Improving osteoporosis diagnosis in children using image texture analysis

Bone mineral density (BMD) is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk. From a technical point of view Quantitative Computed Tomography (QCT) should be the gold standard in bone densitometry. On the other hand, it is known that a greater percentage increase in skin dose is needed as the patient size is increased: positive results and side effect of long-term steroid treatment as obesity have been found for Duchenne muscular dystrophy (DMD), characterized by a progressive muscle degeneration and substitution with fat. The present work is an effort to improve osteoporosis diagnostic efficacy in children by analyzing the trabecular bone texture in CT L3 vertebra by two methods which are independent of image intensity: fractal dimension with power spectrum and wavelet packets. As results, comparing healthy children (44 children both sexes) with osteoporotic subjects (13 adult women, aged 52–87 years) great differences were noticed in all image texture indicators (p<0.0146). For DMD children (7 boys, not overweight) classified by z-score as osteoporotic because of their low BMD, texture image analysis did not exhibited high spatial frequencies as in the osteoporotic group; the probability that these two groups were similar was weak (p<0.0059), suggesting a more similar bone condition to normal or osteopenia. None of the pediatric groups exhibited as high spatial frequencies as did the osteoporotic women group. These analyses could help to determine osteoporosis in children, where it is often a diagnostic challenge.