Skull radiograph of a 60-year-old man with early Paget's disease shows a large, sharply demarcated radiolucent area in the frontal and parietal regions, with the outer table more affected than the inner table. This appearance is called:

• A Cotton wool appearance
• B Osteoporosis circumscripta ✓
• C Beaten copper appearance
• D Salt and pepper skull

Explanation

Osteoporosis circumscripta is the purely lytic phase of Paget's disease in the skull vault, seen as a well-defined geographic radiolucency affecting mainly the outer table. Cotton wool appearance represents the later mixed sclerotic phase with thickened disorganized trabeculae, which excludes option A. Beaten copper appearance reflects chronic raised intracranial pressure with gyral impressions, and salt and pepper skull describes primary hyperparathyroidism. Both mimic lytic calvarial lesions but have distinct clinical contexts.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.