Comparison of radiographic texture analysis from computed radiography and bone densitometry systems

Abstract

Osteoporosis is a disease that results in an increased risk of bone fracture due to a loss of bone mass and deterioration of bone structure. Bone mineral density (BMD) provides a measure of bone mass and is frequently measured by bone densitometry systems to diagnose osteoporosis. In addition, computerized radiographic texture analysis (RTA) is currently being investigated as a measure of bone structure and as an additional diagnostic predictor of osteoporosis. In this study, we assessed the ability of a peripheral bone densitometry (PD) system to yield images useful for RTA. The benefit of such a system is that it measures BMD by dual-energy x-ray absorptiometry and therefore provides high- and low-energy digital radiographic images. The bone densitometry system investigated was the GE/Lunar PIXI, which provides 512 x 512 digital images of the heel or forearm (0.2 mm pixels). We compared texture features of heel images obtained with this PD system to those obtained on a Fuji computed radiography (CR) system (0.1 mm pixels). Fourier and fractal-based texture features of images from 24 subjects who had both CR and BMD exams were calculated, and correlation between the two systems was analyzed. Fourier-based texture features characterize the magnitude, frequency content, and orientation of the trabecular bone pattern. Good correlation was found between the two modalities for the first moment (FMP) with r=0.71 (p value<0.0001) and for minimum FMP with r=0.52 (p value=0.008). Root-mean-square (RMS) did not correlate with r=0.31 (p value>0.05), while the standard deviation of the RMS did correlate with r=0.79 (p value<0.0001). Good correlation was also found between the two modalities for the fractal-based texture features with r=0.79 (p value<0.0001) for the global Minkowski dimension and r=0.63 (p value=0.0007) for the fractal dimension from a box counting method. The PD system therefore may have the potential for yielding heel images suitable for RTA.

Clinical Microwave Tomographic Imaging of the Calcaneus: A First-in-Human Case Study of Two Subjects

“…Current methods to detect osteoporosis or assess bone fracture risk include bone mineral density (BMD) exams—primarily DXA [15]. In clinical practice, these exams are performed at the most critical anatomical sites, e.g., the hip, spine, wrist, and ribs.…”

“…In general, the trabecular bone at these locations has a eightfold higher turnover rate than cortical bone; therefore, age and disease-related bone loss is more apparent at earlier stages in cancellous bone [3], [16]. While this technique provides a measure of the bone mass, it does not offer insight into bone structure or biology which are regarded as important components of bone health [15]. In fact, BMD values overlap for high and low fracture risks [15], [17].…”

La géométrie fractale pour l’analyse de signaux médicaux : état de l’art

“…Ces dernières années, les recherches concernant la caractérisation de la trabéculation osseuse par l'intermédiaire de l'analyse fractale, sont restées très dynamiques [117,132,190,193]. Plusieurs travaux se sont intéressés à l'anisotropie de la trabéculation osseuse [13].…”

Automatic selection of region of interest for radiographic texture analysis

“…1 Thus, radiographic texture analysis (RTA) is being investigated to characterize the bone trabecular pattern in order to assess bone fragility. [1][2][3][4][5][6] During RTA, computerized texture analysis is performed on the digital graylevel radiographic images using Fourier and fractal analyses. These computations yield information on the magnitude and spatial frequency content of the radiographic trabecular pattern.…”