CORRECTING METHOD FOR MEASURED VALUE OF BONE DENSITY BY MEANS OF SCANNER

摘要

PURPOSE: To correct an X-ray concentration measured value of a lumbar vertebra according to a conformation of a patient by arranging a calibration model under a model imitated after the human body, and arranging a water bag even on a human body model when the bone concentration of a lumbar vertebra is measured. CONSTITUTION: A model 37 of the body of a patient having a small conformation, in which an insert 39 which is imitated after a lumbar vertebra and houses a dipottasium hydrogenphosphate (K2 HPO4 ) solution having the concentration A0 is arranged, is arranged in a scanning field of a scanner of X-rays. A calibration model 40 having an insert 41', housing water and an insert 42' housing the K2 HPO4 solution having the high concentration, is arranged under this model 37, and the concentration of solution housed in the inert 39 imitated after a lumbar vertebra, the concentration of water housed in calibration inserts 41' and 42' and the concentration of solution having the high concentration are measured. Next, after a water bag 43 is arranged on the imitative model 37, a change in the concentration of the solution housed on the calibration inserts by the existence of the water bag 43, is calculated by a prescribed formula. Next, on (n) pieces of inserts imitated after a lumbar vertebra containing solution having the concentrations A1 to An different from A0 , a change values of the similarly found respective concentrations are obtained, and are corrected by a prescribed formula.