Endoscopic ultrasonography-guided placement of a transhepatic portal vein stent in a live porcine model

Interventional Endoscopic Ultrasound: Current Status and Future Frontiers

Interventional endoscopic ultrasound has fueled remarkable advancements in the field of therapeutic procedures, revolutionizing minimally invasive interventions for a diverse range of conditions. This review highlights the latest breakthroughs and advancements in therapeutic endoscopic ultrasound, showcasing its potential to transform patient care.

Endoscopic ultrasound-guided vascular interventions: An expanding paradigm

Endoscopic ultrasound (EUS) has expanded its arena from a mere diagnostic modality to an essential therapeutic tool in managing gastrointestinal (GI) diseases. The proximity of the GI tract to the vascular structures in the mediastinum and the abdomen has facilitated the growth of EUS in the field of vascular interventions. EUS provides important clinical and anatomical information related to the vessels' size, appearance and location. Its excellent spatial resolution, use of colour doppler with or without contrast enhancement and ability to provide images “real-time” helps in precision while intervening vascular structures. Additionally, structures such as venous collaterals or varices can be dealt with optimally using EUS. EUS-guided vascular therapy with coil and glue combination has revolutionized the management of portal hypertension. It also helps to avoid radiation exposure in addition to being minimally invasive. These advantages have led EUS to become an upcoming modality to complement traditional interventional radiology in the field of vascular interventions. EUS-guided portal vein (PV) access and therapy is a new kid on the block. EUS-guided portal pressure gradient measurement, injecting chemotherapy in PV and intrahepatic portosystemic shunt has expanded the horizons of endo-hepatology. Lastly, EUS has also forayed into cardiac interventions allowing pericardial fluid aspiration and tumour biopsy with experimental data on access to valvular apparatus. Herein, we provide a comprehensive review of the expanding paradigm of EUS-guided vascular interventions in GI bleeding, portal vein access and its related therapeutic interventions, cardiac access, and therapy. A synopsis of all the technical details involving each procedure and the available data has been tabulated, and the future trends in this area have been highlighted.

Diagnostic and interventional EUS in hepatology: An updated review

EUS has become an increasingly used diagnostic and therapeutic modality in the armamentarium of endoscopists. With ever-expanding indications, EUS is being used in patients with liver disease, for both diagnosis and therapy. EUS is playing an important role in providing additional important information to that provided by cross-sectional imaging modalities such as computerized tomography and magnetic resonance imaging. Domains of therapy that were largely restricted to interventional radiologists have become accessible to endosonologists. From liver biopsy and sampling of liver lesions to ablative therapy for liver lesions and vascular interventions for varices, there is increased use of EUS in patients with liver disease. In this review, we discuss the various diagnostic and therapeutic applications of EUS in patients with various liver diseases.

Role of endoscopic ultrasound in anticancer therapy: Current evidence and future perspectives

The digestive system is one of the most common sites of malignancies in humans. Since gastrointestinal tumors represent a massive global health burden both in terms of morbidity and health care expenditures, scientists continuously develop novel diagnostic and therapeutic methods to ameliorate the detrimental effects of this group of diseases. Apart from the well-established role of the endoscopic ultrasound (EUS) in the diagnostic course of gastrointestinal and hepatobiliary malignancies, we have recently become acquainted with a vast array of its therapeutic possibilities. A multitude of previously established, evidence-based methods that might now be guided by the EUS emerged: Radiofrequency ablation, brachytherapy, fine needle injection, celiac plexus neurolysis, and endoscopic submucosal dissection. In this review we endeavored to provide a comprehensive overview of the role of these methods in different malignancies of the digestive system, primarily in the treatment and symptom control in pancreatic cancer, and additionally in the management of hepatic, gastrointestinal tumors, and pancreatic cysts.

Role of endoscopic ultrasound in the field of hepatology: Recent advances and future trends

The role of endoscopic ultrasound (EUS) as a diagnostic and therapeutic modality for the management of various gastrointestinal diseases has been expanding. The imaging or intervention for various liver diseases has primarily been the domain of radiologists. With the advances in EUS, the domain of endosonologists is rapidly expanding in the field of hepatology. The ability to combine endoscopy and sonography in one hybrid device is a unique property of EUS, together with the ability to bring its probe/transducer near the liver, the area of interest. Its excellent spatial resolution and ability to provide real-time images coupled with several enhancement techniques, such as contrast-enhanced (CE) EUS, have facilitated the growth of EUS. The concept of “Endo-hepatology” encompasses the wide range of diagnostic and therapeutic procedures that are now gradually becoming feasible for managing various liver diseases. Diagnostic advancements can enable a wide array of techniques from elastography and liver biopsy for liver parenchymal diseases, to CE-EUS for focal liver lesions to portal pressure measurements for managing various liver conditions. Similarly, therapeutic advancements range from EUS-guided eradication of varices, drainage of bilomas and abscesses to various EUS-guided modalities of liver tumor management. We provide a comprehensive review of all the different diagnostic and therapeutic EUS modalities available for the management of various liver diseases. A synopsis of all the technical details involving each procedure and the available data has been tabulated, and the future trends in this area have been highlighted.

Endoscopic ultrasound guided hepatic interventions

Intervention for liver disease has predominantly been performed through the percutaneous approach. However, as endoscopic ultrasound (EUS) applications have expanded, there have emerged various EUS-guided interventions for liver disease, a space we call "Endo-Hepatology". EUS-guided liver biopsy can be considered the "forerunner" of Endo-Hepatology and has become a clinical option for patients requiring histologic diagnosis and staging of their liver disease. EUS also enables direct access to the portal vein. Subsequently, many procedures are being explored, such as angiography, measurement of the portosystemic pressure gradient, portal vein sampling to detect cancer cell or DNA, and EUS-guided transhepatic intrahepatic portosystemic shunt creation. Since the transducer is close to the liver, especially the left and caudate lobes, EUS can be used as a rescue when the percutaneous approach is not favorable and EUS-guided treatments of liver tumor, cyst and abscess have been reported. This review summarizes the available studies of EUS-guided intervention in the liver.

Feasibility and safety of EUS-guided selective portal vein embolization with a coil and cyanoacrylate in a live porcine model

Background and Objectives:

Preoperative portal vein (PV) embolization using the percutaneous transhepatic approach has been performed in patients with hepatobiliary malignancy before extensive liver resection. The aim of this study is to evaluate the technical feasibility and initial safety of EUS-guided selective PV embolization using a coil and cyanoacrylate in a live porcine model.

Methods:

EUS-guided selective intrahepatic PV embolization with a coil and cyanoacrylate was performed in 9 pigs. The selected PV was punctured with 19G fine-needle aspiration (FNA) needle, and the coil was inserted under EUS-guidance. The cyanoacrylate was then immediately injected through the same FNA needle. The blood flow change in the embolized PV was evaluated using color Doppler EUS. A necropsy was performed following the 1-week observation period.

Results:

The success rates for the coil and cyanoacrylate delivery were 88.9% (8/9) and 87.5% (7/8), respectively. In 1 case, the coil migrated into the hepatic parenchyma. In another case, the cyanoacrylate injection failed due to early clogging in the FNA needle. There was a complete blockage of blood flow confirmed by color Doppler EUS in the embolized PV after coil and cyanoacrylate treatment. There was coil migration into the hepatic parenchyma in 1 case. There was no animal distress observed during the 1-week observation period before necropsy. The necropsy showed no evidence of damage to the intra-abdominal organs, and the selected PV was totally occluded with embolus.

Conclusion:

The study findings indicate EUS-guided selective PV embolization is both technically feasible and initially safe in an animal model.

Endoscopic Ultrasound-Guided Vascular Therapy: The Present and the Future

Endoscopic ultrasound (EUS) offers access to many intra-abdominal vessels that until now have only been accessible to the surgeon and interventional radiologist. In addition to assisting with diagnostics, this unique access offers the potential for therapeutic intervention for a host of indications. To date, this has had the most clinical impact in the treatment of gastroesophageal varices, with EUS-guided coil and glue application growing in use worldwide. Although randomised controlled trial data is lacking, we discuss the growing body of literature behind EUS-guided therapy in the management of varices. EUS has also been used in specialized centres to assist in non-variceal gastrointestinal bleeding. The treatment of bleeding from Dieulafoy lesions, tumours and pancreatic pseudoaneurysms has all been described. The potential applications of EUS have also extended to the placement of portal vein stents and porto-systemic shunts in animal models. As medicine continues to move to increasingly less invasive interventions, EUS-guided therapies offer substantial promise for the safe and effective delivery of targeted treatment for a widening array of vascular disorders.