COMS 24 mm

Eye Plaque Description

The dimensions of the 24 mm eye plaque are available here (given in Cutsinger et al ¹ study). The plaque has indentations for 33 seeds within Silastic insert  (seed coordinates here) in the Modulay backing, as shown in the above figures (generated using egs_view). The 3D dose distributions for the plaque containing ¹²⁵I (6711), ¹⁰³Pd (200), and ¹³¹Cs (CS-1 Rev2) (Ref. 2) are provided here (normalized per unit seed air kerma strength):  

• HOMO (33 seeds modelled under TG43 conditions) and HETERO (fully-loaded eye plaque in water) for ¹⁰³Pd: Zipped archive
• HOMO (33 seeds modelled under TG43 conditions) and HETERO (fully-loaded eye plaque in water) for ¹²⁵I: Zipped archive
• HOMO (33 seeds modelled under TG43 conditions) and HETERO (fully-loaded eye plaque in water) for ¹³¹Cs: Zipped archive

  Central axis depth dose curves

Doses along the plaque's central z-axis (CAX) for HOMO and HETERO scenarios are presented here for three radionuclides. Overall,  HETERO doses are lower than the HOMO doses, due to the attenuation and scattering in the backing and insert. For instance, HETERO/HOMO dose ratio at 0.5 cm along the CAX is 0.80, 0.87, and 0.88 for ¹⁰³Pd, ¹²⁵I, and ¹³¹Cs, respectively.  

103Pd model 200	125I model 6711	131Cs (CS-1 Rev2)

 Transverse dose profile

Transverse dose profiles (along x and y axes) at depths of z = 0.5 cm and z = 1 cm are shown for three radionuclides.

103Pd, x view, z =0.5 and 1 cm	103Pd, y view, z =0.5 and 1 cm
125I, x view, z =0.5 and 1 cm	125I, y view, z =0.5 and 1 cm
131Cs, x view, z =0.5 and 1 cm	131Cs, y view, z =0.5 and 1 cm

 References

Carleton Laboratory for Radiotherapy Physics