I read with disappointment and alarm the article by Markou et al. entitled “Giant submandibular gland mucocele as a complication of previous sialolith removal”.

The disappointment arises because there have been so many publications this century that have continued to clarify the aetiology, pathogenesis and management of what the authors misdiagnosed and was a plunging ranula that originated from the sublingual gland .

The removal of the sialolith in Wharton’s duct damaged a duct of Rivinus leading to extravasation of saliva from one of the numerous glands that constitute the lesser sublingual gland . Extravasated saliva from the sublingual gland is not always noticed because it is removed by macrophages and lymphatic drainage, but if the balance between extravasation and removal alters, a clinical ranula can occur as in the present case . The statement that “The radiographic presence of the ‘tail sign’, diagnostic of a sublingual plunging ranula, was present” even confirms the origin from the sublingual gland. Damage to Wharton’s duct can be followed by extravasation of saliva from the submandibular gland, but this is prandial, and does not persist as the submandibular gland atrophies because of fibrosis associated with the extravasated saliva, to which the sublingual gland is resistant .

The alarm arises because the removal of the plunging ranula, which can be difficult and involves a cervical approach, has been repeatedly shown to be unnecessary because it is a cyst lined by inflamed granulation tissue, which will be resorbed once the supply of saliva from the sublingual gland is stopped by removal of the sublingual gland or by one of several conservative procedures .

There is much more that is misleading in this article , such as: mucous retention cysts can cause ranulas, which is not so; treatment options for ranulas include radiation, which is not so and would today appear to represent malpractice.

The authors state that although Harrison et al. rejected the theory of the origin of the mucocele from the submandibular gland, Bhaskar et al. detected mucoceles 9 days after harming the submandibular ducts . Bhaskar et al. and several other groups produced extravasation mucoceles of short duration in mice and rats by severing the submandibular and sublingual ducts, which run together to the submandibular and sublingual glands, which are in a common capsule. Thus the sublingual gland would have been partly responsible for the extravasation, which was of short duration, and this was extensively discussed by Harrison and Garrett in the article quoted by the authors .

Several other reports of submandibular mucoceles are quoted , but unfortunately the quoted authors have made the same misdiagnosis as Markou et al. .