Possibilities of magnetic resonance imaging in the diagnosis of acute aseptic sacroilitis in children

Abstract

INTRODUCTION: Children and adolescents with juvenile spondyloarthritis (JSA) are at risk of developing sacroiliitis. MRI is the most preferred method of diagnosing sacroiliitis in adults over radiography and computed tomography. However, in the case of diagnosing childhood sacroiliitis, there is little information about the capabilities of MRI, and the reliability of the results in studies varies.OBJECTIVE: To show the possibilities of MRI in the diagnosis of infectious-allergic sacroiliitis.MATERIALS AND METHODS.: In this report, we present an analysis of data from 16 patients with aseptic (infectious-allergic) sacroiliitis only. Boys and girls aged 6 to 17 years (mean age 12.2±4.9) were equally divided. Magnetic resonance imaging, including contrast-enhanced imaging (used in 14 patients out of the total), was performed on a 3 T scanner (Achieva dStream Phillips) using a standard protocol that included multiplanar 3D T1-, T2WI, FLAIR and STIR with oblique coronal projection, diffusion-weighted images (DWI).RESULTS: MRI in all 16 patients revealed changes, even in those cases when X-ray and CT did not reveal pathological changes in bone or the changes were on the verge of normal (n=15). Of the 16 children, 10 (62.5%) had unilateral changes (50% on the right, 50% on the left) and six (37.5%) had bilateral changes. The bone marrow edema affected the sacrum in 10 patients, the ilium in three, and both bones of the joint in three patients. On DWI (10 children), increased diffusion was observed in five patients, on the right — in three, and on the left — in two patients.CONCLUSION: Currently, the best imaging modality for suspected acute sacroiliitis is MRI, which is more sensitive and specific, allowing early diagnosis of the disease and, accordingly, initiation of treatment, improving the prognosis. Disadvantages of MRI are long scan times, susceptibility to motion artifacts that require sedation or anesthesia in young children.