FIRST BRANCHIAL CLEFT ANOMALIES скачать в хорошем качестве

FIRST BRANCHIAL CLEFT ANOMALIES

Introduction First branchial cleft anomalies are rare congenital defects resulting from incomplete obliteration of the first branchial cleft during embryogenesis. These anomalies can present as cysts, sinuses, or fistulae near the external auditory canal (EAC), parotid gland, or cervical region. Classification Systems 1. Arnot Classification (1971): • Type 1: • Involves cysts or sinuses within the parotid gland, lined by squamous epithelium. • Appears in early or middle life. • Results from cell rests buried during the obliteration of the first branchial groove. • Type 2: • Found in the anterior cervical triangle, often communicating with the EAC. • Develops during childhood due to incomplete closure of the cleft. 2. Work Classification (1972): • Type 1: • Rare and purely ectodermal. • Duplication of membranous EAC, lined by squamous epithelium. • Presents as keratinizing cysts or sinuses posterior to the pinna or in the medial concha. • Tracts may extend to the bony plate of the EAC near the mesotympanum. • Type 2: • More common, involving ectodermal and mesodermal layers. • Duplication of membranous and cartilaginous EAC, presenting as cysts, sinuses, or fistulae. • Tracts often extend through the parotid gland toward the EAC. • May cross the facial nerve, with the lesions typically medial or lateral to it. Clinical Features • Recurrent swelling, discharge, or infection in the external ear or cervical area. • Type 1 lesions primarily affect the membranous EAC. • Type 2 lesions may involve the parotid gland and have a sinus or fistula near the upper neck. Diagnosis • High-resolution imaging like CT or MRI is essential to define the tract and its relation to the facial nerve. • Confirmatory histopathology helps differentiate these from other branchial anomalies. Management • Surgical excision is the definitive treatment. • Careful dissection is required to avoid injury to the facial nerve, especially in Type 2 lesions due to their proximity. • Recurrent infections necessitate complete tract removal. #nose #throathealth #ear #science #ent #nosebleed #otolaryngology