Radiation dose to the eye lens from the CT portion of a PET/CT examination and possibilities of its reduction
Authors:
Jaroslav Ptáček () 1,2,3; Pavel Koranda () 2; Iva Metelková () 2,3
Authors place of work:
Oddělení lékařské fyziky a radiační ochrany, Fakultní nemocnice Olomouc
1; Klinika nukleární medicíny LF UP a Fakultní nemocnice Olomouc
2; Ústav zobrazovacích metod FZV UP Olomouc
3
Published in the journal:
NuklMed 2012;1:63-67
Category:
Original Article
Summary
Introduction:
PET/CT examination is vital for oncological patients nowadays. ICRP in its document Statement on Tissue Reactions ref 4825-3093-1464 proposes a new threshold of radiation absorbed dose in an eye lens for radiation induced cataract in the level of 500 mGy. It could be possible to achieve this value in a current clinical practice (especially during repeated CT examinations of a head). The goal of our study is to provide information about radiation dose to the eye lens from the CT portion of a PET/CT examination including possibilities of its reduction.
Material and methods:
We analyzed radiation absorbed dose to the eye lens in patients evaluated with a PET/CT in the Department of Nuclear Medicine of the University Hospital in Olomouc. Absorbed dose in the eye lens was determined for a PET/CT of a torso, brain, whole-body and for the CT used for attenuation correction. We evaluated 8 patients for calculation the dose from a torso and a whole-body examination including a head, respectively. Only one study was used for the dose calculation during a brain examination and an attenuation correction, respectively.
Results:
Eye lens radiation absorbed dose calculated by ImPACT program was 6 mGy, 3.7 mGy, 49 mGy and 1.4 mGy during examination of a torso, whole-body, brain and during attenuation correction examination, respectively.
Conclusion:
Our calculated values are in accordance with a literature. The highest eye lens radiation absorbed dose is from the brain examination. However, like in ther cases, it is still far under the threshold for a radiation induced cataract.
Key Words:
PET/CT, radiation absorbed dose, eye lens
Zdroje
1. ICRP. Statement on Tissue Reactions. 2011; ICRP ref 4825-3093-1464
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Štítky
Nuclear medicine Radiodiagnostics RadiotherapyČlánok vyšiel v časopise
Nuclear Medicine
2012 Číslo 4
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