Table 2.
VOR gain of quantitative HIT in patients with PICA stroke and VN.
| Gain, mean ± 2SD | PICA (n = 17) | VN (n = 17) | HS (n = 17) | p-value (PICA vs. VN) | p-value (PICA vs. HS) | ||||
|---|---|---|---|---|---|---|---|---|---|
| (95% CI) | i | c | i | c | i | c | i | c | |
| HC | 0.87 ± 0.13 (0.80–0.93) | 0.84 ± 0.13 (0.77–0.90) |
0.52 ± 0.16 (0.44–0.61) | 0.91 ± 0.04 (0.88–0.93) |
0.96 ± 0.02 (0.95–0.97) | <0.001a | 0.045a | 0.007a | <0.001a |
| PC | 0.89 ± 0.13 (0.82–0.96) | 0.87 ± 0.15 (0.80–0.95) |
0.87 ± 0.09 (0.82–0.92) | 0.92 ± 0.05 (0.89–0.95) |
0.99 ± 0.04 (0.98–1.00) | 1.00b | 0.97b | <0.001a | <0.001b |
| AC | 1.00 ± 0.99 (0.95–1.04) | 0.98 ± 0.09 (0.94–1.03) |
0.60 ± 0.06 (0.57–0.64) | 0.93 ± 0.08 (0.88–0.97) |
0.98 ± 0.03 (0.97–0.99) | <0.001b | 0.049b | 0.098b | 0.268a |
| Abnormal gain, n (%)e | |||||||||
| HC | 9 (52.9%) | 12 (70.6%) | 17 (100%) | 4 (23.5%) | 2 (5.9%) | 0.003c | 0.004c | <0.001c | <0.001c |
| PC | 8 (48.1%) | 10 (58.8%) | 8 (47.1%) | 10 (58.8%) | 2 (5.9%) | 0.98c | 0.95c | <0.001c | <0.001c |
| AC | 3 (17.6%) | 2 (11.7%) | 12 (70.6%) | 7 (41.2%) | 0 (0%) | 0.02c | 0.11c | 0.033c | 0.107c |
| Gsd (95% CI) | |||||||||
| HC | 0.08 ± 0.08 (0.04–0.12) | 0.38 ± 0.17 (0.29–0.48) | 0.02 ± 0.02 (0.01–0.03) | <0.001b | 0.002b | ||||
| PC | 0.06 ± 0.05 (0.03–0.09) | 0.07 ± 0.06 (0.03–0.10) | 0.03 ± 0.04 (0.01–0.05) | 0.71b | 0.045b | ||||
| AC | 0.05 ± 0.06 (0.02–0.08) | 0.33 ± 0.04 (0.29–0.36) | 0.04 ± 0.03 (0.02–0.05) | <0.001b | 0.929b | ||||
| Abnormal gain asymmetry, n (%)e | |||||||||
| HC | 9 (52.9%) | 17 (100%) | 1 (5.9%) | 0.003c | 0.003c | ||||
| PC | 4 (23.5%) | 3 (20.0%) | 1 (5.9%) | 0.81c | 0.335c | ||||
| AC | 2 (11.8%) | 5 (33.3%) | 1 (5.9%) | 0.21c | 1.000c | ||||
PICA, posterior inferior cerebellar artery; VN, vestibular neuritis; HS, healthy subjects; SD, standard deviation; CI, confidence interval; HC, horizontal canal; PC, posterior canal; AC, anterior canal; Gs, gain asymmetry; i, ipsilesional; c, contralesional.
a
Independent t-test;
b
Mann–Whitney U test;
c
Fisher's exact test;
d
gain asymmetry was defined as the absolute difference between ipsilesional and contralesional gains;
e
abnormal gain and abnormal gain asymmetry were defined as −2 SDs below the mean and as above mean +2 SDs of 95% of normal subjects incorporated, respectively. The value in parentheses below the mean ± SD represents the 95% CI.