Abstract: A wearable probe includes a sensor module and a control module. The sensor module includes a transmission source to transmit signals into the tissue at a source position, and two detectors to detect a result of the signals, the two detectors including a first detector positioned at a first separation distance from the source position and a second detector positioned at a second separation distance from the source position. The control module includes a controller and a battery to power the controller and the sensor module. The control module includes a processor, a memory including instructions, and a communications interface. The instructions cause the processor to control the sensor module to transmit signals into the tissue and detect results of the signals with the at least two detectors, receive the detected results, store the detected results in the memory, and transmit the detected results to a remote device.