Abstract: Objective To summarize the clinical and magnetic resonance imaging （MRI） characteristics of sacrococcygeal pilose sinus. Methods Five patients with pathologically confirmed sacrococcygeal pilose sinus were retrospectively analyzed, including clinical data and MR images. Results Sacrococcygeal subcutaneous sinus could be found in all 5 cases, with the ostium located in internatal cleft skin at the level between the 5^th sacral and 3^rd coccygeal vertebrae. The sinus extended upward subcutaneously from sacrococcygeal region, with tortuous or irregular shape. The wall of sinus was thick, hyperintense on T2WI-FS and hypointense on T1WI. The lumen was hypointense on both T2WI-FS and T1WI when there is no pus or fluid and intralumen pus and fluid were hyperintense on T2WI-FS and hypointense to slight hyperintense on T1WI. Edema was seen in surrounding soft tissue. The wall and surrounding soft tissue of the sinus showed significant enhancement in the case of infection. No sacrococcygeal bone or anal canal was involved. Conclusion MRI can accurately show the position, scope of sinus and surrounding tissues, so it has important clinical value in the diagnosis of sacrococcygeal pilose sinus.

Key words: sacrococcygeal, magnetic resonance imaging, pilonidal sinus

摘要： 目的 总结骶尾部藏毛窦的临床特点及MRI影像学特征。方法 回顾性分析5例经病理证实的骶尾部藏毛窦患者的临床资料及其MRI表现。结果 5例病灶均为骶尾部皮下窦道;窦口位于骶5至尾3椎体水平臀间裂皮肤处;窦道行走于骶尾部皮下,向上走形,走形迂曲或形态不规则;窦道管壁较厚,T2加权成像脂肪抑制（T2WI-FS）呈高信号,T1WI呈低信号,管腔无积脓积液时,T2WI-FS 及T1WI均呈低信号,管腔内积脓或积液时,T2WI-FS呈高信号,T1WI上呈低信号-稍高信号;窦道周围常出现软组织水肿;病灶易合并感染,窦道管壁及周围软组织增强呈明显强化;病变均未累及骶尾骨及肛管。结论 MRI可准确显示藏毛窦的窦道位置、范围及与周围组织之间的关系,在骶尾部藏毛窦的诊断上具有重要的临床价值。

关键词: 骶尾部, 藏毛窦, 磁共振成像