The Appropriate Surgical Approach to Frontotemporal Dermoid Cysts in Adult Patients

Because frontotemporal dermoid cysts are superficial masses on the zygomaticofrontal suture, they are usually removed by simple direct excision in pediatric patients. Adult patients, however, require a more involved treatment approach because these cysts may be large and extend deeply into the surrounding tissue. From 2008 to 2015, 33 adult patients with frontotemporal dermoid cysts were treated in our clinic under a new treatment algorithm. Patients with a cyst smaller than 2 cm in diameter were treated using a direct excisional approach without a preoperative computed tomography (CT) evaluation. Patients with a cyst larger than 2 cm in diameter underwent a preoperative CT evaluation to determine the exact location of the cyst. If the cyst invaded the temporal fossa, a hemicoronal approach was used for excision. Cysts that did not cross the lateral orbital rim were removed using a direct excisional approach. Among the 33 patients in the study, 6 patients had cysts smaller than 2 cm in diameter, and 27 patients had cysts larger than 2 cm in diameter. Of the 27 patients with large dermoid cysts, 17 cysts showed temporal fossa invasion and 10 showed no signs of temporal fossa invasion. In all cases, the cyst was completely excised without rupture, and no instances of complications or recurrence were observed. In adults with frontotemporal dermoid cysts larger than 2 cm in diameter, preoperative CT evaluations should be performed. If the evidence suggests that a cyst has invaded the temporal fossa, a hemicoronal approach is required for complete excision.