Yttrium-90 Radioembolization for Cirrhosis-Associated Thrombocytopenia

Inclusion Criteria: * Male or female, 18 years of age or older, of any ethnic or racial group. * Diagnosis of cirrhosis or portal hypertension with a serum platelet count less than or equal to 80 × 109/L. \[Rationale: platelet count \<100 × 109/L triples the rate of liver-related adverse events (3) and worsens postoperative survival in the setting of hepatocellular carcinoma (HCC) (4). Initial platelet count of 80 × 109/L can allow the majority of patients who successfully respond to 90Y-RE (clinical endpoint of 50% platelet count increase) to exceed the 100 × 109/L threshold.\] Cirrhosis is defined by one of three criteria: * Liver Biopsy/histology consistent with cirrhotic architectural liver changes * Portal hypertension (Hepatic venous pressure gradient ≥10 mm Hg) * Evidence of esophageal and/or gastric varices * Patients must have evidence of splenomegaly as determined by screening cross-sectional imaging. * No evidence of myelosuppression (e.g. lymphopenia) as evidenced by normal hematology values at Screening * Adequate baseline organ function(with the exception of cirrhosis) as evidenced by normal BUN/Cr and electrolytes on screening chemistry. * Eastern Cooperative Oncology Group (ECOG) Performance Status score of 0-2 * Patient has a life expectancy of greater than 6 months without intervention. * Patient is willing to participate in the study and has signed the study informed consent. * Women of childbearing potential must have a negative serum pregnancy test within 28 days prior to screening and must not be breastfeeding. Exclusion Criteria: * Patients with serum platelet count less than 10 × 109/L. * History of bleeding disorder attributed to another cause other than cirrhosis (e.g. Von Willebrand disease) * Declines or unable to provide informed consent * History of prior partial splenic embolization (PSE) or splenectomy * Use of any medication known to increase platelet count 1 month prior to Baseline. * History of allergy or sensitivity to TheraSphere® or its components. * History of severe peripheral allergy or intolerance to contrast agents, narcotics, sedatives or atropine that cannot be managed medically * Contraindications to angiography and selective visceral catheterization such as bleeding, diathesis or coagulopathy that is not correctable by usual therapy or hemostatic agents (e.g. closure device) * Previous randomization in a trial using 90Y RE * Patient must not have participated or enrolled in a clinical trial with an investigational device / therapy within 30 days prior to randomization * Any serious medical condition likely to impede successful completion of the study, such as certain mental disorders, cardiac arrhythmias, and uncontrolled congestive heart failure or respiratory disease. * Patients actively on chemotherapy.