Axial spondyloarthritis (ax-SpA) is primarily manifested by active lesions (e.g., bone marrow edema) and structural lesions (e.g., bone erosion, sclerosis.), magnetic resonance imaging (MRI) is the primary method for detecting active lesions. In our previous study, although synthetic MRI Sequences can assess both structural through T1WI (T1 weighted image) sequence and active lesions through STIR, (Short TI Inversion Recovery) sequence, the assessment of structural lesions still mainly relies on…