SUMMARY
Objective
To evaluate whether T2 and T1ρ relaxation times of knee cartilage determined with 3T magnetic resonance imaging (MRI) at baseline predict longitudinal progression of cartilage degenerative changes.
Methods
Quantitative analysis of cartilage was performed using 3T MRI with both T2 and T1ρ mapping techniques in 55 subjects without evidence of severe osteoarthritis (OA) [Kellgren–Lawrence (KL) score of 0–3] at baseline. Morphological abnormalities of cartilage, menisci, ligaments and bone marrow were analyzed on sagittal fat-saturated intermediate-weighted fast spin echo (FSE) sequences. Progression of degenerative changes was analyzed over a period of 2 years. Progression was detected in 27 subjects while in 28 subjects no changes were found. Differences between T2 and T1ρ relaxation times in these two cohorts were compared using one-way analysis of variance (ANOVA) and t tests.
Results
Baseline T2 and T1ρ values were significantly higher in the progression cohort in all compartments (P < 0.05) except the lateral tibia (LT) for T2 and the medial tibia (MT) for T1ρ. Progression of cartilage degenerative disease was most pronounced at the medial femoral condyles and at the femoro-patellar joint; differences between the two cohorts for T2 and T1ρ were also most significant in these compartments.
Conclusions
T2 and T1ρ measurements were significantly higher at baseline in individuals that showed progression of cartilage abnormalities over a period of 2 years and may therefore serve as potential predictors for progression of degenerative cartilage abnormalities in knee OA.
Background
There is an interplay between the intervertebral disc (IVD) and the adjacent bone marrow that may play a role in the development of IVD degeneration and might influence chronic lower back pain (CLBP).
Purpose
To apply novel quantitative MRI techniques to assess the relationship between vertebral bone marrow fat (BMF) and biochemical changes in the adjacent IVD.
Study Type
Prospective.
Subjects
Forty‐six subjects (26 female and 20 male) with a mean age of 47.3 ± 12.0 years.
Field Strength/Sequence
3 T MRI; a combined T1ρ and T2 mapping pulse sequence and a 3D spoiled gradient recalled sequence with six echoes and iterative decomposition of water and fat with echo asymmetry and least‐squares estimation (IDEAL) reconstruction algorithm.
Assessment
Using quantitative MRI, the vertebral BMF fraction was measured as well as the biochemical composition (proteoglycan and collagen content) of the IVD. Furthermore, clinical Pfirrmann grading, Oswestry disability index (ODI), and visual analog scale (VAS) was assessed.
Statistical Tests
Mixed random effects models accounting for multiple measurements per subject were used to assess the relationships between disc measurements and BMF.
Results
The relationships between BMF (mean) and T1ρ/T2 (mean and SD) were significant, with P < 0.05. Significant associations (P < 0.001) were found between clinical scores (Pfirrmann, ODI, and VAS) with T1ρ/T2 (mean and SD). BMF mean was significantly related to ODI (P = 0.037) and VAS (P = 0.043), but not with Pfirrmann (P = 0.451). In contrast, BMF SD was significantly related to Pfirrmann (P = 0.000) but not to ODI (P = 0.064) and VAS (P = 0.13).
Data Conclusion
Our study demonstrates significant associations between BMF and biochemical changes in the adjacent IVD, both assessed by quantitative MRI; this may suggest that the conversion of hematopoietic bone marrow to fatty bone marrow impairs the supply of available nutrients to cells in the IVD and may thereby accelerate disc degeneration.
Level of Evidence: 2
Technical Efficacy Stage: 3
J. Magn. Reson. Imaging 2019;50:1219–1226.
A significant decrease in PHLAT T1ρ/T2 signal by 2-years suggests potential tissue recovery after ACL-injury. Elevated T1ρ/T2 signal in the PHMED of injured knees at 2-years correlating with knee cartilage T1ρ/T2 signal elevations suggests involvement of the PHMED in subacute cartilage degeneration after ACL-injury and reconstruction.
finding showed osteophytes in 30 (93.8%), cartilage calcification in 24 (75%) (Double / triple contour sign in 5 (15.6%)), meniscal calcification in 30 (93.8%) soft tissue calcifications in 3 (9.4%) and erosions in 14 (43.8%). DECT images of 17 patients were observed in 17 knees in 25 sub regions and showed calcification within and around the tibio-femoral and patello-femoral joints in 15 (88.2%) knees. 41.2% had hyaline cartilage, 78.6% cruciate ligaments, 23.5% medial collateral ligament and 5.9% joint capsule calcifications. Nine patients had inflammation in the knee joint. These patients were subjected to Synovial Fluid aspiration. 4 out of these 9 showed presence of CPP crystals. Out of these 9 patients, 4 patients had meniscal calcification, 8 patients had cruciate ligament calcification, all 9 patients had cartilage calcification, and none had capsule calcification.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.