The Pharyngeal Apparatus -- Embryo

Question 1

Where are congenital auricular pits and cysts found?

Answer 1

Triangular area anterior to ear.

Question 2

What are congenital auricular pits/cysts?

Answer 2

Remnant of 1st phar. groove

Question 3

Cause of branchial/lateral cervical sinus?

Answer 3

Persistent 2nd groove/pouches

Question 4

Cause of a Branchial fistula?

Answer 4

Persistence of 2nd groove, ruptured closing plate

Question 5

What are branchial vestiges?

Answer 5

Cartilaginous/Bony remnants that fail to degenerate

Question 6

Describe 1st Arch Syndrome

Answer 6

Abnormal development of 1st arch derivatives

Question 7

Describe DiGeorge Syndrome

Answer 7

Failure of 3rd/4th pouches –> no thymus or parathyroid glands

Question 8

Cause of accessory thymic tissue?

Answer 8

Improper descent of thymus

Question 9

Cause of ectopic parathyroid glands?

Answer 9

IMproper migration or division of the original glands.

Question 10

Review other syndromes listed in the study notes.

Answer 10

Pretty please.

Question 11

Where may thyroglossal duct cysts become apparent?

Answer 11

Along the anterior neck or tongue.

Question 12

Concerns with a thyroglossal duct/cyst?

Answer 12

Nothing really unless they get infected.

Question 13

Where can an ectopic thyroid gland be found?

Answer 13

Along the course of the thyroglossal duct.

Question 14

What tissue type is the most common in ectopic thyroid?

Answer 14

Lingual thyroid tissue.

Question 15

What is thyroid hemiagenesis?

Answer 15

Unilateral failure of thyroid formation.

Question 16

More common abnormalities of the tongue?

Answer 16

Fissuring of the tongue and hypertrophy of the lingual papillae (down syndrome)

Question 17

Cause of congenital lingual cysts? So what?

Answer 17

Remnants of the thyroglossal duct. Can cause swilling, discomfort, dysphagia.

Question 18

What is ankyloglossia?

Answer 18

Frenulum goes to the end of the tongue (tongue-tied)

Question 19

Maxillary sinuses don’t grow until…

Answer 19

Teeth erupt in early adulthood.

Question 20

Prevalence of the frontal/sphenoidal sinuses at birth?

Answer 20

They don’t exist yet.

Question 21

Read Page 191-2

Answer 21

I’m not typing up that much cleft palate crap.

Question 22

Describe an oblique facial cleft.

Answer 22

Bilateral, upper lip to medial margin of orbit.

Caused by failure of mesenchymal masses to merge with lateral and medial nasal prominences.