Fig. 16

Activity changes in AS by MRI. Sagittal STIR of (a) the cervico-thoracic and (b) the lumbar spine of the patients shown in Fig. 10 obtained 3 years before the radiography. There are multiple high signal intensity areas corresponding to vertebral corners (white arrows). Additionally, osseous oedema of the costo-vertebral joints (a, black arrows) seen on the lateral sagittal slice of the thoracic spine. (c) Axial post-contrast T1FS of an inflamed costo-vertebral joint confirmed the presence of joint inflammation in the form of osseous enhancement in both the vertebra and the rib (arrows) in addition to joint erosion. (d) Midline sagittal post-contrast T1FS shows an enhancing syndesmophyte. (e) Inflammatory changes at the apophyseal joint in a 27-year-old man; sagittal STIR image of the lumbar region showing subchondral osseous oedema in the lower thoracic region (white arrows), and both osseous and soft tissue oedema corresponding to the lumbar apophyseal joints (black arrows). Note that the osseous oedema in the pedicle of Th12 extends to the region of the costo-vertebral joint. (f) Coronal post-contrast T1FS of the lumbar spine shows additional enhancement corresponding to the interspinous ligament between L2 and L3 (arrows)