The Role of Preoperative Imaging for Midline Congenital Upper Lip Sinus Tracts.

Objective: To describe 3 cases of midline congenital upper lip sinus (MCULS) and review current literature to inform risk of intracranial involvement in the context of this rare congenital facial anomaly.

Materials and methods: A limited case series with chart review is presented. A literature search was conducted to review proposed theories of the embryology of MCULS and to determine the relative frequency of cephalic extension.

Results: Including the 3 new cases presented herein, there have been 42 cases of MCULS described in the literature over the past 53 years. Thirty-nine cases (93%) underwent surgical excision, with 2 of these cases (4.7%) demonstrating cephalic extension of the fistula tract beyond the maxillary crest with termination at the anterior skull base. However, 95% (37/39) of surgically excised MCULS cases demonstrated a more limited depth of extension, with termination of the tract at or below the anterior nasal spine.

Conclusions: The MCULS anomaly is rare, with fewer than 50 cases reported in the literature. Only 2 cases have been described with extension of the MCULS superior to the anterior nasal spine and into the nasal septum. It is the authors' opinion that preoperative neuroimaging is not routinely required for MCULS. However, if extension of the sinus tract beyond the anterior nasal spine is noted intraoperatively, the surgeon should consider aborting the case and obtaining appropriate neuroimaging.