pharyngeal embryology Flashcards
when do pharyngeal arches form?
4-5 weeks
what do the pharyngeal clefts do?
externally separate arches (ectoderm)
what do the pharyngeal pouches do?
internally separate arches (endoderm)
what cranial nerve innervates pharyngeal arch 1?
CN V3
trigeminal nerve mandibular branch
what are the skeletal components of pharyngeal arch 1?
maxilla
mandible
malleus
incus
what is the musculature of pharyngeal arch 1?
muscles of mastication
what cranial nerve innervates pharyngeal arch 2?
CN VII
facial nerve
what are the skeletal components of the pharyngeal arch 2?
stapes
lesser horn + upper hyoid
styloid
what is the musculature of pharyngeal arch 2?
muscles of facial expression
what cranial nerve innervates pharyngeal arch 3?
CN IX
glossopharyngeal
what are the skeletal components of pharyngeal arch 3?
greater horn + lower hyoid
what is the musculature of pharyngeal arch 3?
stylopharyngeus
what cranial nerve innervates pharyngeal arch 4/6?
CN X
vagus nerve
what are the skeletal components of pharyngeal arch 4/6?
laryngeal cartilage
what is the musculature of pharyngeal arch 4/6?
cricothyroid
intrinsic laryngeal
what is the pharyngeal cleft 1?
external auditory meatus
what is the pharyngeal cleft 2-4?
disappear
what is the pharyngeal pouch 1?
middle ear cavity + eustachian tube
what is the pharyngeal pouch 2?
palatine tonsil
what is the pharyngeal pouch 3?
thymus + inferior parathyroid gland
when do brachial cleft cysts form?
cleft doesn’t involute properly -> cyst forms
when do brachial cleft cysts present?
late childhood as painless swellings
