Karl R D, Hartshorne M F, Cawthon M A, Bauman J M, Howard W H, Bunker S R
Clin Nucl Med. 1985 Jul;10(7):507-12. doi: 10.1097/00003072-198507000-00015.
The interpretation of Ga-67 scans is limited by the complex anatomic and physiologic distribution of Ga-67 and by the low resolution possible with this isotope. The use of a second isotope Tc-99m, tagged to an appropriate pharmaceutical allows the identification of anatomic landmarks. Computer acquisition of both the Ga-67 and Tc-99m images allows for subtraction of the Tc-99m images from the Ga-67 images and leads to precise localization of abnormal Ga-67 accumulations. Only a small percentage of the counts in the Tc-99m window are due to Ga-67 scatter and do not degrade the Tc-99m images. Cases illustrating the value of the dual-isotope technique are presented.
