Chapter 24 The Fetal Head And Brain Flashcards
(122 cards)
1
Q
What should be included in the correct level for an HC measurement?
A
*Falx cerebri
*Thalamus
*CSP
2
Q
Following an intracranial hemorrhage, a cyst is noted within the cerebrum that communicates with the lateral ventricle:
A
Porencephaly
3
Q
The condition in which the frontal horns are small and the occipital horns are enlarged is referred to as:
A
Colpocephaly
4
Q
_____would not be normally located within the midline of the fetal brain?
A
Lobes of thalamus
5
Q
What cerebral malformations is as a result of agenesis or hypoplasia of the cerebellar vermis?
A
DWM
6
Q
A cisterna magna that measure 15mm and a normal appearing cerebellum is most likely:
A
Mega cisterna magna
7
Q
The lack of sulci within the fetal cerebrum is a reliable indicator of:
A
Lissencephaly
8
Q
The sonographic finding of a fluid-filled cranium with absence of cerebral tissue is consistent with:
A
Hydranencephaly
8
Q
The most common cause of hydrocephalus in utero is:
A
Aqueductal stenosis
8
Q
What fetal suture is located within the frontal bone along the midline of the forehead?
A
Metopic suture
9
Q
Absence of the skull is:
A
Acrania
10
Q
What cerebral abnormality are atypical facial features most commonly associated with:
A
Holoprosencephaly
11
Q
A lemon-shaped skull is related to:
A
Arnold-chiari II malformation
12
Q
A cloverleaf-shaped skull is related to:
A
Thanatophoric dysplasia
13
Q
The band of tissue that allows communication between the right and left cerebral hemispheres is the:
A
Corpus callosum
14
Q
______would be the most likely fetal cranial findings with TORCH infections
A
Intracranial calcifications
15
Q
A strawberry-shaped skull is commonly associated with:
A
Trisomy 18
16
Q
The cisterna magna should not exceed ______in the trans-cerebellar plane
A
10mm
17
Q
The most accurate measurement for estimating gestational age is:
A
HC
18
Q
A normal shaped skull is termed:
A
Mesocephaly
19
Q
The structure located between the two lobes of the cerebellum is the:
A
Cerebellar vermis
20
Q
The fourth ventricle is located:
A
Anterior to the cerebellar vermis
21
Q
The third ventricle is located:
A
Between the two lobes of the thalamus
22
Q
______is a genetic disorder that includes craniosynostosis, midline facial hypoplasia, and syndactyly?
A
Apert Syndrome
23
The most severe form of holoprosencephaly is:
Alobar
24
The interhalamic adhesion (massa intermedia) passes through the:
Third ventricle
25
Enlargement of the frontal horns and narrowing of the occipital horns is termed:
Colpocephaly
26
The 'sunbursts" of the cerebral sulci is a sonographic findings of:
Agenesis of the corpus callosum
27
The anechoic midline brain structure located between the frontal horns of the lateral ventricles is the:
CSP
28
The development of fluid-filled cleft within the cerebral hemispheres is the:
Schizencephaly
29
The double fold of dura mater that divides the cerebral hemispheres is the:
Falx cerebri
30
What will also typically be absent with agenesis of the corpus callosum?
CSP
31
What is located on both sides of the midline?
Lateral ventricles
32
The choroid plexus cyst could be associated with an increased risk of:
Trisomy 18
33
With what structure does the posterior fossa cyst associated with DWM communicate?
Fourth ventricle
34
The MCA/umbilical artery resistive index is normally above?
1.0
35
When the fetus is starved for oxygen, redistribution of the blood to the vital organ, such as the brain occurs in order to spare it from damage is called:
Brain-sparing effect
36
______is a group of thin-walled, pressure-sensitive vessels located in the subependymal layer of the ventricles
Germinal matrix
37
_______are found within the choroid plexus and produce an increase in the production of CSF, which leads to ventriculomegaly
Choroid plexus papillomas
38
The most common location for a cephalocele is in the:
Occipital region
39
The most common location of spina bifida is within the:
Distal lumbosacral region
40
______are protrusions of intracranial contents through a defect in the skull
Cephaloceles
41
The abnormal enlargement of the ventricles within the brain is called:
Ventriculomegaly
42
The lateral ventricle is measured in the:
Transaxial plane at the level of the atrium
43
The cerebral hemispheres are linked in the midline by the:
Corpus callosum
44
The normal to medium sized skull is termed:
Mesocephalic
45
The paired lateral ventricles are located on:
Both sides of the falx cerebri within the cerebral hemispheres
46
The two lobes of the thalamus are located on both sides of the:
Third ventricle
47
The point at which the body, temporal horn and occipital horn meet is the:
Trigone (atrium of the lateral ventricle)
48
_____are responsible for the reabsorption of CSF into the venous system
Arachnoid Granulations (Arachnoid villi)
49
The BPD is obtained in the axial plane at the level of the:
*CSP
*Thalamus
*Falx cerebri
50
The OFD is obtained at the same level of the:
BPD and HC
51
_____is an elongated, narrow head shape
Dolichocephaly (Scaphocephaly)
52
_____head shape is one that is considered round or short and wide
Brachycephalic
53
A cephalic index of less than 75 denotes a:
Dolichocephalic shape
54
A cephalic index of more than 85 denotes a:
Brachiocephalic shape
55
There are three main types of holoprosencephaly
*Alobar
*Semilobar
*Lobar
56
Alobar holoprosencephaly can take on three basic shapes:
*Pancake
*Cup
*Ball
57
Arachnoid cysts will not communicate with the:
Ventricular system
58
_______occur when the embryonic neural tube fails to close
Neural tube defects
59
The normal lateral ventricle does not typically measure more than _______at the level of the atrium
10mm
60
_____is a thick band of white matter that provides communication between right and left halves of the brain
Corpus callosum
61
_____are specialized cells within the ventricular system responsible for CSF production
Choroid plexus
62
The third ventricle connects to the fourth ventricle inferiorly by means of a long tubelike structure called the:
Aqueduct of sylvius (cerebral aqueduct)
63
CSF moves from the lateral ventricles into the third ventricle through the:
Foramina of monro
64
The cerebellum is measured in the transverse plane at the same level as the
Cisterna magna and thalamus
65
______describes the echogenic choroid plexus, hanging limp and surrounded by CSF, within the dilated lateral ventricle cerebri
"Dangling choroid" sign
66
____is diagnosed when there is absence of the corpus callosum, CSP, 3rd ventricle, interhemispheric fissure and falx cerebri
Alobar holoprosencephaly
67
_____is a condition in which the orbits are fused and contain a single eye
Cyclopia
68
_____is a fleshy, tonguelike appendage that is typically located within the midline above the orbits in association with cyclopia and holoprosencephaly
Proboscis
69
_____is a spectrum of posterior fossa abnormalities that involve the cystic dilation of the cisterna magna and 4th ventricle
Dandy-walker complex
70
______is a bridge of tissue located within the midline of the brain that connects the two cerebral hemispheres
Corpus callosum
71
______is associated with the development of fluid-filled clefts within the cerebrum
Schizencephaly
72
_____is initially produced by the yolk sac, fetal gastrointestinal tract, and the fetal liver
Alpha-fetoprotein (AFP)
73
______combines the lab values of hCG, estriol and maternal serum alpha-fetoprotein (MSAFP)
Maternal serum screening (triple screen)
74
______is a group of cranial abnormalities associated with the neural tube defect spina bifida
Arnold-chiari II malformation
75
______is the abnormal lateral ventricle shaped in which there is a small frontal horn and enlarged occipital horn
Colpocephaly
76
_____is the structure that will form the central nervous system
Neural plate
77
Premature fusion of the cranium sutures is called :
Craniosynostosis
78
The skull consist of _____cranial bones
8
79
Spaces that exist between the forming fetal bones are referred to as:
Fontanelles "soft spots"
80
The anterior fontanel, when completely filled with bone is referred to as:
Bregma
81
The posterior fontanel is referred to as the:
Lambda
82
The brain can be divided into two main parts:
*The cerebrum
*Cerebellum
83
There are six cerebral lobes:
*Frontal lobe
*Two temporal lobes
*Two parietal lobes
*Occipital lobe
84
The innermost layer of the meninges is the:
Pia mater
85
The middle layer of the meninges is the:
Arachnoid membrane
86
The dense, outermost layer of the meninges is the:
Dura mater
87
The absence of all or part of the corpus callosum is referred to as:
Agenesis of the corpus callosum
88
The cavum septum pellucidum will appear as an:
Anechoic "box-shaped" structure in the axial scan plane
89
The cranial ventricles are lined by a membrane called the:
Ependyma
90
Lissencephaly literally means:
Smooth brain
91
_______is the absence of the cranial vault above the bony orbits
Acrania
92
_____is a double fold of dura mater located within midline of the brain:
Falx cerebri
93
______ is the opening in the base of the cranium through which the spinal cord travels
Foramen magnum
94
The cerebrum can be further divided into a right and left hemisphere by the:
Intrahemispheric fissure
95
The corpus callosum forms late in gestation, but should be completely intact between ________weeks
18-20
96
_______is a midline brain structure located in the anterior portion of the brain between the frontal horns of the lateral ventricles
Cavum septum pellucidum
97
_______is the largest cistern in the skull, located in the posterior portion of the skull
Cisterna magna
98
The _____is composed of four ventricles, whose primary function is to provide cushioning for the brain
Ventricular system
99
________ is a rare condition in which a cyst communicates with the ventricular system
Porencephaly
100
_______is a condition which there are no gyri within the cerebral cortex
Lissencephaly
101
______is a fatal condition in which the entire cerebrum is replaced by a large sac containing CSF
Hydranencephaly
102
Clinical findings of acrania/anencephaly
1. Elevated MSAFP
103
Clinical findings of vein of Galen aneurysm (neonatal)
1. Congestive heart failure
104
Clinical findings of cephaloceles
1. Possible elevation of MSAFP
105
Clinical findings of Arnold-chiari II malformation
1. Elevated MSAFP
106
Sonographic findings of ventriculomegaly
1. Atrium of the lateral ventricle measure > 10mm
2. Atrial measurement > 15mm is considered moderate to marked ventriculomegaly
3. “Dangling choroid” sign
4. Dolaron of any part of the ventricular system
107
Sonographic findings of hydroanencephaly
1. Fluid filled cranium
2. Absent or partial absence of the falx cerebri
3. Maintained brain stem, basal ganglia and perhaps the thalamus
4. No identifiable cerebral cortex
108
Sonographic findings of Mega cisterna magna
1. Enlargement of the cisterna magna >10mm in the anterior posterior dimension
2. Normal cerebellum and fourth ventricle
109
Sonographic findings of schizencephaly
1. Fluid-filled clefts within the cerebrum
2. Agenesis of the CSP and corpus callosum(50%)
3. Ventriculomegaly
110
Sonographic findings of porencephaly
1. Cystic mass that communicates with the lateral ventricle
2. Most often unilateral
111
Sonographic findings of Lissencephaly
1. Lack of sulci and gyri within the cerebrum
112
Sonographic findings of Acrania/Anencephaly
1. Absent cranial vault
2. Some cerebral tissue may be present
3. "Froglike" faces or bulging eyes
113
Sonographic findings of Arnold-chiari II malformation
1. Lemon-sign/shaped cranium
2. Banana sign/shaped cerebellum
3. Obliterated cisterna magna
4. Colpocephaly
5. Enlarged massa intermedia
6. Hydrocephalus
7. Open spinal defect
114
Sonographic findings of Aqueductal stenosis
1. Atrium of the lateral ventricle measures > 10mm
2. Atrial measurement >15mm is considered moderate to marked ventriculomegaly
3. Dangling choroid sign
4. Dilation of the lateral ventricles and the 3rd ventricle
115
Sonographic findings of Alobar holoprosencephaly
1. Horseshoe-shaped monoventricle
2. Fused echogenic thalami
3. Absence of the CSP interhemisperic fissure, falx cerebri, corpus callosum and 3rd ventricle
4. Normal cerebellum and brain stem
116
Sonographic findings of Dandy-walker malformation
1. Enlargement of the cisterna magna>10mm in the anteroposterior dimension
2. Communication of the enlarged cisterna magna with a dilated 4th ventricle
3. Agenesis or hypoplasia of the cerebellar
4. Varying degrees of ventriculomegaly
117
Sonographic findings of Agenesis of the corpus callosum and cavum septum pellucidum
1. Partial or complete absence of the corpus callosum and absence of the CSP (after 18 weeks)
2. "sunburst" sign radial arrangement of the sulci which produces a "spoke wheel" pattern
3. Colpocephaly-small frontal horns and enlarged occipital horns (teardrop-shaped) lateral ventricles
4. Elevated and dilated 3rd ventricle
118
Sonographic findings of a choroid plexus cyst
1. Anechoic, round, smooth-walled cyst located within the choroid plexus of the lateral ventricle
2. Measures more than 2mm
119
Sonographic findings of cephaloceles
1. Open cranial defect (typically posterior in location)
2. Small or obliterated cisterna magna
3. Complex or simple appearing mass protruding from the cranium
120
Sonographic findings of vein of Galen aneurysm
1. Anechoic mass within the midline of the brain that contains turbulent arterial and venous flow when interrogated with pulsed and color doppler
2. Fetal hydrops
3. Cardiomegaly (caused by cardiac overload)
