Branchial Apparatus Derivatives

Front 1

Branchial Arch 1
Cartilage

Back 1

Meckel's Cartilage:
Mandible, Malleus, Incus, spheno-mandibular ligament.

Front 2

Branchial Arch 1
Muscle

Back 2

Muscle of mastication: Masseter, temporalis, lateral and medial pterygoids
mylohyloids, anterior belly of digastric, tensor tympani, tensor veli palatini, anterior 2/3 of tongue.

Front 3

Branchial Arch 1
Innervation

Back 3

CN V2 and V3

Front 4

Branchial Arch 1
Pathology

Back 4

Treacher Collins Syndrome:
mandibular hyperplasia, facial abnormalities

Front 5

Branchial Arch 1
Arteries

Back 5

Maxillary artery (branch of external carotid)

Front 6

Branchial Arch 2
Cartilage

Back 6

Reichert's cartilage:
Stapes, Styloid Process, lesser horn of hyoid bone, stylo-hyloid ligament

Front 7

Branchial Arch 2
Muscles

Back 7

Muscles of facial expression, stapedius, stylohyloid, and posterior belly of digastric

Front 8

Branchial Arch 2
Innervation:

Back 8

CN VII

Front 9

Branchial Arch 2
Arteries:

Back 9

Stapedial Artery, Hyoid Artery

Front 10

Branchial Arch 3
Cartilage:

Back 10

greater horn of hyoid

Front 11

Branchial Arch 3:
Muscles:

Back 11

Stylopharyngeus (think of which nerve its innervated by)

Front 12

Branchial Arch 3:
Innervation

Back 12

CN IX

Front 13

Branchial Arch 3:
Pathology

Back 13

congenital pharyngocutaneous fistula: persistance of cleft and pouch --> fistula between tonsillar area, cleft in lateral neck

Front 14

Branchial Arch 4-6
Cartilage

Back 14

thyroid, cricoid cartilage, arytenoids, corniculate,cuneiform

Front 15

Branchial Arch 4
Muscles

Back 15

most pharyngeal constrictors, cricothyroid, levator veli palatini

Front 16

Branchial Arch 6
Muscles

Back 16

all intrinsic muscles of larynx except cricothyroid

Front 17

Branchial Arch 4:
Innervation:

Back 17

CN X. superior laryngeal branch- swallowing

Front 18

Branchial Arch 6:
Innervation:

Back 18

CN X. recurrent laryngeal branch- speaking

Front 19

Branchial Arch 3 and 4 develop into:

Back 19

form posterior 1/3 of tongue

Front 20

Branchial cleft 1:

Back 20

external auditory meatus

Front 21

Branchial cleft 2-4 derivatives:

Back 21

make temporary cervical sinuses, which are then destroyed by proliferation of 2nd arch mesenchyme. if the cleft persists: branchial cleft cyst in lateral neck

Front 22

Branchial Pouch 1:

Back 22

middle ear, eustachian tube, mastoid air cells.
contribute to endoderm-lined structures.

Front 23

Branchial Pouch 2:

Back 23

epithelial lining of palatine tonsil

Front 24

Branchial Pouch 3:

Back 24

dorsal wings- inferior parathyroids
ventral wings- thymus.
these end up BELOW the 4th pouch structures

Front 25

Branchial Pouch 4:

Back 25

dorsal wings: superior parathyroids

Front 26

Branchial Pouch 3 and 4
Pathology:

Back 26

aberrant development of 3rd and 4th pouches lead to DiGeorge syndrome:
t-cell deficiency ( because of thymic aplasia) and hypocalcemia (because of failure of parathyroid to develop)

Front 27

MEN 2A:
multiple endocrine neoplasms:

Back 27

mutation of germline RET (neural crest cells)
adrenal medulla- pheochromocytoma
parathyroid tumor- 3rd and 4th branchial pouch
parafollicular cells (medullary thryoid cancer)- 4th and 5th branchial pouch.