Program Information
Preliminary Analysis of AAPM TG 251 - Survey of Pediatric Fluoroscopic Exposure Rates
U Mahmood1*, S Brady2 , S McKenney3 , C Willis4 , V Patel5 , I Bercha6 , N Kasraie7 , M Aljallad8 , C Dodge9 , D Kim10 , K Buckley11 , T Cummings12 , A Kuhls-Gilcrist13 , D Jordan14 , L Dauer15 , K Strauss16 , (1) Memorial Sloan Kettering Cancer Center, Lynbrook, NY, (2) St. Jude Children's Research Hospital, Memphis, TN, (3) Children's National Medical Center, Washington, DC, (4) MD Anderson Cancer Center, Bellaire, TX, (5) Upstate Medical Physics, W Henrietta, NY, (6) Children's Hospital Colorado, Aurora, CO, (7) Children's Mercy Hospitals and Clinics, Kansas City, MO, (8) Children's Mercy Hospitals and Clinics, York, PA, (9) Texas Children's Hospital, Houston, TX, (10) Boston Children's Hospital, Boston, MA, (11) Children's Hospital, Boston, MA, (12) NYU Langone Medical Center, New York, NY, (13) Toshiba America Medical Systems, Inc, Tustin, CA, (14) University Hospitals Cleveland Medical Center, Shaker Heights, OH, (15) Memorial Sloan-Kettering Cancer Ctr, New York, NY, (16) Children's Hospital Medical Center, Cincinnati, OH
Presentations
SU-E-702-1 (Sunday, July 30, 2017) 1:00 PM - 1:55 PM Room: 702
Purpose: To report preliminary findings in radiation output and fluoroscopic acquisition configurations for pediatric patients at pediatric, academic, and community facilities within the USA.
Methods: Radiation output data and the configurations of mobile c-arms, general fluoroscopic (RF), and interventional (IR) units [general, cardiac catheterization, and electrophysiology (EP)] were collected using a standardized protocol. Blocks of 25x25 cm cross-section PMMA ranging in thicknesses from 5 to 25 cm were used to simulate pediatric abdominal attenuation. Depending on design, each fluoroscopic unit was evaluated in continuous and/or pulsed modes. When possible, grids were removed for attenuator thicknesses <10 cm. Solid state and ionization dosimeters were used. Exam parameters such as: kV, root-mean-squared (RMS) mA, and added filtration were recorded. Entrance air kerma rate (AKR) and pulse width were measured as a function of thickness. Relationships between the AKR and the acquisition parameters versus thickness were explored.
Results: To date, data has been collected from a total of 70 fluoroscopic units (32 mobile c-arms, 10 RF units, 28 general IR, cardiac cath or EP labs). The median (25th, 75th percentiles) AKR for 5, 10, 15, 20, and 25 cm of PMMA for all units and fluoroscopic modes was 0.49 (0.33,1.1), 1.2 (0.79, 2.8), 3.8 (2.0, 6.5), 9.7 (4.2, 15), and 22 (8.6,29) mGy/min. Corresponding tube voltages 58 (55,60), 65 (60, 68), 71 (69,75), 81 (70,86), and 94 (77, 102) kVp; and RMS currents 0.98 (0.64, 1.3), 1.9 (1.3, 2.3), 2.8 (2.2, 6.1), 3.9 (3.2, 15), and 4.9 (4.2, 19) RMS-mA. Pulse widths reported only for IR units were: 3.0 (2.6, 3.4), 4.1 (3.3, 4.3), 4.9 (3.9, 6.3), 8.7 (4.6, 9.7) and 8.6 (5.3, 12) ms.
Conclusion: The wide variation in kV, RMS-mA, pulse widths, and other acquisition settings suggest pediatric-specific configurations should be established during acceptance testing to improve pediatric radiation exposure.
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