[Structural quantification of bone from radiographs using power spectral analysis].
Bone mineral density (BMD) and bone structure are very important indices for prevention of fracture. However, it is very difficult to quantify bone structure, and only a few indices for structural quantification of bone have been reported. The purpose of this research was to investigate a new index for bone structure. The subjects were 52 women aged from 20 to 85 years. Directivity index (DI) is a new index of bone structure calculated by directivity of power spectrum from radiographs of metacarpal bone using fast Fourier transform (FFT). DI was obtained by subtracting the integral power value at 0 and 90 degree directions on the x-y plane of the two-dimensional power spectrum of bone from the integral power value at a direction of 45 degrees. A significant relationship between BMD and DI was indicated by correlation coefficient. However, no significant relationship between BMD and the first moment of the Fourier power spectrum or the fractal dimension was found. There is a possibility that DI estimates a slight deformation of bone structure. In the future, we will apply DI to the prevention of fractures and osteoarthritis.
Miyamura
T
T
Health Care Center, Yamanashi University.
Iijima
S
S
Yamagata
Z
Z
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011859:Radiography