Plunging and sublingual-plunging ranulas are salivary gland diseases often encountered. Their onset is attributed to a change in saliva flow patterns due to surgical scarring. We report the case of a sublingual-plunging ranula in a 30-year-old woman in whom saliva pooling was observed in the supraclavicular fossa and superior mediastinum. She had experienced several sublingual ranula recurrences despite repetitive marsupialization at her former clinic and was therefore referred to our hospital. We noticed painless swelling of the left oral floor and neck at the first visit, and there was a mild bulge on the left supraclavicular fossa. Oral cavity examination showed a painless and well-circumscribed swelling extending from the left oral floor to the midline. T2-weighted magnetic resonance (MR) imaging revealed a well-defined, homogeneous, high-signal lesion from the left mouth floor/sublingual region to the neck/supraclavicular fossa. Only sublingual gland excision was performed, and the pooled saliva appeared and was naturally reabsorbed on the MR image taken 3 months postoperatively. As of 2 years 3 months postoperatively, there has been no evidence of recurrence, and a favorable outcome was achieved.
