<prompt> 60 yrs old male with bony abnormality at upper tibia associated with sensorineural hearing loss. On laboratory examination serum alkaline phosphatase levels are 440 mU1 elevated and serum Ca2 and P042- are normal. Skeletal survey shows ivory veebrae and cotton wool spots in x-ray skull. Diagnosis is:Fibrous dysplasiaPaget diseaseOsteosclerotic metastasisOsteoporosis  <response>: Serum alkaline phosphatase ALP is in Pagets disease elevated but calcium, parathyroid hormone, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D levels are normal. Cranial expansion may narrow cranial foramens and cause neurologic complications including hearing loss from cochlear nerve damage from temporal bone involvement. Skull radiographs reveal regions of cotton wool, or osteoporosis circumscripta, thickening of diploic areas, and enlargement and sclerosis of a poion or all of one or more skull bones. Veebral coical thickening of the superior and inferior end plates creates a picture frame veebra. Diffuse radiodense enlargement of a veebra is referred to as ivory veebra. Ref: Favus M.J., Vokes T.J. 2012. Chapter 355. Pagets Disease and Other Dysplasias of Bone. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo Eds, Harrisons Principles of Internal Medicine, 18e. 