Kiemenbogenzyste
Thyroglossal
duct pathology and mimics. Thyroglossal duct cyst and branchial cleft cyst. a Axial contrast-enhanced CT image shows a pathology proven thyroglossal duct cyst located anterior to the carotid vessels (arrowheads) and anteromedially to the sternocleidomastoid muscle (asterisks) with a tail-like extension medially to the hyoid bone (arrow). b Axial contrast-enhanced CT image demonstrates a second branchial cleft cyst (star) in a similar location within the right neck without hyoid extension
Imaging of
parotid anomalies in infants and children. First branchial-cleft cyst and fistulas. Right isolated intraparotid cyst on axial T2-weighted image (a). Type II anomaly, with an intraparotid cyst and 2 fistulas, the upper fistula running from the cyst to the external auditory canal [white arrow] and the lower running from the cyst to the skin, in Pochet’s triangle [red arrow] (b, c and d). Isolated fistula running from the parotid area to the skin (e). Congenital defect of the floor of the left external auditory canal (tympanal bone) on frontal and axial CT images (f and g)
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. This 18-day-old baby presented with intermittent stridor. On examination, a left-sided oropharyngeal swelling was identified. The baby had initially required continuous positive airway pressure. Microlaryngobronchoscopy identified an internal opening arising from the pyriform sinus apex (black arrow; image courtesy of Mr Y. Bajaj). Axial and coronal T1 with coronal STIR imaging identified a likely air-containing structure (thick white arrows) extending from the pyriform sinus to the level of the left thyroid gland that was abnormally small (thin white arrow). This was surgically confirmed to represent a fourth branchial cleft sinus tract
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. A sinogram performed on a child prior to surgical excision for a presumed first branchial cleft fistula. The opening within the right external auditory canal was cannulated and water-soluble contrast media injected confirmed the presence of a fistulous tract. During the procedure, contrast media was noted to pass via the tract through an external cutaneous opening in the right submandibular region
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. Transverse ultrasound (US) image from the same child as in Fig. 5, confirming the presence of a thick-walled cystic structure that was part of the sinus tract that extended to the left external auditory canal (white arrow)
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. MR imaging from a child presenting with purulent ear discharge. Axial and coronal T1 post-contrast (left hand images) with axial and coronal STIR images (right hand images) demonstrating a thick-walled sinus tract (white arrows) that extended to the clinically apparent opening in the left external auditory canal. The tract was surgically excised and confirmed to represent a first branchial cleft anomaly
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. Frontal schematic representation of a 5-mm human embryo at the fifth week of gestation. Sagittal sections taken through the branchial apparatus demonstrate the anatomic relationship of external clefts and internal pouches as well as the derivation of important head and neck structures. The sixth arch is very small and not visualised as a separate, discrete structure from pouch 4/5 in Fig. 1. [Reproduced with permission from Waldhausen J (2006) Branchial cleft and arch anomalies in children. Seminars in Pediatric Surgery 15:64–69]
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. Two-year-old child with axial fat-suppressed T1 post-contrast and sagittal short tau inversion recovery (STIR) images demonstrating a rounded and well-defined T1 isointense, T2 hyperintense lesion with thin peripheral enhancement (thick white arrows). It is located posterior to the right submandibular gland (thin white arrow) and anterior to the sternocleidomastoid muscle and carotid sheath (asterisk). This was confirmed to represent a second branchial cleft cyst following surgical excision
Branchial
cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings. T1 post-contrast and STIR images demonstrate a T2 hyperintense cystic mass with irregular peripheral enhancement after contrast administration. The abnormality was confirmed to be an infected second branchial cleft cyst in a 54-year-old man who had a history of recurrent infections at the mandibular angle
Branchial cleft anomalies comprise of a spectrum of congenital defects that occur in the head and neck.
Pathology
The anomalies result from branchial apparatus (six arches; five clefts), which are the embryologic precursors of the earand the muscles, blood vessels, bones, cartilage, and mucosallining of the face, neck, and pharynx .
During the 3 to 5 week of embryonic development, the second arch grows caudally and covers the third, fourth and sixth arches. When it fuses to the skin caudal to these arches, the cervical sinus is formed. Eventually, the edges of cervical sinus fuse and the ectoderm within the tube disappears . Persistence of branchial cleft or pouch results in a cervical anomaly located along the anterior border of the sternocleidomastoid muscle from the tragus of the ear to the clavicle .
The range of anomalies can include:
- cyst: no internal or external communication
- fistula: communicates both internally and externally
- sinus: incomplete tract
Cysts are the most common, outnumbering fistulas and sinuses ~2:1 . Among fistulae and sinuses, the order prevalence is thought to be: external draining sinus > complete fistula > internal draining sinus ; although some anomalies can occur in combination.
The full list of branchial anomalies includes:
- first branchial cleft anomalies (5-8%) : seen above the level of the mandible near the external auditory canal within or close to the parotid gland.
- first branchial cleft cyst
- first branchial cleft fistula
- first branchial cleft sinus
- second branchial cleft anomalies (commonest by far: 90-95%) : between the level of the mandible angle and the carotid bifurcation, deeper than the platysma and superficial layer of deep cervical fascia
- second branchial cleft cyst
- second branchial cleft fistula
- second branchial cleft sinus
- third branchial cleft anomalies (rare): infrahyoid neck
- third branchial cleft cyst
- third branchial cleft fistula
- third branchial cleft sinus
- fourth branchial cleft anomalies (rare): infrahyoid neck, usually adjacent to the thyroid gland
- fourth branchial cleft cyst
- fourth branchial cleft fistula
- fourth branchial cleft sinus
- the fifth cleft does not give rise to the cervical sinus of His which is part of the reason that there are no fifth branchial cleft anomalies
The 3 and 4 branchial arches tend to be very close and therefore the distinction between these two cleft anomalies can be difficult on imaging .
Differential diagnosis
- Paramedian thyroglossal duct cysts (usually branchial cleft cysts are well away from the midline)
- thyroid nodules and cysts
- necrotic lymph node metastases (e.g. from squamous cell and papillary thyroid carcinomas)
- infectious adenitis (e.g. tuberculosis)
- vascular lesion on non-enhanced CT images (e.g. mycotic aneurysm)
- lymphatic malformations
- neurogenic tumors with cystic degeneration (e.g. schwannomas)
- cervical dermoid cysts
Siehe auch:
- Mediastinum
- eingeschmolzene Lymphknotenmetastasen
- Schwannom
- zystische Lymphknoten
- Schilddrüse
- Neurofibrom
- Aortenbogen
- mykotisches (infiziertes) Aneurysma
- papilläres Schilddrüsenkarzinom
- zervikale bronchogene Zyste
- zystische Formation am Hals
- benignes Ganglioneurom
- Ductus thyreoglossus Zyste
- lymphoepitheliale Zyste der Glandula parotis
- tuberkulöse Halslymphknoten
- Halsfistel
- Zyste oder Fistel des zweiten Kiemenbogens
- Kiemenbogen
- zervikaler Abszess
- Zyste dorsal der Schilddrüse
- Zyste oder Fistel des vierten Kiemenbogens
- Zyste oder Fistel des ersten Kiemenbogens
- Zyste oder Fistel des dritten Kiemenbogens
und weiter:
Assoziationen und Differentialdiagnosen zu Kiemenbogenzyste:
Zyste oder
Fistel des zweiten Kiemenbogens
