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Supplement your training program with case-based learning for residents, registrars, fellows, and more.
For Private Practices
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Prepare trainees to be on call for the emergency department with this specialized training series.
34 topics, 1 hr. 48 min. of video
Extradural Spine Lesions
7 m.Degenerative Spondylomyelopathy
3 m.Traumatic Lesions of the Spine
6 m.Subdural Hematoma of the Spine
2 m.Epidural Hematoma of the Spine
2 m.Post-operative Hematoma
4 m.Discitis-Osteomyelitis of the Spine
5 m.Discitis-Osteomyelitis with Epidural Phlegmon/Abscess
4 m.Tuberculous Spondylitis
5 m.Discitis-Osteomyelitis with Prevertebral Abscess
2 m.Discitis Osteomyelitis with Anterior Epidural Phlegmon
3 m.Epidural Abscess from Facet Joint Infectious Synovitis
4 m.Paraspinal Abscess with Epidural Extension
3 m.Summary of Extradural Neoplasms
4 m.Lumbar Spine Schwannoma Extending into the Neural Foramen
2 m.Primary Osseous Extradural Neoplasms
8 m.Osteochondroma of the Spine
3 m.Extradural Metastatic Disease
4 m.Chondrosarcoma of the Spine
4 m.Metastatic Disease vs. Multiple Myeloma
3 m.Malignant versus Benign Compression Fractures
7 m.Extramedullary Hematopoiesis of the Epidural Space
3 m.Paraspinal Extramedullary Hematopoiesis
2 m.Multifocal Epidural Extramedullary Hematopoiesis
4 m.Epidural Lipomatosis
3 m.Extradural Congenital Lesions
6 m.Epidermoid Cyst of the Thoracic Spine
3 m.Spinal Congenital Anomalies: Myelomeningoceles
6 m.Cervicothoracic Myelomeningocele
3 m.Recurrent Myelomeningocele and Cord Tethering After Repair
2 m.Diastematomyelia
3 m.Diastematomyelia
3 m.Chronic Inflammatory Demyelinating Polyradiculoneuropathy
3 m.Extradural Processes – Conclusion
3 m.0:00
This was a patient who had a curious MRI scan.
0:05
On the pre-gad T1-weighted scan, we noticed that there
0:09
was soft tissue in the anterior epidural
0:11
space adjacent to the L2 vertebra.
0:16
But in addition,
0:17
on the T1-weighted scan, behind the L5-S1 levels
0:22
we also saw soft tissue which extended
0:25
even to the sacral region.
0:28
And you'll notice along the posterior sacral S3
0:31
level, there was similar gray tissue here.
0:35
What are we looking at?
0:36
We're looking at the soft tissue posterior
0:38
to the vertebral body here.
0:39
We're looking at the tissue at the L5-S1 level,
0:44
as well as extending inferiorly.
0:47
And then we see a similar area lower down in the sacral
0:51
region. So this is spanning multiple levels.
0:53
Normally, I'd be concerned about this being a disc herniation
0:57
with some minimal epidural hematoma.
1:00
But in this case,
1:01
with it being more diffuse in the
1:04
lumbar level at multiple levels,
1:07
I have to consider a differential diagnosis.
1:10
Let's look at the post-gadolium enhanced
1:12
scan and see whether that helps us.
1:15
So here we find the pre-gad T1, and
1:19
the post-gad T1-weighted scan.
1:21
There's just a little bit of faint enhancement
1:24
of this tissue in the epidural space.
1:27
It's not very dramatic.
1:29
We have a CT scan also on the patient,
1:32
and that shows similar process in the thoracic
1:35
spine posteriorly. In this case,
1:38
I think it's most important to check the electronic
1:42
medical record for the scenario
1:45
in which the patient is in.
1:47
It happened that this case had acute myelogenous leukemia.
1:51
And given that history,
1:53
we would suggest that this most likely represents
1:56
leukemic infiltration with extraosseous extension, and/or the presence
2:04
of lymphoma. And in point of fact,
2:07
that is what was the final diagnosis on biopsy.
2:11
However, in a different scenario,
2:15
such as a myelodysplastic syndrome or
2:19
a patient who has severe anemia,
2:23
the differential diagnosis would include extramedullary
2:26
hematopoiesis. And in point of fact, despite the clinical history,
2:33
the chest CT was read as extramedullary hematopoiesis
2:38
and the lumbar spine MRI read as leukemia,
2:42
which led to the definitive biopsy showing that,
2:47
yay! The neuroradiologist won and the thoracic
2:51
radiologist was incorrect. So again,
2:54
a differential diagnosis including leukemia, lymphoma,
2:58
extramedullary hematopoiesis.
3:00
And in a different scenario,
3:01
you might even consider, in a patient with multiple
3:04
myeloma, plasmacytoma, for example.
Interactive Transcript
0:00
This was a patient who had a curious MRI scan.
0:05
On the pre-gad T1-weighted scan, we noticed that there
0:09
was soft tissue in the anterior epidural
0:11
space adjacent to the L2 vertebra.
0:16
But in addition,
0:17
on the T1-weighted scan, behind the L5-S1 levels
0:22
we also saw soft tissue which extended
0:25
even to the sacral region.
0:28
And you'll notice along the posterior sacral S3
0:31
level, there was similar gray tissue here.
0:35
What are we looking at?
0:36
We're looking at the soft tissue posterior
0:38
to the vertebral body here.
0:39
We're looking at the tissue at the L5-S1 level,
0:44
as well as extending inferiorly.
0:47
And then we see a similar area lower down in the sacral
0:51
region. So this is spanning multiple levels.
0:53
Normally, I'd be concerned about this being a disc herniation
0:57
with some minimal epidural hematoma.
1:00
But in this case,
1:01
with it being more diffuse in the
1:04
lumbar level at multiple levels,
1:07
I have to consider a differential diagnosis.
1:10
Let's look at the post-gadolium enhanced
1:12
scan and see whether that helps us.
1:15
So here we find the pre-gad T1, and
1:19
the post-gad T1-weighted scan.
1:21
There's just a little bit of faint enhancement
1:24
of this tissue in the epidural space.
1:27
It's not very dramatic.
1:29
We have a CT scan also on the patient,
1:32
and that shows similar process in the thoracic
1:35
spine posteriorly. In this case,
1:38
I think it's most important to check the electronic
1:42
medical record for the scenario
1:45
in which the patient is in.
1:47
It happened that this case had acute myelogenous leukemia.
1:51
And given that history,
1:53
we would suggest that this most likely represents
1:56
leukemic infiltration with extraosseous extension, and/or the presence
2:04
of lymphoma. And in point of fact,
2:07
that is what was the final diagnosis on biopsy.
2:11
However, in a different scenario,
2:15
such as a myelodysplastic syndrome or
2:19
a patient who has severe anemia,
2:23
the differential diagnosis would include extramedullary
2:26
hematopoiesis. And in point of fact, despite the clinical history,
2:33
the chest CT was read as extramedullary hematopoiesis
2:38
and the lumbar spine MRI read as leukemia,
2:42
which led to the definitive biopsy showing that,
2:47
yay! The neuroradiologist won and the thoracic
2:51
radiologist was incorrect. So again,
2:54
a differential diagnosis including leukemia, lymphoma,
2:58
extramedullary hematopoiesis.
3:00
And in a different scenario,
3:01
you might even consider, in a patient with multiple
3:04
myeloma, plasmacytoma, for example.
Report
Description
Faculty
David M Yousem, MD, MBA
Professor of Radiology, Vice Chairman and Associate Dean
Johns Hopkins University
Tags
Spine
Neuroradiology
Musculoskeletal (MSK)
Metabolic
MRI
CT
Acquired/Developmental
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