Phantom Modification

Research with the Lung Phantom Modification (Size and Sliced) and Sliced BOMAB Phantom has continued with the following developments:

Modified LLNL Lung Phantom:

The lung shapes of the LLNL torso phantom have been modified by elongation of 10 cm. Comparison of the extended lungs with the original lungs has been made by measuring the two lung phantoms in the LLNL torso phantom using the HML's lung counting system. The results indicate that lung shape has little impact on the counting efficiency provided the photon energy is at or exceeds 45 keV. At a chest wall thickness of 3.99 cm the difference between the two lung shapes was found to be only a few percent.

Sliced LLNL Lung Phantoms:

Whole lung sets for a torso phantom suffer from potential manufacturing problems, and the amount of radioactivity in the lungs set cannot be altered after fabrication is completed. Lung sets with short lived radionuclides can only be used until the nuclides decay and then must be discarded and replaced. Sliced lung sets on the other hand, suffer none of these problems as it is simple to prepare the planar sources and they are easily replaced.

Sliced BOMAB (female) Phantom:

The HML has designed and manufactured a new type of BOMAB phantom corresponding to a female in size. The work done on this phantom show that the sliced phantom performs equivalently to a female BOMAB whose activity is dissolved in water and homogeneously distributed throughout each section. The advantage of the sliced phantom is that the sources are solid, sealed and cannot leak activity. The new phantom is therefore ideal for uses that involve shipment such as the international exercise. The phantom is also re-useable as the sources can be changed.