Table 1.
Clinical and neurophysiological profiles in 140 ALS patients.
Fig 1.
Nerve excitability indices in healthy control and ALS.
Averaged excitability indices in normal controls (NC) (n = 44) and total amyotrophic lateral sclerosis (ALS) cohort (n = 142). Compared to NC, significant greater strength-duration time constant (SDTC) (*p < 0.05) (A), greater depolarizing threshold electrotonus (TEd) (TEd 10-30ms and TEd 90-100ms; *p < 0.05) (B), increased superexcitabilty (*p < 0.05) and reduced late subexcitability (*p < 0.05) in recovery cycle (C) and increased 40% depolarizing currents in current threshold relationship (I/V) (*p < 0.05) (D) were found in amyotrophic lateral sclerosis (ALS) patients. Data are given as mean ± SE.
Fig 2.
Scatter plots of nerve excitability indices and CMAP amplitudes.
Scatter plots of nerve excitability indices and compound muscle action potential (CMAP) amplitudes in 140 ALS patients. These indices were recorded over the abductor pollicis brevis (APB) muscle, stimulated in the median nerve at the wrist. SDTC (A) (p = 0.01, r = -0.22), superexcitability (B) (p = 0.45, r = 0.067) and TEd 90-100ms (C) (p = 0.01, r = -0.22) were increased with CMAP decline. Approximate lines are shown in each index. These findings suggest increased persistent sodium and decreased potassium currents deteriorate with axonal loss. Open circles represent normal average ± 1.96SE value in each index.
Table 2.
The correlation between nerve excitability indice and CMAP amplitude.