Aortic Arch, Branchial Apparatus

Front 1

1st aortic arch

Back 1

Part of maxillary artery

Front 2

2nd aortic arch

Back 2

Stapedial artery
Hyoid artery

Front 3

3rd aortic arch

Back 3

Common carotid artery
Proximal part of internal carotid artery

Front 4

4th aortic arch

Back 4

Left: aortic arch
Right: proximal part of right subclavian

Front 5

6th aortic arch

Back 5

Proximal part of pulmonary arteries
Left only: ductus arteriosus

Front 6

1st cleft

Back 6

External auditory meatus

Front 7

2nd - 4th cleft

Back 7

Temporary cervical sinuses (obliterated by proliferation of 2nd arch mesenchyme)

Front 8

2nd - 4th cleft abnormality

Back 8

Persistent cervical sinus (branchial cleft cyst within lateral neck)

Front 9

1st arch cartilage

Back 9

Meckel's cartilage:
Mandible
Malleus
Incus
Spheno-mandibular ligament

Front 10

1st arch muscles

Back 10

Muscles of mastication:
Temporalis
Masseter
Lateral and medial pterygoids

Mylohyoid
Anterior belly of digastric
Tensor tympani
Tensor veli palatini

Front 11

1st arch nerves

Back 11

CN V2 and V3

Front 12

1st arch abnormality

Back 12

Treacher Collins syndrome:
1st arch neural crest fails to migrate
Mandibular hypoplasia, facial abnormalities

Front 13

2nd arch cartilage

Back 13

Reichert's cartilage:
Stapes
Styloid process
Lesser horn of hyoid
Stylohyoid ligament

Front 14

2nd arch muscles

Back 14

Muscles of facial expression
Stapedius
Stylohyoid
Posterior belly of digastric

Front 15

2nd arch nerves

Back 15

CN VII (facial expression)

Front 16

3rd arch cartilage

Back 16

Greater horn of hyoid

Front 17

3rd arch muscles

Back 17

Stylopharyngeus

Front 18

3rd arch nerves

Back 18

CN IX

Front 19

3rd arch abnormalities

Back 19

Congenital pharyngocutaneous fistula:
Persistence of cleft and pouch leads to fistula between tonsillar area, cleft in lateral neck

Front 20

4th - 6th arch cartilage

Back 20

Thyroid
Cricoid
Arytenoids
Corniculate
Cuneiform

Front 21

4th arch muscles

Back 21

Most pharyngeal constrictors
Cricothyroid
Levator veli palatini

Front 22

6th arch muscles

Back 22

All intrinsic muscles of larynx except cricothyroid

Front 23

4th arch nerves

Back 23

CN X (superior laryngeal branch)

Front 24

6th arch nerves

Back 24

CNX (recurrent laryngeal branch)

Front 25

5th arch cartilage

Back 25

No major developmental contributions

Front 26

5th arch muscles

Back 26

No major developmental contributions

Front 27

5th arch nerves

Back 27

No major developmental contributions

Front 28

1st pouch

Back 28

Middle ear cavity
Eustachian tube
Mastoid air cells

Front 29

2nd pouch

Back 29

Epithelial lining of palatine tonsil

Front 30

3rd pouch

Back 30

Dorsal wings: inferior parathyroids
Ventral wings: thymus

Front 31

4th pouch

Back 31

Dorsal wings: superior parathyroids
Ventral wings: parafollicular (C) cells of thyroid

Front 32

3rd and 4th pouch abnormalities

Back 32

DiGeorge syndrome:
T cell deficiency (thymic aplasia)
Hypocalcemia (failure of inferior parathyroid development)

Front 33

Endocrine neoplasia associated with branchial abnormalities

Back 33

MEN (multiple endocrine neoplasia) 2A

Adrenal medulla (pheochromocytoma)
Parathyroid TUMOR (3rd, 4th pouch)
Parafollicular cell CANCER (medullary THYROID cancer derived from neural crest cells associated with 4th, 5th pharyngeal pouches)

Front 34

Tongue origins

Back 34

Anterior 2/3: 1st arch
Posterior 1/3: 3rd, 4th arches

from OCCIPITAL myotomes

Front 35

Tongue motor innervation

Back 35

CN XII

Front 36

Tongue sensation

Back 36

Anterior 2/3: CN V3
Posterior 1/3: mainly CN IX; CN X (posterior)

Front 37

Tongue taste

Back 37

Anterior 2/3: CN VII
Posterior 1/3: mainly CN IX; CN X (posterior via SOLITARY NUCLEUS)