<prompt> Browns tumour is seen in:HypehyroidismHyperparathyroidismOsteoporosisOsteogenesis imperfecta  <response>: Advanced primary hyperparathyroidism pathognomonic radiologic findings, which are best seen on x-rays of the hands and are characterized by subperiosteal resorption. The skull also may be affected and appears mottled with a loss of definition of the inner and outer coices. Brown or osteoclastic tumors and bone cysts also may be present. Ref: Schwazs principle of surgery 9th edition, chapter 38. 