Advanced Spinal Imaging II

cons of routine imaging

costly, radiation exposure, may lead to unecessary procedures

rate of imaging referrals at IE

about 1/10

conditions where MRI is the preferred imaging modality

disc herniations, spinal neoplasm, spinal cord edema, myelomalacia, syringomyelia, edpidural hematoma

cause of spinal cord edema

abnormal connection between artery and vein causes the vein to become swollen

what does spinal cord edema look like on an MRI

more white in the spinal canal

difference between myelomalacia and syringomyelia on an MRI

there is a white bubble in the spinal cord

what is CT best used for

evaluation of bony

primary indications of CT scan

traumatic injuries, degenerative conditions, spinal alignment abnormalities, post-op, infectious disease, neoplastic, guidance for spinal interventions

where does the step off occur for a pars fracture

the level above the fracture

population most susceptible to pars fractures

older adults (degeneration), and adolescent athletes

why do you need to stop taking anti-psychotics and anticoagulants before a CT myelogram

contrast lowers the seizure threshold and increases bleeding risk

indication of a CT myelogram

compromised flow of neural and vascular structures (when MRI is contraindicated)

what does a CT myelogram look at

meninges, spinal cord, nerve roots, blood vessels

cost of CT vs MRI

CT is more expensive than MRI when combined with myelography

precautions following CT myelogram

monitor for side effects such as headaches, refrain from bending over and doing strenuous activities for 1-2 days

how does a discogram work

contrast is injected into a disc to increase the intradiscal pressure to recreate the pts pain

criteria for a positive discogram

7/10 or 70% pain and the adjacent disc is pain free

indication of discograms

localization of lesions to determine which level should be excised

normal findings on a CT discogram

marshmallows and cotton balls

contraindications for discography

bleeding disorders, anticoagulants, pregnancy, infection, contrast allergy, bony fusion, severe spinal stenosis

indication for CT angiography

when you are concerned about vascular involvement after a trauma

treatment of an artery occlusion in the cervical spine

give aspirin because of increased risk of stroke

how does a bone scintigraphy work

inject a radioactive substance that gets taken up by osteoblasts thus measuring bone metabolism/remodeling

clinical uses for bone scintigraphy

stress fractures, systemic bone disease (RA, osteopenia), vertebral compression fractures, ankylosing spondylitis

how to confirm a fracture suspected on bone scintigraphy

sagittal MRI to see the exact level

indication of bone scan with SPECT

for visualization of deep and specific areas especially when a spondy or lesion is suspected

DEXA t-score vs z-score

t-score compares to healthy adults and z-score compares to age and sex matched

t-score indicating osteopenia/osteoporosis

osteopenia: -1 to -2.5, osteoporosis: below -.25

populations recommended to get a DEXA

post menopausal women, men above 70 years

factors to related to a vertebral fracture

t-score less than -1, age above 70, greater than 4 cm height loss, greater than 5mg of prednisone