Sensory testing examinations

It is important to be alert and well-rested when arriving for the examination, as it requires good concentration. 

Dress warmly for the examination, as the limbs must be at normal temperature for accurate measurements. If the back or lower limbs are to be examined, it is advisable to wear short-legged or legless underwear underneath, as long-legged clothing must be removed for the duration of the examination. 

In quantitative sensory testing (QST), thresholds for cold, warmth, cold pain, and heat pain sensations on the skin are determined. These sensations are transmitted to the central nervous system via thin sensory nerve fibers. QST is used to investigate peripheral nervous system diseases and injuries. The measurements reflect the entire sensory pathway from the skin to the cerebral cortex, so central nervous system-related nerve damage may also be detected through threshold changes. 

During the examination, a small thermistor plate is placed on the skin and either cooled or heated. The patient presses a button to indicate when the skin sensation changes. As the temperature continues to change, the patient indicates when the first pain sensation occurs. These temperatures are recorded as cold sensation, warm sensation, cold pain, and heat pain thresholds. Cold and warm sensation threshold measurements are repeated. 

Vibration sensory testing assesses the function of thick sensory nerve fibers. An actuator is placed on the skin surface, which vibrates. As the vibration intensity increases, the patient indicates when they first detect the vibration. This intensity is recorded as the vibration sensory. 

The examination does not require follow-up and does not impose any restrictions on normal daily activities. 

The physician who referred you for the examination will inform you of the results and how treatment will proceed. Contact your care unit if you do not have a scheduled appointment or call time. 

Sensory testing is completely safe.