Demographics and clinical presentation
Although a congenital abnormality, they tend to present in early adulthood (10-40 years of age) often after minor trauma on infection. Second branchial cleft sinus or fistulas on the other hand present earlier.
Typically second branchial cleft cysts present as a rounded swelling just below angle of mandible, anterior to sternocleidomastoid (although the position is variable - see classification below).
The cyst is typically filled with mucoid material, is well circumscribed and other than presenting as a swelling, is asymptomatic. If infected however, then surrounding stranding and skin changes are evident.
Cysts can occur anywhere along the course of the second branchial apparatus, from the pharyngeal wall to the skin, as it passes laterally and inferiorly between the ICA and ECA. The angle of the mandible is a frequent location.
- rounded, sharply circumscribed
- fluid density centrally
- thin wall
- extension of the cyst wall between the ICA and ECA just above the carotid bifurcation (sometimes referred to as the notch sign) is said to be 'pathognomonic'.
- sharply demarcated
- posterior acoustic enhancement - 70% 3
- imperceptible walls - 82%
- echogenicity is variable 3
- anechoic - 41%
- homogeneously hypoechoic with internal debris - 24%
- pseudosolid - 12%
- heterogeneous - 23%
T1 - variable signal dependant on protein content
- high protein content : high signal
- low protein content : low signal
- T2 - usually high signal
- T1 C+ (Gd) - no enhancement in uncomplicated lesions
- superimposed infection
- paramedian thyroglossal duct cyst
- cystic lymph nodes
- vascular lesions
- neurogenic tumours
- dermoid cyst
- cavernous lymphangioma
- thyroid nodule / cyst
- 1. Lanham PD, Wushensky C. Second brachial cleft cyst mimic: case report. AJNR Am J Neuroradiol. 2005;26 (7): 1862-4. AJNR Am J Neuroradiol (full text) - Pubmed citation
- 2. Harnsberger HR, Mancuso AA, Muraki AS et-al. Branchial cleft anomalies and their mimics: computed tomographic evaluation. Radiology. 1984;152 (3): 739-48. Radiology (abstract) - Pubmed citation
- 3. Ahuja AT, King AD, Metreweli C. Second branchial cleft cysts: variability of sonographic appearances in adult cases. AJNR Am J Neuroradiol. 2000;21 (2): 315-9. AJNR Am J Neuroradiol (full text) - Pubmed citation
- 4. Koeller KK, Alamo L, Adair CF et-al. Congenital cystic masses of the neck: radiologic-pathologic correlation. Radiographics. 19 (1): 121-46. Radiographics (full text) - Pubmed citation
- 5. Salazar JE, Duke RA, Ellis JV. Second branchial cleft cyst: unusual location and a new CT diagnostic sign. AJR Am J Roentgenol. 1985;145 (5): 965-6. AJR Am J Roentgenol (citation) - Pubmed citation
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|2nd branchial cleft cyst||✓|
|Second branchial cleft cysts||✗|
|2nd branchial cleft cysts||✗|