Abstract:Objective To explore the correlation between semicircular canal dysfunction and residual dizziness after otolith repositioning for benign paroxysmal positional vertigo (BPPV), and to analyze the etiology and related influencing factors of residual dizziness from the perspective of semicircular canal dysfunction, providing a clinical basis for the development of vestibular rehabilitation programs based on semicircular canal function recovery for the treatment of BPPV and residual dizziness after otolith repositioning. Methods A total of 80 patients with BPPV who met the inclusion criteria and were admitted to the Department of Neurology of Guilin Hospital of Traditional Chinese Medicine from 2024 to 2025 were selected. All patients received repositioning treatment for otolithiasis. According to the presence or absence of residual dizziness after repositioning, they were divided into the observation group (BPPV repositioning with residual dizziness, n=42) and the control group (BPPV repositioning without residual dizziness, n=38). Both groups underwent comprehensive semicircular canal function tests, including rotational tests (sine harmonic acceleration test and velocity step test), video head impulse test (vHIT), and caloric test, and etiological assessment was conducted for the patients. Results In the posterior semicircular canal BPPV and horizontal semicircular canal BPPV subgroups, there were statistically significant differences in the caloric test-related indicators between patients with residual dizziness and those without (P<0.05), including bilateral horizontal semicircular canal ultra-low-frequency function, temperature-induced nystagmus, left cold air response, and right cold air response. In the posterior semicircular canal BPPV residual dizziness group, there were significant differences in the abnormal rate of vHIT, positive rate of compensatory saccades in the left horizontal semicircular canal, and asymmetry ratio of horizontal head impulse gain between groups (P<0.05). In the horizontal semicircular canal BPPV residual dizziness group, there were statistically significant differences in the abnormal rate of vHIT, positive rate of compensatory saccades in the left and right horizontal semicircular canals, and asymmetry ratio of horizontal head impulse gain (P<0.05). In the posterior semicircular canal BPPV residual dizziness group, there were significant differences in the abnormal rate of rotational tests and unilateral attenuation values between groups (P<0.05). The comparison of the rotation test results between the two groups of residual dizziness patients with horizontal semicircular canal BPPV also showed significant differences in the abnormal rate, unilateral attenuation value, and slow phase velocity (P<0.05). The mean Hospital Anxiety and Depression Scale score of the observation group was 17.48 points, while that of the control group was 9.68 points, with a significant difference between the two groups. Conclusions The combined application of cold and heat test, rotation test and vHIT detection reveals that patients with residual dizziness after BPPV repositioning have varying degrees of semicircular canal dysfunction, and many are accompanied by a certain degree of anxiety and depression. The combined assessment of semicircular canal function by these three tests has important clinical value.
