Unit 4B

Front 1

Karyotype

Back 1

Compete set of chromosomes in a cell

Front 2

Euploid

Back 2

A normal balanced set of chromosomes (23)

Front 3

Aneuploid

Back 3

An unbalanced set of chromosomes

Front 4

Trisomy

Back 4

The presence of an extra chromosome

Front 5

Genetic disease may result from

Back 5

Abnormal number of chromosomes

Abnormal structure of one or more chromosomes

Single gene defect

Front 6

Single gene defect can be inherited as

Back 6

Autosomal dominate :a single defective gene inherited from one parent (50% likelihood of passing it on )

Or spontaneous mutation

Front 7

Autosomal recessive

Back 7

Due to a pair of defective genes

25% likelihood of passing the disorder

Front 8

Teratogenesis

Back 8

"monster"

Congenital malformations (anatomical or structural) present at birth

Front 9

Teratogenesis results from

Back 9

Genetic factor

Environmental factors

Multifactoral inheritance

Front 10

Teratogen

Back 10

Any substance causing abnormal structure in an embryo

Front 11

Sensitive period concept

Back 11

Certain structures are sensitive to specific teratogenic agents at given times and only at given times

An agent cannot influence the development of a structure if it occurs before or after that structure differentiates

Front 12

Physical agents

Back 12

Radiation: increases mental retardation, skeletal malformations and microcephaly

Heat: increases risk of NTD, IUGR, facial clefting and microcephaly

Front 13

Mechanical factors

Back 13

Uterine anomalies, oligohydramnios, amniotic bands

Front 14

Drug and Chemical agents

Back 14

Alcohol

Coumadin

DES

Thalidomide

Front 15

Fetal alcohol syndrome can cause

Back 15

IUGR, mental retardation, congenital heart disease, joint anomalies

Front 16

Coumadin can cause

Back 16

Anemceohaly, spinal bifida, congenital heart disease, growth retardation

Front 17

DES

Back 17

A synthetic estrogen hormone

--> causes T shaped uteruses in female offspring

Front 18

Thalidomide

Back 18

Europe 1950s

Used as a sleeping pill to treat morning sickness

Caused-congenital heart malformations, limb reduction, pyloric stenosis

Front 19

Maternal factors

Back 19

Infections

Diabetes

Sickle cell anemia

Front 20

3 types of neural tube defects (NTD)

Back 20

Anencephaly

Encephalocele

Spina bifida

Front 21

Anencephaly

Back 21

Babies born with anencephaly have underdeveloped brains and incomplete skulls. Most infants born with anencephaly do not survive more than a few hours after birth.

Front 22

Anencephaly appearance

Back 22

portions of mid brain Nd brain stem may be present

Bulging eyes, macroglossia and very short neck

Front 23

Anencephaly SONO findings

Back 23

fetal head should be seen by 12wks definitively by 15 wks major portions of cranium and intracaranial structures are absent polyhydraminos

Front 24

Encephalocele

Back 24

hole in the skull through which brain tissue protrudes

Front 25

Most common encephaloceles

Back 25

Occipital

Frontal and parental are also common

Front 26

Encephalocele sono appearance

Back 26

mass extending from calvarium- may be cystic or not

cranial distruption

cranial cavity appears small is a significant portion of brain is herniated

Front 27

Encephaloceles are associated with

Back 27

Hydrocephalus (80%)

Polyhydraminos

Spinal bifida (7-15%)

Front 28

Iniencephaly

Back 28

"star gazing" defect

A dramatic neural tube defect characterized by an exaggerated spinal lordosis, cervical rachischisis and an occipital encephalocele

Front 29

Iniencephaly sono appearance

Back 29

Exaggerated hyperextension of the fetal head Demonstration of cervical spina bifida

Front 30

Most frequently occurring permanently disabling birth defect

Back 30

Spina bifida - affecting 1/1000

Front 31

Rachischisis

Back 31

completely open spine with herniation and/or destruction of the spinal cord

Front 32

Spina bifida occulta

Back 32

failure of closure of vertebral column without any external abnormalities

Front 33

Spina bifida cystica

Back 33

failure of closure of vertebral column with external abnormalities

Front 34

Most common lotion Spina bifida occurs

Back 34

Lumbar

Front 35

Neural tube defects associated with

Back 35

Hydrocephalus

Encephalocele

Arnold Chiari II malformation

Front 36

Neural tube defects sono appearance (trv and sag)

Back 36

Spine ( transverse)- Splaying of the posterior ossification centers into a U or V shape A cystic structure may be seen extending from the back

Spine (sag)-Splaying of parrallel lateral ossification centers Soft tissure defect or discontiguity of skin and muscle

Front 37

Neurotube defects intracranial signs/appearance

Back 37

Lemon sign –flatting of frontal bones

Banana sign – dislocated cerebellium and obliteration of the cisterna magna

Chiari II malforamtion – variable displacement of the cerebellum, 4th ventricle and medulla oblongata through the foramen magnum

Front 38

Fetal head anatomy

Back 38

Thalamus, third ventricle, Cavum septum pellucidum – thalmus is diamond shape structure in center of brain, the third ventricle extends up as two small lines. The cavum septum pellucidum is anechoic structure also midline (usually more fluid than 3rd ventricle) forward of the thalmus

Front 39

Cisterns magna/cerebellum

Back 39

The cerebellum are two rounded half and have low to medium echoes with the cisterna magna seen posterior. It will be anechoic because of CSF can still see some of thalamus and cavum septum pallucidum

Front 40

4th ventricle located

Back 40

anterior to cerebellum