MAGNETIC RESONANCE IMAGING FEATURES OF LUMBAR LESIONS IN PATIENTS IN THE ACUTE STAGE OF ANKYLOSING SPONDYLITIS

Abstract

Objective To investigate the magnetic resonance imaging (MRI) features of lumbar lesions in patients in the acute stage of ankylosing spondylitis (AS), as well as the distribution, involvement, and pathological features of lumbar lesions in the acute stage of AS based on Berlin score. Methods A total of 70 patients with AS who were admitted to Department of Rheumatology, Shanxian Central Hospital, from 2019 to 2022 were enrolled, and related data were collected, including general information, human leukocyte antigen-B27 (HLA-B27) on admission, and lumbar MRI findings. The MRI findings, distribution characte-ristics, and extent of involvement of lumbar lesions were analyzed. The vertebral units were divided into three segments, i.e., T12-L2 as the upper segment, L2-L4 as the middle segment, and L4-S1 as the lower segment, and Berlin score was determined for the affected vertebral units and was compared between different segments of vertebral units. The Pearson or Spearman correlation analysis was used to investigate the correlation between age, course of disease, HLA-B27, and Berlin score. Results Of all patients, there were 52 cases (74.3%) of vertebral corner inflammatory lesion, mainly involving the anterior horn of vertebral body; there were 18 cases (25.7%) of discitis, mainly with diffuse involvement. There was a significant difference in the ove-rall distribution of Berlin score between vertebral units in different segments (χ2=20.425,P<0.01); the number of vertebral units with a Berlin score of 2 points in the middle and lower segments was significantly higher than that in the upper segment (P<0.05), and the number of vertebral units with a Berlin score of 3 points in the lower segment was significantly higher than that in the upper and middle segments (P<0.05). There was no correlation between age, course of disease, and Berlin score in the patients in the acute stage of AS (P>0.05), and there was a weak positive correlation between HLA-B27 on admission and Berlin score (r=0.240,P<0.05). Conclusion In the acute stage of AS, lumbar lesions have the characteristics of the involvement of multiple vertebral units and multifocal distribution, with the MRI manifestations of vertebral corner inflammatory lesion, discitis, and the mixture of both types of inflammation due to the presence of intervertebral facet joint arthritis. Severe lumbar lesions in the acute stage of AS often involve the vertebral units in the lower segment.

Keywords

• spondylitis, ankylosing|lumbar vertebrae|magnetic resonance imaging|hla antigens