[Analysis of clinical features of secondary benign paroxysmal positional vertigo].

Objective: To analyze the clinical features of secondary benign paroxysmal positional vertigo (BPPV) and provide evidence for its precise diagnosis and treatment. Method: There were 942 patients with vertigo related to BPPV, including 204 patients with primary BPPV, 592 patients with vestibular migraine (VM), 83 patients with Meniere's disease (MD), 48 patients with vestibular neuronitis (VN), and 15 patients with sudden sensorineural hearing loss (SSNHL) accompanied by vertigo.There were 127 patients with BPPV secondary to vertigo in MD, VN, VM, and SSNHL. All patients received otolith repositioning treatment by hand or instrument based on detailed medical history. Secondary BPPV patients are treated according to the principle of diagnosis and treatment of primary BPPV. The incidence of secondary BPPV in each related disease was counted, and the difference between primary and secondary BPPV in gender, age, affected semicircular canal, number of reductions, and vertigo control rate was compared. Result: ①The incidence of MD, VN, sudden vertigo, and VM secondary BPPV were 36.1% (30/83), 35.4%(17/48), 33.3% (5/15), and 12.7% (75/592). ②In patients with BPPV secondary to MD, the proportion of multi-semicircular canals involved was higher than that of primary BPPV, the difference was statistically significant ( P <0.05), and there was no significant difference in the distribution of semicircular canals involved among the remaining diseases. ③The vertigo control rate of BPPV secondary to MD and VM was lower than that of primary BPPV, and the difference was statistically significant ( P <0.05). ④The repositioning time of BPPV secondary to VM (2.88±2.32) and MD (2.53±1.14) was higher than that of primary BPPV (2.37±1.77). The difference was statistically significant ( P <0.05). There was no significant difference in the repositioning time between other secondary BPPV and primary BPPV. Conclusion: Common causes of secondary BPPV include MD, VN, SSNHL, and VM. Same as primary BPPV, the secondary BPPV was more common in women and the posterior semicircular canal was most affected. BPPV secondary to MD is more susceptible to multi-semicircular canals involvement than primary BPPV. Detailed medical history combined with targeted examination is conducive to the accurate diagnosis of BPPV. Secondary BPPV can also be treated by manipulation or instrument, however, the effect is worse than primary BPPV. Secondary BPPV should be treated according to the treatment principle of primary disease besides otolith repositioning.