Table 1.
Summary of quantitative cartilage MRI
| Quantitative cartilage MRI | Associated cartilage contents | Interpretation |
|---|---|---|
| T2 mapping | Water, organization of collagen matrix | T2↑ = loss of collagen integrity |
| T1rho mapping | Proteoglycan (GAG), orientation of collagen fiber, concentration of other macromolecules | T1rho↑ = proteoglycan depletion |
| dGEMRIC | Proteoglycan (GAG) | T1↓ = proteoglycan depletion |
| Sodium imaging | Proteoglycan (GAG) | Na signal↓ = proteoglycan depletion, FCD↓ |
| DWI & DTI | Water molecules, collagen matrix, proteoglycans | ADC signal↑ = cartilage degeneration |
| uTE imaging | Water molecules, collagen matrix, proteoglycans | Useful for evaluation of calcified cartilage |
| gagCEST | Water and proteoglycan (GAG) | gagCEST value ↓= GAG depletion |
ADC, apparent diffusion coefficient; dGEMRIC, delayed gadolinium-enhanced MRI of cartilage; DTI, diffusion tensor imaging; DWI, diffusion-weighted imaging; FCD, fixed charged density; GAG, glycosaminoglycan; gagCEST, glycosaminoglycan specific chemical exchange saturation transfer; uTE, ultrashort TE.