Cot death and the third branchial arch.

Congenital anomalies of the parathyroids in cases of cot death have been reported by several workers. Carotid-body hypoplasia also has been noted in typical cases of cot death. Neurally conditioned airway occlusion at the oropharyngeal level has been postulated as a precipitating factor of cot death. All these lines of evidence involve structures derived from the third branchial arch, and it is suggested that developmental arrest of this arch in early gestation may be the pathandemical basis of cot death.