a. Dosing of Contrast - procedure performed exclusively for research purposes i. While the patient is still sedated and before tissue sampling, the experimental aspect of the procedure will begin. At this time, they will receive a dose of Definity intravenously through their peripheral IV access after being agitated. The dose of Definity will be 10 microliters/kg given in one to two doses, and will not exceed 2cc. A saline flush will follow the injection of the contrast and a timer will be started. The remaining contrast will be properly disposed of in a sharps container.