Abstract
One-year-old male Persian cat presented with multiple fractures and no known traumatic history. Marked decrease of bone radiopacity and thin cortices of all long bones were identified on radiography. Tentative diagnosis was osteogenesis imperfecta, a congenital disorder characterized by fragile bone. To determine bone mineral density (BMD), quantitative computed tomography (QCT) was performed. The QCT results revealed a mean trabecular BMD of vertebral bodies of 149.9 ± 86.5 mg/cm(3). After bisphosphonate therapy, BMD of the same site increased significantly (218.5 ± 117.1 mg/cm(3), p ＜ 0.05). QCT was a useful diagnostic tool to diagnose osteopenia and quantify response to medical treatment.