Abstract: An assembly for delivering optical signals comprising a nuclear magnetic resonance system; an optical interface assembly electrically connected to the nuclear magnetic resonance system, the optical interface assembly comprising a first laser for producing laser optical signals, an interface optical to electrical signal convertor, and an interface optical connector assembly; and a catheter assembly comprising a proximal end, a distal end, and a catheter optical connector assembly disposed at the proximal end and connected to the interface optical connector assembly of the optical interface assembly, a fiber optic cable assembly, an electronics assembly disposed at the distal end comprised of a catheter electrical to optical signal convertor and a catheter optical to electrical signal convertor, and a first receiving coil disposed at the distal end.