A method and external control device for performing a medical procedure on a patient in which at least one stimulation lead is implanted. An electrical signal is conveyed from the stimulation lead into tissue of the patient. An electrical parameter indicative of tissue impedance is measured in response to the conveyance of the electrical signal. One of a plurality of different anatomical regions in which the stimulation lead is implanted is selected and/or a depth in which the stimulation is implanted is determined based on the measured electrical parameter. A stimulation parameter is defined based on the selected one anatomical region and/or implantation depth. Electrical stimulation energy from the stimulation lead is conveyed into the one determined anatomical region in accordance with the defined stimulation parameter.