Abstract:Background: We used textural analysis matrix to examine the spatial distribution of pixel values and detect the compositional variation of repair cartilage with treatment of allogeneic human adipose-derived mesenchymal progenitor cells (haMPCs). Methods: Eighteen patients were divided randomly into three groups with intra-articular injections of haMPCs: the low-dose (1.0×107 cells), mid-dose (2.0×107), and high-dose (5.0×107) group with six patients each. 3D texture analyses based on gray level run-length matrix (GLRLM) of the segmented ROIs on MRI relaxation time maps including T1rho, T2, T2* and R2*. Five GLRLM parameters were analyzed, including run length non-uniformity (RLNonUni), grey level non-uniformity (GLevNonU), long run emphasis (LngREmph), short run emphasis (ShrtREmp) and fraction of image in runs (Fraction). We used the difference before and after treatment (D values) as the object to avoid errors caused by individual differences. Two-tailed Pearson linear correlation analysis was used to investigate correlations between texture parameters and the WOMAC scores. Results: The heterogeneity of spatial distribution of MRI relaxation time mapping pixels from three groups was decreased to varying degrees at 48 weeks after intra-articular injection of haMPCs. Spatial distribution of cartilage relaxation time maps pixels were uneven and layered, especially in T2 maps. Compared with base time, there were significant differences among three dose groups in GLRLM features for T1rho map including RLNonUni, GLevNonU, LngREmph, for T2 map including LngREmph, GLevNonU, ShrtREmp, for T2* map including RLNonUni, GLevNonU, and for R2* map including RLNonUni, GLevNonU. WOMAC pain scores were associated with RLNonUni of T1rho map, GLevNonU of T2 map, LngREmph of T2* map, LngREmph of R2* map and Fraction of T1rho map, whereas no significant correlations in other measurements.Conclusions: MRI texture analysis of cartilage may allow detection of the compositional variation of repair cartilage with treatment of allogeneic haMPCs. This has potential applications in understanding mechanism of stem cells repairing cartilage and assessing response to treatment.Trial registration: Clinicaltrials, NCT02641860. Registered 3 December 2015.https://www.clinicaltrials.gov/ct2/show/NCT02641860

Journal Link: 10.21203/rs.3.rs-1157978/v1 Journal Link: Publisher Website Journal Link: Download PDF Journal Link: Google Scholar