1. Lecture
MRI Spine

2. Bone marrow changes: 1- Type I: edema 2- Type II: fatty ( white in T1)
3- Type III: bone sclerosis (like bone cortex black in T1 & T2)
Degenerative marrow changes:
If bony end plate is white in T1  fatty [as it 's not seen in T2]
If bony end plate is black  sclerosis

3. 1- Hypertrophy (developmental spinal canal stenosis) 2- calcification
1- Hypertrophy (developmental spinal canal stenosis)
2- calcification
3- ossification 
.Calcium deposition: is more seen in CT than in MRI as ca is black in both T1&T2
. Buckled ligamentum flava : I see if spinal canal is encroached or no.
. Ossification of posterior longitudinal ligament: OPL
N.B
Osteophytes has wide base against vertebra versus ossification has narrow base

4. 1- edema : due to compression by disc (ant) & ligamentum flava (post)
2- early myelomalacia : reversible if edema is treated
3- late myelomalacia : irreversible if edema isn't treated
N.B.
Both early & late myelomalacia produce focal area (white stain) of low signal in T1 & high signal in T2 so we differentiate by clinical pressure, by history & duration of illness
If it's recent edema
Not so far early myelomalacia
Far  late myelomalacia
If there is local lesion in spinal cord without compression another pathology

5. Paravertebral soft tissue shadows
.Hemorrhage, bone fragments
. Abcesses( inflammatory disorders)
.Tumor (neoplastic extra osseous mass)

6. Contrast administration ;DTPA
We use it to differentiate between postoperative scar tissue & residual or recurrent disc lesions
If it gains dye (becomes white in colour)  scar tissue
If it doesn't gain dye  disc lesion
If part gains dye & part doesn't gain  so there's both disc & scar tissue

7. Indications of contrast
1- To detect site of operation 2- To detect degree of thecal decompression 3- To detect post operative complications

8. N.B. Post operative cervical surgery:
There's no contrast administration in cervical spine as the aggressiveness of scar tissue formation in cervical spine is not as in lumbar spine after surgical interference.
N.B.
Contrast administration from 2 month to 20 years not after that as scar tissue becomes mature & contrast doesn't appear.

9. Types of surgery 1- spinolaminectomy 2-hemi laminectomy
(pore in the lamina & suction of the disc)
3-laminar fenestration minimally invasive ( the lamina of the above vertebra which is removed)

10. Post operative complications:
1- Scar tissue / disc lesions (scar tissue enhances)
2- Disc space infection
3- Arachnoiditis (adhesion between cauda equina nerve roots)
N.B.
Perineural scar: scar formation around roots which become compressed

11. Differential diagnosis between nerve root & recurrent disc:
After contrast administration if we see a black point on one side look at the contra lateral side
if there's also another black point so this is a nerve root
& if there's not present so this is recurrent disc
N.B.
Usually the nerve root at site of scar tissue is thick due to compression which leads to swelling

12. Arachnoiditis: It's diagnosed in axial T2 image never to be diagnosed in sagittal image As nerve roots are black & C.S.F. is white Pseudo cord sign: All nerve roots become adhesive to each other & appear as a cord in the cauda equine level (after L1-L2) Empty thecal sac sign: Nerve roots become attached at the edges of the thecal sac Disc space infection: Hyperemia, fluid, pus, edges of the vertebrae are filled with water In T2 appears white & in T1 appears black

13. Comparison between degenerated disc and disc space infection
. Disc is black in T1& T2
. Presence of osteophytes with bone marrow changes.
disc is white in T2 but black in T1
. sclerotic only