The Mayo laboratory utilizes two test batteries, the autonomic reflex screen (ARS) and the reflex sympathetic dystrophy (RSD) screen. The former comprises the quantitative sudomotor axon reflex test (QSART), orthostatic blood pressure (BP) and heart rate (HR) responses to tilt, HR response to deep breathing, the Valsalva ratio, and beat-to-beat BP responses to the Valsalva maneuver, tilt, and deep breathing. The RSD screen comprises the recording of... skin temperature, resting sweat output, and QSART distributions bilaterally.
Quantitative Sensory Testing (QST) is a valuable method for diagnosing peripheral nervous system disorders, including chronic pain and pain related to various diseases, such as Diabetes and CRPS. QST essentially determines the sensation and pain thresholds for cold and warm temperatures, and the vibration sensation threshold by stimulating the skin and comparing the results to normative values built in the software. When the stimulus activates stimuli-specific receptors; the nerve fibers that innervate the receptors communicate the stimuli's message to the central nervous system, where feeling occurs.
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