Dose Area Product Research Articles

RADIATION PATIENT AND WORKER DOSE APPLICATION (SI PADI)

Medical procedures for diagnostic and therapeutic purposes currently use many sources of ionizing radiation. Monitoring patient and radiation worker doses is needed to keep the radiation dose received to a minimum. The purpose of the patient and radiation worker dose application is to facilitate the task of Medical Physicists in conducting patient and radiation worker dose audits so that they become faster and more effective. The patient and radiation worker dose application is made based on dose audits conducted by Medical Physicists by monitoring patient doses on CT Scan examinations using CT dose index volume (CTDIvol) and dose length product (DLP) parameters on CT Scans and patient doses of the Siemens Somatom 128 slice Cathlab using Dose Area Product (DAP) data on the Philips Azurion 7 C-Arm. Radiation worker dose audits are conducted using evaluation data from TLD badges, TLD eyes, and pocket dosimeters of radiation workers working at Karawang Regional Hospital. Data processing uses a spreadsheet program. The menus on the dashboard are combined with formulas so that the data automatically appears in tables, graphs, or special formats as needed. The radiation patient and worker dose information system (Si Padi) was successfully developed at Karawang Regional Hospital to realize efforts to optimize radiation protection and safety for patients and radiation workers. Keywords: patient dose, radiation worker dose, dose audit, CT dose index (CTDI), dose length product (DLP), dose area product (DAP), Si Padi application.

Dual-Fluoroscopy vs. Single-Fluoroscopy in Balloon Kyphoplasty: A Study of Efficiency and Safety

Background: Vertebral compression fractures (VCFs) are the most prevalent type of osteoporotic fractures, often causing significant pain, morbidity, and mortality. Vertebral augmentation procedures like balloon kyphoplasty (BK) are effective in treating VCFs. These procedures are typically performed using a single fluoroscopy machine (SF) for anteroposterior (AP) and lateral views. We have implemented a dual-fluoroscopy (DF) technique to reduce procedure time and radiation exposure. The goal of this study was to determine whether dual-fluoroscopy could optimize surgical efficiency without compromising safety, offering a more effective alternative to traditional single-fluoroscopy methods. Methods: This retrospective study included 126 patients who underwent BK with either SF (n = 74, 58.7%) or DF (n = 52, 41.3%) between 2020 and 2024. We collected data on procedure duration per pedicle (PDPP), radiation exposure (reference air kerma and dose-area product [DAP]), and radiation duration. A sub-analysis of post-learning phase cases was performed. Results: A learning curve was identified for the first 24 cases and 15 cases using the SF technique and DF technique, respectively, which was followed by a stabilization in procedure duration per pedicle (Levene’s statistic = 10.623, p = 0.002 for SD difference, p < 0.001 for mean PDPP difference). After the completion of the learning phase for both techniques, the DF group demonstrated a significantly shorter PDPP (11.83 ± 4.3 vs. 14.03 ± 5.57 min, p = 0.049). No significant differences were found in radiation exposure, including radiation duration (p = 0.577), reference air kerma, or DAP. Conclusions: Dual-fluoroscopy significantly reduces procedure time after the learning curve is overcome, improving efficiency without increasing radiation exposure. This technique holds promise for optimizing kyphoplasty workflow and safety, supporting broader clinical adoption.

Artificial Neural Network-based Model for Predicting Cardiologists’ Over-apron Dose in CATHLABs

Abstract Aim: The radiation dose that cardiologists receive in the catheterization laboratory is influenced by various factors. Handling high-stress tasks in interventional cardiology departments may cause physicians to overlook the use of dosimeters. Therefore, it is essential to develop a model for predicting cardiologists’ radiation exposure. Materials and Methods: This study developed an artificial neural network (ANN) model to predict the over-apron radiation dose received by cardiologists during catheterization procedures, using dose area product (DAP) values. Leveraging a validated Monte Carlo simulation program, we generated data from simulations with varying spectra (70, 81, and 90 kVp) and tube orientations, resulting in 125 unique scenarios. We then used these data to train a multilayer perceptron neural network with four input features: DAP, energy spectrum, tube angulation, and the resulting cardiologist’s dose. Results: The model demonstrated high predictive accuracy with a correlation coefficient (R-value) of 0.95 and a root mean square error (RMSE) of 3.68 μSv, outperforming a traditional linear regression model, which had an R-value of 0.48 and an RMSE of 18.15 μSv. This significant improvement highlights the effectiveness of advanced techniques such as ANNs in accurately predicting occupational radiation doses. Conclusion: This study underscores the potential of ANN models for accurate radiation dose prediction, enhancing safety protocols, and providing a reliable tool for real-time exposure assessment in clinical settings. Future research should focus on broader validation and integration into real-time monitoring systems.

Improving culprit artery identification with intraprocedural cone-beam CT aortography and its clinical impact in bronchial artery embolization.

To evaluate the impact of intraprocedural cone-beam CT (CBCT) aortography on culprit artery identification and clinical outcomes in patients undergoing bronchial artery embolization (BAE). Two hundred eighty-two patients with 317 BAE procedures were retrospectively reviewed. Patients who underwent preprocedural chest CT angiography (CTA) without intraprocedural CBCT aortography were categorized as Group A (n = 177). Patients who underwent both preprocedural chest CTA and intraprocedural CBCT aortography were categorized as Group B (n = 105). Whether CBCT can provide improved culprit artery identification and whether this improvement has a clinical impact were evaluated by comparing the two Groups. In Group B, CBCT aortography detected more culprit non-bronchial systemic arteries originating from the subclavian arteries compared to chest CTA (16 vs 3, p = 0.026), and the average number of embolized vessels was significantly higher than in Group A (2.47 ± 1.61 vs 2.03 ± 1.17, p = 0.016), while the procedure time was shorter (37.4 ± 22.0 vs 43.6 ± 22.7 min, p = 0.024). The recurrent hemoptysis rate was lower in Group B (17.5% vs 8.7%, p = 0.041), and the proportion of patients requiring subsequent procedures was significantly lower (12.4% vs 4.8%, p = 0.035). The changes in estimated glomerular filtration rate before and 3 days after the procedure (0.1 ± 12.8 vs 0.3 ± 11.0 mL/min/1.73 m2, p = 0.909) and total dose area product (DAP, 6119.5 ± 5725.7 vs 6906.2 ± 5978.6 uGym2, p = 0.279) were not significantly different between the two groups. BAE with intraprocedural CBCT aortography enabled the embolization of more culprit arteries, leading to lower recurrent hemoptysis rates without increasing the risk of renal deterioration and radiation hazards when compared to procedures without it. Question Does intraprocedural CBCT aortography improve culprit artery detection and clinical outcomes in BAE for hemoptysis? Findings CBCT aortography significantly improved the detection of additional culprit arteries, especially from non-bronchial systemic arteries, increasing the number of vessels treated during BAE. Clinical relevance Using CBCT aortography during BAE results in better long-term outcomes by reducing recurrent hemoptysis and the need for additional procedures, without increasing the risk of renal impairment.

Median dose area product and fluoroscopy time have stabilized on a low level during the last years: data from the swedish national catheter ablation registry

Abstract Background Despite the utilization of 3D-mapping systems, the use of fluoroscopy is still necessary in most procedures of catheter ablations of arrhythmias, but associated with serious health risks to both patients and operators. However, given the rapid improvement of the 3D-mapping systems, the usage of fluoroscopy has likely decreased during the past 15 years. Purpose The purpose of this study was to explore trends over time in usage of fluoroscopy in catheter ablation for all arrhythmias. Methods The Swedish Catheter Ablation Registry covers virtually all (>97%) catheter ablations performed in Sweden since 2005. Patients >18 years of age undergoing catheter ablation from January 1st 2006 to December 31st 2020 were included. Periprocedural data; median dose area product and fluoroscopy time were analyzed and compared. Periprocedural data were compared between 2006, 2015 and 2020 to find possible trends. Results A total of 61242 procedures were performed during the study period. The breakdown between the different arrhythmias was: 3% ventricular tachycardia (VT), 3% premature ventricular complex (PVC), 5% atrial tachycardia (AT), 7% atrioventricular junction ablation (AVJ), 10% atrioventricular reentry tachycardia (AVRT), 14% cavotricuspid isthmus ablation (CTI), 20% atrioventricular nodal reentry tachycardia (AVNRT) and 39% atrial fibrillation (AF). In 2006, the median fluoroscopy duration for AF, VT and PVC were recorded at 41, 32 and 37 minutes, respectively. Subsequently in 2015 the corresponding times were recorded at 14, 8 and 13 minutes. In 2020 respective procedures had a median fluoroscopy time of 11, 10 and 18 minutes (p< 0.001 for trend for all ablations). In 2006 median dose area product for AF, VT and PVC were 3998 cGycm2, 4300 cGycm2, and 5138 cGycm2, respectively. By 2015 the median dose area product had decreased to 1005 cGycm2, 432 cGycm2 and 1123 cGycm2 respectively. In 2020 the median dose area product had decreased further to 524 cGycm2, 380 cGycm2 and 848 cGycm2 (p<0.001 for trends for all ablations). See figure 1 for all procedures. Conclusion Fluoroscopy time and median dose area product have decreased significantly over a 15-year period and have stabilized on a low level over the last 5 years. Given the associated risks, efforts to further reduce radiation exposure are clearly warranted.Median dose area product

Collision mapping enables accurate localization of the slow pathway in atrioventricular nodal reentrant tachycardia

Abstract Introduction Atrioventricular Node Reentry Tachycardia (AVNRT) is commonly treated with catheter ablation, with high success and low complication rates. However a small risk of complete AV block still remains. Recent studies could show that using collision map is a feasible approach in mapping the slow pathway. The aim of the current study is to show a reduction of the total ablation points needed to modify/ablate the slow pathway using the collision mapping compared to conventional 3D mapping guided slow pathway modulation/ablation and therefore minimize the risk of a complete heart block. Methods Patients diagnosed with AVNRT (n = 24) underwent collision mapping for slow pathway identification, compared to a historical cohort (n=76) using conventional mapping. For collision mapping a dynamic visualization of atrial propagation during sinus rhythm was condcted. Two propagation fronts were observed to collide at the triangle of Koch, one propagation through the slow and one through the fast pathway. The designated collision zone was considered ideal for catheter ablation (Figure 1). The endpoint after ablation in both groups was non-inducibility of AVNRTs. Results After propensity score matching the collision mapping group needed significantly fewer ablation impulses (2 (IQR 1 - 5) vs. 6 (IQR 2,5 - 11,5) p = 0.002) and shorter ablation time (p < 0.001) compared to the conventional group (Table 1). No significant differences were observed in procedure time (p = 0.209), fluoroscopy time (p = 0.296), or dose area product (p = 0.391). Conclusion Collision Mapping in AVNRT ablation showed a notable reduction in ablation points, suggesting enhanced procedural efficiency and safety.Figure 1Table1

Distal versus conventional transradial access for coronary angiography: a pooled analysis from the randomized RAPID trial

Abstract Background Transradial access (TRA) is the recommended approach for coronary procedures considering safety benefits over femoral access with radial artery occlusion (RAO) being the most frequent complication. Although usually not clinically significant, the presence of RAO affects potential future procedures and medical treatments. Distal TRA (dTRA) has been suggested to reduce the risk of postprocedural RAO compared to conventional TRA (cTRA) with, however, inconsistent results in clinical trials. Purpose This study aimed to compare the efficacy and safety of dTRA versus cTRA in patients undergoing diagnostic coronary angiography. Methods The RAPID trial is a single-center, open-label, 2x2 factorial, randomized study of patients undergoing coronary angiography through a 6-F radial access. The trial was stopped early by the data and safety monitoring board after the second pre-planned interim analysis and inclusion of 600 participants. Patients were randomized to dTRA or cTRA with further stratification according to periprocedural heparin use and preexisting oral anticoagulation. The primary endpoints were the incidence of RAO assessed by vascular ultrasound and puncture-site related bleedings. Results The final study population consisted of 298 patients randomized to dTRA and 302 patients to cTRA. Periprocedural heparin was administered in 382 patients (63.7%) and percutaneous coronary intervention was performed in 161 cases (26.8%) without differences between the study groups (p=0.700 and p=0.465; respectively). Distal TRA was associated with a significantly increased number of puncture attempts (2.4 ± 2.0 versus 1.5 ± 1.2; p<0.001) and failed punctures leading to access site crossover (11.7% versus 5.0%; p=0.003). Consequently, the total procedure time was longer in the dTRA group (30 min versus 25 min; p=0.004) without increasing fluoroscopy time (p=0.320), dose area product (p=0.245), or contrast volume (p=0.884). Patent hemostasis was achieved in 91.7% of patients with cTRA. The rates of RAO (16.1% versus 15.6%, p=0.855) and puncture-site related bleedings (6.7% versus 8.3%; p=0.466) were similar in both groups. Conclusions According to this study, dTRA does not reduce the risk of RAO or bleeding events compared to cTRA.

Single versus double transseptal puncture for pulmonary vein isolation with radiofrequency catheter ablation for atrial fibrillation - insights from "Go for Zero Fluoroscopy" registry

Abstract Background Transseptal puncture is one of the most challenging steps in catheter ablation of atrial fibrillation (AF) because of the potential risk of complication. While single TSP reduces the puncture-related risk, double TSP simplifies the procedure (immediate signal visualization in pulmonary veins, avoidance of multiple changes of catheters through the single sheath). The purpose of this study was to analyze the impact of single versus double TSP during pulmonary vein isolation (PVI) with radiofrequency (RF) catheter ablation for AF on the fluoroscopy usage and procedure time. Methods Data reported from the international, multicenter prospective „Go For Zero Fluoroscopy Registry" performed in years 2018–2019 were analyzed. Overall 25 European electrophysiology centers from 14 countries and up to 5 operators from each center were enrolled. Only isolated PVI procedures were analyzed. Results A total data of 393 PVI RF procedures were collected from 25 centers. The median dose-area-product (DAP), fluoroscopy time and overall procedure time were: 810 (325 – 1839) cGy*cm2, 8 (4 – 14) minutes and 124 (92 – 168) minutes, respectively. Single TSP was associated with significantly higher DAP: 984 (459 – 1939) vs 667 (227 – 1469) cGy*cm2 (p=0.002), longer fluoroscopy time: 11 (6 – 19) vs 6 (3 – 11) minutes (p<0.001) and longer overall procedure time: 133 (103 – 168) vs 110 (90 – 168) minutes (p=0.003) as compared with double TSP. Single and double TSP group did not differ significantly in regards of general anesthesia usage, circular and multipolar mapping catheter use (p>0.05). However, single TSP was performed by operators with longer EP lab experience: 10 (4 – 15) vs 3 (0 – 10) years (p<0,001). Conclusions Double TSP is related with lower fluoroscopy usage and shorter overall procedure time of pulmonary vein isolation with radiofrequency catheter ablation for atrial fibrillation.

Twelve-month outcome of robotic assisted PCI

Abstract Background Robotics in interventional cardiology (R-PCI) is a technique with high potential for optimising the outcome of patients with coronary heart disease. In order to compare R-PCI with conventional, manual PCI (M-PCI), it is necessary to analyse both the index procedure during the initial hospital stay and, in particular, the long-term outcome. Methods We report twelve-month follow up data of our prospective FRiK registry, started in mid 2021. This registry focuses on success rates and safety, radiation dose of patients and personnel as well as long-term outcome (after 6 and 12 months). Moreover, R-PCI is compared with M-PCI in these categories. Results 73 patients received R-PCI. PCI success rate was 100%, with 17.8% requiring manual assistance. Rate of complications (MACE - major adverse cardiovascular events) was 0%. Compared with 152 M-PCI patients, treated by the same interventionalists, there was a higher median procedural time (diagnostic and intervention) 102.5 (82.8-123.5) min vs. 73 (51-101.5) (p<0.001) and fluoroscopy time 18.3 (14.4-26.6) min vs. 16.2 (9.8-23.4) min (p=0.037) in R-PCI patients. However, there was no significant difference between the dose-area product 4062 (2337-5990) cGycm² vs. 3747 (2238-5904) cGycm² (p=0.878) and contrast volume use 180 (140-250) ml vs. 180 (135-235) ml (p=0.370, figure 1). Twelve months after the intervention, all patients in both groups were alive. R-PCI and M-PCI had comparable rates of rehospitalisation (11.4% vs. 8.1%, p=0.903) and unscheduled PCI (4.3% vs. 2.7%, p=0.932, figure 2). Target vessel failure occurred in one vs. two patients in the R-PCI and M-PCI group, respectively (1.4% vs. 1.3%, p=0.932). Conclusion R-PCI showed a high success rate, low rates for need of manual assistance, and a very high safety profile without any complications. Also at 12-month follow-up, R-PCI was comparable to the M-PCI in all categories.Comparison of procedural characteristicsComparison of twelve-month outcome

Outcomes of Radiation Dose Reduction Protocol in Electrophysiologic and Cardiac Device Procedures

Background: Exposure to radiation has been demonstrated to be associated with adverse short- and long-term health outcomes. Objective: To presented outcomes before and after the implementation of a radiation dose reduction protocol in electrophysiologic (EP) and cardiac device procedures. Materials and Methods: The present study was a retrospective comparative study, conducted at Chiang Mai University Hospital in Thailand using 2017 and 2019 data, including all patients who underwent EP and cardiac implantable electronic device (CIED) procedures. Exclusion criteria involved patients with incomplete radiation dose records. The authors compared fluoroscopic time, radiation exposure, and complication rates before and after the protocol. Results: Among the 458 cases, with 214 Eps and 244 devices, the mean age was 58 years. For device implantation procedures, there was no significant change in fluoroscopic time as median (P₂₅, P₇₅) before and after protocol implementation were 3.1 (0.4, 5.8) versus 4.4 (1.2,7.6) minutes, respectively (p=0.117). However, there was a decreasing trend in dose area product (DAP) at 242.0 (119.2, 766.0) versus 197.9 (71.5, 494.5) cGy.cm² (p=0.073). The reduction in DAP was more pronounced in cardiac resynchronization therapy (CRT) implantation when comparing 2017 to 2019 were 1,933.6 (1,039.4, 7,683.8) versus 1,074.6 (427.2, 2,890.7) cGy.cm² (p=0.020). In EP procedures, fluoroscopic time significantly decreased from 8.1 (3.0, 14.3) minutes in 2017 to 1.0 (0.0, 3.6) minute in 2019 (p<0.001), accompanied by a significant reduction in exposure dose of 45.0 (10.8, 153.3) versus 1.7 (0.0, 31.6) mGy (p<0.001) and DAP of 1,022.9 (247.2, 2,660.3) versus 38.5 (0.0, 566.9) cGy.cm² (p<0.001). There was no difference in the complication rate between the two periods. Conclusion: The implementation of the radiation dose reduction protocol resulted in a significant decrease in radiation exposure during EP procedures and showed a trend towards reduction in CIED procedures.

Iodine Assessment of Carbon Dioxide Angiography in Iliac Branched Repair.

The objective of this study was to investigate whether the use of carbon dioxide (CO2) angiography decreases the intraoperative use of iodine contrast medium (ICM), thereby decreasing the risk of developing postoperative renal damage in patients undergoing iliac branch device (IBD) implantation. Patients undergoing IBD implantation at a single tertiary center between May 2013 and August 2019 were screened for inclusion in the study. A cohort of patients in whom an intraoperative imaging protocol using predominantly CO2 was compared with a control group in whom ICM was used (CO2 and ICM groups). Fusion imaging was used in both groups. Retrospective review of the medical charts and all imaging was performed. Variables were expressed as median with interquartile range (IQR) or absolute number and percentage. Wilcoxon-Mann-Whitney and χ2 tests were used to compare continuous and categorical variables, respectively. P values of <0 .05 were considered statistically significant. Twenty-three patients were included in the CO2 group and 21 in the ICM group without significant differences in patient characteristics between the groups. Intraoperative iodine exposure was lower in the CO2 group than in the ICM group (8.2 g [IQR, 7.1-10.9 g) vs 15.8 g (IQR 7.6-21 g); P = 0.015, respectively). There were no differences in technical success, clinical success, fluoroscopy time, and dose-area product in the 2 groups. There were no adverse events that could be related to the intraoperative use of CO2. There was no difference in postoperative survival nor renal function assessment between the groups despite the higher number of accessory renal arteries embolized in the CO2 group (P = 0.221). Reduction of intraoperative ICM exposure during IBD implantation is feasible through the predominant use of CO2 automated angiography. This can be done safely without affecting the technical success or radiation exposure. The immediate postoperative renal damage was low when a modern intraoperative imaging protocol with ICM was used and was not significantly reduced by the use of CO2. Further and larger studies are needed to investigate the long-term effects. This study aimed to investigate how to minimize intraoperative risk during iliac branched repair exploring the intraoperative use of automated carbon dioxide angiography in order to decrease the use of contrast media protecting renal function and thereby potentially impacting long-term survival.

Comparing Low-to-Zero Fluoroscopic Navigation Systems for AVNRT Catheter Ablation: A Network Meta-Analysis.

Low-to-zero fluoroscopic navigation systems lower radiation exposure which improves health outcomes. Conventional x-ray fluoroscopy (CF) has long been the standard to guide to catheter location for cardiac ablation. With advancements in technology, alternative safety navigation systems have been developed. Three primary modalities commonly utilized are three-dimensional electroanatomic mapping (3D-EAM), magnetic navigation system (MNS), and intracardiac echocardiography (ICE), all of which can reduce radiation exposure during the procedure. We aim to compare the efficacy and safety among ICE, EAM, MNS, and CF in ablation of atrioventricular nodal reentrant tachycardia (AVNRT). This is a meta-analysis consisting of observational studies and randomized controlled trials, which evaluated the performance of navigation systems of catheter ablation in AVNRT patients. Primary endpoint was to access the AVNRT recurrence after the procedure during follow-up periods. Secondary endpoints were technical success, fluoroscopic time, fluoroscopic dose area product, radiofrequency ablation time, and adverse events. Random-effect model was applied for pooled estimated effects of included studies. A total of 21 studies (21 CF, 2 ICE, 9 EAM, 11 MNS) including 1716 patients who underwent catheter ablation for AVNRT treatment were analyzed. Of these, 16 were observational studies and 5 were randomized controlled trials. Point estimation of AVNRT recurrence showed ICE exhibited a pooled odds ratio (ORs) of 1.06 (95% confidence interval [CI]: 0.064-17.322), MNS with ORs of 0.51 (95% CI: 0.214-1.219], and EAM with ORs of 0.394 (95% CI: 0.119-1.305) when compared to CF. EAM had significant higher technical success with ORs of 2.781 (95% CI: 1.317-5.872) when compared to CF. Regarding fluoroscopy time, EAM showed the lowest time with mean differences (MD) of -10.348 min (95% CI: -13.385 to -7.3101) and P-score of 0.998. It was followed by MNS with MD of -3.712 min (95% CI: -7.128 to -0.295) and P-score of 0.586, ICE with MD of -1.150 min (95% CI: -6.963 to 4.662) with a P-score of 0.294 compared to CF, which has a P-score of 0.122. There were insignificant adverse events across the procedures. AVNRT ablation navigated by low-to-zero fluoroscopic navigation systems achieves higher efficacy and comparable safety to conventional fluoroscopywhile also reducing risk of radiation exposure time.

Single-Stage Image-Guided Percutaneous Ablation with Thoracoscopic Resection for Multiple Pulmonary Lesions in a Hybrid Operating Room: A Retrospective Study.

Different approaches are required in treating patients with multiple pulmonary lesions. A multistage procedure may increase the risk of complications and patient discomfort. This study reports an initial experience with single-stage management of multiple lung lesions using percutaneous ablation with thoracoscopic resection in a hybrid operating room (HOR). We retrospectively evaluated patients who underwent combined ablation and resection in an HOR between May 2022 and July 2024. All patients received a single anesthesia via endotracheal tube intubation. The clinical data, operative findings, and pathological characteristics of the lung nodules were recorded. A total of 22 patients were enrolled in this study. Twenty patients underwent unilateral procedures, while the other two patients underwent bilateral procedures. Ablations were performed before lung resection in 21 patients; only 1 patient underwent surgery first. The median global operating room time was 227.0 min. The median total radiation dose (dose area product) was 14,076 μGym2. The median hospital postoperative length of stay was 2 days. The single-stage procedure of percutaneous ablation with thoracoscopic resection under general anesthesia in an HOR is feasible and safe. This procedure is an alternative method for managing multiple pulmonary lesions.

Coil Embolization for Cerebral Aneurysm Using Low Pulse Rate Fluoroscopy.

Although coil embolization is commonly perceived as a minimally invasive procedure, the associated radiation exposure cannot be disregarded. To date, no specific study has investigated radiation exposure during coil embolization. This study aimed to investigate the potential of lowering the pulse rate to decrease radiation exposure during coil embolization while maintaining patient safety. Radiation data and clinical features of 70 patients who underwent coil embolization between 2015 and 2020 were retrospectively analyzed. Since July 2017, the pulse rate was regulated from 7.5 to 4 frames per second (f/s). Statistical analyses were performed to examine the correlation between pulse rate and radiation exposure. Out of the 70 procedures, 30 were performed at the standard pulse rate (7.5 f/s), and 40 were performed at the lower pulse rate (4 f/s). In the lower-pulse-rate group, the absorbed dose to the patient (AK) was 2580.7 (±217) mGy, whereas in the standard-pulse-rate group, it was 4760 (±411.1). Both the dose-area product (DAP) and AK were substantially reduced in the low pulse rate group (p = 0.000002). There was a significant correlation between DAP and AK and pulse rate (p = 0.004, p = 0.0017, respectively). Moreover, there was no significant correlation between pulse rate and perioperative complications. Our findings suggest that using a lower pulse rate (4 f/s) can effectively reduce radiation exposure during coil embolization for cerebral aneurysms while ensuring patient safety.

An SSDLs calibration method for the kerma-area product meter

The kerma-area product meter (KAP meter) is mainly used for quality assurance in medical imaging research, providing dose quality assessment or dose monitoring for patients. It can be calibrated either in the laboratory or on-site. The purpose of this study is to propose a method for calibrating the KAP meter using a plane-parallel transmission ionization chamber in the SSDLs. In the range of 50 kV–150 kV, under RQR (standard radiation qualities) and RQR additional filtering conditions of the KAP meter, the correction factor NQm of the transmission ionization chamber is calculated to select two types of KAP meters for the calibration of the transmitted beam. The collimators used to limit the size of the radiation field are respectively 50.07 mm in length, 30.03 mm in length, and 20.05 mm in radius. This method, with uncertainty not exceeding 3.0% while improving calibration efficiency, can replace the unit-specific correction of the laboratory method (Toroi et al., 2008).

Comparative Analysis of Transradial and Transfemoral Approaches in Transarterial Radioembolization for Liver Tumors: A Systematic Review and Meta-Analysis.

Transarterial radioembolization (TARE) is a minimally invasive therapy combining embolization and radiation for cancer treatment. This meta-analysis compares radiation exposure, quality of life, and safety of the transradial (TRA) versus transfemoral (TFA) approaches in TARE for liver tumors. We searched PubMed, SCOPUS, Cochrane, EMBASE, and Web of Science for studies comparing TRA versus TFA in TARE for liver tumors. Our primary outcomes focused on various measures of patient radiation exposure, including procedure time, fluoroscopy time, air kerma, and dose-area product (DAP). For secondary outcomes, we evaluated safety parameters, such as overall pain experienced during the procedure, pain in the recovery room post-procedure, the incidence of adverse events, and the impact on quality of life. Study quality was assessed using Cochrane's ROB 2 tool for RCTs and the Newcastle-Ottawa scale for observational studies. Data analysis was conducted with REVMAN 5.4.1 software. Six studies, comprising one RCT and five cohort studies with 1,209 patients, underwent comprehensive analysis. The aggregated findings revealed a significant reduction in procedure duration associated with TRA (MD =- 6.30, 95% CI [- 9.88, - 2.73], P = 0.005). However, no statistically significant differences were found between TRA and TFA groups concerning fluoroscopy time, recovery time, air kerma, DAP, pain in the recovery room, overall pain during the procedure, quality of life measuring mental health and physical function or adverse events. TRA and TFA showed comparable results in TARE for liver tumors, but TRA offered a shorter procedure time. Further RCTs with larger samples are needed to confirm these findings. Future studies should assess long-term efficacy for a more complete evaluation.

Diagnostic reference levels for the city of Moscow during X-ray examinations

Diagnostic reference levels are one of the effective tools for optimizing patient radiation doses in diagnostic radiology. The staff of domestic radiology departments does not have an understanding of the development process and use of diagnostic reference levels during X-ray examinations, although this tool is a generally accepted in practice abroad. The article shows the experience of forming regional diagnostic reference levels based on measurements provided by the accredited testing laboratory of the Scientific and Practical Clinical Center for Diagnostics and Telemedicine Technologies of the Moscow Healthcare Department. The diagnostic reference levels for radiography in Moscow were developed for eight of the most common types of examinations based on the operation of 216 digital X-ray machines. The resulting levels, expressed in the dose-area product (cGy-cm2) and effective dose (mSv), were compared with the local diagnostic reference levels for the Ryazan region, Russia, and national diagnostic reference levels for other countries. The analysis showed continuity in the values. Some types of studies have been optimized. The developed diagnostic reference levels are the quality performance indicators foe diagnostic radiology departments and will be used to optimize a patient radiation dose during diagnostic studies in Moscow.

Establishment of typical values in cerebral thrombectomy according to the stroke anatomical region and procedure clinical outcome.

The aim of the study is to establish local diagnostic reference levels (DRLs) in cerebral thrombectomy, according to the anatomical region of ischemic stroke. This is a retrospective study from a single center involving 255 examinations. The proposed median values (P50) for thrombectomy are: 123Gy.cm2 for air kerma-area product (PKA) and 915mGy for air kerma (Ka,r). For middle cerebral artery (MCA) thrombectomies, the proposed DRLs are 118Gy.cm2 for PKA and 112Gy.cm2 for internal carotid artery (ICA). The Ka,r values for MCA and ICA are 849 and 775mGy, respectively. It was observed that 94.9% of patients presented grade 0 on the initial modified treatment in cerebral infarction (mTICI) scale, and after thrombectomy, 63.1% of patients reached a final mTICI grade of 3. Stents were implanted in 37 patients (14.5% of cases). It was concluded that 16.1% of patients exceeded one trigger value of the Safety in Radiological Procedures' recommended parameters. Establishing DRLs is an important tool for optimizing practices and is considered a standard for quality control.

Radiation Exposure with Self-Expandable Metallic Stent versus Transanal Decompression Tube for Malignant Colorectal Obstruction: A Post Hoc Propensity Score Matched Analysis.

Background: Although several reports have compared the outcomes of self-expandable metallic stent (SEMSs) and transanal decompression tube (TDT) placement for malignant colorectal obstruction (MCO), few studies have compared the radiation exposure (RE) associated with these two procedures. Consequently, we aimed to compare the RE of SEMS and TDT placements for MCO using propensity score matching (PSM) in a multi-center, prospective observational study. Methods: This study investigated the clinical data of 236 patients who underwent SEMS or TDT placement. The air kerma at the patient entrance reference point (Ka,r: mGy) and air kerma-area product (PKA; Gycm2) were measured and compared between SEMS and TDT groups after PSM. Results: After PSM, 61 patients were identified in each group. The median Ka,r in the SEMS group was significantly greater than that in the TDT group (77.4 vs. 55.6 mGy; p = 0.025) across the entire cohort. With respect to subgroup analyses by location, in the rectum, the median Ka, r and PKA were significantly greater in the SEMS group than in the TDT group (172.9 vs. 34.6 mGy; p = 0.001; and 46.0 vs. 18.1 Gycm2; p = 0.006, respectively). However, in the colon, the RE parameters did not significantly differ between the two groups. Conclusions: TDT might be a more suitable option for decompression in patients with malignant rectal obstruction due to its lower RE and technical advantages. Conversely, SEMS placement is recommended as the first decompression method to treat malignant colonic obstruction, in line with the current guidelines.

Intentionally unilateral prostatic artery embolization: Patient selection, technique and potential benefits.

Prostatic artery embolization (PAE) is a promising but also technically demanding interventional radiologic treatment for symptomatic benign prostatic hyperplasia. Many technical challenges in PAE are associated with the complex anatomy of prostatic arteries (PAs) and with the systematic attempts to catheterize the PAs of both pelvic sides. Long procedure times and high radiation doses are often the result of these attempts and are considered significant disadvantages of PAE. The authors hypothesized that, in selected patients, these disadvantages could be mitigated by intentionally embolizing PAs of only one pelvic side. To describe the authors' approach for intentionally unilateral PAE (IU-PAE) and its potential benefits. This was a single-center retrospective study of patients treated with IU-PAE during a period of 2 years. IU-PAE was applied in patients with opacification of more than half of the contralateral prostatic lobe after angiography of the ipsilateral PA (subgroup A), or with markedly asymmetric prostatic enlargement, with the dominant prostatic lobe occupying at least two thirds of the entire gland (subgroup B). All patients treated with IU-PAE also fulfilled at least one of the following criteria: Severe tortuosity or severe atheromatosis of the pelvic arteries, non-visualization, or visualization of a tiny (< 1 mm) contralateral PA on preprocedural computed tomographic angiography. Intraprocedural contrast-enhanced ultrasonography (iCEUS) was applied to monitor prostatic infarction. IU-PAE patients were compared to a control group treated with bilateral PAE. IU-PAE was performed in a total 13 patients (subgroup A, n = 7; subgroup B, n = 6). Dose-area product, fluoroscopy time and operation time in the IU-PAE group (9767.8 μGy∙m2, 30.3 minutes, 64.0 minutes, respectively) were significantly shorter (45.4%, 35.9%, 45.8% respectively, P < 0.01) compared to the control group. Clinical and imaging outcomes did not differ significantly between the IU-PAE group and the control group. In the 2 clinical failures of IU-PAE (both in subgroup A), the extent of prostatic infarction (demonstrated by iCEUS) was significantly smaller compared to the rest of the IU-PAE group. In selected patients, IU-PAE is associated with comparable outcomes, but with lower radiation exposure and a shorter procedure compared to bilateral PAE. iCEUS could facilitate patient selection for IU-PAE.