[Quantitative computerized tomography of the vertebral spongiosa. Proposal of a method applicable to the study of postmenopausal osteoporosis].

A Quantitative Computed Tomography (QCT) method, simplifying the well-known technique proposed by Genant (1982) and applied to a standard third generation whole body CT scanner is described. This technique was applied in the measurement of the trabecular bone which has high sensitivity for metabolic changes. The BMC (Bone Mineral Content) measured in different groups of subjects (healthy postmenopausal patients versus women with postmenopausal osteoporosis) showed a highly significant difference (p less than 0.001). The precision of repositioning (coefficient of variation 1.8% to 2.3%, obtained in healthy male patients) and the good, linear relationship computed from the phantom values, minimize measurement errors. Since this method is quickly applied and involves low-dose radiation-exposure, it could be introduced in the clinical study of metabolic bone diseases.