Automated Assessment of Developmental Levels of Epiphysis by Support Vector Machine / 法医学杂志

ABSTRACT

Objective To realize the autom ated assessm ent of the levels of epiphysis of distal radius and ulna by support vector m achine (SVM). Methods The X-ray film s of the leftwrist jointswere taken from 140 teenagers aged from 11 to 19 years old as training sam ples. The levels of epiphysis of distal radius and ulnawere divided into five developm ental levels. Each level contained 28 sam ples. A nother 35 cas-eswere selected as independent verifying sam ples. SVM classification m odels of the five developm ental levels of epiphysis of distal radius and ulnawere established. The internal cross validationwas m ade by leave one out cross validation (LOOCV ),while the external validationwas m ade by histogram of orient-ed gradient (HOG), and then the accuracy (PA ) of testing resultswas calculated, respectively. Results The PA of SVM, LOOCV and HOG of distal radius epiphyseal levelwere 100%, 78.6%, and 82.8%, respec-tively;whereas the PA of SVM, LOOCV and HOGof distal ulna epiphyseal levelwere 100.0%, 80.0%and 88.6%, respectively. Conclusion The SVM -based autom atic m odels of the growth stage of distal ra-dius and ulna appear to have certain feasibility, and m ay provide a foundation for software developm ent of bone age assessm ent by forensic medicine.