CT and MRI Analysis of Gouty Arthritis in the Knee

Objective: To explore the CT and MRI features of gouty arthritis in the knee. Method: The CT(12) and MRI(14) features of 21 patients with pathologically confirmed gouty arthritis in the knee were analyzed retrospectively. Results: Tophus was found in all patients, including 45 cases of CT, 48 cases of MRI. There were58 tophus deposited in ligaments and tendons, 15 in synovium or intra-articular, 11 in the bone, 10 in other places.Tophus showed strip 31, nodular 31, linea 4, or irregular contour 27. 21 lesions of bone erosion were found in CT,24 lesions in MRI. 30 lesions of bone erosion were found located in the edge of bones. Bone edema was found around 5 lesions of bone erosion on MRI imagings. On T1WI imagings, the tophus showed hypointensity to isointensity. On T2WI imagings, 6 tophus showed hyperintensity, 3 tophus showed hypointensity, and 39 tophus showed heterogeneously signal intensity. CT showed 21 tophus, whereas MRI showed 18 tophus in 5 patients who received both CT and MRI scan. 12 lesions of bone erosion were found on CT, MRI, respectively. 4 lesions of bone edema and 5 lesions of cartilage abnormal were found on MRI. Conclusion: Some image features of gouty arthritis in the knee are specific. CT may best evaluate tophus, whereas MRI is suitable to evaluate soft tissues,inflammatory changes. Comprehensive analysis of multiple imaging examinations is helpful for the diagnosis of gouty arthritis.