An exemplary method includes emitting radiation subcutaneously； sensing at least some of the emitted radiation as reflected cutaneously； detecting an abnormal physiologic condition； and, based at least in part on the sensing, adjusting a stimulation therapy to treat the detected abnormal condition. In such a method, the abnormal condition may be an abnormal cardiac condition, an abnormal neural condition or other condition. Various other methods, devices, systems, etc., are also disclosed.
