8. Imaging Findings
• Best diagnostic clue: Cystic mass around pinna and EAC (type
I) or extending from EAC to angle of mandible (type II)
• Well-circumscribed, non enhancing or rim-enhancing, low-
density mass
• If infected, may have thick enhancing rim or be dense internally
Top Differential Diagnoses
• *Benign Lymphoepithelial Cysts
• *Venolymphatic Malformation (VLM)
• *Suppurative Adenopathy/Abscess
• *Nontuberculous Mycobacterial Adenitis
First Branchial Cleft Cysts
10. First Branchial Cleft Cysts
• Accounts for 8% of all branchial
apparatus remnants
• Most common location for 1st BCC to
terminate is in EAC between its
cartilaginous & bony portions
11. Second Branchial Cleft Cysts
• Most Common (90%) branchial anomaly
• Painless, fluctuant mass in anterior triangle
• Inferior-middle 2/3 junction of SCM, deep to
platysma, lateral to IX, X, XII, between the internal
and external carotid and terminate in the tonsillar
fossa
12. Second Branchial Cleft Cysts
Imaging Findings
• Low density cyst with non enhancing wall & surrounding soft
tissues, unless infected
• If infected, wall is thicker & enhances with surrounding soft
tissues appearing "dirty" (cellulitis) or internally dense
Top Differential Diagnoses
• Lymphangioma
• Thymic cyst
• Suppurative jugulodigastic node
• Cystic vagal schwannoma
• Cystic malignant adenopathy (ALWAYS CONSIDER THIS
POSSIBILITY IN ADULTS!)
14. Second Branchial Cleft Cysts
• * Epidemiology: 2nd BCC account for > 90% of all branchial cleft
anomalies in teens and adults, 66-75% in children
• * Most common signs/symptoms: Painless, compressible lateral neck
mass in child or young adult
• * Neck mass often chronic, recurrent, increasing in size with upper
respiratory tract infection
• * Beware an adult with first presentation of "2nd BCC”
• * Mass may be metastatic node from head & neck SCCa primary tumor
15. Third Branchial Cleft Cysts
• Rare (<2%)
• Similar external presentation to 2nd BCC
• Internal opening is at the pyriform sinus, then
courses cephalad to the superior laryngeal nerve
through the thyrohyoid membrane, medial to IX,
lateral to X, XII, posterior to internal carotid
17. Third Branchial Cleft Cysts
Imaging Findings
*Best diagnostic clue: Unilocular thin-walled cyst in posterior cervical
space (posterior triangle)
*May occur anywhere along course of 3rd branchial cleft or pouch
Top Differential Diagnoses
* 2nd branchial cleft cyst
* 4th branchial cyst
* Lymphangioma
* Infrahyoid thyroglossal duct cyst
* Suppurative adenopathy
* External laryngocele
* Cystic-necrotic lymph node
18. Fourth Branchial Cleft Cysts
• Courses from pyriform sinus apex
caudal to superior laryngeal nerve, to
emerge near the cricothryoid joint, and
descend superficial to the recurrent
laryngeal nerve.
53. • Myositis ossificans (MO) is a benign process
characterised by heterotopic ossification
usually within large muscles.
• CT SCAN demonstrating mineralisation
proceeding from the outer margins towards
the centre. The cleft between it and the
subjacent bone is usually visible.
