1. WHAT IS NCS ? A nerve conduction study (NCS) : is a test used to evaluate/ detect the function of motor and sensory nerves of the human body. Nerve conduction velocity (NCV): is a common measurement made during this test.

2. The nerve conduction studies most commonly performed are compound muscle action potentials (CMAPs) for motor nerves, sensory nerve action potentials (SNAPs) for sensory nerves, compound nerve action potentials (CNAPs) for mixed (sensory and motor) nerves and late responses (primarily F- waves and H-reflexes). 3. Components : MNCS F WAVE RESPONSE SNCS H REFLEX REPETITIVE STIMULUS TEST-decrement EVOKED POTENTIALS SSEP VEP BAEP 4. NCS Latency Latency time interval between the Velocityonset of a stimulus and the onset of a amplitude response (can also be referred to as amotor latency or a sensory latency). Amplitude the maximal height ofthe action potential. Conduction velocity how fast thefastest part of the impulse travels (canalso be referred to as a motorconduction velocity or a sensoryconduction velocity). 5. NORMAL VALUES LATENCY AMPLITUDE VELOCITYULMOTOR N. < 4.0 ms5-10 mV 50-60m/sSENSORY N.