Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
169 Cards in this Set
- Front
- Back
Mesenchymal buds from the early _____ form & penetrate masses destined to become ____.
|
trachea, lungs
|
|
What structures are developed through multiple divisions & budding?
|
bronchi, bronchioles, alveolar ducts, and alveoli
|
|
Between what weeks do the normal number of bronchi form?
|
16- 20 weeks
|
|
After 24 weeks there is a progressive _____ of the ____ cells lining the air spaces.
|
flattening, epithelial
|
|
What is the shape of the thorax?
|
symmetrically bell shaped
|
|
What are the lateral margins of the thorax?
|
ribs
|
|
What are the superior margins of the thorax?
|
clavicles
|
|
The ____ is the inferior margin of the thorax.
|
diaphragm
|
|
The thorax is slightly smaller than the ____ ____.
|
abdominal cavity
|
|
A small chest size is caused by:
|
oligohydramnios
|
|
What does oligohydramnios cause?
|
pulmonary hypoplasia, & decrease in thoracic size
|
|
When should chest circumference measurements be taken?
|
when the chest size is felt to be abnormal
|
|
Where should the chest circumference measurement be taken?
|
at the level of the 4 chamber heart in trv
|
|
The heart circumference measures _____ of the thoracic circumference.
|
1/3
|
|
What is the formula for chest circumference?
|
CA - HA x 100 / CA
|
|
The central thorax is occupied by _____.
|
mediastinum
|
|
The base of the heart is _____ to the diaphragm.
|
horizontal
|
|
The lungs have a _____ echo texture.
|
homogeneous
|
|
The lungs have a similar echogenicity to the _____ in the 2nd trimester.
|
liver
|
|
The lungs are slightly more ____ in the third trimester.
|
more echogenic
|
|
The lungs lie ____ to the diaphragm and serve as the lateral borders of the ____.
|
superior, heart
|
|
T or F. Ultrasound cannot be used to assess lung maturity.
|
true
|
|
The fetal lung is more echogenic on the side up due to:
|
shadowing in the far field.
|
|
The muscle separating the thorax and the abdomen is:
|
diaphragm
|
|
The diaphragm is inferior to the ____ but superior to the ____.
|
heart, liver
|
|
When evaluating the diaphragm bilaterally, you exclude the _____ _____.
|
diaphragmatic hernia
|
|
What is the sonographic appearance of the diaphragm?
|
curvilinear area w/ decreased echogenicity
|
|
The ____ diaphragm is usually easier to image because of the strong ____ interface.
|
right, liver
|
|
The voice box is known as the:
|
larynx
|
|
What is the sonographic appearance of the larynx?
|
anechoic tubular structure seen in SAG cross section
|
|
The ____ is a soft organ w/ 2 lobes.
|
thymus
|
|
Where is the thymus located?
|
anterior to the ascending aorta, and posterior to the mediastinum
|
|
The thymus is ____ in children but ____ in size after puberty.
|
large, decreases
|
|
A normal thymus is the most frequent cause of a _____ _____.
|
widened mediastinum
|
|
The thymic lobes often differ significantly in ____, giving an impression of a ____.
|
size, mass
|
|
What is the primary function of the thymus?
|
maturation of t-lymphocytes
|
|
What does the thymus produce?
|
the hormone thymosin
|
|
What does thymosin do?
|
stimulates maturation of lymphocytes in other lymphatic organs
|
|
On US, the thymus can be seen as a ____ ____ like structure draped over the ____ vessels.
|
soft pancake-like, mediastinal
|
|
Prenatal ultrasound is helpful to diagnose ____ ____.
|
thymic cysts
|
|
The esophagus is difficult to visualize on US unless the fetus is ____ or has ____.
|
swallowing, stenosis
|
|
The thymus is ____ w/ tiny echogenic ____, which differentiate from the lungs.
|
homogeneous, foci
|
|
Where is the AP diameter of the thymus measured?
|
in the ML @ the sternum
|
|
Respiration results in the aspiration of ____ ____ into the ____.
|
amniotic fluid, lungs
|
|
When is fetal breathing more prominent?
|
in the 2nd and 3rd trimesters
|
|
The fetus may breathe in response to what 2 things?
|
maternal activities, substance ingestion
|
|
Sugar ingestion ____ fetal breathing responses, while smoking ____.
|
increases, decreases
|
|
Fetal breathing movements are evaluated from at least ____ seconds.
|
20
|
|
Color flow doppler is observed through the ____ ____.
|
fetal nostrils
|
|
Fluid in the lungs @ birth clears by what 3 routes?
|
mouth & nose, into pulmonary capillaries, and into the lymphatics & pulmonary vessels
|
|
What is the major reason why fetuses younger than 24 weeks GA are considered non-viable?
|
pulmonary immaturity
|
|
Primitive fetal lungs mature & become capable of functioning sometime after ____ weeks GA.
|
24
|
|
What must be identified when evaluating fetal heart?
|
fetal position & situs, cardiac axis, heart/thoracic ratio, m-mode, 4 chambers, great vessels,
|
|
The fetal heart has a ____ position in the fetal chest.
|
horizontal
|
|
The fetal diaphragm is situated relatively high due to:
|
large liver & un-inflated lungs
|
|
How is the identification of the normal 4 chambers achieved?
|
taken w/ the beam perpendicular to the septum of the valves
|
|
What is the angle of the cardiac axis?
|
45 degree angle
|
|
The apex of the heart should not exceed a ____ degree angle from the line drawn perpendicular to the fetal spine.
|
45 degree
|
|
The normal fetal heart rate is _____ BPM.
|
120-160
|
|
What does the 4-chamber anatomy demonstrate?
|
atria, ventricles, atrio-ventricular valves, papillary muscles, foramen ovale/septum primum, and intercardiac septae
|
|
What do the atrio-ventricular valves consist of?
|
tricuspid & mitral valves
|
|
Where does the foramen ovale flap open?
|
in the left atrium
|
|
The right & left atria are ____ in size.
|
equal
|
|
The ____ ____ is considered the communication between the right & left atria.
|
foramen ovale
|
|
The apex may appear thicker due to the _____ _____.
|
moderator band
|
|
The ____ ventricle may be larger than the ____ ventricle late in pregnancy.
|
right, left (by 20%)
|
|
Why would the right ventricle be larger than the left late in pregnancy?
|
because it pumps blood thru the ductus arteriosus to the aorta & placenta
|
|
What is seen in a standard 4 chamber view of the fetal heart that moves with heart beat?
|
echogenic focus left ventricle (echogenic papillary muscle or chordae tendinae)
|
|
The ____ muscles hold the valves in place.
|
papillary
|
|
Echogenic focus of the left ventricle affects ____% of the fetal population & is more common in _____.
|
5%, asians
|
|
The _____ _____ is a soft marker for down syndrome when seen with other markers.
|
echogenic papillary muscle/chordae tendinae
|
|
A band of muscles that crosses the apex of the right ventricle is the ____ ____.
|
moderator band
|
|
What is known as the anatomic landmark to identify the morphologic right ventricle?
|
moderator band
|
|
The ____ valve inserts lower/ closer to the apex than the ____ valve.
|
tricuspid, mitral
|
|
Both valves open during ____ and close during ____.
|
diastole, systole
|
|
What are the 2 great vessels of the fetal heart?
|
aorta, and pulmonary artery
|
|
What are the 2 types of outflow tracts?
|
LVOT (left ventricular outflow tract) & RVOT (right ventricular outflow tract)
|
|
The LVOT includes the ____ exiting the ____ ____.
|
aorta, left ventricle
|
|
The RVOT includes the ____ ____ exiting the ____ ____.
|
pulmonary artery, right ventricle
|
|
The RVOT bifurcates into the ____ ____.
|
pulmonary arteries
|
|
About ____ of structural malformations of the fetal heart can be R/O by imaging the 4 chamber heart & great vessels.
|
85%
|
|
Normal outflow tracts should ____ each other.
|
cross
|
|
The aorta exits the ____ ____ and forms the aortic arch.
|
left ventricle
|
|
The communication between main pulmonary artery & descending aorta is the ____ ____.
|
ductal arch
|
|
What is the "hockey stick" shape/sign?
|
ductal arch
|
|
Where does the IVC enter into the heart?
|
right atrium
|
|
The SVC enters the right atrium from ____ the heart.
|
above
|
|
Subcostal view can demonstrate continuity of the interventricular septum to the ____ ____.
|
aortic root
|
|
Where do the pulmonary veins enter?
|
left atrium
|
|
Optimal timing for fetal echocardiography is between ____ weeks GA.
|
18 - 22
|
|
The upper chambers are the ____ and are also known as the ____ chambers.
|
atria, filling
|
|
After birth there is no direct communication between the RT & LT ____.
|
atria
|
|
What is the right atrium connected to?
|
connected to the 2 great veins (SVC & IVC)
|
|
Oxygenated blood returns to the left atrium via 4 ____ ____.
|
pulmonary veins
|
|
From the left atrium, blood passes thru the ____ ____ into the ____ ____ & thru the ____ ____ into the ____ ____.
|
mitral valve, left ventricle, aortic valve, ascending aorta
|
|
The lower chambers are the ____ & are known as the ____ chambers.
|
ventricles, pumping
|
|
The pumping chambers pump blood _____ from the heart.
|
away
|
|
The lower chambers are connected to ____ ____ w/ ____ valves.
|
outflow tracts, semilunar
|
|
What do the LVOT/RVOT control?
|
The exit of blood from the heart
|
|
The RVOT involves the ____ ____.
|
pulmonary artery
|
|
The pulmonary exits the ____ ____ within the RVOT.
|
right ventricle
|
|
After the main pulmonary artery exits the right ventricle what does it bifurcate into?
|
Rt & Lt pulmonary arteries
|
|
The LVOT includes the ____ ____.
|
ascending aorta (or aortic root)
|
|
What does blood in the right atrium consist of?
|
a combo of oxygenated blood from the IVC & poorly oxygenated blood from the SVC
|
|
The ____ ____ acts as a one way valve allowing blood to pass from right to left only, between atria.
|
foramen ovale
|
|
What are the 3 shunts?
|
1st- ductus venosus
2nd- foramen ovale 3rd- ductus arteriosus |
|
Only _____% of blood circulates to the fetal lungs.
|
5 - 10%
|
|
T or F. Fetal lungs do not oxygenate blood.
|
True
|
|
Most pulmonary artery blood bypasses lungs & flows thru the ____ ____ to the arch.
|
ductus arteriosus
|
|
The pulmonary artery & aorta are connected by the ____ ____.
|
ductus arteriosus
|
|
Since fetal lungs are collapsed, only a small amount of blood circulates thru the ____ ____.
|
pulmonary capillaries
|
|
The ductus venosus becomes the ____ ____.
|
ligamentum venosum
|
|
The foramen ovale becomes the ____ ____.
|
foramen ovalis
|
|
The one way valve allowing blood to pass from Rt to Lt ventricle is:
|
foramen ovale
|
|
The ductus arteriosus becomes the ____ ____.
|
ligamentum arteriosum
|
|
What does the ductus arteriosus do?
|
shunts blood away from the lungs
|
|
What are the fetal cardiac structures no longer needed after birth?
|
foramen ovale, ductus arteriosus, ductus venosus, umbilical vessels
|
|
The ductus arteriosus usually constricts after birth. If the communication persists it's called:
|
patent ductus arteriosus
|
|
How does complete closure of the foramen ovale occur?
|
adhesion of the septum primum to the left margin of the septum secundum
|
|
The umbilical ____ constricts right after birth while the umbilical ____ can remain patent for some time s/p birth.
|
artery, vein
|
|
The optimal time for imaging cardiac structures is _____ weeks.
|
18 - 22 weeks
|
|
What is the most common cardiac defect?
|
atrial or ventricular septal defects
|
|
The left side of the heart perfuses the fetal _____.
|
cranium
|
|
The right side of the heart perfuses the _____ _____ of the fetus.
|
systemic circulation
|
|
Normal outflow tracts ____ eachother.
|
cross
|
|
The heart develops from the ____ ____.
|
splanchnic mesoderm
|
|
The endocardial tubes are situated _____ beneath the pharynx.
|
ventrolaterally
|
|
The endocardial tubes eventually fuse to form a single ____ ____ ____.
|
straight cardiac tube
|
|
The cardiac tube consists of what 2 layers?
|
endocardium & epicardium
|
|
What surrounds the cardiac tube layers?
|
the pericardial cavity
|
|
The primitive heart tube occurs at _____ days, after ovulation.
|
21-23
|
|
The heart tubes form 5 primitive areas longitudinally. What are they?
|
truncus arteriosus, bulbus cordis, ventricle, atrium, sinus venosus
|
|
The embryonic ____ veins empty into the ____ ____.
|
cardinal, sinus venosus (2 horns)
|
|
The right horn of the sinus venosus eventually leads to the ____ & ____.
|
IVC & SVC
|
|
The left horn of the sinus venosus leads to the ____ ____.
|
coronary sinus
|
|
The sinus venosus opens thru an ____ into the ____.
|
orifice, atrium
|
|
Between the atrium & the ventricle is a ____ ____.
|
atrioventricular canal
|
|
What is the most cephalic part of the heart tube?
|
truncus arteriosus
|
|
The truncus arteriosus connects the ____ thru the ____ ____ w/ the ____ ____.
|
ventricle, bulbus cordis, aortic root
|
|
The heart tube grows rapidly making an s-shape & it is called _____ _____.
|
cardiac looping
|
|
Rightward direction of looping is termed ____ ____.
|
dextro looping
|
|
Leftward direction of looping is called ____ ____ & is ____.
|
levo looping, abnormal
|
|
During normal looping, the atrial region is established by ____ ____ of the common ____.
|
transverse dilation, atrium
|
|
The ventricle if formed by the bent ____ ____ of the s-shaped tube & moves ____.
|
mid-portion, caudally
|
|
When does the heart start to beat?
|
@ 24 days GA
|
|
The ____ has a faster pulsation rate.
|
atrium
|
|
The origin of the cardiac pacemaker is the ____ ____.
|
right atrium
|
|
@ the 4th week of development ____ ____ of aortic arches form.
|
6 sets
|
|
Aortic arch 1 & 2 contribute to the _____ & _____ arteries.
|
Mandibular & maxillary
|
|
Aortic arch 3 leads to the ____ ____ ____ artery.
|
left common carotid
|
|
Aortic arch 4 goes two different ways. The left leads to the ____ ____ ____.
|
transverse aortic arch
|
|
The right part of aortic arch 4 leads to the ____ ____ artery & ____ ____.
|
left subclavian, brachiocephalic trunk
|
|
Aortic arch 6 forms the ____ ____ & right/left ____ arteries.
|
pulmonary trunk , pulmonary
|
|
The distal portion of the left 6th arch retains its connection & is known as the ____ ____.
|
ductus arteriosus
|
|
What does the ductus arteriosus connect?
|
The left pulmonary artery to the aortic arch
|
|
The IVS & EC eventually join, but early on has an opening called the ____ ____.
|
interventricular foramen
|
|
When does the interventricular foramen close?
|
When fetal length is 15-17 mm
|
|
The septum secondum fails to close leaving a large hole called the ____ ____.
|
foramen ovale
|
|
The septum spurium regresses & becomes the ____ ____.
|
crista terminalis
|
|
The ____ ____ cells initiate the septation process in the developing heart.
|
neural crest
|
|
The neural crest cells w/in the ____ ____ trigger the formation of the ____ ____ ____.
|
truncus arteriosus, aortico pulmonary septum
|
|
What does the aortico pulmonary septum do?
|
During looping it separates the root of the aorta from the pulmonary artery
|
|
The ____ of the ____ process divides the LVOT & RVOT from eachother.
|
septation, truncus
|
|
T or F. Septation & innervation of the heart occur simultaneously.
|
True
|
|
The ____ ____ leaflets attach to the ____ muscles thru the ____ _____.
|
atrioventricular valve, papillary, chordae tendinae
|
|
After septation of the truncus arteriosus & LVOT/RVOT, the ____ & ____ valves develop @ the roots of the ____ & ____ ____.
|
aortic, pulmonary
aorta, pulmonary artery |
|
What is a persistant truncus arteriosus defect?
|
a congenital anomaly w/ 1 great vessel & 1 large semilunar valve that can have 2-6 cusps
|
|
Infants w/ patent ductus arteriosus are given ____ to help close the ductus.
|
indocin
|
|
A patent foramen ovale causes ____.
|
cyanosis
|