2004 Grant Recipient

“Evaluation of Cerebral Microemboli during Radiofrequency Ablation of Lung Tumors in a Canine Model ”

Kamran Ahrar, MD MD Anderson Cancer Center Radiofrequency ablation (RFA) has been approved by the United States Food and Drug Administration for causing coagulation necrosis of soft tissue tumors. This technique is widely used for treating hepatic tumors, and there has been recent interest in exploring nonhepatic applications of RFA.

However, some concern exists about potential adverse effects of RFA related to the nature of its mechanism of action. During RFA of hepatic tumors, sonography often detects temporary changes in echogenicity that occur in the area being treated. These changes are believed to result from the formation of gas microbubbles. During RFA of lung tumors, these microbubbles may diffuse into the pulmonary veins and embolize to the cerebral circulation where they may cause ischemia. The overall goal of Dr. Ahrar's project is to evaluate the frequency and timing of the occurrence of these cerebral microemboli during RFA of lung tumors and to investigate the potential adverse effects of these microemboli, including ischemic changes, on the brain parenchyma by means of diffusion-weighted MRI.