An optical coherence tomography (OCT) catheter, for performing high performance elastographic deformation mapping of tissues and plaques, comprises: a catheter having elongated catheter body extending longitudinally between a proximal end and a distal end along a longitudinal axis, the catheter body including a distal portion at the distal end and a catheter lumen a palpator, disposed in the distal portion, to apply one of a directed fluid or a mechanical indenter to produce a surface-applied palpation force to a target area of the interior body to mechanically displace the interior body and cause elastographic deformation of the target area of one or more surface and subsurface tissues and plaques and OCT imaging sensor, disposed in the distal portion, to direct and deliver OCT beam for OCT deformation detection including elastographic deformation measurement to provide elastographic mapping of the target area.