| 摘要 |
PURPOSE:To easily estimate absolute scattering strength from an interested area in which no blood exists by subtracting an average cumulative attenuation from scattering power measured with regard to the area where no blood exists, and also, normalizing it by transmitting power by a blood scattering power calculating means and an average cumulative attenuation calculating means. CONSTITUTION:An average cumulative attenuation calculating means 6 calculates an average cumulative attenuation being a difference in each depth (z) of both of blood scattering power calculated by a blood scattering power calculating means 5 and blood scattering power at the time when there is no attenuation derived in advance. A B-mode image correcting means 8 displays a B-mode image and absolute scattering strength of an interested area 13 by a numerical value, a color, etc. That is, the blood scattering power is derived in great quantities by coordinating it to the depth (z). (b) is derived as an attenuation coefficient PBZ of the whole tissue, and (c) derives an (a) average cumulative attenuation being a difference to a segment of the (b) inclination: the attenuation coefficient of the whole tissue from the blood scattering power when there is no attenuation. Subsequently, scattering power reflected from the interested area 13 is measured, the average cumulative attenuation is subtracted, transmitting power is subtracted, and absolute scattering strength bT is derived. |
