1.2 - Embryology + Anamolies Flashcards Preview

ECU Craniofacial Anomalies + Laryngeal Rehab > 1.2 - Embryology + Anamolies > Flashcards

Flashcards in 1.2 - Embryology + Anamolies Deck (68):
1

What is an Embryo?

(2)

The first stage of development in utero

Between fertilization and 8 weeks

2

What is a Fetus?

How does it differ from an embryo? (2)

In utero - between 8 weeks gestation to birth

//

Organs begin functioning

Genitalia are visible on ultrasound

3

How large is an embryo at 4 weeks?

2.5 mm

4

What are Somites on an embryo?

(2)

Bilaterally paired blocks of mesoderm

Gives rise to the vertebrae, rib cage, and part of the occipital bone; skeletal muscle, cartilage, tendons, and skin (of the back).

5

How big is a fetus at 6 weeks?

8 mm

6

What are the 3 Germ Layers? on an embryo

Ectoderm

Mesoderm

Endoderm

7

What is the Ectoderm on an embryo?

(2)

Outer layer

Forms central nervous system, peripheral nervous system, + epidermis

8

What is the Mesoderm on an embryo?

(2)

Middle layer

Forms connective tissue, cartilage, bone, striated + smooth muscles, heart, blood + lymph vessels, kidneys, gonads, and other organs

9

What is the Endoderm on an embryo?

(2)

Inner layer

Forms epithelial lining of organs, parenchyma of the tonsils + other organs, epithelial lining of tympanic cavity, auditory tube, and other organs

10

What is the Neural Tube on an embryo?

(3)

Tube located in middle of embryo

Precursor to Central Nervous System

Rostral end will become brain

11

What structures can we see on an Embryo between 3-4 weeks?

(7)

Frontonasal Prominence

Heart

Umbilical Cord

Pharyngeal Arches 1 + 2

Mandibular Arch already formed

Lungs

Limb Buds

12

What is the Frontonasal Prominence of an embryo?

When does it appear?

Two areas of thickened ectoderm under the fore-brain, one on either side

///

3rd week

13

What is contained in the Frontonasal Prominence of an embryo?

(3)

Olfactory pits

Nasal pits (will become nostrils)

Upper lip

14

How do the nasal pits/nostrils form (Frontonasal Prominence) on an embryo?

When does it appear?

Fusion of median + lateral nasal prominences

4th week

15

How is the upper lip formed (Frontonasal Prominence) on an embryo? (2)

When does it appear?

Fusion of maxillary + median

Merging of median nasal

//

7th week

16

What is the Maxillary Processes on an embryo?

When does it appear

Embryological structure which gives rise to the upper jaw elements (e.g., maxillary bone) of the developing face

4th week

17

How is the Maxillary Processes formed on an embryo?

(3)

They enlarge and grow ventrally and medially, surrounding the future oral cavity.

Grow rapidly, first meeting the lateral nasal processes, and then the lower extension of the medial nasal processes.

The lower extension will give rise to the midstructure (philtrum) of the upper lip.

18

What are the Mandibular Process on an embryo? (2)

What are they the first to do?

When do they appear?

Forms the lateral wall and base of the primitive mouth

Give rise to the mandible and the lower part of the face and tongue.

//

First to merge with each other at the mid line

//

7th week

19

How do ears appear on an embryo?

Ears appear lateral + posteriorly as low set ears

20

What is the Hyoid Arch on an embryo?

When does it appear?

Almost complete ring of tissue around the external auditory meatus

4th week

21

What comes together to form the Hard Palate on an embryo?

(2)

Premaxillae

2 Palatine processes (vertical orientation)

22

Are the Oral and Nasal Cavities separated in a embryo at 7 weeks?

(2)

No

Tongue is in both cavities

23

What are the Pharyngeal Arches on an embryo?

When do they appear?

Series of externally visible anterior tissue bands lying under the early brain that give rise to the structures of the head and neck

4th week

24

What is the Mandibular Arch?

When does it form?

First of the bronchial arches

4th week

25

What happens if there is an interruption to fetal development during week 6?

Cleft lip (+/- palate) will remain

*****************

26

What forms the Nasal Prominence in an embryo?

Fusion of the maxillary prominence

27

What forms the Philtrum in an embryo?

Merging of median nasal prominence along with inferior movement

28

What is Fusion?

Two separate processes unite and become one

29

What is Merging?

Underlayers "push" up epithelium to "fill in" structures

(not a combining of two structures)

30

What important structure develops during the 9th week of fetal development?

How does this occur? (3)

Palate

//

Fusion of shelves (palatine processes)

Starts anteriorly to posterior

Last thing to fuse is uvula (bifid uvula)

31

What kind of growth spurt occurs during the 9th week of fetal development?

What happens? (4)

Mandibular

//

Oral cavity enlarges

Tongue drops down

Palatine processes go from vertically oriented to horizontally oriented

Palatine processes head towards the midline

32

When can cleft be detected via ultrasound?

Around 13 weeks

33

What can any interruption in embryological development cause?

(1 + 6)

Major or minor malformations of the...

- Ears

- Eyes

- Tongue

- Teeth

- Jaw

- Hands/feet

34

What will major or minor structural malformations correlate to?

(1 + 6)

Issues with...

- Speech

- Hearing

- Resonance

- Mastication

- Vision

- Swallowing

- Etc.

35

What are 6 anomalies that can affect the Ears?

Aural atresia/Auditory atresia

Microtia

Preauricular pits/preauricular tags

Otitus media

Otitus media with effusion

Oorrhea (drainage)

36

What is Aural Atresia/Auditory Atresia?

(3)

Congenital abnormality

Closure of external auditory canal.

EA canal and tympanic membrane may be small or fail to develop

37

What is Microtia?

(3)

Malformation of pinna

Greater deformity of outer ear

Increased likelihood of problems with middle ear or ossicles

38

What are Preauricular Pits/Preauricular Tags?

(2)

Projection of scalp or skin tags

From ear to cheek

39

What are 10 anomalies that can affect the Eyes?

Epibulbar dermoid

Epicanthal folds

Exophthalmos

Hypertelorism

Coloboma

Palpebral fissures

Ptosis

Myopia

Hyperopia

Strabismus

40

What is Epibulbar Dermoid?

Cyst on the retina

41

What are Epicanthal Folds?

Skin fold of the upper eyelid covering the inner corner of the eye

42

What is Exophthalmos?

(3)

Bulging of the eyes

Protrusion of 1 or both eyes

Beyond socket d/t congenital or pathological defect

43

What is Hypertelorism?

(2)

Excessive distance between 2 organs specifically the eyes

Typically presents as widely-set eyes

44

What is Coloboma?

(3)

Congenital defect of the eye

Notch of eyelid margins

Most often affects lower lid

45

What is Palpebral Fissures?

(2)

Opening between the eyelids

Narrow palpebral fissures = Velocardiofacial Syndrome (VCFS)

46

What is Ptosis?

Drooping or falling of the upper eyelid

47

What is Myopia?

Nearsightedness

48

What is Hyperopia?

Farsightedness

49

What is Strabismus?

(2)

Inability of 1 eye to attain binocular vision with other

Due to imbalance of the muscles of eye

(a.k.a., "lazy eye")

50

What are 5 anomalies that can affect the Tongue?

Microglossia

Macroglossia

Ankyloglossia

Glossopexy

Glossoptosis

51

What is Microglossia?

Small or absent tongue/genioglossus muscle

52

What is Macroglossia?

Enlarged tongue

53

What is Ankyloglossia?

(4)

Tongue tied

Short lingual frenulum

Anterior tongue attachment

Restricts movement of tongue tip

54

What is Glossopexy?

Tongue-lip adhesion

55

What is Glossoptosis?

(2)

Downward displacement or retraction of the tongue

Displacement of the tongue toward the pharynx

56

What are 3 anomalies that can affect the Jaw?

Micrognathia

Prognathia

Retrognathia

57

What is Micrognathia/Retrognathia?

What disorder is this commonly seen in?

Small or hypoplastic mandible

Pierre Robin Sequence

58

What is Prognathia?

Large or protrusive mandible

Caused by mandibular hyperplasia

59

What are 3 anomalies that can affect the Hands/Feet?

Polydactyly

Syndactyly

Brachydactyly

60

What is Polydactyly?

Extra fingers/toes

61

What is Syndactyly?

Fusion or webbing of digits

62

What is Brachydactyly?

Abnormally short digits

63

What are 5 anomalies that can affect the Cranium, Midface, and/or Palate?

Craniosynostosis

Microcephaly

Macrocephaly

Malar Hypoplasia

Cleft Palate

64

What is Microcephaly?

Small head circumference in comparison to age/sex matched peers

65

What is Macrocephaly?

Large head circumference in comparison to age/sex matched peers

66

What is Malar/Midface Hypoplasia?

(3)

Underdevelopment of the maxilla

In length (decreased midface height) or
depth (retrusion of the maxilla)

In the presence of normal mandible size,
midface retrusion may give the appearance of prognathism

67

What is Craniosynostosis?

(3)

Premature fusion of cranial sutures

Growth is restricted perpendicular to
the suture that is closed prematurely.

Requires craniotomy and skull reshaping

68

What syndromes are associated with Craniosynostosis?

(4)

Seathre-Chotzen Syndrome

Crouzon Syndrome

Apert Syndrome

Pfeiffer Syndrome