Wu Jing, Zou Yihuai, Xu Wenyan, Ma Hongming, Huang Lixian, Zhao Bo, Sun Liman
Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China.
Front Neurol. 2024 Jul 10;15:1413929. doi: 10.3389/fneur.2024.1413929. eCollection 2024.
This study aimed to investigate the characteristics of positional nystagmus in patients with cupulolithiasis of the posterior semicircular canal-benign paroxysmal positional vertigo (PC-BPPV-cu) to improve clinical diagnostic accuracy.
This study retrospectively analyzed 128 cases of PC-BPPV-cu and 128 cases of canalolithiasis of BPPV (PC-BPPV-ca). General data, intensity, distribution, and the correlation of positional nystagmus were compared between the two groups.
Compared to the PC-BPPV-ca group, more cases from the PC-BPPV-cu group initially presented in the emergency department ( < 0.05). The most frequent positional nystagmus induced by PC-BPPV-cu was torsional-upbeat nystagmus, characterized by the upper pole of the affected eye beating toward the lower ear and vertically upward (387 cases, 59.7%). It was followed by torsional-downbeat nystagmus, characterized by the upper pole of the unaffected eye beating toward the lower ear and vertically downward (164 cases, 25.3%). The former represented posterior canal excitatory nystagmus (PC-EN), while the latter represented posterior canal inhibitory nystagmus (PC-IN). In the PC-BPPV-cu group, PC-EN was most easily caused by the Half Dix-Hallpike (HH) maneuver on the affected side, while PC-IN was most easily induced by a face-down position (FDP) on the unaffected side at approximately 45° angle (45° FDP). The vertical slow phase velocity (v-SPV) of positional nystagmus was more potent in the affected HH than in other positions with PC-EN (all < 0.05); the v-SPV of positional nystagmus was greater in the 45° FDP than in different positions with PC-IN (all < 0.05); the v-SPV of the affected Dix-Hallpike (DH) maneuver in the PC-BPPV-ca group was significantly greater than that of the affected HH maneuver in the PC-BPPV-cu group ( < 0.05). The analysis showed that the strongest correlation with HH positional nystagmus was observed in the affected side roll test, followed by the DH maneuver.
In the PC-BPPV-cu group, the HH maneuver most easily induced PC-EN on the affected side, and PC-IN was most easily induced by the 45° FDP. In some cases of PC-BPPV-cu, significant nystagmus was not observed to be induced in the DH position on the affected side; however, vertical rotation nystagmus was induced in the roll-test position on the affected side. In such cases, PC-BPPV-cu diagnosis should be considered, and HH and 45° FDP tests should be conducted to support the diagnosis.
本研究旨在探讨后半规管壶腹嵴耳石症 - 良性阵发性位置性眩晕（PC - BPPV - cu）患者的位置性眼震特征，以提高临床诊断准确性。
本研究回顾性分析了128例PC - BPPV - cu患者和128例嵴顶耳石症BPPV（PC - BPPV - ca）患者。比较两组患者的一般资料、眼震强度、分布及位置性眼震的相关性。
与PC - BPPV - ca组相比，PC - BPPV - cu组更多患者最初在急诊科就诊（<0.05）。PC - BPPV - cu诱发的最常见位置性眼震是扭转性上跳性眼震，其特征为患眼上极向下耳并垂直向上跳动（387例，59.7%）。其次是扭转性下跳性眼震，其特征为健眼上极向下耳并垂直向下跳动（164例，25.3%）。前者代表后半规管兴奋性眼震（PC - EN），后者代表后半规管抑制性眼震（PC - IN）。在PC - BPPV - cu组中，PC - EN最易由患侧的半Dix - Hallpike（HH）试验诱发，而PC - IN最易由患侧约45°角的俯卧位（45°FDP）诱发。位置性眼震的垂直慢相速度（v - SPV）在患侧HH试验中比其他PC - EN位置更强（均<0.05）；位置性眼震的v - SPV在45°FDP时比PC - IN的不同位置更大（均<0.05）；PC - BPPV - ca组患侧Dix - Hallpike（DH）试验的v - SPV显著大于PC - BPPV - cu组患侧HH试验的v - SPV（<0.05）。分析表明，与HH位置性眼震相关性最强的是患侧翻滚试验，其次是DH试验。
在PC - BPPV - cu组中，HH试验最易诱发患侧的PC - EN，45°FDP最易诱发PC - IN。在某些PC - BPPV - cu病例中，患侧DH位未观察到明显眼震诱发；然而，患侧翻滚试验位诱发了垂直旋转性眼震。在这种情况下，应考虑PC - BPPV - cu诊断，并进行HH试验和45°FDP试验以支持诊断。
