Image findings of dermal sinus in the lateral buttocks

This case series showed the sonographic and magnetic resonance imaging findings of two patients with dermal sinuses in the lateral buttocks. According to the 2 present cases, and 8 cases previously reported, the distal sides of the sinuses may be connected to internal tissues, such as the subarachnoid, gluteal fissure, peritoneal cavity, or pelvic bone. Since it is difficult to predict the involvement of the distal side of a dermal sinus based on the dermal pit location, ultrasound and magnetic resonance imaging were postulated as a useful modality to aid evaluation. Based on these image findings, complete surgical resection was performed by surgeons.