[A quantitative and quanlitative examination of bone metastases by whole body scanning with 99mTc-pyrophosphate...

The purpose of the present work is to "quantify" bone scanning, in order to calculate indices of localized uptake that will make it possible to differentiate between normal and pathological uptake, and approach an etiologicial diagnosis. The authors use an Elscint dual head whole body scanner and an offline video display calculator. The patient is given 8 mc technetium 99m pyrophosphate 4 hours prior to scanning. The whole body count is expressed in thousands of counts multipled by two so that the knee to whole body ratio is close to one, to facilitate comparison of the indices. Results show that the presence of metastases is demonstrated more clearly by using a ratio bone segment to whole body. Quantitative scanning with 99mTc-pyrophosphate makes it possible to: 1) detect bone metastases easily, 2) follow the metastases during treatment, 3) avoid the gross errors that can be made in nomquantitative scanning.