Dosimetry of Ru-106 (Rh-106) plaques:
The default parameters (C,R,b,v,k) for Cross's beta point kernel equation are from Cross, W.G. et al, Calculation of beta-ray dose distributions from ophthalmic applicators and comparison with measurements in a model eye, Med. Phys. 28(7), 2001, page 191. By default, these parameters are ignored by Plaque Simulator in favor of using the tabulated data itself rather than attempting to fit an equation to the data. From the Radial Dose tab you may optionally elect to generate Plaque Simulator's beta kernel using Cross's formula and these parameters if you wish.
From the older MIRD formalism:
- nβ is the average number of beta particles emitted per disintegration.
- k' is 0.0160 (1.6 x 10^-8 g-cGy/MeV * 10^6 dps/MBq).
- Eav is the average energy of the beta spectrum in MeV.
- The water to medium conversion factor described above may also be used to rescale the beta calculation. The default value for this factor is 1.
- The 90 percentile distance is the distance in mm from the source within which 90% of the energy is absorbed.
- The active and physical lengths for beta "point and patch" sources should be set to 0.1 mm.