Andrea Guasti1, Sara Leonini2, Eugenio Bertelli3, Roberta Baldi4, Paola Gennari5, Samuele Cioni5, Ignazio Maria Vallone5, Daniele Giuseppe Romano5, Tommaso Casseri6, Leonardo Guerrini7, Annunziata Elena La Rocca7, Paolo Gambini Della Scala5, Sonia De Francesco8, Theodora Hadjistilianou8, Sandra Bracco5. 1. Department of Medical Physics, Azienda USL Toscana sud est, Siena, Italy. 2. Unit of Neuroimaging and Neurointervention, Azienda Ospedaliera Universitaria Senese, Siena, Italy. s_leonini@yahoo.it. 3. Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy. 4. Department of Diagnostic Imaging, Azienda Ospedaliera Universitaria Senese, Siena, Italy. 5. Unit of Neuroimaging and Neurointervention, Azienda Ospedaliera Universitaria Senese, Siena, Italy. 6. Department of Medical, Surgical and Neuro Sciences, Diagnostic Imaging, University of Siena, Siena, Italy. 7. Department of Medical Physics, Azienda Ospedaliera Universitaria Senese, Siena, Italy. 8. Department of Medicine, Surgery and Neuroscience, Unit of Ophthalmology, Azienda Ospedaliera Universitaria Senese, Siena, Italy.
Abstract
PURPOSE: Purposes are (1) to measure main radiation parameters and (2) to propose a method to estimate the absorbed doses of internal organs starting from DAP values. Measuring the exposition of internal organs by repeated irradiations on an anthropomorphic phantom with the same settings used in vivo, we could establish correlations between (1) DAP and the dose recorded by a dosimeter placed along the X-ray beam entrance pathway; (2) the dose recorded by the same dosimeter and the absorbed dose in internal organs. METHODS: Forty-four consecutive patients (16 males, 28 females) (mean age 35.4 months) treated at our institution with IAC (216 procedures: 196 via the ICA and 20 into branches of the ECA) were included in this prospective study. IAC was divided into 5 phases. Fluoroscopic time, DAP, and ESD were measured. RESULTS: The mean DAP was 595 ± 445 cGy cm2 and the mean fluoroscopic time was 540 ± 403 s. ESD was on average 9.59 mGy (range 0.8-165 mGy). The absorbed dose was lower than 12.1 mGy in the left retina (the more exposed organ) in 75% of single treatments and lower than 25 mGy in 95% of treatments. In the cases of 3 and 6 sessions, the left retina of 75% of patients absorbed respectively less than 36.3 and 72.7 mGy, whereas the left retina of 95% of patients received less than 75.2 and 150.4 mGy. Other organs were less exposed. CONCLUSION: This paper describes a method of absorbed dose estimation providing ranges used clinically in a single practice and the basis for further prospective studies.
PURPOSE: Purposes are (1) to measure main radiation parameters and (2) to propose a method to estimate the absorbed doses of internal organs starting from DAP values. Measuring the exposition of internal organs by repeated irradiations on an anthropomorphic phantom with the same settings used in vivo, we could establish correlations between (1) DAP and the dose recorded by a dosimeter placed along the X-ray beam entrance pathway; (2) the dose recorded by the same dosimeter and the absorbed dose in internal organs. METHODS: Forty-four consecutive patients (16 males, 28 females) (mean age 35.4 months) treated at our institution with IAC (216 procedures: 196 via the ICA and 20 into branches of the ECA) were included in this prospective study. IAC was divided into 5 phases. Fluoroscopic time, DAP, and ESD were measured. RESULTS: The mean DAP was 595 ± 445 cGy cm2 and the mean fluoroscopic time was 540 ± 403 s. ESD was on average 9.59 mGy (range 0.8-165 mGy). The absorbed dose was lower than 12.1 mGy in the left retina (the more exposed organ) in 75% of single treatments and lower than 25 mGy in 95% of treatments. In the cases of 3 and 6 sessions, the left retina of 75% of patients absorbed respectively less than 36.3 and 72.7 mGy, whereas the left retina of 95% of patients received less than 75.2 and 150.4 mGy. Other organs were less exposed. CONCLUSION: This paper describes a method of absorbed dose estimation providing ranges used clinically in a single practice and the basis for further prospective studies.