鳃裂囊肿的MRI和CT诊断

MRI and CT diagnosis of the branchial cleft cysts

目的 :讨论鳃裂囊肿的MR和CT表现及其诊断价值。方法 :对均经手术和病理证实的 11例鳃裂囊肿病人(第一鳃裂囊肿 2例 ,第二鳃裂囊肿 9例 )的CT或MRI的表现进行分析 ,并结合文献进行讨论。结果 :第一鳃裂囊肿表现为耳前区反复感染或瘘 ,其特征为瘘道与外耳道平行 ;第二鳃裂囊肿常表现为颈外侧部和颌下区无压痛囊性肿块 ,CT和MRI表现为薄壁、均质的囊性肿块 ,胸锁乳突肌受压向后外或向后移位 ,颈动脉间隙大血管向内或向后内移位 ,颌下腺向前移位 ,根据Bailey的分型 ,本组 9例中 2例属Ⅰ型 ,7例属Ⅱ型 ,囊肿在T1加权上呈低至高信号 ,T2 加权常呈高信号 ,囊壁强化的厚度取决于感染的程度。结论 :MR和CT对第一、二鳃裂囊肿的定位及其诊断具有重要价值。

Objective:To evaluate the MRI and CT characteristics of the branchial cleft cysts.Methods:11 cases with branchial cleft cyst proven by surgury and pathology,including 2 of first branchial cleft cysts and 9 of second branchial cleft dysts were collected.The MRI and CT findings were analysed.Results:The cysts of the first branchial cleft usually presented as recurrent inflammation and fistulas (sinus tract) around the ear.The fistula was characteristically found medial to the concha of the ear and parallel to the external auditory canal.Most second branchial cleft cysts usually appeared as painless and fluctuant masses in the lateral portion of the neck adjacent to the anteromedial border of the sternocleidomastoid muscle at the mandibular angle.These cysts were typically well circumscribed and homogeneous surrounded by a uniformly thin wall on CT and MRI.The cystic fluid varied from hypointense to slightly hyperintense relative to muscle on T 1WI and appeared usually hyperintense on T 2WI.Conclusion:MRI and CT are useful methods in the determination of location and nature of the branchial cleft cysts.