The Assessment Of 3.0T MRI T2-mapping Quantitative Analysis For Diagnosis Of Cartilage Injury In Gouty Arthritis Of The Knee

Objective To analyse the 3.0T MRI features of gouty arthritis of the knee and to measure T2 relaxation time of knee cartilage in patients and healthy subjects.To evaluate the MRI value in diagnosing articular cartilage injury of knee joint by comparing MRI T2 value,T2-mapping appearances of knee joint cartilage injury in knee gouty arthritis.Materials and Methods Between December 2016 and February 2018,18 cases gouty arthritis of knee(16 patients)and 10 cases healthy subjects(7 patients)were chosen for MRI routine sequence and T2-mapping(T2 relaxation time)imaging by Siemens MAGNETOM Skyra 3.0T MRI.The diagnostic criteria for gout are strictly based on the criteria established by the American College of Rheumatology in 1977 and acute gouty arthritis of the knee occurred in the knee joint.To observe the imaging features of MRI routine sequence in gouty arthritis of knee.Cartilage injury were divided into mild(ICRS I-II)cartilage injury and severe(ICRS III-IV)cartilage injury by a standard of ICRS cartilage injury grade(class 0:no significant articular cartilage morphology and signal changes,smooth surface;class I: cartilage signal abnormalities,but normal cartilage morphology;class II: mild cartilage surface irregularities and/or localized cartilage defects depth of less than 50% of the total layer thickness;class III: severe cartilage surface irregularities,cartilage defect depth of more than 50% of the total layer thickness,but not involving the full thickness cartilage;class IV,the whole layer exfoliation,defect,exposed subchondral bone with or without subchondral bone signal change),T2 value in region of interest of knee cartilage(condyles medial and condyle lateral femur,condyles medial and condyles lateral tibiae)were measured respectively in T2-mapping imaging by the software of post processing.An independent sample t test was used to analyze the statistical difference of T2 between the interest of the knee joint in gout patients and the normal patients.To evaluate the value of T2 value and T2-mapping artificial color image on displaying cartilage injury.Results The average T2 relaxation time of normal group,and the group of cartilage injury in gouty arthritis of the knee were 37.97±3.81 ms and 44.29±4.98 ms.The T2 relaxation time of the articular cartilage injury group was higher than that of the normal group.In goutyarthritis of knee,the average T2 relaxation time of articular cartilage in medial and lateral area were 44.26±5.41 ms and 44.32±4.53 ms respectively;the average T2 relaxation time of anterior,lateral and posterior articular cartilage were 42.14±3.58 ms,46.33 ±5.03 ms and 44.42±5.31 ms respectively;and the average T2 relaxation time of mild and severe cartilage injury group were 44.08±3.29 ms and 49.57±5.56 ms.Significant difference of T2 relaxation time was found between normal group and cartilage injury group,mild and severe cartilage injury group(P<0.05).On the whole,the T2 values of the articular cartilage in gouty arthritis of the knee increased significantly compared with the healthy control group.Conclusion There is a significant difference of T2 value in the full-thickness articular cartilage between the gouty arthritis of the knee and the normal knee.And T2 value was highly related to the degree of cartilage injury.The T2 value of the articular cartilage could increase significantly with cartilage injury.T2-mapping imaging can be used as an diagnostic criteria for the diagnosis of gouty arthritis of the knee without morphological changes,and has high clinical value clinical.