Feasibility and Sensitivity of TRUST Measurements in the Upper Arm

Motivation: T2-relaxation-under-spin-tagging(TRUST) is a non-invasive MRI technique to estimate blood oxygenation in the superior sagittal sinus from a T2 decay fit. Goal(s): The calibration curve to convert T2 into oxygenation has been derived with ex-vivo experiments for healthy volunteers and patients with specific types of sickle cell disease. Approach: Validation of these calibration curves is difficult because blood cannot be drawn from the superior sagittal sinus itself, hampering implementation of the technique in other patient groups. Results: Here, TRUST was adapted and optimized for the arm so that its measurements of venous oxygenation can be directly compared with venipunctures from the cephalic vein. Impact: The TRUST-sequence was optimized for non-invasive T2-measurement in the upper arm veins. A posteriori correlation with blood properties returns a venous oxygenation mapping. This may confirm the currently used calibration curve and facilitate obtaining accurate calibration curves for specific diseases.