herniations part 2, stenosis

Question 1

describe MRI of disc herniations

Answer 1

image hydrogen in high magnetic field
demonstrates morphology of sic with 3D imaging
shows nuclear signal intensity corresponding to degeneration

Question 2

what imaging procedure is considered the gold standard?

Answer 2

MRI

Question 3

what would you see on an MRI with a disc bulge?

Answer 3

focal bulge
obliterated epidural fat
deformed theca
displaced NR
decreased signal (MRI)

Question 4

what are the 6 ways a herniation can be described as?

Answer 4

central
lateral
foraminal
protrusion/bulge
extrusion/herniated
sequestration/free fragment

Question 5

disc bulge defintiion

Answer 5

circumfrential symmetric of the disc beyond the interspace

Question 6

disc protrusion definition

Answer 6

focal or asymmetric extension of the disc beyond the interspace, with the base against the disc of origin broader than any other dimension of the protrusion
incomplete disruption of the annulus

Question 7

disc extrusion definition

Answer 7

more extreme extension of disc beyond the interspace, with the base against the disc of origin narrower than the extruded portion
complete disruption of annulus

Question 8

disc sequestration definition

Answer 8

diameter of extruding material itself or with no connection between the material and the disc of origin

Question 9

is a bulge considered a herniation?

Answer 9

no

Question 10

what can bulge represent?

Answer 10

pathologic change, physiologic variant, or normal

Question 11

are there any direct findings with plain film for disc herniations?

Answer 11

no

Question 12

what are the indirect findings with plain films for disc herniations?

Answer 12

marginal osteophytes
reduced disc space
posterior subluxation
radiopaque ossicle in vertebral canal

Question 13

myelography of disc

Answer 13

injection of water based or oil based contrast into subarachnoid space

Question 14

what are the findings in a myelography of the disc?

Answer 14

indention of contrast column

amputation of root sleeves

Question 15

discography

Answer 15

injection of radiopaque contrast into nucleus pulposus to image morphology

Question 16

what will happen if a herniation is present during a discography?

Answer 16

contrast will leak into the spinal canal

provocative method for discogenic pain

Question 17

high intensity zone

Answer 17

area of high signal intensity on T2 weighted MRI of the disc, usually referring to the outer annulus
may reflect fissure or tear of annulus

Question 18

what is spinal stenosis?

Answer 18

narrowing of the spinal canal or IVF

Question 19

what are the types of spinal stenosis?

Answer 19

congenital (achondroplasia)

acquired (sponlyosis, spondylolisthesis, postsurgical, ligamentum flavum hypertrophy, IVD herniation)

Question 20

spinal canal parameters have three types based on what anatomy?

Answer 20

central (spinal canal)
neuroforaminal (lateral zone of IVF)
lateral recess (medial zone of IVF)

Question 21

cervical spine stenosis measurement

Answer 21

<12mm

Question 22

lumbar spine stenosis measurement

Answer 22

<15mm

Question 23

what are the anatomical parameters of sagittal canal?

Answer 23

anterior line- posterior vertebra

posterior line- spinolaminar line

Question 24

what can stenosis be from?

Answer 24

disc facet degeneration

herniation

Question 25

don’t confuse foraminal encroachment with what?

Answer 25

projectional distortion

Question 26

what are clinical signs of spinal stenosis in the cervicals?

Answer 26

long tract and radicular signs and symptoms

headaches, neck paain, +Lhermitte’s sign, mimics MS and ALS

Question 27

what are the clinical signs of spinal stenosis in the lumbars?

Answer 27

radicular signs and symptoms
back pain
neurogenic claudication