A new cylindrical phantom for eye lens dosimetry development

Due to the recent new interest of the dosimetric community generated by evidence of larger number of induced cataracts for the same absorbed dose, in the frame work of the ORAMED project (Oramed, 2008) a task was devoted to the critical revision of the eye lens dose assessment procedures. The present paper summarizes the Monte Carlo analyses carried out to optimize the Hp(3,Ω) calculations in order to produce a set of conversion coefficients Hp(3,Ω)/Ka as close as possible to those of the limiting quantity HT(eye lens)/Ka. Comparison were carried out with already published values calculated for a previous theoretical phantom, mainly suited for the calculations of Hp(10,Ω)/Ka.

► The paper presents a critical revision of eye lens dosimetry issues.
► A proposal of a new cylindrical phantom, close to the head shape, was formulated.
► The theoretical phantom is suited to calculate new conversion coefficients for eye lens exposures.
► Monte Carlo was employed for the calculations vs photon energy and incident angle.
► A corresponding plastic water filled calibration phantom was designed.