A. Well demarcated.
- A lesion with a well-defined sclerotic edge is almost certainly benign, e.g. a fibrous cortical defect or a bone island.
B. Wide zone of transition: between the normal and abnormal bone.
- A lytic area with an ill-defined edge is likely to be aggressive.
C. Lytic area with no sclerotic rim,
- which may be a benign or malignant leson. Metastases and myeloma are a frequent cause of this pattern.
