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Anatomy - BB Exam 3 > Embryo Blue Boxes > Flashcards

Flashcards in Embryo Blue Boxes Deck (39)
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1
Q

piriform sinus fistula

A

persistence of remnants of the ultimopharyngeal body along its path to the thyroid gland

2
Q

what are branchial vestiges?

A

cartilaginous or bony remnants of pharyngeal arch cartilages that appear under the skin in the side of the neck

3
Q

1st arch syndrome: in general, what is it and what causes it?

A

congenital anomalies of eyes, ears, mandable, and palate -caused by insufficient migration of neural crest cells into 1st arch during 4th week

4
Q

what are the two main manifestations of 1st arch syndrome?

A
  1. Treacher Collins syndrome

2. Pierre Robin sequence

5
Q

what is Treacher Collins syndrome?

A

mandibulofascial dysostosis, autosomal dominant:

  • malar hypoplasia
  • down slanting palpebral fissures
  • defects of lower eyelid
  • deformed external ears
  • some abnormalities of middle/internal ears
6
Q

what is the mutation associated with Treacher Collins syndrome?

A

mutation in TCOF1, which makes the protein treacle

7
Q

what is Pierre Robin syndrome?

A

autosomal recessive:

  • hypoplasia of mandible (micrognathia)
  • cleft palate
  • defects of eye, ear
8
Q

what is DiGeorge syndrome?

A
  • lack of thymus and parathyroid glands
  • defects in cardiac outflow tracts
  • lack of T cell fxn
  • low set ears
  • shortened philtrum of upper lip (fish mouth deformity)
9
Q

what causes DiGeorge syndrome?

A

3rd and 4th pharyngeal pouches fail to differentiate into thymus and parathyroid glands

10
Q

what is the most common metabolic disorder in neonates?

A

congenital hypothyroidism

11
Q

what is ankyloglossia?

A

short frenulum that extends to the tip of the tongue - interferes with its free protrusion, makes breast feeding difficult

12
Q

what is macroglossia?

A

excessively large tongue from hypertrophy of developing tongue - often seen in Down syndrome

13
Q

what is microglossia?

A

abnormally small tongue (rare) - usually associated with micrognathia and limb defects

14
Q

what is glossoschisis?

A

bifid or cleft tongue - incomplete fusion of lateral lingual swellings (uncommon)

15
Q

what is atresia of nasolacrimal duct?

A

when part of the nasolacrimal duct fails to canalize

16
Q

congenital auricular sinuses or cysts

A

located in a triangular area of skin anterior to auricle or external ear - minor anomaly

17
Q

what is congenital microstomia?

A

small mouth from excessive merging of mesenchymal masses in the maxillary and mandibular processes of the first pharyngeal arch

18
Q

what are oblique facial clefts?

A
  • extend from upper lip to medial margin of orbit
  • often bilateral
  • nasolacrimal ducts are open grooves
19
Q

what are lateral or transverse facial clefts?

A

-run from mouth toward ear

20
Q

what is macrostomia?

A

large mouth - results from bilateral facial clefts

21
Q

what is cyclopia?

A
  • single median eye enclosed in a single orbit

- usually have a tubular nose (proboscis) superior to eye

22
Q

what is synophthalmia?

A

fusion of eyes

23
Q

what is microphthalmia?

A

small eyes associated w/ other ocular defects

24
Q

severe vs. simple microphthalmos

A

severe -from arrested development of eye before or shortly after the optic vesicle has formed in 4th week

simple - development arrested in 8th week

25
Q

what is anophthalmia?

A

absence of an eye (unilateral or bilateral)

-eyelids form, but no eye present

26
Q

primary vs. secondary anophthalmos

A

primary: eye development arrested in 4th week, results from failure of optic vesicle to form
secondary: development of forebrain suppressed -> includes many other defects

27
Q

what determines iris color?

A

concentration and distribution of chromatophores in the loose vascular CT of iris

28
Q

what is congenital aniridia?

A

lack of iris tissue or almost complete absence of iris - from arrested development at rim of optic cup (mutation in Pax6)

29
Q

what is persistent pupillary membrane?

A

web-like strands of CT or vascular arcades over the pupil

-especially in premies

30
Q

what is congenital atresia of the pupil?

A

entire pupillary membrane persists - absence of opening of pupil

31
Q

what is congenital aphakia?

A

absence of the lens

32
Q

what is congenital cataracts?

A
  • opaque, grayish white lens
  • untreated = blindness
  • can be caused by rubella virus or congenital galactosemia
33
Q

what is cryptophthalmos?

A

congenital absence of the eyelids -> skin covers eyes

-autosomal recessive

34
Q

what are auricular appendages?

A

skin tags usually anterior to auricle - usually unilateral

-consist of skin

35
Q

what is anotia?

A

absence of the auricle - failure of mesenchymal proliferation

36
Q

what is microtia?

A

small or rudimentary auricle - from suppressed mesenchymal proliferation

37
Q

what causes atresia of the external acoustic meatus?

A

failure of the meatal plug to canalize

38
Q

what causes absence of external acoustic meatus?

A

failure of inward expansion of the 1st pharyngeal groove and failure of meatal plug to disappear

39
Q

what is congenital cholesteatoma?

A

fragment of keratinized epithelial cells “rest” that appears as a white cyst-like structure medial to and behind the tympanic membrane