A microsurgical tool is configured for monitoring, evaluating, mapping, and/or modulating electrophysiological activity in the vicinity of a lumen within a body. The microsurgical tool may be part of a system used in evaluating the sympathetic tone of a subject and/or neuromodulating an anatomical site in the vicinity of a lumen within a body. Such systems include a catheter system for controlled sympathectomy procedures and/or controlled micro ablation procedures. Such systems may be used in methods for performing a controlled surgical procedure, including performing controlled surgical procedures in a minimally invasive manner.