Presentation
Right-sided fluctuant swelling of the neck. Past history of branchial cleft cyst partially removed. Previously infected lymph node and trigeminal neuralgia.
Patient Data
Deep to the right SCM muscle sternocleidomastoid is a relatively low density ?cystic mass, separate to the parotid gland and carotid sheaths, (20 x 25 x 17 mm) ~20 Hounsfield units.
The mass is well circumscribed and superiorly appear to be a number of branching or tubular structures of similar density, which is atypical for a branchial cleft cyst. No fat stranding seen around the mass.
A couple of lobulated lesions, of somewhat lower density (-20 HU) are seen between the anterior border of SCM and the overlying skin.
• Large cystic mass seen centred in the right perivertebral compartment (6.8 x 2.7 x 6.2cm).
• Large septated cystic component with many smaller complex cystic elements, extending to the region of the right carotid sheath and posterior parotid region.
• There are further smaller cystic components in the subcutaneous fat within the lateral neck.
• Thin peripheral enhancement, including in the septation within the large cystic component.
Case Discussion
Case submitted by Dr Smita Deb and A/Prof Pramit Phal.
Initially a CT neck was done with the differential diagnoses being: branchial cleft cyst vs veno-lymphatic malformation.
However, given the variegated cystic appearance on MRI as well as the branching structures near the mass on CT (atypical for branchial cleft cyst), a venolymphatic malformation is favoured over a complicated branchial cleft cyst.
USS + FNA was done which confirmed a branchial cleft cyst.