mr imaging of the brain - ucsdspinwarp.ucsd.edu/neuroweb/ppt/rad-401.pdf · mr imaging of the brain...
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Department of Radiology
University of California
San Diego
John R. Hesselink, M.D.
MR Imaging
of the Brain
MR System Components
Computer
Gradient Amplifier
Receiver
Transmitter
Digitizer
RF Coil
Gra
die
nt
RF Coil
Magnet
MR Imaging
Proton density
T1 relaxation time
T2 relaxation time
Flow effects
Source of Signal and Contrast
Spin-echo Pulse Sequence
Single Echo T1-weighted
RF
Signal
TR
TE
1st
echo
2nd
echo
Spin-echo Pulse Sequence Dual Echo T2-weighted
1st
echo
2nd
echo
RF
Signal
TR
TE
TE
T2-Weighted Images
Proton Density Weighted Images
Normal FLAIR Images
TR = 6000 msec, TI = 2000 msec, TE = 102 msec
T1-Weighted
Images
MR Signal of
Brain Lesions
Solid
Brain
Lesion PDW
T2W T1W
Cystic
Lesion
T2W
T1W
FLAIR
236
Subacute
Hemorrhage
PDW
T1W
T2W
Acute
Hemorrhage
T2W
FLAIR
T1W GRE
History: 9 y/o boy with prior head trauma
466
Hemorrhage Sequence Gradient-echo
PDW
Fat
or
Lipoma
T2W
T1W
MR Signal Intensities
T2WI PD/FLAIR T1WI
Solid mass Bright Bright Dark
Cyst Bright Dark Dark
Subacute blood Bright Bright Bright
Acute & chronic
blood Dark Dark Gray
Fat Dark Bright Bright
Acute Stroke Sequence Diffusion Weighted Imaging
MR Angiography
Dx: Anaplastic astrocytoma > GBM
MR Spectroscopy
Brain Screening Protocol
Sagittal T1-weighted images
Axial T2-weighted images
Axial FLAIR images
Diffusion-weighted images
Gradient-echo images
Axial T1-weighted images
Gadolinium: Axial & Coronal T1
History: 46 y.o. man
with headaches & increasing confusion
2 1
T2W PDW
{Page 2}
5
3 4
T1W
T1W / Gd
T1W
Dx: Meningioma & right MCA infarct
Increasing confusion {Page 3}
7 6
Student Cases
"May the FORCE be with you!"
History: 69 y/o man with nausea
& memory deficits for several weeks
413
Case 1
Dx: Glioblastoma
{Page 2}
History: 5 y/o girl with seizures
361
Case 2
{Page 2}
Dx: Amoebic abscesses
{Page 3}
History: 62 y.o. man with mumbling speech
26
2 1
Case 3
{Page 2}
3 4
Mumbling speech {Page 3}
5 6
Dx: Enhancing subacute infarct
{Page 4}
8 7
2 1
History: 48 y.o. male with a
sensorineural hearing loss
Case 4
Dx: Acoustic neuroma
{Page 2}
5
4
3
History: 48 y.o. man with
headaches & confusion
32
1 2
Case 5
{Page 2}
4 3
{Page 3}
7
6
5
Dx: Brain metastases -
Lung carcinoma
{Page 4}
10
9 8
History: 36 y.o. man with seizures
2 1
Case 6
History: Seizures
{Page 2}
5
4
3
Dx: AVM & basilar
tip aneurysm
{Page 3}
8
7
6
History: 62 y/o woman with headaches Case 7
Dx: Arachnoid cyst
{Page 2}
History: 27 y.o. man with
increasing confusion & lethargy
5
2 1
Case 8
Confusion and lethargy {Page 2}
3 4
Dx: Herpes simplex
encephalitis
{Page 3}
6
5
History: 72 y.o. woman
with headaches
49
3
2 1
Case 9
Dx: Parasagittal
meningioma
{Page 2}
5 4
6
History: 55 y/o female with motor
weakness, double vision, & emotional lability
272
Case 10
{Page 2}
Dx: Chronic multiple sclerosis;
Incidental sebaceous cyst
left posterior scalp
{Page 3}
History: 42 y/o female with chronic headaches
549
Case 11
{Page 2}
Dx: TB meningitis - HIV+
{Page 3}
History: 75 y.o. male
with dysmetria in upper extremities
1 2
Case 12
{Page 2}
3
5
4
Dx: Lipoma
{Page 3}
8
6
7
History: Young male with increasing
somnolence and irritability
11/20 -
2
1
3
Dx: Planum Meningioma
in a dog
4
{Page 2}
6
5
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