Incidental finding in a 70-year-old-lady. Well-defined midline soft tissue swelling in the floor of the mouth 18 x 11 mm.
At first look it appears that the swelling is arising from the dorsum of the tongue. However, on searching more carefully you will notice that the lower anterior tooth is a few mm superior to the floor of the mouth which is seen as an undulating boundary between air and soft tissue.
The most posterior extent of the floor ends at the anterior boundary of the vertical soft tissue swelling. The swelling is of course the anterior portion of the tongue which has been raised, perhaps in response to “Put your tongue to the roof of your mouth.”
The moral of the story is do not make an immediate diagnosis until you have identified the normal anatomy in the volume to ensure everything is where it should be!
Dr Douglas K Benn DDS, PhD, Dipl. Dental Radiology (Royal College of Radiologists, England)
Oral and Maxillofacial Radiologist