Tumors of bone and cartilage

Many pathological processes may involve the bony walls of the orbit. Inflammatory processes, such as sinusitis, and structural lesions, such as mucocele, may destroy the bone, as may deposits of metastatic carcinoma. Secondary involvement of the bone may occur with benign neoplasms, (e.g., meningioma of the sphenoid wing), and with infiltrative carcinomas of adnexal origin, (e.g., basal cell carcinoma). In this chapter, we shall concentrate on lesions that arise within the orbital bone and manifest as spaceoccupying tumors. Such lesions are relatively rare, comprising < 2% of all orbital tumors (128).