Clinical interest of bone texture analysis in osteoporosis: a case control multicenter study.

UNLABELLED: We demonstrate the clinical interest of bone texture analysis with a new high resolution X-ray device. We have found that the combination of BMD and texture parameter values provided a better assessment of the fracture risk than that obtainable solely by BMD measurement. INTRODUCTION: Osteoporosis is characterized by BMD and trabecular bone microarchitecture. We have developed a new high-resolution X-ray device with direct digitization. The aim of this study was to demonstrate in a multicenter case control study the clinical interest of bone texture analysis with this new device. METHODS: In this cross-sectional multicenter case-control population study in post-menopausal women, 159 osteoporotic fractures were compared with 219 control cases. Images were obtained on calcaneus with a direct digital X-ray device (BMA, D3A Medical Systems). Co-occurrence, run-length matrices and the fractal parameter Hmean were evaluated. BMD was measured at the lumbar spine (LS), femoral neck (FN) and total hip (TH) by DXA. RESULTS: The three texture parameters were significantly lower in osteoporotic fracture cases than in control cases. These differences persisted after adjustment for TH BMD. Receiver operating characteristic curves were used to compare the discriminant capacity of texture parameters and BMD measurements for fracture. The highest areas under curve (AUC) were 0.721 for TH BMD and 0.706 for Hmean (AUC THBMD vs. AUC Hmean, p = NS). We determined the threshold between high and low Hmean parameter values and then the odds ratios (OR) of fracture for low Hmean, for BMD < or =2.5 SD in the T-score and for combinations of both parameters. The OR of fracture for low H was 2.72 (95% CI, 1.36-5.4). For a FN BMD < or = -2.5 SD, the OR of 4.78 (2.19-10.43) shifted to 14.06 (4.41-44.85) adding H. CONCLUSIONS: These data confirmed the clinical interest of the combination of BMD and texture parameters to improve the assessment of the risk of fracture other that obtainable by the sole BMD measurement.

Bone texture analysis on direct digital radiographic images: precision study and relationship with bone mineral density at the os calcis.

Assessment of bone microarchitecture in complement to bone mineral density (BMD) exam could improve prediction of osteoporotic fractures. A high-resolution X-ray prototype was developed to assess microarchitecture quality. Images were obtained on os calcis; then, three texture parameters were calculated on the same region of interest (ROI): a fractal parameter, a run-length parameter, and a co-occurrence parameter. This work describes the reproducibility of this method. We also examine the relationship between texture parameters and BMD at a site-matched ROI. Measurements on the left heel were performed on 30 healthy women, on the same day, with repositioning for short-term precision error. An additional measurement was done at 1 week to evaluate mid-term precision error on 14 subjects. Os calcis images from 10 healthy women were used to evaluate both intra- and interobserver reproducibility. Thirty other healthy patients were measured successively on two similar devices for interprototype comparison. BMD and texture analyses of the left heel were obtained from 57 women. Short-term precision errors ranged 1.16-1.24% according to the texture parameter. Mid-term precision error was slightly higher than short-term precision for the mean Hurst exponent parameter. Comparisons of texture parameters and BMD at a site-matched ROI on the os calcis showed no significant relationships. The results also show that the use of this high-resolution digital X-ray device improves the reproducibility of parameter measurement compared to the indirect digitization of radiologic films previously used.