mucoceles

A mucocele is a benign lesion that results from disruption of a minor salivary gland duct and the accumulation of mucin in the surrounding connective tissue. There are two main types: the mucous extravasation (or mucous extravasation cyst) and the mucous retention cyst. Extravasation mucoceles are the most common and occur when duct rupture allows mucin to spill into the tissue, where it is surrounded by granulation tissue but lacks an epithelial lining. Retention cysts arise from duct obstruction causing dilation of the duct and are lined by epithelium, representing a true cyst rather than a pseudocyst.

Clinically, mucoceles typically present as painless, fluctuant, non-ulcerated swellings of the mucosa. The lower lip is the most frequent site in the mouth, but they can occur on the buccal mucosa, tongue, floor of the mouth, and other mucosal surfaces. They may appear bluish or translucent and can change in size over time. They are common in children and young adults and are often linked to local trauma, such as lip biting or screen-cavity irritation.

Diagnosis is usually clinical, supported by history and, if needed, aspiration showing viscous, mucinous material. Imaging is rarely necessary but can help distinguish from other lesions. Histology after excision shows mucus pools with granulation tissue for extravasation mucoceles or a true epithelial lining for retention cysts.

Treatment generally involves surgical excision of the mucocele along with adjacent minor salivary glands to reduce recurrence. Alternatives include marsupialization or laser treatment in selected cases. Prognosis is excellent, with recurrence more likely if glandular tissue is incompletely removed. Recurrence risk is lower for retention cysts.