Radiation Dose Monitoring Research Articles

Left radial vs right femoral: comparison between arterial accesses in c-TACE procedures in terms of operator radiations exposure and patient comfort.

This multicenter prospective study aims to compare transradial access versus transfemoral access in conventional transarterial chemoembolization (c-TACE) procedures, focusing on operators radiations exposure, patients comfort, technical success and vascular access complications. Patients were affected by hepatocellularcarcinoma (HCC) in intermediate stage or previous stages unfit for ablation and/or surgery; they were randomized into two groups according to arterial access site (Group F: right femoral access in standard position; Group R: radial access with left arm abduced 90°). Overall fluoroscopy time was recorded. Eight thermoluminescence dosimeters were positioned immediately before each procedure to monitor radiation doses. Technical success was intended as complete HCC nodules lipiodolization at final plain cone-beam CT. Group F included 23 patients, while group R 19. Mean fluoroscopy time was lower in group F but difference was not statistically significant (p-value > 0.05). In terms of operators radiations exposure, no significant differences were found (p-value > 0.05). Technical success was obtained in 81.5% in group F and 84.8% in group R, without significant differences (p-value > 0.05). Patients discomfort was significantly (p-value < 0.05) higher in group F. Concerning minor complications, no statistical differences were appreciated (p-value > 0.05); no major complications occurred. In this study, no statistical differences were observed in terms of operators radiations exposure, fluoroscopy time and technical success during c-TACE performed with left radial access compared to right femoral access; patients comfort was significantly better with radial access. These data should lead interventional radiologists to favor radial access in c-TACE interventions.

Gd3+ doped Na2O-CaO-P2O5-B2O3-ZrO2 glass ceramics for γ-ray radiation dose detection

In this study, Gd3+-doped NCPBZ glass-ceramics were prepared using melt-quenching technique, and their radiation dose performance was investigated. By varying the concentration of Gd3+ ions, we found that the sample with 0.5 mol% concentration exhibited the strongest luminescence and the best optically stimulated luminescence (OSL) intensity. Therefore, further OSL related tests were conducted on samples with this concentration under different doses. The results showed that the continuous wave OSL dose response fitting value of the sample in the range of 0.1–1000 Gy was m = 0.928, which is close to 1, while R2 was 0.9992 in the range of 50–1000 Gy, indicating better linearity. Meanwhile, the relative standard deviation of the OSL intensity for the sample's ten-cycle tests was 1.5%. The Gd3+-doped NaCaPO4 microcrystalline glass studied here is expected to have broad application prospects in wide-range linear radiation dose monitoring.

Assessing Effective Doses and Proposing DRLs for Pediatric CT Procedures in Madinah (Single Hospital), Saudi Arabia

This study aims to assess effective radiation doses (EDs) for pediatric computed tomography (CT) procedures in Madinah (single hospital), Saudi Arabia, and propose diagnostic reference levels (DRLs) for these procedures. This retrospective study collected data from 600 pediatric patients who underwent five CT procedures. The data were categorized by the type of CT procedure and the age of the patients. EDs and proposed DRLs for the pediatric CT procedures were computed. The highest EDs were found for abdominal (6.3 mSv) and head (4.8 mSv) CT procedures in pediatric patients aged &lt;1 year. DRLs of the CTDIvol and DLP for abdominal and head CT procedures in pediatric patients aged &lt;1 year were 4.2 mGy, 94 mGy.cm and 25 mGy, 414 mGy.cm, respectively. Chest EDs had the lowest EDs among all pediatric CT procedures, with EDs of 1.93, 1.51, 1.91, and 2.05 mSv in patients aged &lt;1, 1 ≤ to &lt; 5, 5 ≤ to &lt; 10, and 10 ≤ to ≤ 15 years, respectively. It can be concluded that optimization is required for abdominal and head CT procedures in pediatric patients aged &lt;1 year. Frequent updates on ED and DRL calculations will help monitor radiation doses and minimize radiation risks for patients undergoing these procedures.

Optimizing neurointerventional procedures: an algorithm for embolization coil detection and automated collimation to enable dose reduction.

Monitoring radiation dose and time parameters during radiological interventions is crucial, especially in neurointerventional procedures, such as aneurysm treatment with embolization coils. The algorithm presented detects the presence of these embolization coils in medical images. It establishes a bounding box as a reference for automated collimation, with the primary objective being to enhance the efficiency and safety of neurointerventional procedures by actively optimizing image quality while minimizing patient dose. Two distinct methodologies are evaluated in our study. The first involves deep learning, employing the Faster R-CNN model with a ResNet-50 FPN as a backbone and a RetinaNet model. The second method utilizes a classical blob detection approach, serving as a benchmark for comparison. We performed a fivefold cross-validation, and our top-performing model achieved mean mAP@75 of 0.84 across all folds on validation data and mean mAP@75 of 0.94 on independent test data. Since we use an upscaled bounding box, achieving 100% overlap between ground truth and prediction is not necessary. To highlight the real-world applications of our algorithm, we conducted a simulation featuring a coil constructed from an alloy wire, effectively showcasing the implementation of automatic collimation. This resulted in a notable reduction in the dose area product, signifying the reduction of stochastic risks for both patients and medical staff by minimizing scatter radiation. Additionally, our algorithm assists in avoiding extreme brightness or darkness in X-ray angiography images during narrow collimation, ultimately streamlining the collimation process for physicians. To our knowledge, this marks the initial attempt at an approach successfully detecting embolization coils, showcasing the extended applications of integrating detection results into the X-ray angiography system. The method we present has the potential for broader application, allowing its extension to detect other medical objects utilized in interventional procedures.

Co-designing of a prototype mobile application for fetal radiation dose monitoring among pregnant radiographers using a design thinking approach.

This study aimed to develop a prototype mobile application to enhance fetal dosimetry among pregnant radiographers in #### through a design thinking approach. Eleven participants were recruited to engage in a participatory design workshop, which encompassed five stages: Empathise, Ideate, Define, Prototype and Test. The participants were divided into two teams. Qualitative datasets from the workshop included field notes and FIGMA screens. The data were analysed through thematic analysis, from which three major themes emerged: (1) Unsafe working environments for pregnant radiographers, (2) The need for enhanced fetal radiation dose monitoring by pregnant radiographers as an occupational health and safety requirement, and (3) Co-designing of the prototype mobile application, PregiDose. The participants contributed towards a prototype mobile application which addressed challenges experienced in the real-life setting. Hence, the prototype can be used as an effective framework by which to guide the development of the final artefact.

Quantitative assessment of occupational radiation exposure in CT: a comparative study using two radiation survey meters for year-long dose monitoring of staff

Introduction: Computed Tomography (CT) is crucial in medical imaging but exposes healthcare workers to ionizing radiation. It is essential to quantify and mitigate occupational radiation exposure. This study provides a comprehensive quantitative analysis of CT settings, using two radiation survey meters, over a year-long monitoring period. Methodology: Healthcare workers operating CT scanners were included. Two radiation survey meters, Meter A (GMC-300E, uSv/h) and Meter B (RAR R311516, uSv/h), were used concurrently for continuous measurement and recording of radiation doses. Statistical analysis compared data from both meters and assessed compliance with regulatory limits and quality assurance standards. Results: The study demonstrated excellent consistency in dose measurements between Meter A and Meter B throughout the year, with no statistically significant discrepancies (p≤; 0.05). Cumulative radiation doses of staff remained within legal limits, indicating the efficacy of current safety measures. Conclusion: The study highlights the reliability of Meter A and Meter B for measuring occupational radiation exposure in CT settings. The convergence of results emphasizes their suitability for healthcare settings requiring precise radiation dose monitoring, enhancing radiation safety in CT scanning and protecting healthcare personnel from ionizing radiation exposure.

Luminescence properties of Ce and Be-doped CaAl12O19 for dosimetric and light-emitting applications

In this study, we reported the sol-gel production of cerium (Ce) and beryllium (Be)-doped calcium aluminate (CaAl12O19) and its luminescence properties for optically stimulated luminescence (OSL) dosimetry and light-emitting applications. Structural, morphological and elemental characteristics of the samples were examined by x-ray diffraction (XRD), Scanning electron microscope (SEM)/energy dispersive spectrum (EDS), x-ray fluorescence (XRF) and Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) techniques. The maximum OSL intensity was achieved with 0.5 and 2% mol concentrations of Ce and Be dopants, respectively. We investigated the OSL and thermoluminescence (TL) properties of Ce and Be-doped CaAl12O19 by measuring energy storage for 24 h, dose-response in the range of 0.1 and 20 Gy, and reusability of the samples for 15 cycles. Photometric properties of the phosphors were investigated by evaluation of CIE chromaticity coordinate (x, y), CCT, and colour purity using its corresponding photoluminescence (PL) emission spectra. We also applied computerized glow curve deconvolution (CGCD), various heating rate methods, and the Tm-Tstop procedure to determine the trap localizations associated with the TL glow curve. The results of this study point out that CaAl12O19 crystals have the potential to be used as OSL dosimetry when appropriate dopants are used. This study may offer new possibilities in radiation dose detection and monitoring.

Implementasi Pemanfaatan Sumber Radiasi Pengion pada Ruang CT Scan ditinjau berdasarkan Peraturan BAPETEN No. 4 tahun 2020 di Instalasi Radiologi Rumah Sakit type B di Wilayah Kabupaten Sumedang

Background: Occupational safety and health (OSH) management is the main factor in hospital services, which aims to control and minimize potential dangers due to radiation. One of the evaluations used is the implementation of OSH management requirements based on the Republic of Indonesia Ministry of Health Regulation No. 1014 of 2008 and Bapeten regulation no. 4 of 2020. The aim of this research was to determine the extent of implementation of OSH management in terms of completeness of management requirements, radiation protection, room design and personal protective equipment (PPE) implemented in Radiology Department in hospital type B, Sumedang Regency.Methods: This research was a descriptive qualitative by conducting direct observations, interviews and documentation.Results: The results of the research on the design of the room without ventilation outside the CT Scan room, this aims to minimize the dose of scattered radiation that comes out, decentralization and good air circulation, has warning signs and directions for radiation danger areas, the radiation protection equipment is quite complete. Implementation of radiation management has been carried out, but not completely, there is no health monitoring at the end of the work period and upon termination of work. Radiation safety verification has been carried out periodically, quality control is only carried out externally, so it does not meet standards, internal quality control cannot be carried out because there is no survey meter.Conclusions: This research was conducted in Radiology Department room in August 2023, the results showed that in the CT Scan room there was no air ventilation, there was radiation dose monitoring for staff, overall, Radiology Installation hospital type B in Sumedang Regency area had implemented occupational safety and health.

Proposed Diagnostic Reference Levels in the Missouri/Southern Illinois Region Associated with Cone-beam Computed Tomography Use in Endodontics

IntroductionDiagnostic reference levels (DRLs) are intended to improve patient safety and ensure that patient ionizing radiation doses are as low as reasonably achievable. The purpose of this dosimetry study was to establish regional DRL levels for cone-beam computed tomography (CBCT) imaging for specialty endodontics. Another aim was to compare phantom-measured ionizing radiation dose index 1 (DI1) index doses to the manufacturer-provided dose area product (DAP) radiation output values for each of the CBCT machines studied, to ascertain their degree of correlation. DAP refers to the dose area product, a measure of radiation dose monitoring which represents the dose within the beam times the area within the beam at that position. MethodsA thimble ionization chamber and polymethyl methacrylate phantom were used to obtain DI1 values using the SEDENTEXTCT method from 21 different CBCT units. DRLs were calculated based on the 75th percentile (third quartile) of the median output values. ResultsThe proposed DRL from the CBCT units surveyed has a DAP value of 838 mGy cm2 and a DI1 value of 3.924 mGy. DAP versus DI1 values of 500.6 mGy cm2 versus 2.006 mGy, and 838 mGy cm2 versus 3.906 mGy represented the third quartile of the median values for the 4-cm × 4-cm and 5-cm × 5-cm field of views (FOVs), respectively. ConclusionsThe DI1 and DAP values strongly correlated when 3 outlier CBCT machines (J Morita Veraview X800) using a novel 360° (full rotation) acquisition mode were excluded. The importance of selectable exposure parameters as directly related to ionizing radiation output is illustrated among the CBCT units surveyed. Although the actual FOV that is selected is ultimately dictated by the specific clinical requirements, a 4-cm × 4-cm FOV is recommended for specialist endodontics practice, whenever clinically practical, based on the decreased ionizing radiation output, as compared to that from a 5-cm × 5-cm FOV.

Clinical benchmarking of a commercial software for skin dose estimation in cardiac, abdominal, and neurology interventional procedures.

Radiation exposure from interventional radiology (IR) could lead to potential risk of skin injury in patients. Several dose monitoring software like radiation dose monitor (RDM) were developed to estimate the patient skin dose (PSD) distribution in IR. This study benchmarked the accuracy of RDM software in estimating PSD as compared to GafChromic film baseline in-vivo measurements on patients during cardiac, abdominal, and neurology IR procedures. The prospective study conducted in four IR departments included 81 IR procedures (25 cardiac, 31 abdominal, and 25 neurology procedures) on three angiographic systems. PSD and field geometry were measured by placing GafChromic film under the patient's back. Statistical analyses were performed to compare the software estimation and film measurement results in terms of PSD and geometric accuracy. Median values of measured/calculated PSD were 1140/1005, 591/655.9, and 538/409.7mGy for neurology, cardiac, and abdominal procedures, respectively. For all angiographic systems, the median (InterQuartile Range, IQR) difference between calculated and measured PSD was -10.2% (-21.8%-5.7%) for neurology, -4.5% (-19.5%-15.5%) for cardiac, and -21.9% (-38.7%--3.6%) for abdominal IR procedures. These differences were not significant for all procedures (p>0.05). Discrepancies increased up to -82% in lower dose regions where the measurement uncertainties are higher. Regarding the geometric accuracy, RDM correctly reproduced the skin dose map and estimated PSD area dimensions closely matched those registered on films with a median (IQR) difference of 0cm (-1-0.8cm). RDM is proved to be a useful solution for the estimation of PSD and skin dose distribution during abdominal, cardiac and neurology IR procedures despite a geometry phantom which is not specific to the latter type of IR procedures.

Research on indoor environmental monitoring technology and radiation intensity control method for industrial X-ray flaw detection

Abstract With the development of China’s economy, the application of industrial radiation flaw detection technology is becoming more and more widespread, and the radiation monitoring and protection of flaw detection work has become an important topic in the field of radiation safety and protection. This paper uses pyroelectric technology to track X-ray radiation levels in the environment. It also chooses the scale curve method for calibrating the pyroelectric dosimeter and figures out the scale factor at the same time. The neutron and photon dimensions are used to evaluate the personal dose equivalent. The applicable range of pyroelectric dosimeters is calculated and the method is applied for radiation dose monitoring in industrial X-ray flaw detection rooms. Concrete wall shielding is used to determine the design parameters of the flaw detection room and the location of the distribution points to improve the shielding capacity of the flaw detection room and control the radiation intensity. The monitoring value of the operation position of the flaw detection room of Leshan Leboiler Enterprises in 2018 was 258.2, which was 73 higher than that of 2019. The results of the on-site monitoring of the absorbed dose rate of the ambient air in the flaw detection room showed that the average absorbed rate ranged from 0.015 to 0.546 μSv/h, which was lower than the standard of 2.5 μSv/h, and the shielding capacity of the flaw detection room was better, and the intensity of the radiation could be effectively controlled.

Annual radiation dose monitoring for catheterization laboratory operators

Monitoring the occupational radiation exposure to the operators is important from the viewpoint of radiation protection and safety. The main purpose of this study is to measure and analyze the annual radiation occupational dose to the operators in a unit of mSv in the Catheterization Laboratory (CL) at King Abdul-Aziz University Hospital (KAUH). This study measured and determined the annual effective dose to the CL operators for Twenty-Three operators at KAUH. Based on the responsibilities and position, the monitored operators were classified into different categories: Staff/Doctors, Nurses, and Technicians. The annual occupational doses were measured using Thermoluminescence dosimetry (TLD-100 (LiF: Mg, Ti)) placed at the Thyroid protective collar from the body to measure the individual dose. The calibration procedures and measurements in this study were carried out at the King Abdul-Aziz University Training and Prevention Center of the University of Radiation. The average annual dose to the CL was found to be 0.74, 1.10, 1.13, 0.65, 0.18, and 1.0 mSv for Consultants, Technicians, Nurses, Doctors, Registrar Cardiology, and Trainees respectively. More than 91% of the operators in the CL received radiation doses of less than 2 mSv. High awareness and skills are the reasons for obtaining a very low annual occupational dose in the department of CL at KAUH. The maximum value for the effective dose delivered to the operator is 2.29 mSv, which is much lower than the international dose limit (20 mSv/y) given by the International Commission of Radiological Protection (ICRP).

Radiation exposure in spine surgeries

Radiation exposure is a significant concern in spine surgeries due to the extensive use of fluoroscopic imaging. This review aims to evaluate the risks, consequences, and prevention strategies associated with radiation exposure in spine surgeries. The risks of radiation exposure include potential biological damage to patients and surgical staff, such as skin burns, cataracts, and an increased risk of developing cancer. The consequences of radiation exposure can have long-term health implications and may result in substantial healthcare costs. To mitigate the risks, various prevention strategies are recommended. These include optimizing the use of fluoroscopy by adopting low-dose imaging techniques, minimizing the duration of exposure, and ensuring proper shielding of personnel. Additionally, the use of alternative imaging modalities, such as intraoperative three-dimensional (3D) navigation systems, can reduce reliance on fluoroscopy and subsequently decrease radiation exposure. Furthermore, implementing a culture of radiation safety through education, training, and awareness programs is crucial. This involves educating surgeons, nurses, and other healthcare professionals about the potential risks, proper use of equipment, and radiation protection measures. Strict adherence to radiation safety guidelines and continuous monitoring of radiation doses are essential to ensure the well-being of both patients and healthcare providers. In short, radiation exposure in spine surgeries poses significant risks and potential consequences. However, with the adoption of appropriate prevention strategies, such as optimizing imaging techniques, implementing alternative modalities, and fostering a culture of radiation safety, the potential risks can be mitigated. By prioritizing radiation safety, healthcare facilities can provide better outcomes for patients and minimize the long-term health implications associated with radiation exposure in spine surgeries.

Better safe than so ray: national survey of radiation protection amongst interventional radiology trainees in the United Kingdom.

To establish the provision and use of radiation personal protective equipment (PPE) and dosimetry amongst UK interventional radiology (IR) trainees and highlight areas of improvement in order to enhance the radiation safety. A survey questionnaire was designed by members of the British Society of Interventional Radiology (BSIR) trainee committee via survey monkey and distributed to UK IR trainees via the BSIR membership mailing list, local representatives and Twitter. The survey was open from 04/01/2021 to 20/02/2021. Only IR trainees in years ST4 and above were included. Of the 73 respondents, 62 qualified for analysis. Respondents (81% male) spent a median of 5.5 sessions (half day list) per week in the angiography suite and 58% (n=36) had difficulty finding appropriately sized lead aprons at least once a week. Overall 53% (n=33) had concerns about their radiation PPE. Furthermore 56% of trainees (n=35) experienced back pain among other symptoms attributed to wearing the lead aprons available to them. 77% (n=48) regularly wore lead glasses. For trainees requiring prescription glasses (n=22) overfit goggles were provided however 17 (77%) of these trainees felt the goggles compromised their ability to perform the procedure. Eye and finger dosimeters were used by 50% and 52% of respondents respectively. Compliance with body dosimetry was 99%. Provision of radiation PPE and dose monitoring for IR trainees is suboptimal, particularly access to adequate eye protection or suitably fitting leads. Based on the findings of this survey, recommendations have been made to promote the safety and radiation awareness of IR trainees. Radiation protection practices for IR trainees nationally are poor. Provision of suitable eye protection and well fitting lead body protection is low.

Machine learning to predict environmental dose rates from a radionuclide therapy service — a proof of concept study

The Ionising Radiation Regulations 2017 requires prior risk assessment calculations and regular environmental monitoring of radiation doses. However, the accuracy of prior risk assessments is limited by assumptions and monitoring only provides retrospective evaluation. This is particularly challenging in nuclear medicine for areas surrounding radionuclide therapy patient bathroom wastewater pipework. Machine learning (ML) is a technique that could be applied to patient booking records to predict environmental radiation dose rates in these areas to aid prospective risk assessment calculations, which this proof-of-concept work investigates. 540 days of a dosimeters historical daily average dose rate measurements and the corresponding period of department therapy booking records were used to train six different ML models. Predicted versus measured daily average dose rates for the following 60 days were analysed to assess and compare model performance. A wide range in prediction errors was observed across models. The gradient boosting regressor produced the best accuracy (root mean squared error = 1.10 µSv.hr−1, mean absolute error = 0.87 µSv.hr−1, mean absolute percentage error = 35% and maximum error = 3.26 µSv.hr−1) and goodness of fit (R 2 = 0.411). Methods to improve model performance and other scenarios where this approach could prove more accurate were identified. This work demonstrates that ML can predict temporal fluctuations in environmental radiation dose rates in the areas surrounding radionuclide therapy wastewater pipework and indicates that it has the potential to play a role in improving legislative compliance, the accuracy of radiation safety and use of staff time and resources.

Patient exposure during videofluoroscopic swallowing studies performed by speech-language pathologists.

Videofluoroscopic swallowing studies (VFSSs) are fluoroscopic examinations performed by speech and language pathologists (SLPs), for the evaluation of the oral and pharyngeal phases of swallowing, in patients who are diagnosed with symptoms like dysphagia and speech impairment. The study was focused on the evaluation of the patient doses from VFSS performed at Hamad Medical Corporation hospitals. Data on the patient exposure and examination parameters were extracted from the Radiation Dose Monitoring system, statistically analysed and compared with literature. For adult patients, the mean (median) values for fluoroscopy time and kerma-air product were 2.8 (2.7) min and 181 (144) cGycm2, respectively. For children, the respective mean (median) values were 2.6 (2.4) min and 15.3 (9.2) cGycm2. The results of the study indicate that the VFSS are performed by well-trained health professionals, and as a result, image quality sufficient for a confident diagnosis is obtained at relatively low dose levels.

MANAGEMENT OF LOWER LIMB TRAUMA IN PREGNANCY

Objective: Lower limb fracture in pregnancy is a rare complication. Still, there is limited literature available on the management of these fractures, and perioperative obstetric and orthopedic management of these fractures is largely unclear. Trauma during pregnancy is a common cause of non-obstetrical maternal death and a significant public health burden. This study reviews the common causes of lower limb trauma during pregnancy, morbidity, mortality, and provides a management approach to pregnant patients with lower limb trauma. Methods: A prospective analysis was conducted in the orthopedics department of Government Medical College, Patiala from 2019–2022 on 30 pregnant patients admitted here with lower limb fractures.18 patients presented with femoral fractures and 12 patients with tibial fractures. Details of the type of fracture and site of fracture, along with the type of intervention, were recorded. Roadside accident was the most common cause of trauma, followed by fall and then assault. Results: The following observations were made from the data collected during this study in the treatment of 30 cases of lower limb trauma during pregnancy. The mean age of patients in the study was 27 years. The most common cause of trauma was traffic accidents, followed by fall and assault. In our study, 18 patients (60%) presented with femoral fractures, and 12 patients (40%) with tibial fractures. Operative intervention was done for all femoral fractures and 6 tibia fractures.6 tibial fractures were managed conservatively. Among 18 femoral fractures, 15 were operated with plating and 3 with interlocking femur nails. Among 6 operated tibia fractures, 2 were operated with plating and 4 with interlocking tibia nail. All cases were evaluated with risks and benefits of operative treatment, positioning of the patient, type of anesthesia used, use of c-arm, radiation dose, intraoperative fetal monitoring and the risk associated with anesthetic agents, antibiotics, analgesics, and anticoagulants. Conclusions: Orthopedic trauma during pregnancy is usually associated with significant morbidity and mortality to the mother as well as fetus. A multidisciplinary approach should be used for the successful management of lower limb fractures during pregnancy. The orthopedic surgeon must consider both operative and non-operative measures. Risk and benefits of operative treatment must be weighed carefully. Many fractures during pregnancy can be managed conservatively based on the fracture pattern and displacement. Also, we can delay the operative treatment until after delivery which is often a safe option. In fractures where surgical intervention is necessary, orthopedic surgeons must consider the physiologic changes that accompany pregnancy and the potential risks to the fetus. The surgeon must take care of the proper positioning of the patient, use of the c-arm, radiation dose, and intraoperative fetal monitoring. Furthermore, the risk associated with anesthetic agents, antibiotics, analgesics, and anticoagulants must be taken care of.

Dose Images Reconstruction Based on X-ray-Induced Acoustic Computed Tomography

The accurate reconstruction of the in vivo dose is a critical step in radiation therapy. X-ray-induced acoustic imaging is a promising technology for in vivo dose reconstruction, as it enables the nonradiative and noninvasive monitoring of radiation dose. However, current X-ray acoustic imaging methods suffer from several limitations, including high signal-to-noise ratio, poor imaging quality and massive loss of structural information. To address these limitations, we propose a dose image reconstruction method based on tensor sparse dictionary learning. Specifically, we combine tensor coding with compressed sensing data, extend two-dimensional dictionary learning to three-dimensional by using tensor product, and then utilize the spatial information of X-ray acoustic signal more efficiently. To reduce the artifacts of reconstruction images caused by spare sampling, we design the alternate iterative solution of the tensor sparse coefficient and tensor dictionary. In addition, we build the X-ray-induced acoustic dose images reconstruction system, simulate the X-ray acoustic signals based on patients’ information from Sichuan Cancer Hospital, and then create the simulated datasets. Compared to some typical state-of-the art imaging methods, the experimental results demonstrate that our method can significantly improve the quality of reconstructed images and the accuracy of dose distribution.

A radichromic dye of tris-(4-aminophenyl)methane incorporated into polymeric films for radiation dose monitoring

With the goal of developing new dyed film dosimeters for radiation technology applications, radiochromic films based on tris(4-aminophenyl)methane, a radiation-sensitive dye, have been studied for dose monitoring in the dose range of 0.5–25 kGy. A chlorine-containing material, hexachloroethane, was incorporated into these films to improve their radiation sensitivity. In addition, a UV-absorber of tinuvin-P were employed to protect these films from the influence of light during storage and measurements. Subjecting these films to γ-irradiation induces a significant magenta color characterized by an absorption band at 553 nm. The intensity of this band increases linearly as the absorbed dose increases up to 25 kGy and 10 kGy for compositions without and with HCE, respectively. The radiation sensitivity of the films incorporating 5.0 phr HCE is ∼2.4 times greater than that of films without HCE. The irradiated dyed films remain stable at 6 °C over two months in the dark. The responses of films are relatively independent of relative humidity in the 53–75% range and temperature in the 8–34 °C range. However, the films’ response is temperature dependent above 34 °C, thus it is advisable to calibrate these films under actual used conditions. The estimated absorbed doses using these films have an uncertainty (2σ) of 6.63%. In conclusion, the prepared dyed films may be good candidates for use as chemical dosimeters or indicators for applications involving radiation processing, such as food irradiation and medical sterilization.

Making CT Dose Monitoring Meaningful: Augmenting Dose with Imaging Quality.

Due to the concerns about radiation dose associated with medical imaging, radiation dose monitoring systems (RDMSs) are now utilized by many radiology providers to collect, process, analyze, and manage radiation dose-related information. Currently, most commercially available RDMSs focus only on radiation dose information and do not track any metrics related to image quality. However, to enable comprehensive patient-based imaging optimization, it is equally important to monitor image quality as well. This article describes how RDMS design can be extended beyond radiation dose to simultaneously monitor image quality. A newly designed interface was evaluated by different groups of radiology professionals (radiologists, technologists, and physicists) on a Likert scale. The results show that the new design is effective in assessing both image quality and safety in clinical practices, with an overall average score of 7.8 out of 10.0 and scores ranging from 5.5 to 10.0. Radiologists rated the interface highest at 8.4 out of 10.0, followed by technologists at 7.6 out of 10.0, and medical physicists at 7.5 out of 10.0. This work demonstrates how the assessment of the radiation dose can be performed in conjunction with the image quality using customizable user interfaces based on the clinical needs associated with different radiology professions.