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Weber State University
Radiologic Technology 4633
MRI of the Central Nervous System - Brain
Instructor: Rex T. Christensen MHA R.T. (R) (MR) (CT) (ARRT) CIIP
_____________________________________________
1. Pia Mater
2. Bridging veins
3. Arachnoid
4. Dura Mater
5. Subdural space
6. Subarachnoid space
2
1. Hypothalamus
2. Mammilary Body
3. Thalamus
4. Insula
5. Internal Capsule
6. Septum Pellucidum
7. Falx Cerebri
8. Cerebrum
9. Corpus Callosum
10. Lateral Ventricle
11. Caudate Nucleus
12. Putamen
13. Globus Pallidus
14. Third Ventricle
15. Optic Tract
3
1. Third Ventricle
2. Splenium of Corpus Callosum
3. Fourth Ventricle
4. Spinal Cord
5. Medulla Oblongata
6. Pons
7. Tongue
8. Clivus
9. Sphenoid Sinus
10. Cerebral Peduncles
11. Pituitary Gland
12. Frontal Sinus
13. Genu of Corpus Callosum
1. Corpus Callosum
2. Thalamus
3. Cerebellar Peduncle
4. Ethmoid Sinus
5. Frontal Sinus
6. Anterior Horn of Lateral Ventricle
7. Caudate Nucleus
8. Lateral Ventricle
4
1. Corpus Callosum
2. Septum Pellucidum
3. Optic Chiasm
4. Pituitary Gland
5. Sphenoid Sinus
6. Internal Carotid Artery
7. Caudate Nucleus
5
1. Posterior Horn of Lateral Ventricle
2. Fourth Ventricle
3. Medulla Oblongata
4. Cerebellum
5. Pineal Gland
6. Straight Sinus
1. Falx Cerebri
2. Occipital Lobe
3. Cerebellum
4. Cerebellar Tonsil
5. Cisterna Magna
6. Tentorium
6
Gray and White Matter
• Cerebral Cortex = The outer covering of
the cerebrum. It is often referred to as
gray matter.
• White matter is deeper in the brain, except
for the thalamus and some basal ganglia
(putamen, caudate nucleus) were given as
an example of "deep gray matter".
Gray and White Matter
1. Cerebral hemisphere (right side) 2. Gray matter. 3. White matter
Hearing loss, tinnitus, and dizziness are
symptoms of which of the following:
• A. glosspharyngeal neuroma
• B. trigeminal neuralgia
• C. pituitary adenoma
• D. acoustic neuroma
7
Hearing loss, tinnitus, and dizziness are
symptoms of which of the following:
• A. glosspharyngeal neuroma
• B. trigeminal neuralgia
• C. pituitary adenoma
• D. acoustic neuroma
ans: D
Which of the following is a condition in which
part of the Cerebellar tonsil is displaced
below the foramen magnum?
• A. Simmonds' disease
• B. Chiari malformation
• C. syringomyelia
• D. hydrocephalus
Which of the following is a condition in which
part of the Cerebellar tonsil is displaced
below the foramen magnum?
• A. Simmonds' disease
• B. Chiari malformation
• C. syringomyelia
• D. hydrocephalus
ans: B
8
All of the following techniques should be
employed EXCEPT __________ when
imaging the pituitary gland.
• A. increase in matrix (high resolution)
• B. fat saturation
• C. thin slices
• D. small field of view (FOV)
All of the following techniques should be
employed EXCEPT __________ when
imaging the pituitary gland.
• A. increase in matrix (high resolution)
• B. fat saturation
• C. thin slices
• D. small field of view (FOV)
ans: B
9
In order to visualize the internal auditory
canal, high resolution images are acquired
in which planes?
• A. sagittal and coronal
• B. sagittal and axial
• C. off axis oblique
• D. axial and coronal
In order to visualize the internal auditory
canal, high resolution images are acquired
in which planes?
• A. sagittal and coronal
• B. sagittal and axial
• C. off axis oblique
• D. axial and coronal
ans: D
In order to visualize the pituitary gland,
which planes are most useful?
• A. sagittal and coronal
• B. sagittal and axial
• C. off axis oblique
• D. axial and coronal
10
In order to visualize the pituitary gland,
which planes are most useful?
• A. sagittal and coronal
• B. sagittal and axial
• C. off axis oblique
• D. axial and coronal
ans: A
Intracranial Hemorrhage
5 stages based on the break down of
blood products:
1. Hyperacute (<12 h)
2. Acute (12 h to 2 days)
3. Early Subacute (2-7 days)
4. Late Subacute (8 days to 1 month)
5. Chronic (> 1 month to years)
11
Hyperacute Stage (<12 h)
Intracranial Hemorrhage is a liquid composed of 99% intracellular oxygenated hemoglobin.
The intracellular hemoglobin moves toward a deoxygenated state.
A heterogeneous clot develops that comprises blood cells, platelets, and protein-rich serum.
Acute Stage (12 h to 2 days)
Intracellular hemoglobin is progressively
deoxygenated.
Early Subacute Stage
(2-7 days)
Oxidative denaturation of hemoglobin
(deoxyhemoglobin)
Deoxyhemoglobin is gradually converted
to methemoglobin (heme of hemoglobin is
converted to ferric iron).
12
Late Subacute Stage
(8 days to 1 month)
Lysis of the red blood cells results in the
release of methemoglobin into the
extracellular space.
Chronic Stage
(> 1 month to years)
Macrophages and astroglial cells surround
and slowly phagocytise the hemotoma.
Extracellular methemoglobin is stored in
the macrophages and is converted to
hemosiderin and ferritin.
Hemorrhage CT vs. MRI
CT – Imaging characteristics of intracranial
hemorrhage are determined by the degree that
the x-rays are attenuated by the blood products.
Density of the hemorrhage is determined by the:
• Hematocrit
• Degree of blood clot retraction
• Hemoglobin content
13
Hemorrhage CT vs. MRI
CT – Imaging characteristics by stage:
Hyperacute – hyperdense (bright)
Acute – hyperdense (bright)
Early Subacute – hyperdense (bright)
Late Subacute – isodense (homogeneous)
Chronic – hypodense (dark)
Hemorrhage CT vs. MRI
MRI – Imaging characteristics of
intracranial hemorrhage are determined by
the:
• Paramagnetic effects of the break down
products of hemoglobin
• The magnetic field strength
• The pulse sequence.
Blood appearance by stage
14
Which of the following describes the reason it is very difficult to define gray/white matter structures on pediatric patients?
• A. pediatric patients lack water content
• B. pediatric patients must be sedated, sedation sometimes interferes
• C. pediatric patients are too uncooperative, image motion
• D. pediatric patients have a low development of myelin
Which of the following describes the reason it is very difficult to define gray/white matter structures on pediatric patients?
• A. pediatric patients lack water content
• B. pediatric patients must be sedated, sedation sometimes interferes
• C. pediatric patients are too uncooperative, image motion
• D. pediatric patients have a low development of myelin
ans: D
Which of the following tumors has these
characteristics on MR? 1. grows slowly 2.
originates from arachnoid tissue 3. is isointense
on T1-weighted images 4. usually the size of a
quarter 5. enhances with contrast injection.
• A. Neurofibroma
• B. Meningioma
• C. Astrocytoma
• D. Chiari malformation
15
Which of the following tumors has these characteristics on MR? 1. grows slowly 2. originates from arachnoid tissue 3. is isointense on T1-weighted images 4. usually the size of a quarter 5. enhances with contrast injection.
• A. Neurofibroma
• B. Meningioma
• C. Astrocytoma
• D. Chiari malformation
ans: B
With a history of seizures, the patient can be imaged using cardiac gating:
• A. to avoid taking talking to the patient throughout the study
• B. to make vessels appear black
• C. to monitor the patient for potential seizures
• D. to minimize pulsatile flow motion artifact in the temporal lobes
16
With a history of seizures, the patient can be
imaged using cardiac gating:
• A. to avoid taking talking to the patient
throughout the study
• B. to make vessels appear black
• C. to monitor the patient for potential seizures
• D. to minimize pulsatile flow motion artifact in the
temporal lobes
ans: D
When patients arrive at the imaging center with a cranial scar, the technologist must:
• A. ignore the scar
• B. cover the head with a sterile drape
• C. screen the patients, their doctor and/or family to find out what type of surgery they have had
• D. immediately perform the MRI scan to find out what surgery they underwent
When patients arrive at the imaging center with a
cranial scar, the technologist must:
• A. ignore the scar
• B. cover the head with a sterile drape
• C. screen the patients, their doctor and/or family
to find out what type of surgery they have had
• D. immediately perform the MRI scan to find out
what surgery they underwent
ans: C
17
When scanning patients to rule out brain
tumors, which of the following images is
acquired to evaluate the extent of the
lesion after injection of gadolinium?
• A. proton density
• B. gradient echo
• C. T2
• D. T1
When scanning patients to rule out brain tumors, which of the following images is acquired to evaluate the extent of the lesion after injection of gadolinium?
• A. proton density
• B. gradient echo
• C. T2
• D. T1
ans: D
The ACR (American College of Radiology) guidelines for brain imaging suggest that the minimum imaging procedure should include:
• A. Proton Density and T2 weighted coronal and axial images
• B. gradient echo imaging
• C. T1 weighted pre- and post-contrast enhancement axial images
• D. T1 weighted sagittal, proton density and T2 weighted axial images
18
The ACR (American College of Radiology) guidelines for brain imaging suggest that the minimum imaging procedure should include:
• A. Proton Density and T2 weighted coronal and axial images
• B. gradient echo imaging
• C. T1 weighted pre- and post-contrast enhancement axial images
• D. T1 weighted sagittal, proton density and T2 weighted axial images
ans: D
For most brain imaging procedures, which of
the following best describes the patient
position and centering landmark?
• A. supine/external auditory meatus
• B. none of the above
• C. supine/nasion
• D. prone/acantho-meatal line
For most brain imaging procedures, which of
the following best describes the patient
position and centering landmark?
• A. supine/external auditory meatus
• B. none of the above
• C. supine/nasion
• D. prone/acantho-meatal line
ans: C
19
Which of the following pathologies enhance
with the use of gadolinium? 1. metastatic
disease 2. active multiple sclerosis lesions
3. infectious disorders such as AIDS
• A. 2 and 3 only
• B. 1, 2, and 3
• C. 1 and 2 only
• D. 1 only
Which of the following pathologies enhance with the use of gadolinium? 1. metastatic disease 2. active multiple sclerosis lesions 3. infectious disorders such as AIDS
• A. 2 and 3 only
• B. 1, 2, and 3
• C. 1 and 2 only
• D. 1 only
ans: B
Which of the following should be of concern when using gadolinium enhancement while imaging the central nervous system?
• A. flow motion artifacts increase (are more prevalent)
• B. flow motion artifacts decrease (are less prevalent)
• C. a longer TR is required
• D. a longer TE is required
20
Which of the following should be of concern when using gadolinium enhancement while imaging the central nervous system?
• A. flow motion artifacts increase (are more prevalent)
• B. flow motion artifacts decrease (are less prevalent)
• C. a longer TR is required
• D. a longer TE is required
ans: A
On a non-contrast T1-weighted, spin echo
image, intracranial lesions such as MS
plaques will have which of the following
signal intensities?
• A. isointense to the brain
• B. increased
• C. decreased
• D. none of the above
On a non-contrast T1-weighted, spin echo image, intracranial lesions such as MS plaques will have which of the following signal intensities?
• A. isointense to the brain
• B. increased
• C. decreased
• D. none of the above
ans: C
21
Gadolinium enhances lesions associated
with disruption of the blood brain barrier
such as:
• A. abscesses
• B. gliomas
• C. metastasis
• D. All of the above
Gadolinium enhances lesions associated
with disruption of the blood brain barrier
such as:
• A. abscesses
• B. gliomas
• C. metastasis
• D. All of the above
ans: D
?
22
What type of image sequence would be
useful in demonstrating and characterizing
hyperintense lesions such as hemorrhage
or fat containing tumors?
• A. inversion recovery
• B. gradient echo
• C. T2-weighted spin echo
• D. T1-weighted spin echo
What type of image sequence would be useful in demonstrating and characterizing hyperintense lesions such as hemorrhage or fat containing tumors?
• A. inversion recovery
• B. gradient echo
• C. T2-weighted spin echo
• D. T1-weighted spin echo
ans: D
Which of the following are/is TRUE regarding periventricular hyperintense lesions (PVH)?
1. PVH lesions are non-specific findings seen with normal aging 2. PVH lesions can be seen with neurodegenerative processes such as Alzheimer's 3. PVH lesions can be seen with hydrocephalus
• A. 1 and 2 only
• B. 1, 2, and 3
• C. 2 and 3 only
• D. 1 only
23
Which of the following are/is TRUE regarding periventricular hyperintense lesions (PVH)?
1. PVH lesions are non-specific findings seen with normal aging 2. PVH lesions can be seen with neurodegenerative processes such as Alzheimer's 3. PVH lesions can be seen with hydrocephalus
• A. 1 and 2 only
• B. 1, 2, and 3
• C. 2 and 3 only
• D. 1 only
ans: B
Cerebrospinal fluid is produced by:
• A. corpus callosum
• B. ventricles
• C. choroid plexus
• D. the blood brain barrier
Cerebrospinal fluid is produced by:
• A. corpus callosum
• B. ventricles
• C. choroid plexus
• D. the blood brain barrier
ans: C
24
• Which of the following is a medium for
exchange of nutrients and waste products
between the blood and nervous tissue?
• A. cerebrospinal fluid
• B. venous system
• C. blood
• D. meninges
• Which of the following is a medium for
exchange of nutrients and waste products
between the blood and nervous tissue?
• A. cerebrospinal fluid
• B. venous system
• C. blood
• D. meninges
ans: A
25
Anatomy Learning Tools
http://www.meddean.luc.edu/lumen/MedEd/
GrossAnatomy/x_sec/mainx_sec.htm
http://www.med.wayne.edu/diagradiology/An
atomy_Modules/brain/brain.html
Questions?