Ranula

A ranula is a fluid-filled swelling caused by saliva collecting in the floor of the mouth, usually beneath the tongue. It often forms when saliva leaks from or cannot drain normally from a salivary gland. A ranula under the tongue may look soft, clear or bluish. Ranulas can occur in children or adults.

A ranula develops when saliva from the sublingual gland leaks into nearby tissue or cannot drain through its duct normally. The trapped saliva forms a mucus-filled cavity in the floor of the mouth.

Possible triggers include trauma, surgery or inflammation that affects a salivary duct. However, the exact cause is not always clear, and some people develop a ranula without a known trigger.

Ranulas are not generally caused by poor oral hygiene. Keeping your mouth clean is important for overall health, but it does not usually prevent this type of salivary swelling.

A clinician examines the mouth, tongue and neck and asks when the swelling began, how it has changed and whether it affects eating, speaking or swallowing. They assess whether the lump feels soft and fluid-filled and whether it appears connected with a salivary gland.

Ultrasound, CT or MRI may be used to define the cyst’s size and extent, especially when a plunging ranula extends into the neck. Imaging can also help rule out other causes of a lump in the mouth or neck.

Ranula treatment depends on the swelling’s size, symptoms, whether it extends into the neck and whether it has returned after treatment. A small, painless ranula may be monitored, while drainage or surgery may be considered for persistent, large or bothersome swellings. Simple drainage can relieve the swelling but may recur; definitive surgery may reduce the chance of recurrence.

Observation

Observation may be offered for a small ranula that is painless and does not interfere with eating, speaking or swallowing. A clinician monitors its size and symptoms, and reassessment is needed if it grows, becomes painful, returns or causes swallowing or breathing problems. Some ranulas remain stable, while others need a procedure if they persist.

Drainage or Marsupialization

Ranulas are usually benign and treatable, but the swelling can return if the underlying salivary duct or gland problem remains. Recurrence is more likely when treatment only drains the collected fluid without addressing the source.

Follow-up may include checking the mouth and neck, reviewing symptoms and watching for a new or returning swelling. The prognosis is generally good when breathing, swallowing and speech are preserved, and a clinician can recommend further treatment if the ranula comes back.

Arrange a medical or dental assessment for a new swelling under the tongue, a neck lump, or a swelling that persists or grows. You should also seek evaluation for symptoms that affect eating, speaking or swallowing. Rapidly increasing swelling, trouble breathing or inability to swallow saliva requires urgent medical attention.