ranulas

Ranula is a form of mucocele that occurs in the floor of the mouth and is most often derived from the sublingual gland. The name, from Latin ranula meaning little frog, reflects the characteristic bluish, swelling appearance. Clinically, there are two main forms: oral (intraoral) ranula, which remains in the mouth, and cervical (plunging) ranula, which extends into the neck through the mylohyoid muscle.

Pathophysiology: Ranula results from rupture or obstruction of salivary ducts leading to mucin leakage into surrounding tissues (extravasation mucocele). It most often involves the sublingual gland or minor salivary glands of the floor of the mouth. An oral ranula presents as a soft, translucent, bluish swelling in the floor of the mouth; a plunging ranula may present as a neck mass with little or no oral swelling.

Clinical features: Slowly enlarging, painless swelling; may cause speech or swallowing difficulties if large; neck involvement in plunging ranula.

Diagnosis: Diagnosis is clinical, supported by imaging. Ultrasound can show a cystic lesion; MRI or CT best delineate extent and relation to the sublingual gland and neck structures. Fine-needle aspiration generally shows mucinous material. Differential includes branchial cleft cyst, thyroglossal duct cyst, lymphatic malformation, and other cystic neck lesions.

Treatment: Definitive management is surgical removal of the ranula with excision of the sublingual gland to minimize recurrence. Simple drainage or marsupialization has high recurrence. Alternatives include sclerotherapy (e.g., OK-432) or laser therapy in select cases. Plunging ranulas may require combined intraoral and transcervical approaches.

Prognosis: With appropriate gland excision, recurrence is uncommon. Ranulas are more common in children and young adults but can occur at any age.