T2*-weighted magnetic resonance imaging used to detect coagulative necrosis in tissue

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item.Includes bibliographical references.Issued also on microfiche from Lange Micrographics.As the use of hyperthermic medical procedures increases, it has become more important to be able to non-invasively monitor the volume of treated tissue in real-time (or near real-time), not only to ensure that diseased tissue is destroyed, but also to prevent unnecessary collateral damage to surrounding healthy tissue. This research focuses on using T2*-weighted FLASH magnetic resonance imaging to detect irreversible changes in i . n vitro bovine liver tissue and tissuesimulating polyacrylamide gel phantoms following heating from physiologic levels into temperature regions used to induce coagulative necrosis. All samples were heated from physiologic levels to hyperthermic levels at specific intervals and imaged using a closed-loop water bath. Signal intensities were calculated and a comparison was made between images acquired at baseline temperatures and those images taken while at increased temperature. Results indicate that signal intensity levels do not return to baseline values in the samples following heating to levels known to result in coagulation, and for those samples which were heated to lower temperatures, these effects were not seen. The effects on image intensity may possibly provide a method to predict the coagulation front during hyperthermic procedures