Single photon absorptiometry imaging as a screening method for diminished dual photon density measures

Scanning of the new 5-mm distal-radius site and the mid-radius (33% site) was performed using single photon absorptiometry (SPA) and of the L2-L4 region of the spine using dual photon absorptiometry (DPA) in a group of healthy women (age range 36-66 yr) in order to develop parameters to enable SPA to be used to screen for low DPA measures. The study data were analyzed as follows: 1. Women were classified as either 'intact' or 'post pelvic surgery' and the data for the two groups were separated. 2. Each SPA measurement was scrutinized and the one which produced the lowest score (% young normal [YN]) was entered for data analysis and graphing. The application of these two analytical discriminators represents a new approach in the biomedical literature. The findings were as follows: 1. When women were separated according to whether they were intact or had undergone pelvic surgery, the threshold value for screening using radius measures among intact women was set at 80% YN. 2. The necessary threshold value for the pelvic-surgery group needed to be set higher, at 93% YN. 3. If either the distal density or the mid-shaft density was below its threshold level, DPA was indicated. 4. At these threshold levels, no women with diminished spinal density (less than 83% YN) were omitted from screening procedure. We conclude that by refining our evaluation of each healthy woman according to her pelvic physiology status (intact or post-surgery) and considering whether either of the two SPA measures is below the threshold value, we will be able to screen for diminished DPA density and thereby eliminate a significant number of expensive but uninformative DPA readings.