Comment on 'Monte Carlo calculated microdosimetric spread for cell nucleus-sized targets exposed to brachytherapy 125I and 192Ir sources and 60Co cell irradiation'. (26th October 2015)

• Record Type: Journal Article
• Authors: Lindborg, Lennart; Lillhök, Jan; Grindborg, Jan-Erik
• Is Part Of: Physics in medicine & biology. Volume 60:Number 21(2015:Nov.)
• Page Start: 8621
• Page End: 8624
• Publication Date: 2015-10-26
• Subjects: microdosimetry -- wall-effects -- standard deviation; Biophysics -- Periodicals; Medical physics -- Periodicals; 610.153
• DOI: 10.1088/0031-9155/60/21/8621
• Languages: English
• ISSNs: 0031-9155

Abstract

Abstract: The relative standard deviation, σ r, D, of calculated multi-event distributions of specific energy for 60 Co ϒ rays was reported by the authors F Villegas, N Tilly and A Ahnesjö ( Phys. Med. Biol . 58 6149–62). The calculations were made with an upgraded version of the Monte Carlo code PENELOPE. When the results were compared to results derived from experiments with the variance method and simulated tissue equivalent volumes in the micrometre range a difference of about 50% was found. Villegas et al suggest wall-effects as the likely explanation for the difference. In this comment we review some publications on wall-effects and conclude that wall-effects are not a likely explanation.