Are the patients with anatomic variation of the sublingual/Wharton's duct system predisposed to ranula formation?

OBJECTIVE: To evaluate ranula development according to anatomic variation of the ductal system of sublingual gland (SLG), especially the presence of Bartholin's duct.

METHODS: The anatomic variation of SLG duct was prospectively investigated and compared between 55 consecutive patients with ranulas treated by SLG excision (group 1) and another 15 consecutive patients undergoing similar surgeries for other conditions (group 2). The ductal structures of SLGs and submandibular glands (SMG) were also compared between the pediatric patients and adult patients with ranulas.

RESULTS: In 32 of 55 patients with ranulas (58.2%) and 1 of 15 patients without ranulas (6.7%), the SLG showed an anatomic variation of the main duct called Bartholin's duct structure (P<0.01). Seventeen of 22 (77.3%) pediatric patients with ranulas had Bartholin's ducts and 15 of 33 (45.5%) adult patients with ranulas had Bartholin's ducts (0.01<P<0.05), but Bartholin's duct which opens near to the orifice of Wharton's duct was not found in this study population. Plunging ranulas that extravasate deep to the mylohyoid were observed in the 6 patients (4 children and 2 adults). There was no recurrence in all cases with ranulas.

CONCLUSIONS: Congenital anatomic variation of the ductal system of the SLG might be a possible cause of ranulas in the patients with simple ranulas, especially in pediatric patients. Surgical resection of the SLG is a better treatment choice for ranulas than other conservative treatments.