Is a cystic swelling in the floor of the mouth.
The term Ranula is derived from the Latin word Rana meaning frog belly. The cyst looks like belly of a frog.
Theories:
These are retention cysts in relation to mucous secreting glands of the sublingual mucous membrane. (Glands of Blandin and Nuhn).
Retention cysts in relation to sublingual salivary glands.
The plunging variety may be due to a forward prolongation of an un-obliterated part of cervical sinus.
Types:
A. Simple.
B. Plunging: (complex, deep).
A.) Simple: Ranula is relatively localized and is a superficial dilated segment of a blocked or damaged sublingual gland duct.
B.) Plunging (complex): Results from extension of oral variety or from the escape of mucus from a posterior sublingual gland which burrows along the posterior margin of mylohyoid down into submandibular region to form a cervical swelling.
Plunging Ranula right.
Clinical features:
Found in childhood.
Situated on one side of frenum linguae either on the floor mouth, or under surface of tongue. A big cyst may encroach the other side of the floor of mouth deep to frenum linguae.
Mucous membrane is freely mobile on the cyst.
Cyst is bluish in color.
Brilliantly transilluminant. Presence of white strands amidst reddish glow indicating presence of deep lingual veins along the wall, cyst or Wharton’s duct.
Pathology:
a) The wall is lined by epithelium (cuboidal, columnar, and ciliated) or by fibrous tissue.
b) Fluid is jelly like and colorless.
Treatment:
Total excision: This is ideal but difficult as the cyst almost always ruptures during dissection due to its very thin wall.
Partial excision with Marsupialization: This technique prevents recurrence.
Plunging Ranula has to be approached from neck. The cyst is dissection between mylohyoids. Here, total excision along with removal of sublingual gland done.