1. Observed high incidence of prostatic calculi with the potential to act as natural fiducials for prostate image guided radiotherapy 
A.G.M. O'Neill, S.O. Osman, S. Jain, A.R. Hounsell, J.M. O'Sullivan 
Technical Innovations and Patient Support in Radiation Oncology  
Volume 9, Pages (March 2019)
DOI: /j.tipsro
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2. Fig. 1
Prostate Imaging and Reporting Data System (PI-RADS). Reproduced from Dickinson et al., European Urology 59, 477–494, 2011 [13].
Technical Innovations and Patient Support in Radiation Oncology  2019 9, 35-40DOI: ( /j.tipsro )
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3. Fig. 2
The total number of intra-prostatic calculi recorded was 695. PIRADs location 3p and 9p (posterior mid gland) exhibited the highest frequency of PC of 14.9% and 13.8%, respectively.
Technical Innovations and Patient Support in Radiation Oncology  2019 9, 35-40DOI: ( /j.tipsro )
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4. Fig. 3 Schematic to show TRUS PC and subsequent CT PC.
Technical Innovations and Patient Support in Radiation Oncology  2019 9, 35-40DOI: ( /j.tipsro )
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