An electrical stimulation lead assembly includes a lead body having a distal end portion, a proximal end portion, and a longitudinal length. Electrodes are disposed along the distal end portion of the lead body； terminals disposed along the proximal end portion of the lead body； and stimulation conductors couple the terminals to the electrodes. A cerebrospinal-fluid-pulsation detection assembly includes a sensor disposed along the distal end portion of the lead body. The sensor detects pulses of cerebrospinal fluid within a subarachnoid space of a patient and transforms the detected cerebrospinal-fluid pulses into sensor signals. A sensor processor receives the sensor signals from the sensor, processes the received sensor signals to cerebrospinal-fluid pulsation data (“CSF-pulsation data”), and estimates a patient blood-flow condition based on the CSF-pulsation data. A sensor control pathway couples the sensor to the sensor processor.
