Recurrent sublingual ranula or saliva leakage from the submandibular gland? Anatomical consideration of the ductal system of the sublingual gland.

PURPOSE: Some believe that the recurrence of sublingual ranula results from incomplete removal of the sublingual gland (SLG), but recurrence remains in some patients who undergo repeated excision of the remnant SLG, and the final solution to the recurrence is to remove the ipsilateral submandibular gland (SMG). In the authors' experience, preoperative aspirate from a sublingual ranula was a thick mucus-like fluid resembling egg white, whereas that from recurrent cyst after removal of the SLG was thin serous fluid. Based on the difference of the aspirated fluids, the authors speculated that the recurrent cystic mass might not be a ranula, but rather iatrogenic saliva leakage from the SMG through the previous surgically damaged excretory duct of the SLG (Bartholin duct) that opens into the SMG duct (Wharton duct).

MATERIALS AND METHODS: A gross anatomic study was performed of the ductal system of the SLG and the anatomic communication between the Bartholin duct and Wharton duct.

RESULTS: Four anatomic SLG duct variants were found. 1) The SLG has 1 Bartholin duct that seems to fuse with the Wharton duct but does not join the Wharton duct, running parallel to the Wharton duct and opening at its own orifice adjacent to and a short distance from the orifice of the Wharton duct (35.8%). 2) The SLG has 1 Bartholin duct that empties into the middle section of the Wharton duct (32.1%). 3) The SLG has 2 Bartholin ducts, one of which joins the Wharton duct and the other opens at its own orifice near that of the Wharton duct on the floor of the mouth (7.1%). 4) The SLG has many fine ducts (Rivinus ducts) that open at the floor of the mouth with no relation to the Wharton duct (25.0%). Of the 4 anatomic SLG duct variations, types 2 and 3 form immediate anatomic communication between the Bartholin duct and Wharton duct (39.2%).

CONCLUSIONS: Several conclusions can be made from the present anatomic findings. 1) A certain proportion of Bartholin ducts open into the Wharton duct, and "recurrent ranula" after removal of the SLG can result from iatrogenic saliva leakage from the SMG through the surgically severed Bartholin duct if the aspirated fluid from the "recurrent cyst" is a thin seriflux. 2) The Bartholin duct emptying into the Wharton duct should be ligated during removal of the SLG to prevent local saliva accumulation from the SMG or even caudal "recurrence" as plunging ranula. 3) The surgical incision for SLG removal should be sutured loosely so that the surgically severed Bartholin duct with communication to the Wharton duct can reopen at the floor of mouth as an outlet for possible saliva leakage from the SMG and saliva accumulation can be avoided.