Subjective visual vertical after treatment of benign paroxysmal positional vertigo

Abstract Introduction: Otolith function can be studied by testing the subjective visual vertical, because the tilt of the vertical line beyond the normal range is a sign of vestibular dysfunction. Benign paroxysmal positional vertigo is a disorder of one or more labyrinthine semicircular canals caused by fractions of otoliths derived from the utricular macula. Objective: To compare the subjective visual vertical with the bucket test before and immediately after the particle repositioning maneuver in patients with benign paroxysmal positional vertigo. Methods: We evaluated 20 patients. The estimated position where a fluorescent line within a bucket reached the vertical position was measured before and immediately after the particle repositioning maneuver. Data were tabulated and statistically analyzed. Results: Before repositioning maneuver, 9 patients (45.0%) had absolute values of the subjective visual vertical above the reference standard and 2 (10.0%) after the maneuver; the mean of the absolute values of the vertical deviation was significantly lower after the intervention (p &lt; 0.001). Conclusion: There is a reduction of the deviations of the subjective visual vertical, evaluated by the bucket test, immediately after the particle repositioning maneuver in patients with benign paroxysmal positional vertigo.摘要与引言：可通过检测主观视觉垂直（subjective visual vertical）来评估耳石功能，因为垂直线倾斜超出正常范围是前庭功能障碍的指征。良性阵发性位置性眩晕（benign paroxysmal positional vertigo）是由椭圆囊斑来源的耳石碎片脱落，累及一条或多条迷路半规管所致的疾病。 研究目的：对比良性阵发性位置性眩晕患者在粒子复位术（particle repositioning maneuver）前后及术后即刻的主观视觉垂直与桶试验（bucket test）结果。 研究方法：纳入20例患者进行评估。在粒子复位术前后及术后即刻，测量桶内荧光线达到垂直位置时的估计位置；对数据进行制表并开展统计学分析。 研究结果：粒子复位术前，9例患者（45.0%）的主观视觉垂直绝对值超出参考标准范围，术后即刻仅2例（10.0%）；干预后垂直偏差绝对值的均值显著降低（P<0.001）。 研究结论：良性阵发性位置性眩晕患者接受粒子复位术后即刻，通过桶试验评估的主观视觉垂直偏差程度有所降低。