what are the indications for mri & ct: disc lesions post-operative spine(after surgery) tumors...
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What are the indications for MRI & CT:
Disc lesionsPost-operative spine(after surgery)
TumorsAny degenerative disease
TraumaCongenital abnormalities of the spine
• Preparations for CT & MRI:1-Fasting for 4-6 hours2-Contrast material Urographin ,telebrix 1-2 mg/kg
• Administration of contrast:Yes: In post-operative lumbar spine,
inflammatory disorders& neoplastic lesions.No: disc lesions, trauma.AnesthesiaUsed with children & uncooperative patients.
Patient position: Is usually supine, sometimes side lying, &
rarely prone. How to see: Scanogram: primitive picture to detect the
site of lumbar spine
Computed tomography (CT): . Usual scanning. . Axial slides 2-4 mm.
2 mm in cervical spine / 4 mm in lumbar spine Has bone & soft tissue window. CT screening:. Whole segment of the spine 5 mm in cervical spine, 8 mm in lumbar spine.. Selective Scanning Every 3 mm especially in trauma, also in cervical
disc lesions. N.B:If I want to see one vertebra e.g. L3 I have to take 1
vertebra above (L2 )& 1 below (L4).
CT Myelography:o Is considered as intrathecal contrast injection with
L- puncture needle.o We have 2 windows o Soft tissue & bone window.What are the structures I should evaluate in CT of
lumbar spine:• Lumbar spinal canal diameter normally 13 mm.• Disc lesions.• Others.
• facet, sacroiliac joints & paravertebral soft tissue.
Soft &bone window (CT) LumbarSoft &bone window (CT) Lumbar
1. Lumbar spinal canal diameter:Spinal canal is bony structure, so we see it in
bone window.The spinal canal must be closed (at the level of
pedicles).We measure the AP diameter. Types of canal stenosis:1-Relative:11-12 mm & this doesn’t need operation but it
needs operation if there’s disc. 2- Absolute: 8 -10 mm & it must be operated.
• Disc lesions:We detect it in soft tissue window.
Posterior border of the disc is more important as it has relation to the disc.
The normal posterior border of the disc is CONCAVE.
The abnormal is STRAIGHT OR CONVEX.
N.B:. Normally due to overload ,the disc of L5-
S1 is CONVEX & the abnormal is also convex, so to judge if it’s normal or no look at the next slide if: the posterior border of the disc is convex so it is ABNORMAL.
. The angle of inclination in L5-S1 is more than 30 & the device accept up till 30 only so part of the slide will contain bone & part will contain disc.
Normal CT Lumbar
Disc bulge(CT axial)
NERVE ROOTS
MRI – LUMBAR SPINEM
AXIAL VIEW
FORAMEN
Manifestations of arthritis in any joint: (Spondylosis in spine and osteoarthritis of
other joints)1.Osteophytic lipping.2.Narrow joint space.3.Subarticular bone sclerosis4.Sub cortical pseudo cystic changes.5.Intra articular air.(vaccum phenomena)
Vacuum phenomenaVacuum phenomena
CT of cervical spine
We have 2 types of joints:• Neurocentral joint:Is the articulation between one vertebra above &
one vertebra below which makes the shape of the body of the vertebral end plate .
• Facet joint:Is the articulation between the inferior lip of the
transverse process of one vertebra above with the superior lip of the transverse process of the vertebra below, it’s called Hamburger’s Sandwich.
Arthritis of the neurocentral or facet joint gives the same manifestations of nerve compression due to disc lesion.
Cervical disc in CT:• We see it in soft tissue window .The disc in cervical spine is very narrow so every
slide will contain both disc & bone, therefore there isn’t a slide of pure disc, So we choose the slide which contain more disc for assessment.
. All posterior edges of cervical spine are normally convex.
. See if there’s disc substance protruded than the bone.
. Normal spinal cord picture is kidney shaped.
Item Cervical Lumbar
Slide Width 2 mm 4mm
Neurocentral joint Present Absent
Spinal canal diameter
No diameters, but assessed by vision the spinal cord is kidney shaped & surrounded by C.S.F.
13 mm
Posterior edge of disc
Is usually convex All lumbar discs are concave except L5-S1 is normally convex or flat.
Difference between cervical & lumbar spine in CT
Stages of disc pathology (4 stages)
CT of the spine
CT axial bone& soft tissue widow
CT machine
MRI CT plain x-Ray
CT– CERVICAL SPINE
AXIAL SAGITTAL
C2-3 INTERVERTEBRAL DISC
DISC
FACET JOINTFACET JOINT
SPINOUS PROCESS
FORAMEN
FORAMEN
AXIAL SAGITTAL
CT- CERVICAL SPINEC-1 SECTION
ARCH OF C-1
DENS
BASE OF SKULL
MASTOID
DISC
SPINOUS PROCESS
CT- LUMBAR SPINEPOST MYELOGRAM
CT– CERVICAL SPINEC- 3 SECTION
AXIAL SAGITTAL
PEDICLE
PEDICLE
LAMINA
AXIAL SAGITTAL
CT-- CERVICAL SPINEC-2 SECTION
CT-- CERVICAL SPINEC-2 SECTION
C-2 SPINOUS PROCESS
C-2 BODY
DEGENERATED
C6-7
CT axial CT sagittal
PEDICLE PEDICLE
NERVE ROOTS
CT- LUMBAR SPINEPOST MYELOGRAM
Axial
Posterior arch #(CT)
Burst # (CT) axial
sagittal CT
CT axial section (base of the skull)
FORAMEN
CT- LUMBAR SPINEPOST MYELOGRAM
FORAMEN
CT of cervical spine(sagittal)
CT axial
CT of cervical spine (axial)
CT sagittal
CT sagittal tear drop # dislocation
Tear drop # dislocation(plain)
THECAL SAC
LAMINALAMINA
CT-LUMBAR SPINEPOST MYELOGRAM
FACET JOINTS
CT- LUMBAR SPINEPOST MYELOGRAM
PEDICLE PEDICLE
NERVE ROOTS
CT- LUMBAR SPINEPOST MYELOGRAM