An assembly for delivering optical signals comprising a nuclear magnetic resonance system comprised of magnets, an NMR programmable logic unit, a signal input channel, and a command output channel; an optical interface assembly electrically connected to the nuclear magnetic resonance system, the optical interface assembly comprising a first laser modulated so as to produce laser optical signals, an interface optical to electrical signal convertor; and a catheter assembly connected to said optical interface assembly, the catheter assembly comprising a proximal end, a distal end, 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.