Embryological Development Disorders

Abstract

The external ear forms from the first two pharyngeal arches. The external auditory canal (EAC) develops from the first pharyngeal cleft. The middle ear and the inner layer of the tympanic membrane are derived from first pharyngeal pouch. Occur on a line from tragus to angle of the mandible. Excision for cosmesis and facial symmetry. Insufficient evidence to determine benefit of early ventilation tubes. Prenatal diagnosis is made with ultrasound. Velopharyngeal insufficiency (VPI) can occur in children with a repaired cleft palate, submucous cleft, post-adenoidectomy, or children without any obvious palatal abnormalities. Craniosynostosis is premature fusion of one or more skull sutures, which can be primary or secondary. Vascular tumours include infantile haemangiomas, congenital haemangiomas, tufted angiomas, kaposiform harmangiomas, pyogenic granulomas, etc. Most common tumour in Caucasian infants (10–12%), with female preponderance, mostly solitary, and two thirds are found in the head and neck region.