA-Gd not only displayed good T ₁ contrast enhancement for the abdominal aorta, but also showed prolonged blood circulation time compared with Gd-DTPA, which should enable longer acquisition time, for MR and MR angiographic images, with high resolution in clinical practice. PEI-PLL-DTPA-Gd NPs have potential to serve as high T ₁ relaxivity blood pool MRI CA in the clinic.

Iatrogenic hepatopancreaticobiliary injuries: a review

Iatrogenic hepatopancreaticobiliary injuries occur after various types of surgical and nonsurgical procedures. Symptomatically, these injuries may lead to a variety of clinical presentations, including tachycardia and hypotension from hemobilia or hemorrhage. Iatrogenic injuries may be identified during the intervention, immediately afterwards, or have a delayed presentation. These injuries are categorized into nonvascular and vascular injuries. Nonvascular injuries include biliary injuries such as biliary leak or stricture, pancreatic injury, and the development of fluid collections such as abscesses. Vascular injuries include pseudoaneurysms, arteriovenous fistulas, dissection, and perforation. Imaging studies such as ultrasound, computed tomography, magnetic resonance imaging, and digital subtraction angiography are critical for proper diagnosis of these conditions. In this article, we describe the clinical and imaging presentations of these iatrogenic injuries and the armamentarium of minimally invasive procedures (percutaneous drainage catheter placement, balloon dilatation, stenting, and coil embolization) that are useful in their management.

Peritoneal fluid bilirubin to serum bilirubin ratio for the diagnosis of bile leaks in orthotopic liver transplant recipients

BACKGROUND

A peritoneal fluid-to-serum bilirubin ratio (FSBR) of >5 has been shown to be accurate for the detection of bile leaks in post-cholecystectomy and trauma patients; however, there are no studies evaluating the accuracy of this threshold ratio in orthotopic liver transplant (OLT) recipients.

METHODS

We performed a nested case-control analysis to determine the optimal FSBR threshold for diagnosing bile leaks in OLT recipients and the relationship between FSBR and likelihood of bile leak. Adult OLT patients undergoing ERCP for suspected bile leak were divided into 2 groups: those with cholangiographic evidence of a bile leak and those without evidence of leak. Of 57 included patients, 37 were found to have a bile leak on cholangiogram (64.9 %).

RESULTS

We found a relationship between higher FSBR and the presence of a bile leak (OR 2.84, 95 % CI 1.37-5.88, p = 0.005). A FSBR of >3.25 produced the optimal sensitivity and specificity for identifying bile leaks in OLT recipients (area under ROC curve 0.8865, sensitivity 72.97 %, specificity 95.00 %).

CONCLUSIONS

We conclude FSBR is an easily accessible, moderately accurate test to diagnose bile leaks in liver transplant recipients. This test can inform clinical decision-making with regard to the utilization of ERCP in lower suspicion transplant recipients with a suspected bile leak.

Management of iatrogenic bile duct injuries: role of the interventional radiologist

Bile duct injuries are infrequent but potentially devastating complications of biliary tract surgery and have become more common since the introduction of laparoscopic cholecystectomy. The successful management of these injuries depends on the injury type, the timing of its recognition, the presence of complicating factors, the condition of the patient, and the availability of an experienced hepatobiliary surgeon. Bile duct injuries may lead to bile leakage, intraabdominal abscesses, cholangitis, and secondary biliary cirrhosis due to chronic strictures. Imaging is vital for the initial diagnosis of bile duct injury, assessment of its extent, and guidance of its treatment. Imaging options include cholescintigraphy, ultrasonography, computed tomography, magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography, and fluoroscopy with a contrast medium injected via a surgically or percutaneously placed biliary drainage catheter. Depending on the type of injury, management may include endoscopic, percutaneous, and open surgical interventions. Percutaneous intervention is performed for biloma and abscess drainage, transhepatic biliary drainage, U-tube placement, dilation of bile duct strictures and stent placement to maintain ductal patency, and management of complications from previous percutaneous interventions. Endoscopic and percutaneous interventional procedures may be performed for definitive treatment or as adjuncts to definitive surgical repair. In patients who are eligible for surgery, surgical biliary tract reconstruction is the best treatment option for most major bile duct injuries. When reconstruction is performed by an experienced hepatobiliary surgeon, an excellent long-term outcome can be achieved, particularly if percutaneous interventions are performed as needed preoperatively to optimize the patient's condition and postoperatively to manage complications.