Analysis of the dysfunction frequency and characteristics of semicircular canal in benign paroxysmal positional vertigo / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To assess the characteristics of the dysfunction of semicircular canal in benign paroxysmal positional vertigo and the relationship with the ectopic otoconia.</p><p><b>METHODS</b>There were 214 patients with benign paroxysmal positional vertigo (BPPV), including 107 cases of posterior semicircular canal canalithiasis (PSC-Can) 80 cases of horizontal semicircular canal canalithiasis (HSC-Can), 27 cases of horizontal semicircular canal cupulolithiasis (HSC-Cup). One hundred and ninety (88.8%) patients were accompany with relevant diseases while 24 (11.2%) cases were not. They accepted low, middle and high frequency vestibular function tests, including caloric test (CT), head shaking test (HST) and video head impulse test (vHIT) respectively. The parameters of the unilateral weakness (UW), head shaking nystagmus (HSN) and video head impulse test gain (vHIT-G) were observed. Patients classified into three groups (PSC-Can, HSC-Can, HSC-Cup) according to the involvement semicircular canal. The results of the three tests were analyzed with SPSS16.0 software.</p><p><b>RESULTS</b>The positive cases of the three tests were vHIT: 15 (7.0%), HST: 52 (24.3%), CT: 152 (71.0%), a statistically significant difference (P < 0.05) was found between the three tests. When compared the Caloric Test, HST and vHIT between the BPPV patients with and without relevant diseases, there were no significant differences (P > 0.05). The variance without statistical significance (P > 0.05) was showed between three tests' results in each groups, it was also showed that the variance between the three groups in each tests reached no statistical significance (P > 0.05). The test of affected side UW between PSC-Can, HSC-Can and HSC-Cup showed the variance without statistical significance (F = 0.970, P = 0.383).</p><p><b>CONCLUSIONS</b>The lesion of semicircular canals has the same etiological factors with the utricle pathological change in benign paroxysmal positional vertigo, and the dysfunction mostly happens in low frequency range of semicircular canal frequency band. The ectopic otoconia is not the main etiological factors for that. HST and vHIT of middle and high frequency can not be ultimately used for the screening test evaluating due to the semicircular canal function in BPPV.</p>

Analysis of directional preponderance of caloric test in evaluation of vestibular dynamic compensation / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To analyze the value of directional preponderance (DP) in vestibular dynamic compensation evaluation.</p><p><b>METHODS</b>One hundred fifty-five patients with sudden deafness accompanied vertigo were asked to accept routine vestibular tests including the spontaneous nystagmus (SN) and caloric test with video-nystagmography. DP, SN and unilateral weakness (UW) were selected as the observation parameters. Then the correlation analysis between DP, SN, UW and course of disease were investigated respectively. The change characteristic of the three parameters was also analyzed in the course of vestibular compensation.</p><p><b>RESULTS</b>Of the 155 patients, there were negative correlations between SN, DP and course of disease (r(s) = -0.386, r(s) = -0.424, P < 0.05), positive correlation between SN and DP (r(s) = 0.543, P < 0.05), but no correlation between UW and course of disease (r(s) = 0.004, P > 0.05), and also positive correlation (r(s) = 0.274, P < 0.05) between DP and UW. According to three parameters were positive or negative, three main groups (DP+UW+SN+, DP+UW+SN- and DP-UW+SN-) in DP, UW, SN. The course of disease in three main groups was positively skewed distribution. Median was 6 days, 10 days and 20 days respectively. Through Kruskal-Wallis Test, chi(2) = 24.63, P < 0.05, there was statistical significance among the above three main groups.</p><p><b>CONCLUSIONS</b>DP keeps on changing in the acute stage, static and dynamic compensation stage of peripheral vestibular disease. This indicates that DP can be considered as an objective evaluation index of vestibular dynamic compensation and as a guidance of the vestibular rehabilitation evaluation.</p>