ADMINISTERED ACTIVITY OF TC-99(M)-DMSA FOR KIDNEY SCINTIGRAPHY IN CHILDREN

Kidney scintigraphy using Tc-99(m)-dimercaptosuccinic acid (DMSA) is a common gamma camera investigation in paediatric patients The present study deals with methods of calculating the activity to be administere d to children. Our aim is to find a method of calculation which gives the same count density in the gamma camera images for all ages. Four d ifferent methods, based on body weight, height, body surface area and a theoretical model, are compared. The count density in the images of the kidneys was studied retrospectively in 85 patients aged between 3 weeks and 19.5 years. Fourteen young adults aged 22.0-31.9 years were also studied. Two of the calculation methods, based on body surface ar ea and the theoretical model, showed no apparent age dependency (i.e. a constant count density was observed for all ages). The variation bet ween individuals was similar with both methods, but only the body surf ace area method gave a count density comparable to that for the young adults. As the method based on body surface area is also easy to imple ment, this method is recommended. ((C) 1998 Lippincott-Raven Publisher s).