Module 8 Fetal brain and heart Flashcards
1
Q
The heart tube begins to develop from the mesoderm at which week and is fully formed by when?
A
Develops at the 5th week and is fully formed by the 10th week
2
Q
The heart tube is routinely valued from when to when?
A
From 18 weeks to term (40 weeks)
3
Q
When is the best time to evaluate the fetal heart?
A
18-24 weeks
4
Q
How does the heart sit in the chest? What is the heart position within the fetus in terms of midline? How is the apex angled? How much of the chest does it occupy? Which side is it on?
A
- Sits complete horizontal in the fetal chest
- Located to the left of midline
- The apex points about 45 degrees to the left
- Occupies 1/3 of the chest
- Located to the left of midline
5
Q
The two atria of the fetal heart lie how compared to the 2 ventricles ?
A
They sit posterior
6
Q
Which chamber of the fetal heart is the most posterior?
A
Left atrium
7
Q
Which chamber is the most anterior?
A
Right ventricle
8
Q
What are the valves of the fetal heart?
A
- Two atria ventricular valves
- Two semi lunar valves between the ventricles and circulatory system
9
Q
Where are the two atria ventricular valves located? What are they?
A
- Between the atria and ventricles
- Mitral and tricuspid
10
Q
Where are the two semi lunar valves located in the fetal heart?
A
Between the ventricles and circulatory system.
Consists of
1. Aortic valve and pulmonary valve
11
Q
What is the mitral valve also know as? How many cusps does it have? What does it do?
A
- Bicuspid valve
- Contains 2 cusps
- Passes blood from left atrium to the left ventricle
12
Q
How many cusps does the tricuspid valve have?
A
- 3 cusps
13
Q
What is blood flow in the tricuspid valve?
A
Passes blood from the right atrium to the right ventricle
14
Q
The mitral and tricuspid do what together? And how do they lay in terms of each other?
A
They open and close together and are situated at the same level in the heart
15
Q
The aortic valve contains how many cusps?
A
3 cusps
16
Q
What does the aortic valve do?
A
Passes oxygenated blood from the left ventricle into the aorta to be distributed to the rest of the body
17
Q
The pulmonary valve has how many cusps?
A
3
18
Q
What does the pulmonary valve do?
A
Passes deoxygenated blood (postnatal) from the right ventricle to the pulmonary artery to be oxygenated by the lungs
19
Q
How does the pulmonary artery sit in terms of position to the aorta?
A
It is more anterior and superior
20
Q
Which artery bifurcates?
A
Pulmonary artery
21
Q
What are the routine images of the heart? 5
A
- Four chamber heart
- Left outflow tract
- Right outflow tract
- Heart axis/ situs
- Fetal heart M mode
+/- cine clip
22
Q
At 19 weeks the fetal heart is the size similar to what?
A
An almond
23
Q
What does the fetal 4 chamber heart show?
A
All four chamber with septum
24
Q
What is the moderator band?
A
The thick muscle of the moderator band makes the right ventricular chamber look smaller than the left
25
The moderator band is used to prove what?
Which chamber is the right ventricle in abnormal hearts
26
What does the RVOT demonstrate?
The right ventricle with the pulmonary artery
27
Do the LVOT and RVOT cross each other in the fetal heart?
Yes
28
What is the normal fetal heart rate?
120-160
29
During first trimester what heart rate is concerning?
Under 100
30
In early pregnancies the heart may actually stop for how long?
A few seconds when you scan. IF this happens during a scan, move away and return to the heart at a later time.
31
What is the heart rate of the fetal heart during the third trimester?
Up to 180
32
What is Bradycardia in the 2nd and 3rd semester? What is tachycardia?
Under 100 is bradycardia and over 200 is tachycardia
33
When getting the cine clip of the fetus where should we start? And why? Where do we go from the start?
Start at the level of the AC to demonstrate the fetal stomach to confirm citrus. Then we slowly sweep cephalic on the fetus
34
What do we demonstrate during cine clips of the fetus? 5
1. Stomach
2. 4 chamber view
3. LVOT
4. RVOT
5. 3 vessel view
35
When getting a fetal heart M mode of the fetus, how many beats are usually measured?
1 beat
36
What comprises of the fetal circulation? 3
1. Ductus venous
2. Foramen ovale
3. Ductus arteriosis
37
What does the ductus arteriosis do?
Shunts blood from the pulmonary artery to the aortic arch to bypass the lungs during fetal life
38
What does the ductus arteriosis do after delivery ?
It closes
39
What is the fetal foramen ovale? What does it do?
1. Opening between atria
2. Brings blood from the right atrium to the left atrium
3. Helps bypass the lungs
40
The foramen ovale flap opens into what?
The left atrium
41
What are some additional images we can take for the fetal heart? 4
1. Short axis (circle and sausage)
2. SVC - IVC with the right atrium
3. Aortic arch
4. Pulmonary veins with the left atrium
42
What does the short axis view of the fetal heart demonstrate? 4
1. The right and left atria
2. The right ventricle
3. Pulmonary artery
4. Ductus arteriosis all circling the aorta
43
What does the IVC and the SVC do?
They bring deoxygenated blood back from the body to the right atrium
44
What are the three vessels at the aortic arch?
1. Brachiocephalic artery
2. Left common carotid artery
3. Left subclavian artery
45
What does the duct Ao arch look like?
A hockey stick
46
Where is the ductal arch?
Where the right ventricle with the ductus joins the aorta
47
What does the pulmonary veins do?
They bring oxygenated blood from the lungs to the left atrium in newborns
48
How many pulmonary veins are there?
4
49
On the ultrasound how many pulmonary veins will you see?
2 of them
50
The central nervous system (CMS) develops from what? And when?
A thickened area of the ectoderm in a process called neurulation at 4.5 LMP
51
During the formation of a neural plate, the neural tube closes where? And progresses where?
Starts around the middle and progresses to cranial and Cephalic ends
52
When does the cranial end and the caudal end of the neural tube close?
Cranial closes at 38 LMP and the caudal closes at 40 LMP
53
The neural tube differentiates into how many vesicles when?
It differentiates into three primary vesicles by the end of the 6th week
1. Prosencephalon
2. Mesencephalon
3. Rhombencephalon
54
What does the prosencephalon consist of?
The forebrain
55
What does the prosencephalon divide into? 2
1. Telencephalon
2. Diencephalon
56
What does the telencephalon consist of?
Cerebral hemispheres
57
What does the diencephalon consist of?
Thalamus and hypothalamus
58
What does the telencephalon: Cerebrum do?
Learned behaviour and personality
59
What does the cerebrum consist of? 5
1. Two frontal lobes: personality, voluntary motion
2. Two parietal lobes: Peripheral sensory
3. Two temporal lobes: Smell, taste and hearing
4. Two occipital lobes: vision
5. Two lobes called the insula: motor and sensory function organs
60
What is the diencephalon (thalamus)? What is it made up of?
1. It is made up of grey matter
2. Main relay center for sensory impulses from the right side of the body go through the thalamus to the left cerebral hemisphere
61
What is the mesencephalon? What does it consist of? What is the smallest portion of the brain? Where is it located?
1. Consist of mid brain
2. Smallest portion of the brain
3. Located anterior to aqueduct Sylvius
62
What does the mesencephalon create?
The cerebral peduncles
63
What does the rhombencephalon divide into? And what does it consist of? 2
Consist of the hindbrain and divides into the
1. Cerebellum and pons (Metencephalon)
2. Medulla oblongata (Melencephalon)
64
What does the pons connect? Where is it located?
1. Located between the midbrain and medulla oblongata
2. Connects the cerebrum to the cerebellum
65
What does the medulla oblongata do? Where did it extend from?
1. Extends from pons to the spinal cord
2. Regulates heart rate and respiratory rhythm and blood pressure
66
Where is the Rhombencephalon: cerebellum located? 2
1. Beneath the occipital lobes of the cerebrum in the posterior fossa.
2. Posterior to the pons and medulla oblongata
67
What are the two lateral hemispheres of the Rhombencephalon: cerebellum separated by?
Cerebella’s vermin’s and Falx cerebelli
68
What is the cerebella vermis function? What is its echogenicity?
The cerebella’s vermis is brightly echogenic and functions in the coordination of movement
69
What are the ventricles? What is it continuous with?
1. Four connecting cavities within the cerebral hemispheres and the brain stem
2. Continuous with the spinal cord cavity
70
All the cavities of the ventricles contain what?
CSF and choroid plexus
71
What is the ventricular system structure of the fetal brain? 7
1. Lateral ventricles
2. Foramen of Munro
3. 3rd ventricle
4. Aqueduct of Sylvius
5. 4th ventricle
6. Foramen of magendie
7. Spinal cord
72
The magendi is which aspect of the ventricles? What does it connect too?
1. Fourth aspect of the 4th ventricle
2. Connects the spinal cord
73
What is the luschka? What does it communicate with?
1. Lateral aspect of the 4th ventricle
2. Communicates with the menigies of the brain
74
The Luschka allows for CSF into what?
The subarachnoid space of the meninges
75
What are the largest of the ventricles?
Lateral ventricles
76
Where is the Lateral ventricles located?
In the cerebral hemispheres
77
Each of the lateral ventricles has what?
A body and three horns
78
What are the three horns of the lateral ventricles?
1. Anterior (frontal) horn
2. Posterior (occipital) horn
3. Inferior (temporal) horn
79
The junction of the body, occipital, and temporal horns forms what?
Trigone or atria of the ventricle
80
What does the 3rd ventricles look like? Where are they located? and What do they communicate with?
1. Thin
2. Located between the thalami and inferior to the corpus callosum
3. Communicates with the lateral ventricles via the foramen of Monro (interventricular foramen)
4. Communicates with the 4th ventricle via the aqueduct of sylvius (cerebral aqueduct)
81
Where is the 4th ventricle located? What is it anterior to?
1. Located within the brain stem
2. Anterior to the cerebellum
82
What is the 4th ventricle continuous with?
The central canal of the spinal cord via the foramen of magendie
83
What does the 4th ventricle communicate with laterally?
Subarachnoid space of the meninges vis the foramen of luschka
84
What does the choroid plexus do?
Produces CSF
85
Where is the choroid plexus located? Comparison to the 4th and 3rd ventricles?
1. In the body of the lateral ventricles
2. The roof of the 3rd ventricle
3. Superior side walls of the 4th ventricle
86
What is the corpus callosum?
A bridge of white matter nerve fibers that connect the right and left cerebral hemispheres
87
Where is the corpus callosum located?
Found deep in the longitudinal fissure
88
In what view do we see the corpus callosum in utero?3
1. Profile view
2. Midline sagittal
3. seen in neonates while scanning over the anterior fontanelle
89
What re the 4 parts from front to back of the corpus callosum?
1. Rostrum
2. Genu
3. Body
4. Splenium
90
What does the red arrows point towards?
The corpus callosum
91
What does the images point towards?
The top one is the Corpus callosum and the bottom one in the vermis
92
What happens if the corpus callosum is missing? Would the pericallosal artery be normal? What about the lateral ventricles? What would this do to the guru later in pregnancy?
1. CSP will not be visualized as it is absent
2. The pericallosal artery is abnormal
3. Lateral ventricles are teardrop shaped
4. Later in pregnancy the gyri appear in a sunburst pattern
93
What does this image tell us?
Normal corpus callosum
94
What does these images demonstrate?
Abnormal corpus callosums
95
What are the meninges? What does it surround?
1. Protective areas of the brain
2. Surrounds the brain, all the convolutions and grooves (gyri and sulci)
96
From inner to outer what are the layers of the meninges? 3
1. Pia matter
2. Arachnoid mater
3. Dura matter
97
What is the Cavum Septi Pellucidi? 2
1. Structure that separates the anterior horns of the lateral ventricles
2. Important landmark for BPD where the cranium is measured
98
Where is the Cavum Septi Pellucidi located in relation to the thalamus?
Anterior and slightly superior to the thalamus
99
What does the arrows point towards?
The left is the Cavum septi Pellucidi and the right is the fornix
100
Where is the cavum vergae found?
Found at the posterior tip of the septi pellucidi
101
Is the cavum vergae seen on prenatal ultrasounds?
No
102
When does the cavum vergae close?
Around 26 weeks
103
What does the sulci pattern allow? 2
1. More cerebral cortex, gray matter to develop
2. As well as increases the surface area of the brain
104
What is the Gyri?
Convolutions of the cerebral surface
105
What is the sulci?
Grooves in the cerebral hemisphers
106
Where is the cisterna magna located?
Between the cerebellum and the occipital bone
107
What does the cisterna magna contain?
CSF
108
Can the Cisterna magna be visualized in the normal fetus?
Yes
109
What does a fetus with spina bifida do to the cisterna magna?
Makes it absent
110
What is the normal measurements of the cisterna magna?
>1cm
111
Sometimes linear echoes can be seen within the cisterna magna? These are what?
These are the dura folds and they attach to the falx cerebelli. They are seen in the cisterna magna
112
What does this arrow point towards?
Cisterna magna
113
What is the falx cerebri?
A double layer of dura mater that separates the cerebral hemisphers
114
The falx cerebri runs within what?
The longitudinal fissure (Interhemispheric fissure)
115
What is the tentorium?
Dura mater that separates the occipital lobes of the cerebrum from the cerebellum
116
When is the tentorium best seen in neonates?
On neonatal cranial ultrasound studies
117
What is the circle of willis?
A cerebral ring of communicating arteries
118
The brain receives arterial blood from what two main pairs of vessels?
1. Internal carotid arteries
2. Vertebral arteries
119
What does each colour represent?
Red: LV
Pink: LA
Yellow: RV
Blue: Aov
120
What does each of the colors indicate?
Red: RA
Blue: RV
Pink: PA
121
What does this image demonstrate?
Pulmonary artery
122
What is this an image of?
Situs image of a baby that is Cephalic maternal right
123
What is this an image of?
Situs image of the stomach on the left and apex to the left
124
What is this an image of?
LVOT
125
What is this an image of?
Three chamber view
126
What does this image demonstrate?
How 3 vessel view should be measured
127
What does these two images represent?
Left: Normal heart beat
Right: Tachycardia
128
What does this image demonstrate?
Ductus arteriosis
129
What does each of these images demonstrate?
Ductus arteriosis
130
What does this image demonstrate?
Foramen ovale
131
What does this image demonstrate?
Ductal arch
132
What does the red arrow point towards?
Pulmonary veins
133
Label the image
Red: Prosencephalon
Blue: Mesencephalon
Purple: Rhombencephalon
134
What is this a measurement of?
Rhombencephalon
135
Label the structures
