Fractal Analysis of Trabecular Patterns in Projection Radiographs: An Assessment

RATIONALE AND OBJECTIVES.Fractal analysis of digitized images has been investigated in recent years as a potential measure of structural bone strength. Several technical issues associated with such measurements are assessed. METHODS.In a series of experiments using a hand phantom, the effects of system noise and modulation transfer function on fractal dimension were explored. The authors evaluated a method for correcting the estimated power spectrum using a step-wedge image exposed and digitized under identical conditions as a reference. RESULTS.System noise and modulation transfer function significantly affect estimated fractal dimension in bony regions computed from conventional radiographs. CONCLUSIONS.Before conventional radiographs are used for fractal analysis in the clinical environment, many of the technical problems associated with this methodology must be addressed.