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BACKGROUND: Growing evidence suggests that marrow adipocytes play an active role in the regulation of bone metabolism and hematopoiesis. However, research on the relationship between bone and fat in the context of hematological diseases, particularly ß-thalassemia, remains limited. PURPOSE: To investigate the relationship between marrow fat and cortical bone thickness in ß-thalassemia and to identify key determinants influencing these variables. STUDY TYPE: Prospective. SUBJECTS: Thirty-five subjects in four subject groups of increasing disease severity: 6 healthy control (25.0 ± 5.3 years, 2 male), 4 ß-thalassemia minor, 13 intermedia, and 12 major (29.1 ± 6.4 years, 15 male). FIELD STRENGTH/SEQUENCE: 3.0 T, 3D fast low angle shot sequence and T1-weighted turbo spin echo. ASSESSMENT: Analyses on proton density fat fraction (PDFF) and R2* values in femur subregions (femoral head, greater trochanter, intertrochanteric, diaphysis, distal) and cortical thickness (CBI) of the subjects' left femur. Clinical data such as age, sex, body mass index (BMI), and disease severity were also included. STATISTICAL TESTS: One-way analysis of variance (ANOVA), mixed ANOVA, Pearson correlation and multiple regression. P-values <0.05 were considered significant. RESULTS: Bone marrow PDFF significantly varied between the femur subregions, F(2.89,89.63) = 44.185 and disease severity, F(1,3) = 12.357. A significant interaction between subject groups and femur subregions on bone marrow PDFF was observed, F(8.67,89.63) = 3.723. Notably, a moderate positive correlation was observed between PDFF and CBI (r = 0.33-0.45). Multiple regression models for both PDFF (R2 = 0.476, F(13,151) = 10.547) and CBI (R2 = 0.477, F(13,151) = 10.580) were significant. Significant predictors for PDFF were disease severity (ßTMi = 0.36, ßTMa = 0.17), CBI (ß = 0.24), R2* (ß = -0.32), and height (ß = -0.29) while for CBI, the significant determinants were sex (ß = -0.27), BMI (ß = 0.55), disease severity (ßTMi = 2.15), and PDFF (ß = 0.25). DATA CONCLUSION: This study revealed a positive correlation between bone marrow fat fraction and cortical bone thickness in ß-thalassemia with varying disease severity, potentially indicating a complex interplay between bone health and marrow composition. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.
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INTRODUCTION: Stroke recovery is a complex process influenced by various factors, including specific neural reorganization. The objective of this systematic review was to identify important functional connectivity (FC) changes in resting-state fMRI data that were often correlated with motor, emotional, and cognitive outcome improvement. METHOD: A systematic search using PubMed and SCOPUS databases was conducted to identify relevant studies published between 2010 and 2023. RESULTS: A total of 766 studies were identified, of which 20 studies (602 S individuals) met the inclusion criteria. Fourteen studies focussed on motor recovery while six on cognitive recovery. All studies reported interhemispheric FC to be strongly associated with motor and cognitive recovery. The preservation and changes of M1-M1 (eight incidences) and M1-SMA (nine incidences) FC were found to be strongly correlated with motor function improvement. For cognitive recovery, restoration and preservation of FC with and between default mode network (DMN)-related regions were important for the process. CONCLUSIONS: This review identified specific patterns of FC that were consistently reported with recovery of motor and cognitive function. The findings may serve in refining future management strategies to enhance patient outcomes.