Blood Oxygenation (BOX) Level Dependent Functional Brain Imaging using Steady-State Free Precession
Lee J, Gurney P, Nishimura D, Pauly J, Hargreaves B, Shankaranarayanan A, Miller K, Wright G, Dharmakumar R
Conventional BOLD imaging suffers from image distortion, signal dropout and low spatial and temporal resolution. The proposed method, which we refer to as BOX (Blood OXygenation), eliminates most of the problems by using SSFP acquisitions. Changes in the concentration of deoxyhemoglobin introduce frequency shifts and T2 relaxation time changes. Previous methods that incorporated SSFP for fMRI relied on the frequency shift to generate oxygen contrast. Such techniques suffer from the sensitivity to off-resonance. BOX exploits T2 changes to generate oxygen contrast over a broad range of off-resonance frequencies which results in distortion-free high spatio-temporal resolution 3D coverage.