广泛性耳蜗耳硬化症：CT-MRI相关性及对比增强的诊断价值。

文献信息

中文摘要

背景： 耳硬化症是耳囊的一种慢性疾病。其特征为异常骨重塑，可能超出窗区并累及耳蜗及骨迷路的其他结构。耳硬化症主要有两种类型——窗后型（耳蜗型）和窗型，其中窗型更为常见。方法：我们报告一例59岁女性广泛性双侧耳蜗耳硬化症的多模态影像学表现，该患者患有慢性双侧感音神经性听力损害，右耳分级为3级，左耳为完全性耳聋。结果：高分辨率计算机断层扫描（CT）显示广泛的双侧3级耳海绵化改变，累及多个耳蜗转，并向前庭、窗前裂、卵圆窗及外半规管延伸。增强前T1加权磁共振成像（MRI）显示轻度耳蜗周围高信号，提示耳海绵化骨重塑。匹配的增强后T1加权成像表现与双侧耳囊耳蜗周围及迷路周围强化相对应，这与活动性耳海绵化骨重塑的发现相符。T2加权序列显示迷路内液体信号保留，且无相应的耳囊异常。结论：尽管T2加权序列在直接显示耳海绵化改变方面有限，但其有助于评估形态并排除其他病变。本病例说明了CT和MRI在显示晚期活动性耳蜗耳硬化症中的互补作用，并提请关注可能被忽视的MRI表现，尤其是增强后T1加权图像中的表现。

英文摘要

Otosclerosis is a chronic disorder of the otic capsule. It is characterized by abnormal bone remodeling, which may extend beyond the fenestral region and involve the cochlea and other structures of the bony labyrinth. There are two main types of otosclerosis-retrofenestral (cochlear) and fenestral, the latter of which is much more common. We present multimodal imaging findings of extensive bilateral cochlear otosclerosis in a 59-year-old woman with chronic bilateral sensorineural hearing impairment, classified as grade 3 in the right ear and complete deafness in the left ear. High-resolution computed tomography (CT) demonstrated extensive grade 3 bilateral otospongiotic changes involving multiple cochlear turns and extending toward the vestibule, fissula ante fenestram, oval window, and the lateral semicircular canal. Pre-contrast T1-weighted magnetic resonance imaging (MRI) showed mild pericochlear hyperintensity, suggestive of otospongiotic bone remodeling. Matching post-contrast T1-weighted imaging findings corresponded with bilateral pericochlear and perilabyrinthine enhancement of the otic capsule, which is associated with findings compatible with an active otospongiotic bone remodeling. T2-weighted sequences showed preserved fluid signal within the labyrinth and no corresponding otic capsule abnormality. Although limited for directly depicting otospongiotic changes, the T2-weighted sequence was useful for assessing morphology and excluding alternative pathology. This case illustrates the complementary role of CT and MRI in demonstrating advanced active cochlear otosclerosis and draws attention to MRI findings that might otherwise be overlooked, especially those in post-contrast T1-weighted images.