Intralabyrinthine Schwannoma: an Uncommon but Underdiagnosed Entity
YH Woo, SS Lo
Hong Kong J Radiol 2013;16:e17-20
DOI: 10.12809/hkjr1312124
Intralabyrinthine schwannoma is an uncommon tumour arising from the vestibulocochlear nerve within the cochlear, vestibule, or semicircular canals. Intralabyrinthine schwannomas are classified according to the location, and ‘intracochlear’ is the commonest subtype. Patients frequently present with progressive hearing loss. Imbalance or vertigo are also common presentations. On magnetic resonance imaging, the tumour will be shown as a filling defect of the labyrinth on T2-weighted images. Intense contrast enhancement is also evident. Intralabyrinthine schwannoma was believed to be under-reported in the past, but with recent advancements in magnetic resonance imaging technology, sensitivity for the detection of this tumour has increased. Radiologists should be aware of intralabyrinthine schwannoma when screening patients with hearing or balance disorders.
中文摘要
迷路內神經鞘瘤：一種罕見的但屬診斷不足的病症
吳業軒、盧承迅
迷路內神經鞘瘤是起源於耳蝸、前庭或半規管內的前庭蝸神經的一種罕見腫瘤。根據病變部位分類，「耳蝸內」是最常見的迷路內神經鞘瘤亞型。患者一般會出現進行性聽力受損，而平衡失調或眩暈亦是常見的臨床表現。腫瘤在磁共振T2加權像上顯示為迷路充盈缺損，亦會有明顯的對比增強。以往迷路內神經鞘瘤病例被認為報導不足，但隨着磁共振成像技術近來的進步，對此腫瘤的檢測靈敏度有所增加。放射科醫生遇到聽力受損或平衡失調的病人時，應意識到可能是患有迷路內神經鞘瘤。