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OMFS-0121Salivary GlandintermediateFloor of mouth / submandibular region

Bluish floor of mouth swelling with a cervical component

22-year-old female

Draft — educational study aid, pending faculty review.

§Chief complaint

Swelling under the tongue and in the neck for 4 months

§Medical & dental history

  • 01Nil relevant
  • 02Nil relevant

§Clinical examination

  • 01Soft, bluish, translucent swelling of the left floor of mouth elevating the tongue
  • 02Painless soft swelling in the left submandibular region, non-tender, no skin change
  • 03Wharton duct orifice patent with normal saliva
  • 04No trismus or airway compromise

§ figuresFigures (3)

Fig. 1Ranula in a human

“Ranula human 09” · Ph0t0happy · CC BY-SA 3.0 · Wikimedia Commons

Fig. 2Ranula in 55-year-old woman.

“Ranula” · Klaus D. Peter, Wiehl, Germany · CC BY 2.0 de · Wikimedia Commons

Fig. 3Ranula on the floor of the mouth

“Ranula large” · Dikkisherpa5 · CC0 · Wikimedia Commons

Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Ranula figures pending faculty review.

§Differential diagnosis

Plunging ranulaFloor of mouth swelling with a cervical extension through mylohyoid
Simple ranulaConfined to the floor of mouth
Dermoid cystMidline, doughy, no bluish hue
Cystic hygromaPresent from childhood, multiloculated, transilluminates

§Final diagnosis

Plunging (cervical) ranula arising from the left sublingual gland

A ranula that extends below the mylohyoid presents as a combined oral and cervical swelling. Being a pseudocyst of extravasated mucus from the sublingual gland, definitive treatment requires removal of that gland, not just the cyst.

§Investigations

  • 01Ultrasound neck — anechoic collection extending through the mylohyoid
  • 02MRI — high T2 signal 'tail sign' passing posterior to mylohyoid
  • 03Aspiration — viscous, mucin-rich fluid with high amylase

§Treatment plan

  • 01Excision of the ipsilateral sublingual gland with evacuation of the pseudocyst
  • 02Intraoral approach preferred; cervical approach rarely needed
  • 03Counsel on lingual nerve and Wharton duct risk

§Surgical procedure

  • 01Intraoral floor of mouth incision lateral to the duct
  • 02Wharton duct and lingual nerve identified and preserved
  • 03Sublingual gland excised, pseudocyst decompressed
  • 04No drain; primary closure

§Histopathology report

Mucin pool bounded by granulation tissue without epithelial lining, with adjacent sublingual gland tissue. Consistent with ranula (mucous extravasation pseudocyst).

§Follow-up & outcome

  • 01Cervical swelling resolved within 3 weeks
  • 02Transient lingual paraesthesia resolved by 6 weeks
  • 03No recurrence at 18 months

§Clinical pearls / learning points

  • 01Marsupialisation alone has high recurrence; sublingual gland excision is the definitive treatment.
  • 02A neck lump with no oral component can still be a plunging ranula — check the amylase in the aspirate.
  • 03The lingual nerve crosses under Wharton duct — identify both before dissecting.

§References

  • Zhao YF et al. Clinical review of ranula management.

§Similar cases

OMFS-0116

Slow-growing painless lump in the parotid

OMFS-0119

Dry mouth and bilateral parotid enlargement

OMFS-0118

Mealtime swelling of the submandibular gland

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