[Subjective visual horizontal in peripheral unilateral vestibular dysfunction].

Objective: To analyze the characteristics of subjective visual horizontal (SVH) and evaluate its clinical value for vestibular function in peripheral unilateral vestibular hypofunction (UVH).

Methods: Eighty-five patients with UVH (study group) and 39 normal persons (control group) accepted vestibular function tests, including SVH, subjective visual vertical (SVV) and caloric test by video-nystagmography. The parameters of the angle of SVH and SVV, directional preponderance (DP) and unilateral weakness (UW) of caloric test were observed. The correlation between SVH/SVV, DP, UW and the course of disease were investigated respectively. SPSS 16.0 software was used to analyze the data.

Results: Reference range of SVH and SVV was from -2° to 2° in the control group. Among the 85 patients, 46 cases (54.1%) and 43 cases (50.6%) had the abnormal values of SVH and SVV respectively, with no statistical significance (χ(2) = 12.5, P = 0.481) by chi square test. Fifty-five cases (64.7%) with abnormal DP had no statistical significance when compared with SVH and SVV respectively (χ(2) values were 0.19 and 2.86, respectively, P value were 0.164, 0.067, respectively). In UVH, there were positive correlation between SVH, SVV and DP (r value was 0.939, 0.648, 0.658, all P < 0.05) respectively, but no correlation between UW and SVH or SVV (r value was 0.048, 0.085, all P > 0.05). According to the permutation and combination of the four parameters, positive or negative, three main groups could be defined [SVH(+)DP(+)UW(+), SVH(-)DP(+)UW(+), SVH(-)DP(-)UW(+); SVV(+)DP(+)UW(+), SVV(-)DP(+)UW(+), SVV(-)DP(-)UW(+)]. The course of disease in the three main groups was positively skewed distribution, with median of 5.0, 10.0, 15.0 d and 5.0, 9.5, 14.5 d respectively. By Kruskal-Wallis Test, χ(2) value were 8.80 and 6.26, respectively(P value were 0.012, 0.040, respectively), with statistical significance between the above three main groups.

Conclusions: The SVH value can evaluate the function of the otolithic. The angle of SVH and SVV are changing in the course of disease, SVH and SVV can be used as a guidance of the vestibular compensation evaluation.