Congenital Lesions of the Face and Neck

Question 1

Development of the Face

• The external human face develops between the … and … week of embryonic development.
• Many opportunities for abnormal development
• Critical periods of development ​

Answer 1

• The external human face develops between the 4th and 6th week of embryonic development.
• Many opportunities for abnormal development
• Critical periods of development ​

Question 2

Development of the Face

• These developments take place in week … (left) and week … (right)

Answer 2

at 4 weeks and 5 weeks

Question 3

Development of the Face

• These developments take place in week … (left) and week … (right)

Answer 3

at 6 weeks and 7 weeks

Question 4

Development of the Face

• These developments take place in week … (left) and week … (right)

Answer 4

At 8 Weeks and 9 Weeks

Question 5

Electron Micrograph showing development of the …

Answer 5

face

Question 6

Basic Facial Structure

• 1 x f…
• 2 x …medial
• 2 x …lateral
• 2 x m….
• 2 x m…
• m… and m… 1st … arch
• m… arch

Answer 6

• 1 x frontonasal
• 2 x nasomedial
• 2 x nasolateral
• 2 x maxillary
• 2 x mandibular
• maxillary and mandibular 1st pharyngeal arch
• mandibular arch

Question 7

Formation of the Palate

• The maxillary process develops … processes
  
  • Should fuse to form … palate in midline
• Anteriorly, … palate formed
  
  • Part of that becomes … palate
• Any problem in formation of these and fusion of these - give rise to conditions of … …

Answer 7

• The maxillary process develops palatine processes
  
  • Should fuse to form hard palate in midline
• Anteriorly, primary palate formed
  
  • Part of that becomes soft palate
• Any problem in formation of these and fusion of these - give rise to conditions of cleft palate

Question 8

Electron Micrograph showing what happens during formation of the …

Answer 8

Palate

Question 9

Abnormalities in Development of Face

• A-C =
• D-E =

Answer 9

• A-C = cleft lip
• D-E = cleft palate

Question 10

The Pharyngeal Arches

• How many?
• What are they called?
• They all have m.., car…, n… and a branch of the … arch

Answer 10

• Mandibular, hyoid, third and fourth
• All have mesoderm, cartilage, a nerve, and a branch of the aortic arch

Question 11

The Pharyngeal Apparatus

Answer 11

Question 12

Pharyngeal Pouches - Embryology

Answer 12

Question 13

Pharyngeal Apparatus

Answer 13

Question 14

Embryology - Pharyngeal Apparatus

Answer 14

Question 15

Pharyngeal Arch 1 is the … arch

Answer 15

Pharyngeal Arch 1 is the Mandibular arch

Question 16

Pharyngeal Arch 1 - Mandibular

• Cranial nerve …
• Muscles of …
• What arises from it?

Answer 16

• Cranial nerve 5 - trigeminal
• Muscles of mastication
• Meckel’s cartilage, sphenomandibular ligament, malleus, incus

(From Teach me anatomy)

• the first pharyngeal arch is the largest and forms a dorsal maxillary process and a ventral mandibular process, which contains Meckel’s cartilage. It contributes to the development of the face and several facial bones as well as the temporal bone
  
  • cranial nerve: Cn Vc (Trigeminal)
  • mesodermal derivatives: tensor tympani, muscles of mastication, mylohyoid, anterior belly of digastric, tensor veli palatini
  • artery: first aortic arch (temporary)
  • neural crest cell derivatives: incus, malleus, anterior ligament of malleus, sphenoid spine, sphenomandibular ligament and the genial tubercle of the mandible

Question 17

Pharyngeal Arch 2 is …

Answer 17

Hyoid

Question 18

Pharyngeal Arch 2: Hyoid

• Cranial nerve …
• Muscles of …
• What arises from it?

Answer 18

• Cranial nerve - 7 (Facial)
• Muscles of facial expression
• Part body and lesser horn hyoid, stapes, styloid process, stylohoid ligament, thyroid cartilage, cricoid cartilage arise from it

(From Teach me anatomy)

• the second pharyngeal arch contains Reichert’s cartilage
• cranial nerve: CN VII (facial)
• mesodermal derivatives: stapedius, stylohyoid, muscles of facial expression, posterior belly of digastric
• artery: stapedial artery (temporary)
• neural crest cell derivatives: stapes, styloid process of the temporal bone, stylohyoid ligament, lesser horn and upper part of the body of the hyoid bone

Question 19

Derivates of First and Second Arches (Pharyngeal arches)

Answer 19

Question 20

Skeleton of Pharyngeal Arches 3 and 4

• Give rise to part body + greater horn … (3) and cartilages of the … (4)
• Supplied by cranial nerves … and …

Answer 20

• Give rise to part body + greater horn hyoid (3) and cartilages of the larynx (4)
• Supplied by cranial nerves 9 and 10 (glossopharyngeal and vagus)

Question 21

Muscles Pharyngeal Arches 3 and 4

• 3 = cranial nerve …, muscle = …
• 4 = cranial nerve …, muscle = …

Answer 21

• 3 = cranial nerve 9 (glossopharyngeal), muscle = stylopharyngeus
• 4 = cranial nerve 10 (vagus), muscle = pharyngeal muscles

Question 22

Embryonic Pharynx

Answer 22

Question 23

Pharyngeal Grooves and Pouches

• a number of outpocketings appear on the lateral wall of the pharynx – the pharyngeal pouches.
• The pouches separate the arches on the internal (…) surface whilst the clefts separate the arches on the external (…) surface.

Answer 23

• a number of outpocketings appear on the lateral wall of the pharynx – the pharyngeal pouches.
• The pouches separate the arches on the internal (endodermal) surface whilst the clefts separate the arches on the external (ectodermal) surface.

Question 24

Pharyngeal Grooves

Answer 24

• Note - thyroglossal duct
  
  • cyst or fistula after birth
  • While a baby is developing in the womb, the thyroid gland begins at the base of the tongue. Before birth the thyroid gland moves in the neck to its usual position below the thyroid cartilage and above the sternum. A portion of this path in which the thyroid gland moves may fill with mucus-like fluid, creating a thyroglossal duct cyst.

Question 25

Tongue and Thyroid Gland

Answer 25

Question 26

Electron micrograph of … and … gland

Answer 26

tongue and thyroid gland