Question

X-ray of skull showing which lesions in the brain:

• A. Paget's disease
• B. Multiple myeloma
• C. Osteosarcoma
• D. Osteomyelitis

Hint:

Cotton-wool mixed lytic-sclerotic skull with thickened diploe, inner table spared.

Answer 1

The Correct Option is A

Step 1: The skull radiograph shows mixed lytic and sclerotic patches giving a fluffy cotton-wool appearance with thickening of the diploic space and outer table. This is classic for Paget disease of bone.
Step 2: Paget disease is a chronic disorder of excessive abnormal bone remodeling that frequently affects the skull, pelvis, spine and proximal long bones. In the skull it starts as a destructive process of the outer table while sparing the inner table.
Step 3: The early destructive lytic phase is osteoporosis circumscripta; in the reparative stage there is pronounced sclerosis of the inner table, and the diploic spaces and outer table thicken, producing the widespread cotton-wool effect. The cranial cavity itself is not encroached upon.
Step 4: Why not the others - multiple myeloma gives sharply punched-out lytic lesions of uniform size without sclerosis; osteosarcoma shows an aggressive sunburst destructive mass; osteomyelitis shows ill-defined lysis with sequestrum. The cotton-wool sclerotic-lytic pattern is diagnostic of Paget disease.