In vivo dosimetry with optically stimulated dosimeters and RTQA2 radiochromic film for intraoperative radiotherapy of the breast

Abstract

OSLDs produce results with an uncertainty comparable to other dosimeters near the surface of the applicator but the uncertainty increases to an unacceptably high level with distance from the applicator. RTQA2 radiochromic film is shown to be accurate both at the surface of the applicator and at distances of 1-2 cm.

A national dosimetry audit of intraoperative radiotherapy

“…Therefore, even if the output measurement is very close to expected, there will be an underdose of around 10% to other areas of the treatment volume. This is consistent with recent in vivo measurements using GAFCHROMIC film around the inside of the tumour cavity, which found mean differences compared with planned values of 212% [22] and 217% [23] for the 4.5-cm-diameter applicator.…”

Monte Carlo based investigations of electron contamination from telecobalt unit head in build up region and its impact on surface dose

“…Gafchromic EBT2 and EBT3 films were used for in vivo dosimetry of 6 MV photon and 9 MeV electron beams and found suitable for in vivo dosimetry with good accuracy [17]. Though RTQA2 films are being used for quality assurance such as light / radiation field congruence tests, researchers [18,19,20] have used RTQA2 for absolute and relative dosimetry applications. Radiochromic RTQA2 film were used by Price et al [18] for the absolute in vivo dosimetry with 50 kVp intraoperative radiotherapy source and found variation of ±8% of delivered dose with RTQA2 film measurement.…”

“…Though RTQA2 films are being used for quality assurance such as light / radiation field congruence tests, researchers [18,19,20] have used RTQA2 for absolute and relative dosimetry applications. Radiochromic RTQA2 film were used by Price et al [18] for the absolute in vivo dosimetry with 50 kVp intraoperative radiotherapy source and found variation of ±8% of delivered dose with RTQA2 film measurement. Peng et al [19] used RTQA2 films for the measurement of patient specific quality assurance as a 2D relative dosimeter using plan based calibration method and found suitable for this type of measurements.…”

“…From literature survey, it is clear that extensive research has been carried out to measure surface dose of telecobalt unit [3,[5][6][7][8][9][10][25][26][27] as well as medical linear accelerator [1,11,12,21,22,[28][29][30]. The researchers have used different measurement techniques such as extrapolation chamber [5], parallel plate chamber [5,6,7], TLD [5,7,8], Gafchromic films [13][14][15][16][17][18][19][20][21][22], MOSFET [31,32]. The Gafchromic EBT3 films have also used for measurement of dose in small X-ray field size [33].…”

Prediction of skin dose in low‐kV intraoperative radiotherapy using machine learning models trained on results of in vivo dosimetry

“…As skin dose can be critical for IORT, many studies focused on developing techniques to measure in vivo dose to the skin using different types of dosimeter, including radiochromic films, Thermoluminescent dosimeters (TLDs), and optically stimulated luminescent dosimeters (OSLDs) . In vivo measurements of dose are also essential as they help identifying systematic and random errors in treatment delivery .…”