PROBLEM TO BE SOLVED: To provide a non-invasive and simple diagnostic device for dynapenia and a program for it. SOLUTION: A texture analysis is performed on an ultrasonic echo image based on a reflected wave obtained by irradiating a muscle to be measured with ultrasonic waves, and the result of the texture analysis is used to dynapenia (muscle strength) of the muscle to be measured. An image diagnostic device, a program, and an image analysis method that derive and output the degree of decrease). [Selection diagram] Fig. 1【課題】非侵襲的で簡便なダイナペニアの診断装置、そのためのプログラムの提供。【解決手段】測定対象筋肉に超音波を照射して得られる反射波に基づく超音波エコー画像に対してテクスチャ解析を行い、前記テクスチャ解析の結果を用いて、測定対象筋肉のダイナぺニア（筋力低下）の程度を導出して出力する、画像診断装置、プログラム及び画像解析方法。【選択図】図１
