Findings:
Well defined cystic lesion with peripheral enhancement is seen in left sublingual space between mylohyoid muscle laterally and geniohyoid / genioglossus complex medially. The lesion descends inferolaterally via mylohyoid into the left submandibular space. No inflammatory changes of the surrounding soft tissue, no diffusion restriction.
There is no associated lymphadenopathy. Non-specific submandibular lymph nodes are seen bilaterally.
The parotid and submandibular glands are unremarkable.
The pharyngeal and glottic regions are normal. The parapharyngeal fat space is normal. The tonsils and adenoids are normal.
The visualised brain is unremarkable. The paranasal sinuses and mastoid air cells are clear.
No bony abnormality is seen.
Impression:
Bulky, cystic lesion centred on the floor of the mouth on the left side and extending into the left submandibular region, likely in keeping with a plunging ranula, DDX floor of mouth dermoid cyst.