Training Collections
Musculoskeletal Imaging
Emergency Imaging
PET Imaging
Pediatric Imaging
Training Collections
Musculoskeletal Imaging
Emergency Imaging
PET Imaging
Pediatric Imaging
Lesson
Pre-Course Activities
1 topic, 3 min.
Lesson
Introduction to Stroke Imaging
4 topics, 17 min.
Lesson
Noncontrast CT
5 topics, 14 min.
Lesson
CTA Neck
10 topics, 33 min.
Vascular Imaging in Stroke - CTA vs MRA
2 m.Carotid and Vertebral Vasculopathies Overview & Examples of Atherosclerotic Disease
3 m.Case - Atheromatous Disease with Severe ICA Stenosis
4 m.Carotid & Vertebral Artery Dissection Overview & Examples
3 m.Case - Embolic Stroke with ICA Dissection
5 m.Collagen Vascular Diseases Overview - Examples of FMD, Carotid Web
2 m.Case - Fibromuscular Dysplasia (FMD)
5 m.Case - Ehlers Danlos
7 m.Inflammatory Conditions with Stroke Symptoms - Examples of Takayasu's, TIPIC
4 m.Case - Takayasu’s Arteritis
4 m.Lesson
CTA Head
9 topics, 37 min.
CTA Head in Acute Stroke - Source Images, MIPS, Collaterals
4 m.Case - MCA Stem Embolus with Good Collaterals
5 m.Case - MCA Stem Embolus with Poor Collaterals
4 m.Case - Basilar Tip Thrombus
6 m.Circle of Willis Stenoses: Differential Diagnoses
2 m.Case - Moya Moya disease
6 m.Case - Reversible Cerebral Vasoconstrictive Syndrome (RCVS)
5 m.Case - Primary Angiitis of the CNS (PACNS)
7 m.Infectious Causes of Multifocal Circle of Willis Stenosis
2 m.Lesson
CT Perfusion
3 topics, 15 min.
Lesson
MRI (DWI, FLAIR, SWI) of Acute Stroke
3 topics, 14 min.
Lesson
MRA of Head and Neck
6 topics, 18 min.
Lesson
Multifocal Strokes With No Visualized Vascular Abnormality
6 topics, 26 min.
Lesson
Brain Ischemia, Hypoxia, & Death
6 topics, 16 min.
Lesson
Stroke Mimics & Other Causes of Restricted Diffusion
7 topics, 18 min.
Stroke Mimics - Other Causes of Restricted Diffusion
2 m.Case - Seizure (Stroke Mimic)
4 m.Case - MELAS (Stroke Mimic)
3 m.Case - Hypoglycemia (Stroke Mimic)
3 m.Case - Herpes Virus Encephalitis (Stroke Mimic)
4 m.Case - Osmotic Demyelination Syndrome (Stroke Mimic)
3 m.Case - Brain Metastases (Stroke Mimic)
4 m.Lesson
MR Perfusion
8 topics, 17 min.
MR Perfusion - Data, Maps and Uses
4 m.Case - MR Perfusion Target Mismatch (Good Collaterals)
2 m.Case - MR Perfusion Target Mismatch (Poor Collaterals)
3 m.Case - Ischemia Detected Only on MR Perfusion (Case 1)
2 m.Case - Ischemia Detected Only on MR Perfusion (Case 2)
3 m.Arterial Spin Labelling Perfusion - Usage Examples
3 m.Case - ASL Matched Defect
2 m.Case - ASL Showing Tissue at Risk
2 m.Lesson
Subacute Stroke & Differentials
5 topics, 13 min.
0:00
I wanted to discuss a couple of other things
0:02
that cause diffuse multifocal narrowings
0:06
in the circle of Willis,
0:07
and one of them is varicella zoster.
0:09
It's seen in patients with decreased cell immunity,
0:13
so HIV organ transplant are very old,
0:16
like 90 year olds.
0:17
It's due to reactivation of the varicella zoster virus
0:21
due to a decrease in cell-mediated immunity.
0:24
Here at these are images of a 30-year-old female
0:26
with HIV, with acute left over extremity
0:29
weakness and facial numbness,
0:30
and she has a border zone infarct between
0:33
ACAs and MCAs,
0:34
and you can see on her coronal MIP image
0:38
that there are multifocal vascular stenosis
0:40
in the MCAs bilaterally,
0:42
and the bilateral ACAs.
0:45
Another cause of multifocal vascular narrowings
0:48
is tuberculosis meningitis.
0:50
You tend to see it in endemic areas,
0:53
especially in kids,
0:54
and what they have is basilar meningitis.
0:57
As you can see in this case,
0:58
this extensive thickening and enhancement
1:01
of the meninges,
1:03
along the basilar cisterns and extending
1:05
into the Sylvian fissures, and you can get
1:07
inflammation in the vessels and cause narrowing
1:10
of the bilateral MCAs and ACAs
1:12
and get multiple infarcts.
1:14
You can see the patient has multiple
1:15
MCA and ACA infarcts bilaterally.
Infectious Causes of Multifocal Circle of Willis Stenosis
HIDEInteractive Transcript
0:00
I wanted to discuss a couple of other things
0:02
that cause diffuse multifocal narrowings
0:06
in the circle of Willis,
0:07
and one of them is varicella zoster.
0:09
It's seen in patients with decreased cell immunity,
0:13
so HIV organ transplant are very old,
0:16
like 90 year olds.
0:17
It's due to reactivation of the varicella zoster virus
0:21
due to a decrease in cell-mediated immunity.
0:24
Here at these are images of a 30-year-old female
0:26
with HIV, with acute left over extremity
0:29
weakness and facial numbness,
0:30
and she has a border zone infarct between
0:33
ACAs and MCAs,
0:34
and you can see on her coronal MIP image
0:38
that there are multifocal vascular stenosis
0:40
in the MCAs bilaterally,
0:42
and the bilateral ACAs.
0:45
Another cause of multifocal vascular narrowings
0:48
is tuberculosis meningitis.
0:50
You tend to see it in endemic areas,
0:53
especially in kids,
0:54
and what they have is basilar meningitis.
0:57
As you can see in this case,
0:58
this extensive thickening and enhancement
1:01
of the meninges,
1:03
along the basilar cisterns and extending
1:05
into the Sylvian fissures, and you can get
1:07
inflammation in the vessels and cause narrowing
1:10
of the bilateral MCAs and ACAs
1:12
and get multiple infarcts.
1:14
You can see the patient has multiple
1:15
MCA and ACA infarcts bilaterally.
Report
Faculty
Pamela W Schaefer, MD, FACR
Professor of Radiology, Vice Chair of Education
Massachusetts General Hospital
Tags
Vascular Imaging
Neuroradiology
Neuro
MRI
Head and Neck
CTA
CT
Brain
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