Pharyngeal cleft, arch, and pouch

Question 1

CAP stands for

Answer 1

Cleft, Arch, Pouch (outside to inside)
C = eCtoderm
A = mesoderm + neural crest
P = endoderm

Question 2

1st cleft

Answer 2

• external auditory meatus

Question 3

2-4th cleft

Answer 3

• obliterated

Question 4

Persistent cervical sinus

Answer 4

• cleft cysts within lat neck, ant to SCM, immobile while swallowing

Question 5

1st arch- cartilage, muscles, nerves

Answer 5

Cartilage:

• Maxillary process (Maxilla, zygoMatic bone)
• Mandibular process (Meckel cartilage, Mandible)
• Malleus and incus, sphenoMandibular ligament

Muscles:

• Mastication (teMporalix, Masseter, lat and Medial pterygoids)
• Mylohyoid
• tensor tyMpani

Nerve:
CN V2 (maxillary), CN V3 (mandibular)

Question 6

2nd arch- cartilage, muscles, nerves

Answer 6

Cartilage:
- Reichert cartilage: Stapes, Styloid process, lesser horn of hyoid, Stylohyoid ligament

Muscles:
- Facial expression: Stapedius, Stylohyoid, platySma

Nerve:
- CN VII

Question 7

Pierre Robin sequence

Answer 7

micrognathia, glossoptosis (downward placement of tongue), cleft palate, airway obstruction

Question 8

Treacher Collins syndrome

Answer 8

• neural crest dysfunction (mandibular hypoplasia, facial abnormalities)

Question 9

3rd arch

Answer 9

Cartilage:
- greater horn of hyoid

Muscles
- styloPHARYNGEUS

Nerve:
- glossoPHARYNGEAL nerve- swallowing

Question 10

4th-6th arch

Answer 10

Cartilage:

• arytenoids
• cricoid + stuff
• thyroid

4th muscles: levator veli palatini, CRICOTHYROID (larynx), pharyngeal stuff (CNX- superior laryngeal branch) SWALLOW

6th muscles: larynx EXCEPT CRICOTHRYOID (CNX- recurrent laryngeal branch) SPEAK

Question 11

Pouches: Ear, tonsils, bottom-to-top

Answer 11

1. ear
2. tonsils
3. bottom-to: inf parathyroids, thymus
4. top: superior parathyroids
   (C cells of thryoid from ultimobranchial body/neural crest cells)

Question 12

Cleft lip:

Answer 12

failure of maxillary and medial nasal processes fuse (1 palate)

Question 13

Cleft palate:

Answer 13

failure of palatine shelves fusions (or with nasal septum) (2 palate)

Question 14

No MIF/Sertoli =

Answer 14

• male external

- both male/female internal