Figure 3.

depicts color T₂ maps (beneath which is the reference gray scale image generated from the shortest echo image of the T₂ mapping sequence) obtained in vivo in a 3T MR scanner in the coronal plane 11 weeks after vascular interruption surgery in goat 3 (Panels A and B). Panel A demonstrates normal epiphyseal cartilage of the medial femoral condyle in the left unoperated (control) limb. Red oval marks an area of increased relaxation time, consistent with ischemic cartilage necrosis, and a mild delay in the progression of the ossification front in the operated right medial femoral condyle (Panel B). Increased relaxation time and mild delay in the progression of the ossification front (inset, red arrowheads) in the area of ischemic cartilage necrosis are apparent in the T₂ map obtained at 9.4T ex vivo of the same goat (Panel C). Areas of ischemic chondronecrosis are marked by pallor in safranin O stained histological section of the operated right medial femoral condyle (Panel D). Hematoxylin and eosin stained section at 40 × (inset) showing the interface of necrotic (above dotted line) and viable (below dotted line) epiphyseal cartilage from the area identified with the black rectangle in panel D. Black arrows indicate the surgical scars (Panels B–D).