Estimation of age from soft X-ray findings of Japanese pubic symphysis based on a image processing

A method for estimating the age at death through the image processing of soft X-ray pictures of pubic symphysis is reported. The collected 533 materials were sliced at the thickness of 5 mm. Prior to the image processing, subjective assessment was made on the five indices of gross morphological findings. The pictures showed roughening and darkening tendencies with age and two indices for image processing were introduced. Applying the natural logarithm to data obtained by the image processing and making regression analysis. two kinds of age estimation equations were derived in the form of; Y = -39.91 lnX + 189.63 and the estimated age Y was proportional to natural logarithm of measured indices X. The age estimation equations showed accuracies of 70% or more for the age range of +/- 5 years and 100% for +/- 8 years. The accuracy was satisfactory for age estimation in the field of person appraisal in legal medicine.