Fig. 4.

DOT-MRI imaging sequence flow chart. The DOT-MRI instrument performs the optical and MRI measurements simultaneously. Structural T1- and T2-weighted MRI measurements are made prior to the injection of a gadolinium contrast agent. After the contrast injection, another set of MR images are acquired, thereby permitting subtraction imaging that enables optimal tumor contrast. Simultaneously, optical data are acquired. First, TD measurements are made at several positions to determine absolute bulk optical properties. Then, CW measurements are made at all source and detector positions to enable full 3-D reconstruction.