A Ben Abdennebi1, S Aubry2, L Ounalli3, M S Fayache4, E Delabrousse2, Y Petegnief5. 1. Regional and University Hospital of Besançon, 25000 Besançon, France; Faculty of Mathematical, Physical and Natural Sciences of Tunis, 2092 El Manar, Tunis, Tunisia; Laboratory on Energy and Matter for Nuclear Sciences Development, LR16CNSTN02, Tunisia. 2. Regional and University Hospital of Besançon, 25000 Besançon, France; Nanomedicine Lab Imagery and Therapeutics EA 4662, University of Franche-Comte, 25000 Besancon, France. 3. National Center for Nuclear Sciences and Technology, 2020 Ariana, Tunisia; Laboratory on Energy and Matter for Nuclear Sciences Development, LR16CNSTN02, Tunisia. Electronic address: leila.ounalli@cnstn.rnrt.tn. 4. Faculty of Mathematical, Physical and Natural Sciences of Tunis, 2092 El Manar, Tunis, Tunisia; Laboratory on Energy and Matter for Nuclear Sciences Development, LR16CNSTN02, Tunisia. 5. Regional and University Hospital of Besançon, 25000 Besançon, France.
Abstract
PURPOSE: To estimate fetal absorbed doses for pregnant women pelvimetry, a comparative study between EOS imaging system and low-dose spiral CT-scanner was carried out. For this purpose three different studies were investigated: in vivo, in vitro and Monte Carlo calculations. METHODS: In vivo dosimetry was performed, using OSL NanoDot dosimeters, to determine the dose to the skin of twenty pregnant women. In vitro studies were established by using a cubic phantom of water, in order to estimate the out of field doses. In the latter study, OSLDs were placed at depths corresponding to the lowest, average and highest position of the uterus. Monte Carlo calculations of effective doses to high radio-sensitive organs were established, using PCXMC and CTExpo software suites for EOS imaging system and CT-scanner, respectively. RESULTS: The EOS imaging system reduces radiation exposure 4 to 8 times compared to the CT-scanner. The entrance skin doses were 74% (p-values <0.01) higher with the CT-scanner than with the EOS system. In the out of field region, the measured doses of the EOS system were reduced by 80% (p-values <0.02). Monte Carlo calculations confirmed that effective doses to organs are less accentuated for EOS than for CT pelvimetry. CONCLUSIONS: The EOS system is less irradiating than the CT exam. The out-of-field dose which is significant, is lower in the EOS than in the CT-scanner and could be reduced even further by optimizing the time used for image acquisition.
PURPOSE: To estimate fetal absorbed doses for pregnant women pelvimetry, a comparative study between EOS imaging system and low-dose spiral CT-scanner was carried out. For this purpose three different studies were investigated: in vivo, in vitro and Monte Carlo calculations. METHODS: In vivo dosimetry was performed, using OSL NanoDot dosimeters, to determine the dose to the skin of twenty pregnant women. In vitro studies were established by using a cubic phantom of water, in order to estimate the out of field doses. In the latter study, OSLDs were placed at depths corresponding to the lowest, average and highest position of the uterus. Monte Carlo calculations of effective doses to high radio-sensitive organs were established, using PCXMC and CTExpo software suites for EOS imaging system and CT-scanner, respectively. RESULTS: The EOS imaging system reduces radiation exposure 4 to 8 times compared to the CT-scanner. The entrance skin doses were 74% (p-values <0.01) higher with the CT-scanner than with the EOS system. In the out of field region, the measured doses of the EOS system were reduced by 80% (p-values <0.02). Monte Carlo calculations confirmed that effective doses to organs are less accentuated for EOS than for CT pelvimetry. CONCLUSIONS: The EOS system is less irradiating than the CT exam. The out-of-field dose which is significant, is lower in the EOS than in the CT-scanner and could be reduced even further by optimizing the time used for image acquisition.
Authors: M Lallemant; T Ceri; Y Offringa; S Aubry; A Bourtembourg; D Riethmuller; R Ramanah; P Guerby; N Mottet Journal: Arch Gynecol Obstet Date: 2021-03-31 Impact factor: 2.344