头颈区去神经性肌萎缩的CT与MRI表现及其临床意义

Denervation Muscular Atrophy in the Head and Neck:CT and MRI Evaluation

本文报告８例头颈区去神经性肌萎缩的ＣＴ和ＭＲＩ表现，旨在评价其临床意义。引起肌萎缩的原因包括颈静脉孔区肿瘤４例（颈静脉球瘤、转移瘤各２例），鼻咽癌２例，中颅凹区脑膜瘤１例，上颌窦囊腺癌转移至咽旁１例。ＣＴ和ＭＲＩ表现为特定的颅神经运动支支配区肌肉轮廓缩小，脂肪间隙增宽，病程较长者表现为受累肌群完全为脂肪组织取代；３例根据肌萎缩征象发现原发病变。作者认为：认识去神经性肌萎缩的ＣＴ、ＭＲＩ表现可避免误为其它异常；根据肌萎缩的范围、分布可有针对性检查某些区域，以发现原发病变。

Eight cases of denervation muscular atrophy(DNMA) secondary to tumor involving the motor division of the cranial nerves were reported. DNMA were caused by jugular fossa tumor (n=4), nasopharyngeal carcinoma (n=2),meningioma of middle cranial fossa(n=1),and adenoid cystic carcinoma of maxillary sinus metastasis to parapharyngeal space(n=1).Asymmetry of the fat planes and decreasing the muscle bulk were the early signs of atrophy on CT and MRI. After 3～4 months of onset,the volume decrease and fatty infiltration of the specific muscle group innervated by the affected nerves were obvious. In three cases, the atrophic muscles identified on the images were the only clue to the presence of a pathologic condition, The authors concluded that recognition of the atrophic pattern could prevent misinterpretation of the CT and MRI appearances and direct the imaging examination to the course of the compromised cranial nerve.