| BackgroundHypersplenism and oesophageal variceal bleeding are the two most manifestations of portal hypertension complicited with liver cirrhosis. Splenectomy and partial splenic embolization (PSE) were commonly used to treat hypersplenism. However, splenectomy impaired the immune function, as well as resulting in high morbidity and mortality rate. PSE is a minimally invasive approach that could conserve partial function of spleen, but it also has its limitiations and complications such as splenic abscess. Over the past decade, there have radical alterations in management of variceal haemorrhage in patients with portal hypertension, pharmacological treatment and endoscopic variceal sclerotherapy or variceal ligation have been advocated as first-line treatment in West countries. Transjugular intrahepatic portosystemic stent-shunt (TIPS) and Warren stent procedure are primarily indicated in patients with variceal bleeding who fail to respond to pharmacological and endoscopic management. The splenectomy plus devascularization are commonly abandoned. Liver transplantation is candidated for patients with advanced liver cirrhosis. Under the circumstances, it is warranted to search for a more effective and safer minimally invasive alternative for hypersplenism. Radiofrequency ablation (RFA) is a representative technique of interstitial thermal ablation, with advantages of minimal invasion, safety and simple to deploy. RFA uses the energy of 450-500KHz radiowaves for thermal ablation of tumors, a flux of high-frequency alternating current passes through the needle tip into the surrounding tissue, generating rapid vibration of the ions in the tissue and frictional heat, the heat is subsequently conducted into the surrounding tissue, causing coagulative necrosis at a temperature between 50oC and 100oC.Objective This study attempted to treat hypersplenism with RFA technique, as a new minimally invasive procedure, with using RFA in animals and patients with cirrhotic hypersplenism, to investigate the feasibility and effectiveness of RFA in treatment of hypersplenism due to portal hypertension, and to provide scientific data and clinical evidence for future clinical performance.Methods and Results 1. A canine model of secondary hypersplenism was established by ligation of splenic vein and its collateral branches, and RFA was performed in spleen, subsequently the radiologic and pathologic characteristics of RFA lesions, procedure-related complications and the outcomes were examined. The results showed that stable thrombocytopenia, erythropenia and splenomegaly were presented in the dogs with splenic vein ligation, and the spleen was eligible for deploying RFA. thrombocytopenia, erythropenia were ameliorated by splenic RFA, and no major complications and mortality was occurred. The RFA procedure in spleen also caused unique radiologic and pathologic changes, such as "bystander effect" of necrotic zone and infarcted zone destroying splenic tissue with maximum diameter of 7-10cm, and poorly-vascularized changes and interstitial fibrosis of spleen that named "consolidated transformation of remnant spleen". 2. Canine model of hepatic fibrosis was induced by feeding carbon tetrachloride (CCl4) in peanut oil (1:1) to dogs through oral-gastric tube with 0.4-0.5ml/kg weight twice a week over 10 weeks. On the eleven week, animals were treated with RFA, and the hemodynamics of portal vein and splenic vein were monitored with color Doppler flow imaging (CDFI). The results revealed that hepatci fibrosis and portal hypertension were successfully established in all animals, and RFA procedure was enough safe for this portal hypertension model even without occlusion of splenic blood flow. The portal vein pressure, flows of portal vein and splenic vein were decreased by RFA. However, larger ablated lesions and significant lowering of splenic vein flow were obtained by RFA therapy with occlusion of splenic blood flow. 3. Radiofrequency ablation was practiced clinically for patients with hypersplenism due to cirrhotic...
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