MRI Findings In Gouty Arthritis Of The Knee And Its Correlation With Serum Uric Acid Levels

Objective:To investigate the imaging features of MRI in the patients with gouty arthritis of the knee,analysing the relationship between them,and explore the correlation between MRI manifestations and serum uric acid levels as well as duration of gouty arthritis preliminarily,so as to lay the imaging foundation for clinical diagnosis and treatment of gout.Methods:39 cases of MRI and clinical data with clinically confirmed gouty arthritis of the knee were collected.26 cases of unilateral knees and 13 cases of bilateral knees suffered from gouty arthritis were included,with a total of 52 cases of diseased joints.All of the images of MRI were analyzed,and the major observation indicators comprised the following:bone erosions,bone marrow edema,tophi,synovial thickening,soft tissue swelling,joint effusion and joint space.Data were statistically analyzed using C hi-square test and Spearman?s rank correlation test.Result:1.MRI manifestations of 52 cases of gouty arthritis of the knee were as follows.Bone erosions were detected in 30 cases,19 cases of which varied degrees of irregular cystic bone destruction,while 11 cases with bone cortex edge oppressive changed.21cases of bone marrow edema were observed,17 cases of which were mild,with low signal intensity on T1WI and high signal intensity on PDWI fat suppression.32 cases of tophi were observed,25 cases of which were located within the joints.The morphology of tophi diversified,and clusters and strips were the most common types.The signal of tophi was low on T1WI,but mainly mixed or high signal intensity on PDWI fat suppression.38cases of synovial thickening,42 cases of soft tissue swelling and 48 cases of joint effusion were also observed.2.There was no statistically significant difference of bone marrow edema between the group with bone erosions and the group without bone erosions in gouty arthritis of the knee(c~2=1.162,P>0.05),while the difference of tophi between them was statistically significant(c~2=10.211,P<0.01).3.The difference of bone erosions between the group with gouty arthritis and the group with gout combined with osteoarthritis was statistically significant(c~2=5.542,P<0.05),as well as the difference of tophi(c~2=6.502,P<0.05),while there was no statistically significant difference of bone marrow edema between them(c~2=0.607,P>0.05).4.The correlation coefficient between duration of gout and bone erosions,bone marrow edema,and tophi were 0.321(P<0.05),0.126(P>0.05)and 0.348(P<0.05),respectively.5.The correlation coefficient between serum uric acid levels and bone erosions,bone marrow edema,tophi were 0.281(P<0.05),0.177(P>0.05)and 0.313(P<0.05),respectively.Conclusion:The MRI features of gouty arthritis of the knee are characteristic,especially in the presence of tophi,which can help in diagnosing gout.Bone erosions are associated with tophi but not bone marrow edema.Gout combined with osteoarthritis will aggravate the seriousness of bone erosions and tophi.The duration of gout or levels of serum uric acid are both correlated with bone erosions and tophi but not bone marrow edema.