A three-year-old boy with a swelling on the right side of his neck was
suspected of having a parapharyngeal abscess after clinical examinati
on and CT scan (computed tomography scan) of this region. Later it bec
ame clear, that the swelling was caused by an aneurysm of the internal
carotid artery. This case report describes the pitfalls and difficult
ies encountered in the diagnostic course and treatment planning.