Chapter 22 - Imaging of the Spine

Question 1

Types of Modic changes on MRI

Answer 1

Modic type I: represents bone marrow edema and inflammation
T1: low signal
T2: high signal
T1 C+ (Gd): enhancement

Modic type II: represents normal red haemopoietic bone marrow conversion into yellow fatty marrow as a result of marrow ischemia
T1: high signal
T2: iso to high signal

Modic type III: represents subchondral bony sclerosis
T1: low signal
T2: low signal

Question 2

Lumbar spine: paracentral disc herniations affect the _________ nerve root while far lateral herniations affect the __________ nerve root

Answer 2

traversing; exiting

Question 3

isthmic spondylolisthesis

Answer 3

isthmic = there is a defect in the pars interarticularis

Question 4

degen spondylolisthesis

Answer 4

degenerative cause of the anterior slippage of one vertebra over another

Question 5

where are most disc herniations?

Answer 5

Posterolateral - the posterior longitudinal ligament is weakest here

Question 6

Characteristics of epidural abscess on MRI

Answer 6

rim enhancement on T2 images, isointense cord on T1 and a mass with tapered edges in the epidural space

Question 7

early changes on MRI for vertebral osteomyelitis

Answer 7

end plate erosion, loss of disc height

Question 8

characteristics of ligamentous injury post-trauma on MRI

Answer 8

T1 discontinuity/loss of normal signal, increased T2 signal in the same region

Question 9

DEXA score consistent with osteopenia

Answer 9

-1.0 to -2.5

Question 10

DEXA score consistent with osteoporosis

Answer 10

<-2.5

Question 11

Stenosis as measure on plain radiographs

Answer 11

relative stenosis: sagittal diameter <12mm
absolute stenosis: sagittal diameter <10mm