A new method for assessing 99Tcm-MDP bone uptake from a bone scan image: quantitative measurement of radioactivity in global skeletal regions of interest.
Bone uptake of 99Tcm-MDP was evaluated 4 h after injection in 27 normal subjects aged 23-50 years by gamma camera measurement of the activity in whole skeleton regions of interest (ROIs) in anterior and posterior projection. The mean global skeletal uptake (GSU) (% of whole-body activity in both projections measured 30 s after injection) was 33.5 +/- 4%. The standard urinary excretion method (whole-body retention, WBR) gave a mean bone uptake value of 31.5 +/- 4%. A significant correlation (r = 0.570; P less than 0.002) was found between GSU and WBR. The mean bone-to-soft tissue ratio (B/S index) was 3.0 +/- 1.1. It is suggested that this direct, external counting method provides a way of obtaining both a qualitative and a semiquantitative evaluation of bone uptake with a single tracer administration in a routine bone scan. Investigation of its use in the assessment of bone involvement in low and high turnover bone diseases is now under way.
D'Addabbo
A
A
Centro Interdipartimentale di Biocibernetica e Tecniche Radioisotopiche, Università di Bari, Italy.
Rubini
G
G
Mele
M
M
Lauriero
F
F
D000328:Adult; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000378:metabolism*; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D011877:Radionuclide Imaging; D012016:Reference Values; D013669:Technetium Tc 99m Medronate / Q000493:pharmacokinetics*
D013669:Technetium Tc 99m Medronate