Department of Radiology.
Department of Otorhinolaryngology-Head and Neck Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Republic of Korea.
Otol Neurotol. 2019 Apr;40(4):e393-e398. doi: 10.1097/MAO.0000000000002104.
To demonstrate characteristic nystagmus findings in acute otitis media (AOM) complicated by serous labyrinthitis and discuss the mechanism of direction-changing positional nystagmus (DCPN) in this condition.
A patient with AOM complicated by serous labyrinthitis on the left side.
Video nystagmography and 3D fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI).
Characterize positional nystagmus in a head-roll test observing the change of nystagmus direction in process of time and compare findings of temporal bone 3D FLAIR MRI.
A previously healthy 50-year-old man who complained of acute otalgia, hearing loss, and vertigo was diagnosed with AOM complicated by serous labyrinthitis on the left side. A head-roll test performed on the day when vertigo developed showed persistent geotropic DCPN. While pre- and postcontrast T1-weighted MRI showed no signal abnormality in both inner ears, 10-minute delay postcontrast 3D FLAIR image showed enhancement in the inner ear on the left side. Four-hour-delay postcontrast 3D FLAIR images showed more conspicuous enhancement of the whole cochlea, vestibule, and semicircular canals on the left side.
In AOM complicated by serous labyrinthitis, density of perilymph may increase due to direct penetration of cytokines and other inflammatory mediators from the middle ear into perilymph and breakdown of blood-labyrinth barrier that causes vascular leakage of serum albumin into perilymph. The density difference between perilymph and endolymph makes the semicircular canal gravity sensitive. A buoyant force is also generated by gravity, causing indentation of endolymphatic membrane in the ampulla and cupula displacement. Thus, at the early stage of serous labyrinthitis, a head-roll test may elicit persistent geotropic DCPN, of which the direction can be changed over time.
展示急性中耳炎（AOM）并发浆液性迷路炎时特征性眼球震颤表现，并探讨该情况下变向位置性眼球震颤（DCPN）的发生机制。
左侧 AOM 并发浆液性迷路炎患者。
视频眼震图和三维液体衰减反转恢复（FLAIR）磁共振成像（MRI）。
在头倾试验中观察眼球震颤方向随时间的变化来描述位置性眼球震颤的特征，并比较颞骨三维 FLAIR MRI 的结果。
一位 50 岁健康男性，主诉急性耳痛、听力损失和眩晕，被诊断为左侧 AOM 并发浆液性迷路炎。眩晕发作当天进行的头倾试验显示持续向地性 DCPN。虽然双侧内耳的预增强和增强后 T1 加权 MRI 未见信号异常，但增强后 10 分钟延迟的三维 FLAIR 图像显示左侧内耳增强。增强后 4 小时延迟的三维 FLAIR 图像显示左侧整个耳蜗、前庭和半规管的增强更为明显。
在 AOM 并发浆液性迷路炎中，由于中耳内细胞因子和其他炎症介质的直接渗透以及血迷路屏障的破坏导致血清白蛋白漏入外淋巴液，外淋巴液的密度可能会增加。外淋巴液和内淋巴液的密度差异使半规管对重力敏感。重力还会产生浮力，导致壶腹内的内淋巴膜凹陷和帽状突移位。因此，在浆液性迷路炎的早期，头倾试验可能会引起持续向地性 DCPN，其方向随时间而变化。
