imaging the spine Flashcards
What do x-rays show?
bone outlines
What does CT show?
bone outlines in more detail and some soft tissue structures e.g. lumbar discs
What does MRI show?
bone outlines in less detail but shows bone marrow, discs,ligaments and the spinal cords and nerves
What scans show bones
X-rays, CT,MRI
What scans show soft tissue
CT
especially MRI
What does a posterior arch comprise?
2 pedicles
2 laminae
1 spinous process
2 transverse process
Where does the neural foramen lie
inferir to the pedicle
C1 has no…
vertebral body
C2 has the
odontoid process
Ligaments ___ ligaments together and are responsible for spinal _____
tether
instability
ligaments are visible on X-ray T/F
F- they are not seen on X-ray or CT but seeing normal vertebral alignment on these tests implies intact ligaments and a stable spine
Ligaments are visible on MRI T/F
T
norma ligaments are black on MRI
Damaged ligaments are light on MRI
When is MRI used?
In patients with neurological defect which is not explained by x-ray or CT, to show soft tissue abnormality such as:
Acute prolapsed intervertebral disc
epidural haematoma
spinal cord damage
What features of bony tumours are seen on CT and X-ray findings
Bone destruction - owl winking
vertebral collapse
bone sclerosis
What features of bony tumours are seen on MRI findings?
early- bone marrow infiltration
late- extradural mass and spinal cord compression
Intervertebral discs cushion the vertebrae from ___
stress
Healthy discs are pliable and contain ___
water
discs dehydrate as a prelude to disease
X-rays are essential when there is a possibility of sciatica T/F
f
x-rays show disc space narrowing but this correlates poorly with symptoms of sciatica
What is sciatica?
Disc material may herniate through the disc lining the spinal canal
Herniated discs may press on spinal nerves
Nerve pressure produces sciatica
What scan is best when imaging the spinal cord
MRI- best way to show soft tissue disorders
invisible on x-rays and poorly shown on CT
What are the causes of spinal cord disease?
trauma
demyelination
tumour
ischaemia
