Study On Quantitative Parameters Of Bone Marrow Infiltration In Patients With Acute Leukemia By IDEAL-IQ

Objective:To investigate the changes of proton density fat fraction(PDFF)and R2~*value in lumbar bone marrow infiltration in patients with acute leukemia(AL)by using the least squares estimated asymmetric echo iterative water-lipolysis quantitative sequence(IDEAL-IQ),and to explore the possible pathophysiological changes of bone marrow infiltration in AL patients by analyzing the correlation between imaging parameters and related laboratory indicators.Methods:This study enrolled patients clinically diagnosed with newly diagnosed untreated AL from June 2020 to June 2022 in the Department of Hematology of the Second Hospital of Shanxi Medical University,and age and gender matched healthy controls were collected.The age,serum lactate dehydrogenase(LDH)level and peripheral blood white blood cell(WBC)of AL patients were collected.All participants underwent lumbar bone marrow IDEAL-IQ examination.PDFF values and R2~*values of lumbar vertebral bone marrow were obtained by image post-processing.Independent sample t test was used to compare the difference of imaging parameter values between AL group and healthy control group.The receiver operator characteristic(ROC)curve was used to evaluate the diagnostic efficacy of each imaging parameter value.Spearman correlation analysis was used to analyze the correlation between PDFF value,R2~*value and laboratory indicators.P<0.05 was considered statistically significant.Results:A total of 58 AL patients were finally included in the analysis,including 30 males and 28 females,with a median age of 54(31,63)years.Fifty-eight healthy subjects were enrolled as the control group.The study values of the parameters of the 116 subjects were the average values of the three vertebral bodies of the lumbar spine.The PDFF and R2~*values of AL patients were significantly lower than those of healthy controls(P<0.05).The area under the ROC curve of PDFF and R2~*values was 0.973 and 0.79,respectively.There was a significant negative correlation between PDFF value and serum LDH level and peripheral blood WBC count in AL patients(r=-0.55,P<0.001;r=-0.66,P<0.001),and positively correlated with age(r=0.3,P<0.05),but not with the percentage of bone marrow blast(BM blast).There was no significant correlation between R2~*value and serum LDH level,peripheral blood WBC count,BM blast percentage and age in AL group(all P<0.05).Conclusion:The changes of PDFF and R2~*values of IDEAL-IQ in AL patients suggest the abnormality of bone marrow fat and iron metabolism.This study provides new ideas and methods for the study of the pathogenesis and development of AL based on the bone marrow microenvironment.