Imaging of Von Meyenburg complexes.

Von Meyenburg complexes, or biliary hamartomas, are frequently incidentally detected. They are usually easy to characterize with magnetic resonance imaging. However, in some occasions they are difficult to differentiate from other liver lesions, in particular from small liver metastases. Von Meyenburg complexes are developmental malformations of the ductal plate. They can be found in association with Caroli disease and Caroli syndrome. Like other ductal plate malformations, Von Meyenburg complexes associated with cholangiocarcinoma have been described and their relationship has been established. This review provides an update on the etiopathogenesis of Von Meyenburg complexes, illustrates the imaging features on ultrasound, CT and MRI of this condition and discusses the most common diagnostic pitfalls. The relationships between Von Meyenburg complexes and the various ductal plate malformations and the most recent literature data regarding the relationships between Von Meyenburg complexes and cholangiocarcinoma are presented.

Transcatheter arterial embolization for acute nonvariceal upper gastrointestinal bleeding: Indications, techniques and outcomes.

Over the past three decades, transcatheter arterial embolization has become the first-line therapy for the management of acute nonvariceal upper gastrointestinal bleeding that is refractory to endoscopic hemostasis. Advances in catheter-based techniques and newer embolic agents, as well as recognition of the effectiveness of minimally invasive treatment options, have expanded the role of interventional radiology in the treatment of bleeding for a variety of indications. Transcatheter arterial embolization is a fast, safe, and effective minimally invasive alternative to surgery, when endoscopic treatment fails to control acute bleeding from the upper gastrointestinal tract. This article describes the role of arterial embolization in the management of acute nonvariceal upper gastrointestinal bleeding and summarizes the literature evidence on the outcomes of endovascular therapy in such a setting.

Transjugular intrahepatic portosystemic shunt for acute variceal gastrointestinal bleeding: Indications, techniques and outcomes.

Acute variceal bleeding is a life-threatening condition that requires a multidisciplinary approach for effective therapy. The transjugular intrahepatic portosystemic shunt (TIPS) procedure is a minimally invasive image-guided intervention used for secondary prevention of bleeding and as salvage therapy in acute bleeding. Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy fail, before the clinical condition worsens. Furthermore, admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively. This procedure involves establishment of a direct pathway between the hepatic veins and the portal veins to decompress the portal venous hypertension that is the source of the patient's bleeding. The procedure is technically challenging, especially in critically ill patients, and has a mortality of 30%-50% in the emergency setting, but has an effectiveness greater than 90% in controlling bleeding from gastro-esophageal varices. This review focuses on the role of TIPS in the setting of variceal bleeding, with emphasis on current indications and techniques for TIPS creation, TIPS clinical outcomes, and the role of adjuvant embolization of varices.

Anatomy of liver arteries for interventional radiology.

The availability of intra-arterial hepatic therapies (radio and/or chemo-embolisation, intra-arterial hepatic chemotherapy) has convinced radiologists to perfect their knowledge of the anatomy of the liver arteries. These sometimes, complex procedures most often require selective arterial catheterization. Knowledge of the different arteries in the liver and the peripheral organs is therefore essential to optimize the procedure and avoid eventual complications. This paper aims to describe the anatomy of the liver arteries and the variants, applying it to angiography images, and to understand the implications of such variations in interventional radiological procedures.

Current role of transcatheter arterial embolization for bladder and prostate hemorrhage.

Intractable hematuria from the bladder or the prostate can be life-threatening and its management remains a difficult clinical problem. Severe bleeding can arise as a result of radiation cystitis, bladder carcinoma, cyclophosphamide-induced cystitis, severe infection, transurethral resection of the prostate and prostate cancer. When irrigation of the bladder through a three-way catheter and fulguration of the bleeding lesions fail to stop the hematuria, a life-threatening situation can develop, when blood transfusion fails to keep pace with the rate of blood loss. Patients with massive uncontrollable hematuria are often elderly and unfit for cystectomy as a treatment. Many urologists have had to manage this difficult problem, and several different treatments have been attempted and described, with varying degrees of success. Transcatheter arterial embolization of the vesical or prostatic arteries is occasionally indicated in these patients when all other measures have failed. There is limited published experience with this procedure, but success in 90% of patients is reported when the vesical or prostatic arteries can be identified. The aim of this review is to describe the current place of transcatheter arterial embolization in the management of severe bladder or prostate bleeding after failed conservative therapy, and to review its efficacy and morbidity.

Liver segmentation: practical tips.

The liver segmentation system, described by Couinaud, is based on the identification of the three hepatic veins and the plane passing by the portal vein bifurcation. Nowadays, Couinaud's description is the most widely used classification since it is better suited for surgery and more accurate for the localisation and monitoring of intra-parenchymal lesions. Knowledge of the anatomy of the portal and venous system is therefore essential, as is knowledge of the variants resulting from changes occurring during the embryological development of the vitelline and umbilical veins. In this paper, the authors propose a straightforward systematisation of the liver in six steps using several additional anatomical points of reference. These points of reference are simple and quickly identifiable in any radiological examination with section imaging, in order to avoid any mistakes in daily practice. In fact, accurate description impacts on many diagnostic and therapeutic applications in interventional radiology and surgery. This description will allow better preparation for biopsy, portal vein embolisation, transjugular intrahepatic portosystemic shunt, tumour resection or partial hepatectomy for transplantation. Such advance planning will reduce intra- and postoperative difficulties and complications.