Performance of optically stimulated luminescence Al2O3 dosimeter for low doses of diagnostic energy X-rays

Entrance Skin Dose (ESD) and Bucky Table Induced Backscattered Dose (BTI-BSD) in Abdominal Radiography With nanoDot Optically Stimulated Luminescence Dosimeter (OSLD)

In radiography, inconsistencies in patients' measured entrance skin dose (ESD) exist. There is no published research on the bucky table induced backscattered radiation dose (BTI-BSD). Thus, we aimed to ascertain ESD, calculate the BTI-BSD in abdominal radiography with a nanoDot OSLD, and compare the ESD results with the published data. A Kyoto Kagaku PBU-50 phantom (Kyoto, Japan) in an antero-posterior supine position was exposed, selecting a protocol used for abdominal radiography. The central ray of x-ray beam was pointed at the surface of abdomen at the navel, where a nanoDot dosimeter was placed to measure ESD. For the BTI-BSD, exit dose (ED) was determined by placing a second dosimeter on the exact opposite side (backside) of the phantom from the dosimeter used to determine (ESD) with and without bucky table at identical exposure parameters. The BTI-BSD was calculated as the difference between ED with and without bucky table. The ESD, ED, and BTI-BSD were measured in milligray (mGy). ESD mean values with and without bucky table were 1.97 mGy and 1.84 mGy, whereas ED values were 0.062 mGy and 0.052 mGy, respectively. Results show 2-26% lower ESD values with nanoDot OSLD. The BTI-BSD mean value was found to be approximately 0.01 mGy. A local dose reference level (LDRL) can be established using ESD data to safeguard patients from unnecessary radiation. In addition, to minimize the risk of BTI-BSD in patients in radiography, the search for the use or fabrication of a new, lower atomic number material for the bucky table is suggested.

Comparison of experimental and simulated responses of TL and OSL dosimeters in poly-energetic and multi-directional photon radiation fields

The aim of this paper is to examine the energy and angular responses of thermoluminescent (LiF:Mg,Ti and LiF:Mg,Cu,P) and optically stimulated luminescent (Al2O3:C) dosimeters with experimental measurements and Monte Carlo simulations. Nine radiation qualities, with mean energies ranging from 33 keV to 1.25 MeV, and five angles of incidence, between 0? and 80?, were used to conduct this analysis. The IEC 62387:2020 international radiation protection standard was used as the dosimeter response measure of quality. The experimental and simulated data exhibit that the dosimeter responses meet the standard's criteria, with certain exceptions on lower energies.

ESTIMATION OF Hp(3) TO THE EYE LENS OF INTERVENTIONAL RADIOLOGISTS-RELATION BETWEEN THE EYE LENS DOSE AND RADIOLOGIST'S HEIGHT

The aim of the study was to estimate occupational radiation dose to the eye lens of radiologists and the dose reduction ratio of lead glasses during interventional radiology. Three interventional radiologists monitored Hp(3) using small-type optically stimulated luminescence dosemeters attached to the left inside and outside of the lead glasses with 0.07-mmPb [Hp(3)eye]. Hp(10) and Hp(0.07) were monitored, respectively, by attaching the personal dosemeter to the lead neck collar above the lead apron. The median Hp(3)eye with lead glasses and the median dose reduction ratio of lead glasses for the three radiologists were 8.02 mSv/y and 57.7%, respectively. The median Hp(3)eye without lead glasses [Hp(3)eye-w/o] for the three radiologists was 18.6 mSv/y, but Hp(3)eye-w/o for one of the radiologists was 24.1 mSv/y. Monitoring occupational radiation dose to the eye lens is important because interventional radiologists are at risk of exceeding the new dose limit.

Response of TL and OSL passive personal dosimetry systems in poly-energetic and multi-directional photon radiation fields

The aim of this paper is to examine the energy and angular responses of thermoluminescent dosimeters containing either MTS-N (LiF:Mg,Ti) or MCP-N (LiF:Mg,Cu,P) detector materials, and of the InLight optically stimulated luminescent dosimeters containing Al₂O₃:C detectors. Ten radiation qualities, with mean energies ranging from 24 keV to 1.25 MeV, and five angles of incidence, between 0° and 80°, were used for this purpose. The dosimeter response measure of quality were the IEC 62387 requirements. The experimental results show that the MTS-N-based and the InLight dosimeters performed in line with the standard's criteria. On the other hand, the MCP-N-based dosimeters exhibited a pronounced under-response around the energy of 120 keV, which resulted in deviations from the standard's conditions for both the energy and angular responses.

Optically stimulated Al2O3:C luminescence dosimeters for teletherapy: Hp(10) performance evaluation

The performance of optically stimulated luminescence dosimeters (OSLDs, Al₂O₃:C) was evaluated in terms of the operational quantity of H_P(10) in Co-60 external beam teletherapy unit. The reproducibility, signal depletion, and dose linearity of each dosimeter was investigated. For ten repeated readouts, each dosimeter exposed to 50mSv was found to be reproducible below 1.9 ± 3% from the mean value, indicating good reader stability. Meanwhile, an average signal reduction of 0.5% per readout was found. The dose response revealed a good linearity within the dose range of 5-50mSv having nearly perfect regression line with R² equals 0.9992. The accuracy of the measured doses were evaluated in terms of operational quantity H_P(10), wherein the trumpet curve method was used respecting the 1990 International Commission on Radiological Protection (ICRP) standard. The accuracy of the overall measurements from all dosimeters was discerned to be within the trumpet curve and devoid of outlier. It is established that the achieved OSL Al₂O₃:C dosimeters are greatly reliable for equivalent dose assessment.