Sphenofrontal intradiploic dermoid cyst with cutaneous dermal sinus tract.

We report the case of a 5-year-old boy who presented with a draining cutaneous pit temporal to the lateral canthus, with recurrent periorbital infections. MRI and CT revealed a sinus tract leading from the pit at the skin surface to a 5 mm lesion located in the sphenoid bone near the left sphenofrontal suture. Intraoperative facial nerve monitoring and a lacrimal probe inside the sinus tract were used to guide dissection to the cyst through a minimally invasive temporal approach, without need for neurosurgical intervention.