Figure 3. Avascular necrosis. 35-year-old female with bilateral hip pain at 1 year following a matched unrelated transplant. The patient had recently completed a course of steroids for an episode of GVHD. (a) Coronal T1 weighted MRI image of the hips and (b) sagittal T1 weighted MRI of the left hip showing a serpiginous zone of low signal around the avascular area (arrow).