OSTEOPOROSIS DIAGNOSING APPARATUS AND METHOD

摘要

The osteoporosis diagnosing apparatus of the invention radiates repeatedly an ultrasonic impulse Ai toward the bone Mb of an examinee and receives an echo Ae from the bone Mb. The received signal is converted into a digital echo signal through an A/D converter and the echo level is detected by a CPU. The CPU extracts the maximum echo level from among the echo levels detected in a given period of measurement to thereby calculate a bone acoustic impedance Zb based on the extracted maximum echo level and then calculate the bone density of the examinee based on the calculated acoustic impedance Zb. As the impedance Zb is expressed in the square root of the product of modulus of elasticity and density of a bone, decreases in both the modulus of elasticity and the density synergistically affect the impedance to remarkably decrease the same. Thus the bone acoustic impedance Zb serves as a good index in judging the bone density.