Method of imaging metabolic function

摘要

A contrast imaging method e.g. of the T2* weighted “BOLD” type is adapted by use together with an oxygen challenge to provide imaging for the assessment of the metabolic responses of tissue over a period of time the method utilizing three components, oxygen, deoxyhaemoglobin, and oxyhaemoglobin together with time, to provide four variable parameters which allows oxygen to be used as a metabolic marker that can be utilized in an imaging evaluation of soft tissue and organs, e.g. in the study of viable tissue and organ function or dysfunction, which allows utility in diagnosis and assessment of conditions such as cancer, dementia, circulatory disorders, and autoimmune disorders.

主权项

1. A method of identifying viable tissue in an ischemic target area of an organism using O2T2* dependent contrast magnetic resonance imaging (MRI), the method comprising the steps of:
i) intravenously administering an oxygen carrier to the organism; ii) calculating a baseline T2* imaging signal of the target area of the organism; iii) administering oxygen to said organism by oxygen inhalation and continuing the administration of oxygen until the increasing T2* imaging signal intensity reaches a peak; iv) generating imaging signal data of the target area during said administering, and calculating the peak T2* imaging signal of the target area, wherein the increasing T2* signal from the baseline imaging signal to the peak imaging signal indicates conversion of the deoxyhaemoglobin in the target area to oxyhaemoglobin; v) stopping the administration of oxygen by oxygen inhalation; vi) monitoring for return of the peak T2* imaging signal back to the baseline imaging signal wherein the administration of oxygen by inhalation remains stopped until the baseline imaging signal is recovered, and wherein the return of the peak T2* imaging signal back to the baseline imaging signal is indicative of deoxyhaemoglobin re-generation following extraction of oxygen from oxyhaemoglobin by the target area and thus oxygen turnover by the target area; and (vii) calculating the change in signal intensity between the peak T2* imaging signal and the baseline imaging signal of the target area; wherein, in response to oxygen inhalation, when there is: a) no increase in the T2* signal; b) no return of the peak T2* signal to the baseline imaging signal following cessation of oxygen administration; or c) a reduction in the T2* signal from the baseline imaging signal, non-viable ischemic tissue is indicated; and metabolically active tissue shows an increase in the T2* signal followed by a return of the T2* signal to baseline; and a viable ischemic tissue is identified as the tissue having the highest relative increase in T2* signal.