a retention cyst or mucocele of the floor of the mouth involving obstruction of the submaxillary or sublingual glands and usually unilateral that is slowly enlarging. also called a sublingual cyst or ptyalocele.


one published report of prenatally diagnosed ranula could be found. at 26 weeks gestation, a uniform, concentric, cystic appearing mass was seen arising from the mouth. early surgical intervention produced excellent results. the sublingual location of a ranula should be an important discriminator in differential diagnosis and therefore independence of this mass from the normal-sized tongue should be sought on profile and coronal views.

differential diagnosis

macroglossia should be easily discriminated as an enlarged, protuberant structure visible through a persistently open mouth. lingual thyroid generally presents as a small more solid appearing nodule in front of the terminal sulcus of the tongue. choristoma of the tongue is a cystic mass containing gastric or intestinal mucosa. haemangiomia of the tongue may cause enlargement with cystic vascular spaces detected by ultrasound. lymphangioma of the tongue may present with enlargement, irregularity and prominent median sulcus of the tongue.

sonographic features

smooth regular cystic mass arising from floor of the mouth and discrete from fetal tongue

associated syndromes


gorlin rj, sedano ho in: human malformations and related anomalies, volume ii oxford university press