For decades,106Ru/106Rh ophthalmic applicators have been widely used to treat intraocular malignancies with good clinical outcomes. Determining the dosimetry of such applicators is challenging because of their spherical shape, the low range of emitted betas and the steep gradients involved. Furthermore, there is a lack of dose distribution data in the literature for some applicator models. It is crucial to understand the generated dose distributions to improve the treatment planning process. This study aims to calculate the dose distributions in water for 12 commercially available 106Ru/106Rh ophthalmic applicators.
The applicators were modeled using the Monte Carlo (MC) code PENELOPE-2008.1. A planar nonclinical applicator was also simulated. Depth-dose profiles along the central axis and lateral dose profiles at several depths were calculated and compared with the available published measured and calculated data. In the absence of published data, measurements performed by the manufacturer were used.
For some applicators, the calculated results obtained in this work showed improved consistency with the available experimental data compared with previously published calculations. For others, the data calculated in this work represent the first published dose data.
The MC code PENELOPE-2008.1 can accurately calculate the dose distributions for106Ru/106Rh ophthalmic applicators. The obtained set of tabulated dose distribution values may be useful for quality assurance of treatment planning systems and as a reference for comparison with future measurements and calculations.
The author thanks Juan Francisco Calvo and Alejandro Seoane for providing insightful comments on the paper and Juan Carlos Ruiz Rodríguez for his help with ICRU Report 56. The authors report no conflicts of interest in conducting the research. In this paper certain commercially available products are identified by name. These identifications are made for informational purposes only and do not imply endorsement by the author or by his institution.
I. INTRODUCTION II. METHODS II.A. 106Ru/106Rh applicators II.B. Simulation conditions III. RESULTS AND DISCUSSION III.A. Planar applicator III.B. CCX/CCY/CCZ applicators III.C. CXS applicator III.D. CCC applicator III.E. CCD applicator III.F. CGD applicator III.G. CIA applicator III.H. CIB/CIB-2 applicators III.I. CCA applicator III.J. CCB applicator IV. FINAL REMARKS V. CONCLUSIONS