X-Ray of the Skull in Paget's Disease

A typical mosaic pattern of areas of increased sclerosis and lucency is seen in this x-ray. These "cotton-wool" patches result from thickening of the calvarium.
By permission of the publisher. From Maricic M, Ko M: Atlas of Rheumatology. Edited by G Hunder. Philadelphia, Current Medicine, 2005. Available at www.images.md.