SAEM Clinical Images Series: An Expanding Painful Neck Mass

Deep space infections of the neck can be categorized by the fascial layer involved: superficial, middle, and/or deep. Infections in the deep- superficial and deep-middle fascia include Ludwig’s angina, mandibular abscesses, and parotitis. These are most often caused by dental infections, and can cause compression resulting in airway compromise, thrombophlebitis, and narrowing of the great vessels of the neck. Infection of the deep layer of the cervical fascia, such as in retropharyngeal or parapharyngeal abscess, communicates directly with the mediastinum, and can rapidly progress to severe mediastinitis. This patient’s imaging shows cystic structures with no flow seen within or around the structures, and shows the fluid collection extending from the sublingual space, communicating with the submandibular space and base of the mouth. This was determined to be an infected plunging ranula.

Take-Home Points

• A simple ranula (occurs in 1 out of 5000 individuals) presents as a painless bluish saliva containing cyst visualized below the tongue.
• A “plunging” (or “diving”) ranula is a rare condition caused by direct leakage of salivary fluid from the sublingual gland at the base of the mouth into the soft tissues of the neck.
• Treatment involves needle aspiration and surgical excision. About 50% of cases recur without excision of the submandibular gland.