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Table 1 Nerve conduction studies (NCS)

From: Isolated unilateral palatal and vocal cord palsy as an initial presentation of chronic inflammatory demyelinating polyradiculoneuropathy

NCS 02 September 2018NCS 16 September 2018
Motor nerve conduction study
NerveLatency (ms)Amplitude (mV)CV (m/s)Latency (ms)Amplitude (mV)CV (m/s)
 Left median
 Right median
 Left ulnar
  Below elbow8.95.5 NRNR 
 Right ulnar
  Below elbow9.63.9 10.40.5 
 Left peroneal
  Head of fibula14.25.3 14.80.5 
 Right peroneal
  Head of fibula16.21.7 NRNR 
 Left tibial
  Popliteal fossa16.66.9 17.4NR 
 Right tibial
  Popliteal fossa16.65.1 18.10.5 
F wavesLatency (ms)Latency (ms)
 Left median37.5  NR  
 Right medianNR  NR  
 Left ulnar33.3  46.4  
 Right ulnar33.5  NR  
 Left peroneal53.1  56.9  
 Right peroneal52.3  61.0  
 Left tibial59.0  66.6  
 Right tibial60.0  69.7  
Sensory nerve conduction study
 Sensory nervesPeak latencyAmplitude (mV)CVPeak latencyAmplitude (mV)CV
  Right medianNRNRNRNRNRNR
  Left median2.46.758.8NRNRNR
  Right ulnar3.85.832.6NRNRNR
  Left ulnar2.57.348.4NRNRNR
  Right sural2.36.053.9NRNRNR
  Left sural2.46.159.4NRNRNR
  1. NCS 1: The motor nerve conduction studies show normal distal latency with normal CMAP amplitude distally in both ulnar and tibial. There are prolonged latency in the left median and both peroneal nerves with reduced amplitudes distally with normal conduction velocities (CV). The right median nerve was in- elicitable. F wave latency is prolonged in left median nerve with rest being normal. Sensory nerve conductions show absent SNAP in right median with normal peak latency and conduction velocity in both ulnar and sural nerves
  2. NCS 2: The motor nerve conduction studies showed prolonged distal latencies in both ulnar, tibial and peroneal nerves with reduced amplitudes distally and conduction block with more than 50% reduction in amplitude on proximal stimulation in right ulnar nerve with reduced conduction velocities. F wave latencies are prolonged in bilateral tibial and peroneal nerves with absent F wave latency in the bilateral median and right ulnar nerves. Sensory nerve conductions being non-recordable in all tested nerves
  3. NCS nerve conduction studies, CV conduction velocity, NR not recordable