Physical requirements of a 59Fe bone marrow distribution digital scanning study.

A method is described to provide whole-body scannings of 59Fe bone marrow distribution using a tungsten-alloy collimator. The physical requirements of this method were determined by means of dedicated phantoms. As we were only interested in bounded 59Fe regions (sacral bone, liver and spleen), it was necessary to subtract the 59Fe activity in the blood. An estimate of this activity was obtained by means of 99mTc-labelled erythrocyte whole-body scanning to which a correction factor K was applied. The independence versus depth was performed by computing geometrical means of prone and supine images. The results of these experiments indicate the possible feasibility of a scanning method for a ferrokinetic study in place of the usual external counting.