Perfusion in bone marrow lesions assessed on DCE-MRI and its association with pain in knee osteoarthritis: a cross-sectional study.

OBJECTIVE: To investigate the association between pain and perfusion in bone marrow lesions with and without cysts assessed dynamic contrast-enhanced (DCE)-MRI in patients with knee osteoarthritis. SUBJECTS AND METHODS: In a cross-sectional setting, perfusion in bone marrow lesions was assessed using 3 Tesla MRI and correlated (Spearman's rank correlation) to pain using the knee injury and osteoarthritis outcome score (KOOS). Bone marrow lesions were assessed across the whole knee with DCE-MRI using heuristic variable and non-contrast-enhanced-MRI using MRI osteoarthritis knee score. RESULTS: Data were available from 107 participants. The participants had a mean age of 60.8 years, mean BMI of 34.5 kg/m2, mean KOOS-pain of 63.7 (0-100 scale), and mean bone marrow lesion sum score of 6.5 (0-45 scale). The bivariate association between KOOS-pain and the heuristic perfusion variable time to peak in bone marrow lesions containing subchondral cysts showed a statistically significant correlation (r = 0.40; p = 0.002). The perfusion variables were not correlated with KOOS-pain in bone marrow lesions without cysts. CONCLUSION: In this cross-sectional study, the rate of perfusion (TTP) in bone marrow lesions containing subchondral cysts was associated with pain in patients with knee OA. DCE-MRI has a potential to be used for separating subtypes of OA.

Delayed gadolinium-enhanced MRI of menisci and cartilage (dGEMRIM/dGEMRIC) in obese patients with knee osteoarthritis: Cross-sectional study of 85 obese patients with intra-articular administered gadolinium contrast.

BACKGROUND: Early cartilage changes in knee osteoarthritis (OA) can be assessed by both intravenous (i.v.) and intra-articular (i.a.) delayed gadolinium-enhanced MRI of cartilage (dGEMRIC). PURPOSE: To examine the relationship between i.a. dGEMRIC and delayed gadolinium-enhanced MRI of menisci (dGEMRIM), and to investigate if the approach can be used to assess the morphological degeneration of menisci in obese patients with knee OA. STUDY TYPE: Cross-sectional. POPULATION: Eighty-five obese patients with knee OA. FIELD STRENGTH/SEQUENCES: 1.5T. Inversion recovery sequence with four inversion times. ASSESSMENT: T1 relaxation times were calculated for posterior weight-bearing femoral cartilage and the posterior horns of the menisci. Meniscus degeneration sum score (0-2) was assessed as increased signal/no signal (1/0) and tear/no tear (1/0). STATISTICAL TESTS: T1 relaxation times were compared using Student's t-test. Comparison of cartilage and meniscus T1 relaxation times was done by regression analysis. Analysis of variance (ANOVA) was used for comparison of meniscal T1 relaxation times among the three summed morphological scores (0-2). Statistical analyses were performed with a level of significance at 0.05. RESULTS: For lateral menisci, morphology sum scores of 0, 1, and 2 were found in 13, 58, and 14 patients and for medial menisci in 2, 30, and 30 patients, respectively. Mean T1 relaxation times were 441 msec, 480 msec, and 497 msec for cartilage, lateral menisci, and medial menisci, respectively. T1 relaxation times for the menisci were similar (P = 0.53), and a weak correlation was found between dGEMRIC and dGEMRIM in the lateral compartments (R = 0.26). Comparing dGEMRIM between different morphology sum scores showed no differences (P > 0.4). DATA CONCLUSION: I.a. dGEMRIM showed no correlation between the degree of meniscal degeneration and meniscus T1 relaxation times. I.a. dGEMRIM do not seem to deliver useful information about meniscus degeneration to be suitable for clinical applications, but i.a. dGEMRIC may still be considered an alternative contrast-saving method for cartilage. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;48:1700-1706.