Dual photon absorptiometry using a gamma camera

The most common technique for bone mineral densitometry is Dual Photon Absorptiometry with a dedicated scanning device. In principle, a gamma camera could be adapted to perform the same function, but little work along these lines has been reported in the literature. Tests made using a standard gamma camera with a 153Gd source at the focus of a magnifying collimator show that satisfactory results can be obtained on water/aluminium phantoms. A calibration is used to help ensure long term precision and stability. Measurements made using the same equipment but 241Am/99mTc sources gave poor results.