Modic type are signal intensity changes in vertebral body marrow adjacent to the endplates of degenerative discs.
Michael T. Modic, MD, wrote about these changes in the journal Radiology in 1988, and his name has been associated with these changes ever since.
Modic changes take 3 main forms:
Decreased signal on T1, and increased signal on T2.
Represents marrow edema.
Associated with an acute process.
Histological examination shows disruption and fissuring of the endplate and vascularized fibrous tissues within the adjacent marrowModic type 1 changes are hypointense on T1WI (A)
and hyperintense on T2WI (B).
Type II – the most common type
Increased signal on T1, and isointense or slightly hyperintense signal on T2.
Represents fatty degeneration of subchondral marrow.
Associated with a chronic process.
Histological examination shows endplate disruption with yellow marrow replacement in the adjacent vertebral body.
Type I changes convert to Type II changes with time, while Type II changes seem to remain stable.Modic type 2 changes are hyperintense on T1WI (A)
and isointense or hyperintense on T2WI (B).
Decreased signal on both T1 and T2.
Correlate with extensive bony sclerosis on plain radiographs.
Histological examination shows dense woven bone; hence, no marrow to produce MRI signal.Modic type 3 changes are hypointense on both T1WI(A) and T2WI (B).
MODIC CHANGES on MRI
|TYPE II||+||+/- (or slight)||fatty degeneration|
|TYPE III||-||-||bony sclerosos|