Table 4.
Latencies and Amplitudes of SEP Components—Pre–Posttest –Studies made on stroke population.
| Study/sample size | SEP components (latencies and amplitudes) | Test time/follow-up and statistical analysis | Significant effects | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Bao et al. (12) 90 stroke patients |
Not provided | Baseline, end of week 8 Paired t-tests and McNemar tests, 1-way ANOVA, χ2 tests |
Significant differences in latency and peak value of SEP between the two groups at the end of the eighth week (p < 0.05), but not at baseline (p > 0.05). | ||||||
| Latency (ms) | Peak (μV) | ||||||||
| Baseline | 8 weeks | P value | Baseline | 8 weeks | P value | ||||
| Group A | 43.7 ± 5.56 | 38 ± 3.6 | P < 0.05 | 1.44 ± 0.52 | 2.13 ± 0.51 | P < 0.05 | |||
| Group B | 44.1 ± 6.97 | 27.3 ± 5.36 | P < 0.01 | 1.53 ± 0.46 | 2.94 ± 0.59 | P < 0.01 | |||
| P-value | 0.89 | P < 0.01 | 0.7 | P < 0.01 | |||||
| Peurala et al. (13) 59 stroke patients |
The SEP of MN at the wrist: N20, N30, N60, (patients with hand stimulation treatment) and TN SEPs at the ankle: P40, N80, (patients with foot stimulation treatment) | Baseline, end of week 3 Paired samples t-test, nonparametric Wilcoxon and marginal homogenity test |
SEP normality classification improved significantly in paretic UL (p < 0.01) and in paretic LL (p < 0.05) in the stimulated group (n = 51) after 3 weeks of rehabilitation. | ||||||
| Hand SEP*(n = 8) | Before | After | Foot SEP*(n = 19) | Before | After | ||||
| 1 | 0 | 0 | 1 | 0 | 2 | ||||
| 2 | 3 | 3 | 2 | 10 | 10 | ||||
| 3 | 5 | 5 | 3 | 9 | 7 | ||||
| *SEP: 1, normal; 2, minor change; 3, abnormal | |||||||||
| Giaquinto, et al. (42) 102 stroke patients |
The UL SEP N20 latency, affected and unaffected side | Baseline, end of week 8 Mann–Whitney U-test, Student's t-test, Spearman correlation |
The mean amplitude N20 on the affected side increased compared to the baseline. Latencies did not change. | ||||||
| N20: Mean Amplitude SD | N20: Mean Latencies and SD | ||||||||
| Unaffected Hemisphere | Affected Hemisphere | Unaffected Hemisphere | Affected Hemisphere | ||||||
| Before | −3.4 μV (1.5) | −1.8 μV (1.4) df = 18, t = 3.716, P = 0.002 | 20.5ms (1.5) | 17.7ms (7.9) df = 18, t = 1.489, ns | |||||
| After (1.3) | −3.4 μV | −2.6 μV (1.2) df = 16, t =−2.270, P = 0.003 | 20.1ms (1.2) | 19.2ms (5.1) df = 16, t = 0.735, ns | |||||
| Before and after comparison | df = 016, t = 0.363, ns df = 16, t = 4.932, P = 0.0001 | ||||||||
| Tashiro et al. (15) 23 stroke patients |
NI(N20), PI(P25), NII(N33), PII(P45), NIII(N60) of the MN at the wrist and N31, P35, N42, P53, N66 of the TN at the ankle | Baseline, end of week 3; Wilcoxon signed-rank tests Student's t-test |
The Wilcoxon signed-rank test indicated that the number of cortical peaks significantly increased in the MN, but not in the TN in the non-paretic side (MN, p = 0.008; TN, p = 0.11), No significant changes in the MN between peak latencies of central SEP peaks and N18. Remarkable differences were detected in shortening of the latency between NI(N20)– PII(P45) after the intervention. | ||||||
MN, Median nerve; TENS, UL, Upper limb; HF-RSS, High Frequency Repetitive Somatosensory Stimulation; LL, Lower limb; TN, Tibial nerve.