Table 1.
Seizure susceptibility in the PTZ test on day (D) 30, D60, D90, and D180 after lateral-fluid-percussion-induced traumatic brain injury (TBI) or sham operation.
| Parameter (General linear model) |
Group | Time of PTZ Test | Intragroup Statistics (Friedman’s 2-way ANOVA) |
|||
|---|---|---|---|---|---|---|
| D30 | D60 | D90 | D180 | |||
| Latency to 1st spike | Sham (16) | 220 ± 215 (16) |
191 ± 340 (16) | 278 ± 447 (16) |
149 ± 141 (16) |
Friedman’s 2-way ANOVA p = 0.036
Bonferroni corrected p > 0.05 (all) |
| TBI (28) |
280 ± 432 (27) |
204 ± 296 (28) | 140 ± 85 (28) (Cohen’s d 0.50) |
173 ± 179 (27) |
NS | |
| Latency to 1st ED |
Sham (16) | 316 ± 388 (16) |
205 ± 341 (16) | 359 ± 546 (16) |
239 ± 230 (16) |
Friedman’s 2-way ANOVA p = 0.026
D60–D90 Bonferroni-corrected p = 0.024 |
| TBI (28) |
480 ± 662 (27) |
311 ± 422 (28) | 176 ± 138 (28) (Cohen’s d 0.53) |
227 ± 180 (27) |
Friedman’s 2-way ANOVA p = 0.015
D30–D90 Bonferroni-corrected p = 0.011 |
|
| Latency to 1st seizure | Sham (16) | 1192 ± 1374 (5) |
197 ± 84 (5) |
658 ± 1168 (7) |
588 ± 853 (9) |
NS |
| TBI (28) |
370 ± 209 (4) (Cohen’s d 0.79) |
276 ± 148 (12) | 177 ± 93 (15) (Cohen’s d 0.75) |
326 ± 287 (16) |
Friedman’s 2-way ANOVA p = 0.044
D30–D90 Bonferroni-corrected p = 0.037 |
|
| Number of spikes |
Sham (16) | 1342 ± 1127 (16) |
1720 ± 1187 (16) | 1260 ± 1743 (16) |
1598 ± 1362 (16) | NS |
| TBI (28) |
1329 ± 812 (27) |
1447 ± 1030 (28) | 1600 ± 1404 (28) |
1467 ± 1363 (27) | NS | |
| Number of EDs | Sham (16) | 157 ± 137 (16) |
163 ±105 (16) | 161 ± 112 (16) |
139 ± 97 (16) |
NS |
| TBI (28) |
176 ± 124 (27) |
170 ± 132 (28) | 175 ± 138 (28) |
119 ± 98 (27) |
NS | |
| Number of seizures (Time effect 0.000) |
Sham (16) | 0.31 ± 0.48 (16) |
0.38 ± 0.62 (16) | 0.44 ± 0.51 (16) |
1.06 ± 1.12 (16) |
Friedman’s 2-way ANOVA p = 0.041
Bonferroni-corrected p > 0.05 (all) |
| TBI (28) |
0.19 ± 0.48 (27) |
0.82 ± 1.22 (28) | 0.82 ± 0.91 (28) |
1.15 ± 1.10 (27) |
Friedman’s 2-way ANOVA p = 0.000
D30–D180 Bonferroni-corrected p = 0.006 |
|
| Duration of 1st seizure | Sham (16) | 30 ± 7 (3) |
58 ± 22 (5) |
76 ± 43 (7) |
53 ± 36 (9) |
NS |
| TBI (28) |
64 ± 70 (4) (Cohen’s d 0.62) |
64 ± 33 (12) |
69 ± 32 (15) |
76 ± 22 (16) (Cohen’s d 0.82) |
NS | |
Data are shown as the mean ± standard deviation of the mean. Animal numbers are shown in parentheses. Abbreviations: D, day; ED, epileptiform discharge; NS, not significant; PTZ, pentylenetetrazol; TBI, traumatic brain injury. Statistical significance: time, group, and time x group effects were tested using a general linear model (left column in parentheses). Differences between timepoints within the sham or TBI groups were tested using related-samples Friedman’s 2-way ANOVA with Bonferroni correction for multiple testing (right column). No differences were detected between the sham and TBI groups at any testing point (Mann–Whitney U test). However, Cohen’s delta between the sham and TBI group, showed moderate (≥0.50) and large effect sizes (≥0.80) (in parentheses).