腮裂囊肿

Clinical symptom
• Mostly occur in children and teenagers • BCCs are typically a painless compressible mass ,growing slowly. • They may occasionally become infected and present with fever, induration, and tenderness , become larger suddenly.
triangle; anteromedial of the sternocleidomastoid; inner side of the salivary gland; anterolateral of the carotid sheath;
• Infection: the signal of the mass or the wall become
CT plain scan： Cystic low density area in the left carotid sheath About 2. 6cm X 2.4cm, well-defined, CT value:22Hu。CT enhangcement : the mass show a circular enhancement , CT value :62.6Hu, Well-defined , the inner of the mass have no enhancement , CT :22.2Hu
The fourth branchial cleft cyst
Very rare • Locate in the inner side of the subclavian artery • Usually shows a sinus tract ,but not fistula or cyst
female，20 years old， the left second branchial cleft cyst ;
Thyroglossal cyst
Schwannoglioma
• Low density area with high density change is one of the most distinctive performance for neck schwannoma • Pointlike change is a characteristic CT enhanced performance for neck schwannomas
essential points for MRI diagnosis
• an oval or round cystic mass, well-defined, go along with the sternocleidomastoid,the adjacent structures compressed;
•
Type
I
II
Ⅳ
The third branchial cleft cyst
• very rare • usually locate in the posterior of the common carotid artery or internal carotid artery，between the hypoglossal and the glossopharyngeal nerve
Case discussion
Tian jin first central hospital By Ji dongxu head group 2012-3-27
History
• Female • a painful mass in the right neck for half and a month • bilateral tonsil resection ten years ago
T2WI: axial,a oval cyst in the inner side of the left sternocleidomastoid， homogeneous hyperintense;
T1WI: homogeneous hyperintense;
Enhancement:the wall of the cyst slightly enhanced
• Signal: mostly longT1 ,and long T2 singal
;some slightly hyperintense on T1WI, depends on the ingredient of the fluid
• Location: in the anterior cervical
• the upper pole of the parotid gland • similar to parotid gland cyst • communicate with external auditory canal
The second branchial cleft cyst
• About accounting for 90%of BCCs; • usually occur in the period of 10 to 40 years old • often locate in lateral to the carotid sheath ,anteromedial to the sternocleidomastoid • medial beaking of the cyst
higher , rough borders; slightly hypointense on T1WI, slightly hyperintense on T2WI ; the wall can be enhanced
ቤተ መጻሕፍቲ ባይዱ
DDX
• • • • Thyroglossal cyst cystic lymphangioma parotid cyst cystic schwannoma
Contrast-enhanced CT
A 48-year-old woman presents with a slowly enlarging mass in the right upper neck
Types I–IV
• Ⅰ： the cyst is superficial to the anterior border of the sternocleidomastoid muscle • Ⅱ： the cyst is adjacent to the carotid sheath • Ⅲ： the cyst passes between the internal and external carotid arteries and extends to the lateral wall of the pharynx • Ⅳ： the cyst is deep to the carotid sheath abutting the pharynx, adjacent to the lateral pharyngeal wall.
Plain scan
• DWI
DWI
enhangcement
Final diagnosis
• branchial cleft cyst
Histology
• normal embryologic development, fourth week • the second branchial arch overgrows the third and fourth arches ; involute by seventh week • an arch fails to involute completely;an epitheliallined cyst.; may be identified in the early years; a second peak incidence in the second and third decades.
• The huge mass can result in breath and swallow deficits • 50% patient –fistula • Cancerization
The first branchial cleft cyst
• less than 8%，usually occur before 10 years old ， and in the left ，women：men=2:1 • through the parotid gland ,from meatus acusticus externus to submaxillary triangle . • communicate with the external auditory canal • associated with otorrhea and parotid gland cysts.
a oval mass locate in the inner side of left sternocleidomastoid ,heterogeneous hypodensity ，poor-defined，heterogeneous patchy enhancement,
• The mass has an irregular thickening cystic wall . cystic Schwannoglioma Enhancement CT