Search Results (538)

Monitoring ultraviolet (UV) radiation dose distribution is crucial in many fields, like medicine and materials science, but traditional point-of-care methods limit the ability to fully assess the spatial extent of the irradiated surface. This paper presents the characterisation of a two-dimensional (2D) dosimetry system based on Pluronic F-127 hydrogel matrix doped with 2,3,5-triphenyltetrazolium chloride (TTC) with respect to exposition to UVA radiation. The hydrogel matrix (25% w/w) provides both high transparency and mechanical stability, while TTC (0.1% w/w) functions as a colour precursor that undergoes irreversible reduction to form water-insoluble red formazan upon UVA exposure. The insolubility of TTC formazan ensures that the resulting colour changes remain spatially stable within the dosimeter. The study included sample preparation in flat PMMA containers and analysis of the effect of radiation field uniformity in a UVP CL-1000 exposure chamber. It was supported by application of Kodak X-Omat 100 NIF UV Film dosimetry. The actual dose distribution in the chamber was shown to be significantly heterogeneous (CV coefficient of variation of approximately 18%), which emphasises the need for 2D dosimeters for precise validation of irradiation devices. The use of flatbed scanning and dedicated image analysis software allowed obtaining precise 2D dose distribution maps. The dosimeter was characterised in the dose range of 0–5000 mJ/cm², showing a reproducible response (R² = 0.9967). A resolution test was conducted to assess the precision of geometric representation. In the final stage of the study, the suitability of the developed dosimetry system was verified under conditions simulating heterogeneous UV radiation dose distribution using patterns printed with Computer-to-Film (CtF) technology. The results showed that optical effects in printed films significantly affect UV transmission, limiting accurate dose recording for black coverage above approximately 40–50%. The results obtained confirm that the TTC-Pluronic F-127 system is an effective, simple and low-cost tool for 2D monitoring of UVA radiation, with potential applications in cosmetology, dermatology, and material ageing tests. Full article

Background: Although diagnostic reference levels (DRLs) based on anatomical regions are widely used in computed tomography (CT) imaging, a clinical-indication-based approach provides a more accurate representation of daily practice and protocol variation. This study aimed to establish typical radiation doses for common CT clinical indications among adult patients at King Abdulaziz University Hospital (KAUH) in Saudi Arabia. Methods: This retrospective cross-sectional study included 298 adult patients who underwent CT examinations between 2020 and 2025 using two dual-source scanners operating in single- and dual-source modes. Demographic data, acquisition parameters, and radiation dose metrics, including CT dose index (CTDI_vol) and the dose–length product (DLP), were extracted from scanner consoles. Six clinical indications were analyzed: brain trauma, sinusitis, chest metastases (chest Mets), interstitial lung disease (ILD), abdominopelvic metastases (AbdPel Mets), and hernia. Results: Typical median CTDI_vol values in mGy were 36.4 for brain trauma, 3.4 for sinusitis, 4.9 for chest Mets, 5.6 for ILD, 7.2 for AbdPel Mets and hernia. Corresponding DLP values in mGy·cm were 654, 50, 173, 188, 344, and 369, respectively. Brain trauma demonstrated the highest radiation exposure, whereas sinusitis CT showed the lowest. Most values were comparable to or lower than international DRLs. Conclusions: This study provides the first comprehensive clinical-indication-based DRL data in Saudi Arabia beyond anatomical benchmarks, supporting ongoing dose optimization and future national DRL development. Full article

Background: Coronary bifurcation lesions represent one of the most technically demanding scenarios in coronary artery disease (CAD), associated with higher procedural complexity, restenosis, and periprocedural complications. Recent advances in coronary computed tomography angiography (CCTA) have markedly improved its ability to visualize complex coronary anatomy, assess plaque morphology, and guide revascularization. Objectives: This review summarizes (1) technological advances in CCTA over the last decade, (2) its role in evaluating bifurcation stenosis, (3) assessment of plaque morphology and distribution, (4) quantification of bifurcation geometry, and (5) emerging evidence supporting its application in revascularization planning and guidance. Findings: Modern wide-detector and dual-source CT systems, iterative and deep-learning reconstruction algorithms, and photon-counting CT (PCCT) have significantly improved temporal and spatial resolution, reduced blooming artifacts, and lowered radiation dose. CCTA now reliably quantifies bifurcation stenosis and plaque distribution, characterizes high-risk plaque features, and accurately measures bifurcation angles. The integration of CT-derived fractional flow reserve (FFR-CT) and artificial intelligence (AI)-based plaque quantification further strengthens its diagnostic and prognostic performance. CCTA-derived bifurcation scores and 3D modelling support procedural strategy selection, stent sizing, and side-branch (SB) protection. Conclusions: CCTA has evolved into a comprehensive tool for non-invasive diagnosis, physiological assessment, and pre-procedural planning of bifurcation disease. With the advent of PCCT and AI-enhanced quantitative tools, CCTA is poised to become a central component of revascularization decision-making in complex coronary bifurcations. Full article

Introduction: Systematic endoscopic mediastinal lymph node (LN) staging in early stage non-small-cell lung cancer (NSCLC) is widely recommended for optimal pre-operative staging due to imperfect accuracy of PET/CT. The SEISMIC study utilized synoptic reporting of findings during systematic endoscopic staging to inform radiotherapy planning in patients with locally advanced NSCLC and established a significant rate of discordance between PET-identified extent of disease and observed findings following EBUS. International guidelines recommend systematic LN staging in patients with clinical nodal stage (cN) 1–3 disease as a quality indicator, though performance metrics for quality assessment of systematic endoscopic mediastinal staging in NSCLC have not been described. Methods: A post hoc analysis of 155 participants with locally advanced NSCLC recruited to the SEISMIC study who underwent systematic endoscopic mediastinal staging, with sampling of all LN ≥ 6 mm, prior to planning of radical or high-dose palliative radiation, was completed. Synoptic procedural reports and pre-procedure PET imaging were examined to determine the number of LN sampled, as well as the number of radiologically normal LN (<10 mm diameter, no PET-avidity) sampled, and to establish the completeness of mediastinal staging. Results: Sampling was performed from a median two LN per patient. Sampling from at least one radiologically normal LN was performed in 92/155 (59%) participants, with ≥2 radiologically normal LN sampled in 47 participants (30%). PET-occult LN disease was identified in 18 of 92 (20%) of patients who underwent sampling of radiologically normal LN. The number of LN sampled in individual patients was largely influenced by the number of observed LN ≥ 6 mm in the short-axis dimension. Among these 76 participants staged cN2a by PET, EBUS identified PET-occult metastases in seven (9%), with four (5%) upstaged to cN2b and three (4%) to cN3. In only three patients (2% of cohort) were LN > 6 mm at higher station than the highest LN identified by PET not sampled endoscopically, confirming a high rate of complete mediastinal assessment. Conclusions: Quality of systematic staging in the SEISMIC study was high. Synoptic reporting supports high quality systematic endoscopic mediastinal LN staging in NSCLC and enables performance monitoring of systematic EBUS staging. Novel quality metrics are proposed for quality assessment, and consistent use of these may encourage more extensive LN sampling. Full article

Background: Sarcopenia, characterized by progressive loss of skeletal muscle mass and function, is becoming increasingly prevalent with the global population aging. Computed tomography (CT) is widely used for muscle assessment; however, concerns regarding radiation exposure have prompted interest in lower-dose imaging protocols. This study investigated the performance of radiomics-based machine learning (ML) models for sarcopenia detection using abdominal CT (APCT) and low-dose CT (LDCT). Methods: Radiomics features were extracted from CT images following skeletal muscle segmentation, and ML models were developed using logistic regression, support vector machine, and random forest. Model performance was evaluated using fivefold cross-validation with out-of-fold predictions. Results: The random forest model demonstrated the best performance among the evaluated models, achieving an area under the receiver operating characteristic curve of 0.720 (95% CI: 0.532–0.881) for APCT and 0.692 (95% CI: 0.573–0.801) for LDCT. Model interpretation using SHapley Additive exPlanations analysis identified several intensity-based radiomics features, including TotalEnergy, as important contributors to sarcopenia prediction. Conclusions: These findings suggest that radiomics features derived from LDCT images may provide useful information for sarcopenia detection. Because LDCT is widely used in clinical settings such as lung cancer screening, radiomics analysis of LDCT images may offer an additional opportunity for opportunistic sarcopenia assessment. Full article

The use of intraoperative computerised tomography (CT) to aid surgical management of facial fractures obviates the need for postoperative surgical scans, decreases return to theatre rates, and subsequently decreases overall hospital stay. This allows for better appreciation of a complex operative landscape in almost real time, and may become the gold standard of treatment. As with radiological investigations, decreasing radiation exposure of patients is a key goal. The aim of this study was to examine the effective radiation doses in patients undergoing surgical management of their facial fractures with the aid of a fixed-arm CT. This retrospective study was conducted on patients who underwent surgical fixation of their facial fractures within a hybrid surgical suite equipped with a fixed-arm cone beam CT (CBCT) from July 2023 to November 2024. The CBCT was used to assess adequacy of bony fixation. Data from imaging was collected to assess total effective radiation dose. Data from 30 random patients who underwent standard CT facial bones (CTFB) were collected as control. Data from 24 patients was collected. The majority were male (17/24, 70.8%) with an age range of 20–94 years. The average dose of the effective doses calculated in the CTFB cohort was 0.64 mSv (SD 0.05). This is a more-than-twenty-five-fold reduction in the average effective dose in the CBCT cohort, which was 0.025 mSv (SD 0.01). There was a statistically significant difference between the two cohorts with p < 0.0001 (95% CI 0.60–0.64). This study demonstrates that intraoperative CBCT delivers a significantly lower effective dose to patients compared with postoperative CTFB. Where facilities exist, CBCT offers a safer and more efficient alternative, with future work needed to assess staff dose, wait times, and cost impacts. Full article

Cone-beam computed tomography (CBCT) is widely used in image-guided radiotherapy because of its low radiation dose and on-board acquisition capability. However, CBCT images often suffer from scatter artifacts, increased noise, reduced soft-tissue contrast, and inaccurate Hounsfield Unit (HU) values, which limit their direct use for accurate dose calculation and quantitative analysis. To address this limitation, we propose a CBCT-to-CT synthesis framework based on 2.5D context encoding (concatenating five adjacent slices along the channel dimension) and latent-space variational diffusion. The proposed method combines a Vector Quantized Variational Autoencoder (VQ-VAE) and a U-shaped Vision Transformer (U-ViT)-based latent-space Variational Diffusion Model (VDM) to translate CBCT images into synthetic CT (sCT) images in a compressed latent space. To incorporate inter-slice anatomical context while preserving the computational efficiency of 2D processing, five adjacent CBCT slices are concatenated along the channel dimension and used as input. We evaluated the proposed method on the SynthRAD2025 paired CBCT-CT dataset covering head-and-neck, thoracic, and abdominal regions. Under the provided benchmark setting, quantitative evaluation on the validation set showed that the proposed 2.5D model improved peak signal-to-noise ratio (PSNR) from 25.39 dB to 27.44 dB (averaged across regions), structural similarity index measure (SSIM) from 0.813 to 0.846, reduced mean squared error (MSE) from 0.00313 to 0.00200, and lowered Fréchet inception distance (FID) from 1009.33 to 869.53 compared with the 2D baseline. Qualitative results also showed improved anatomical consistency and reduced artifact-related distortions. These findings suggest that neighboring-slice context can enhance HU fidelity and overall image quality in a computationally practical synthesis framework, supporting the usefulness of efficient AI-based cross-modality reconstruction for radiotherapy-related imaging workflows. Full article

Background and Objectives: Minimally invasive cervical spine surgery (MIS-CSS) relies heavily on intraoperative fluoroscopic imaging, raising concerns about radiation exposure to patients and surgical staff. Unlike lumbar MIS, cervical-specific radiation exposure has not been systematically reviewed, despite distinct anatomical considerations, including proximity to the thyroid gland and lens of the eye. This review aims to quantify intraoperative radiation exposure during MIS cervical spine procedures and evaluate available dose-reduction strategies. Materials and Methods: A systematic literature search was conducted across PubMed/MEDLINE, Scopus, and Google Scholar in April 2026 following PRISMA 2020 guidelines. Studies reporting original quantitative radiation data during minimally invasive cervical spine procedures in adult patients (≥10 patients) were included. Quality was assessed using the MINORS tool and the JBI checklist. Results: Seven studies encompassing 380 patients were included. Procedures comprised ACDF (four studies), minimally invasive posterior cervical laminoforaminotomy (two studies), and CT-navigated cervical instrumentation (one study). Patient effective doses during ACDF ranged from 0.015 to 1.3 mSv, with thyroid doses of 0.194–0.290 mGy. Standalone ACDF reduced patient dose by 36–58% compared to plated ACDF (p < 0.001). Navigation-assisted posterior cervical foraminotomy achieved a median fluoroscopy time of 10 s with negligible staff exposure. Surgeon per-procedure exposure during cervical discectomy (chest 0.122 µSv, lens 3.1 µSv, hands 7.1 µSv) was approximately half that of lumbar discectomy. Conclusions: Radiation doses during individual MIS cervical procedures appear to be within occupational safety limits, though the current evidence is insufficient to establish definitive dose thresholds. Standalone implant designs and intraoperative navigation represent effective, complementary dose-reduction strategies. Standardized prospective research is needed to establish cervical-specific radiation safety benchmarks. Full article

This study evaluated quantitative accuracy of the coronary artery calcium score (CACS) and the associated radiation dose reduction achieved by applying the fast non-local means (FNLM) algorithm to non-electrocardiography (ECG)-gated, low-dose chest computed tomography (CT) images acquired with a high-pitch scan and tin filter. Thirty patients underwent standard-dose CACS and low-dose chest CT were retrospectively analyzed. The processed low-dose images using the FNLM algorithm demonstrated a 4.2–5.0% mean CACS decrease and ≤16.4% median value increase relative to the standard-dose CACS CT but without statistical significance (p > 0.05). Notably, the quantitative error progressively decreased with increasing algorithm strength. The Pearson correlation coefficient reached 0.949 at Stage 3, indicating robust agreement with the standard-dose CACS CT. When stratified by patient heart rate, the high heart rate cohort exhibited the largest scoring errors but without statistical significance (p > 0.05). Importantly, the FNLM-processed protocol substantially reduced radiation dose, decreasing the mean volume CT dose index by 71.2% and dose-length product by 56.5% (p < 0.05). FNLM proves to be an effective post-processing technique that preserves CACS accuracy in non-ECG-gated, low-dose chest CT, thereby offering a clinically viable alternative imaging protocol for patients requiring routine screening. Full article

Introduction: Computed Tomography (CT) brain imaging provides high-resolution anatomical detail but involves relatively higher radiation doses, necessitating dose monitoring and optimisation. Diagnostic reference levels (DRLs) are recommended dose indicators for optimising radiation exposure without compromising diagnostic image quality; however, national DRLs for CT brain imaging have not yet been established in South Africa. This article presents a protocol for establishing local DRLs for non-contrast- (non-CE) and contrast-enhanced (CE) adult CT brain examinations at an academic hospital in Johannesburg, South Africa. Materials and Methods: The research site is at a single hospital in Johannesburg, South Africa. The research design for this study is retrospective. A sample of 197 adult CT brain examinations (63 non-CE, 34 CE, and 100 combined non-CE and CE examinations) performed between 1 January and 31 December 2024 will be used to develop local DRLs. The 64-slice CT scanner of choice for data collection is the Siemens SOMATOM Definition AS. The population defined for this study is individuals aged 18–70 years. The preferred contrast media used for CT brain examination at the research site is 40 mL of Omnipaque 350. The scan range for CT brain is from the base of the skull (foramen magnum) to the vertex, ensuring full coverage of intracranial structures. Dose metrics, including the volumetric CT dose index (CTDIvol) and dose–length product (DLP), will be extracted from archived dose reports. Local DRLs will be established as the 75th percentile values of CTDIvol and DLP for each protocol group. Descriptive statistics (mean, median, and interquartile range) will be used to summarise the data demographics. The effective dose will be estimated by applying a head-specific conversion coefficient to the DLP values. Results: As this is a study protocol, results are not yet available. Local DRLs will be reported as the mean, median, and 75th percentile values of the DLP and CTDIvol for non-CE, CE, and for both non-CE and CE CT brain examinations. The effective dose will be estimated by applying a head-specific dose conversion coefficient (k-factor) to the mean DLP values. Expected Outcomes: This study is expected to establish local DRLs for adult CT brain examinations, providing baseline data for dose optimisation and supporting the future development of national DRLs in South Africa. Conclusions: Establishing local DRLs will support the optimisation of the radiation dose in CT brain imaging to keep the dose as low as reasonably achievable. The DRLs developed for this study will contribute to national and international efforts toward optimising radiation dose during diagnostic X-ray imaging investigations. Full article

Background: The increasing use of computed tomography (CT) has led to a substantial rise in population exposure to ionizing radiation, highlighting the need for accurate and individualized dose assessment methods. This study aimed to evaluate a novel dosimetric parameter—the size-specific dose–length product (DLPss)—in low-dose chest CT (LDCT) protocols and to compare its performance with conventional dose metrics. Methods: A retrospective single-center analysis was conducted in a cohort of 221 patients undergoing LDCT of the chest. Anthropometric parameters were used to calculate the size-specific conversion factor (k), enabling determination of SSDE and DLPss. Dose parameters (CTDIvol, DLP, SSDE, and DLPss) were analyzed and compared with data from a standard chest CT cohort (n = 134) from the first study in the series. The contribution of the topogram to total radiation dose was also assessed. All examinations were considered diagnostically adequate in routine clinical evaluations. Results: The mean CTDIvol in the LDCT group was 1.33 mGy, with a DLPss of 61.93 mGy·cm and an estimated effective dose below 0.7 mSv, representing a dose reduction exceeding 82% compared to standard CT. DLPss values were approximately 23% higher than conventional DLP, indicating underestimation of dose by standard metrics. The topogram accounted for 10.23% of total radiation dose in LDCT, significantly higher than in standard CT (1.84%). Significant sex-related differences were observed in CTDIvol, DLP, and DLPss, but not in SSDE. Conclusions: DLPss provides a more comprehensive and individualized assessment of radiation exposure than conventional dose metrics by integrating patient size and scan length. The substantial contribution of the topogram to total dose in LDCT highlights the need for its optimization, particularly in long-term screening programs. From a clinical perspective, implementation of DLPss may improve patient-specific risk stratification and support more precise monitoring of cumulative radiation exposure, especially in populations undergoing repeated imaging, such as lung cancer screening cohorts. Advanced reconstruction algorithms, including deep learning-based methods, may enable further dose reductions and warrant future clinical investigation. Full article

Objectives: This study aimed to establish local Diagnostic Reference Levels (DRLs) for adult computed tomography (CT) across Emirates Health Services (EHS) hospitals in the United Arab Emirates. Methods: A retrospective multicenter survey included 1257 adult patients from seven EHS hospitals who underwent six routine CT protocols: head without contrast (n = 375), chest without contrast (n = 403), chest with contrast (n = 50), abdomen–pelvis without contrast (n = 204), abdomen–pelvis with contrast (n = 164), and chest–abdomen–pelvis (n = 61). Only single-phase, standard-range examinations were included. Examinations with major protocol deviations, extended scan ranges, or manual exposure overrides were excluded. CTDIvol and DLP were extracted from DICOM dose reports and reviewed against protocol definitions and scanner dose documentation. Local DRLs were defined as the 75th percentile of the dose distribution for each protocol, and median values were reported as achievable dose indicators. Results: Inter-hospital variability was observed across all protocols, particularly for abdomen–pelvis and chest–abdomen–pelvis examinations. The proposed DLP-based local DRLs (mGy·cm) were: head without contrast, 1179.6; chest without contrast, 425.0; chest with contrast, 1238.0; abdomen–pelvis without contrast, 637.2; abdomen–pelvis with contrast, 1269.9; and chest–abdomen–pelvis, 1411.5. Median values indicated achievable doses below the 75th percentile for all protocols. Compared with selected international studies, abdomen–pelvis doses were broadly comparable, whereas head and chest doses were somewhat higher. Conclusions: This study provides a coordinated multicenter baseline for adult CT local DRLs across EHS hospitals. The findings support protocol harmonization, scan-length optimization, targeted staff training, and integration with dose-monitoring systems to strengthen CT dose optimization and patient safety and to inform future updates of UAE national DRLs. Full article

We evaluated global radiotherapy practices in the management of early-stage (AJCC/UICC 8th edition stages I-II) glottic cancer (ESGC). A cross-sectional online survey was conducted in March 2025 across centers worldwide. Data was collected on clinical practices, including staging, CT simulation, target volumes delineation, organs-at-risk contouring, radiotherapy techniques, dose and fractionation schedules, treatment delivery techniques, and image guidance practices. A total of 181 responses were received, primarily from Asia (41.4%) and Europe (24.3%). Most respondents were from non-academic public centers (44.2%), with multidisciplinary team involvement reported by 84.5%. Head and neck CT scan was the most used staging modality (80.1%). Intensity-Modulated Radiation Therapy was the most common planning technique (82.9%). Hypofractionated radiotherapy schedules predominated for T1 (84%) and T2 (72.4%) disease. T1a was typically treated with whole-larynx target volume (72.4%). Use of ipsilateral involved vocal cord irradiation varied by geographical region (p = 0.015), being most common in North America (44.8%) and Europe (38.6%). Accelerated fractionation for T2 also differed significantly (p < 0.001), with the highest use reported in North America (41.4%). Daily Cone-Beam Computed Tomography was acquired by (58.2%). In total, 70% of respondents expressed interest in the results of a future phase III randomized trial comparing stereotactic body radiation therapy to conventional radiotherapy. Significant global variations in radiotherapy practices for ESGC were observed, likely reflecting disparities in access and differences in institutional protocols. The development and implementation of standardized, evidence-based global guidelines are essential to harmonize care, minimize toxicity, and improve outcomes for patients with ESGC. Full article

Background and aim: Chest CT is a major contributor to population radiation exposure. Conventional, pooled diagnostic reference levels (DRLs) do not account for inter-individual variability in body habitus and are typically used retrospectively. We evaluated dose behavior in adult chest CT, derived BMI-stratified local DRLs, and developed models to enable AI-assisted, prescan dose prediction. Methods: Consecutive adult chest CT examinations from a single center were analyzed. Dose indices (CTDIvol, DLP) and patient factors (BMI, weight, height, age, sex; scan length and planned technical parameters where available) were extracted. DRLs were defined as the 75th percentile overall and within BMI categories (underweight, normal, overweight, and obese). Group differences were assessed using non-parametric tests; associations were examined using correlation analysis. Supervised learning (e.g., Random Forest, Gradient Boosting) was trained to predict CTDIvol and DLP from routinely available variables. Results: BMI-stratified DRLs increased monotonically with habitus: underweight 444.95 mGy·cm/9.60 mGy; normal 513.00/11.55; overweight 756.08/14.65; obese 931.60/20.25 (DLP/CTDIvol). Differences across BMI groups were significant for DLP (H = 31.53, p < 0.001) and CTDIvol (H = 33.61, p < 0.001). DLP correlated moderately with weight and BMI (r ≈ 0.54–0.56, p < 0.001), with a weaker association for age; height was not a meaningful predictor. No sex-based differences in CTDIvol or DLP were observed. Predictive models estimated CTDIvol and DLP with high performance (R² up to ~0.79 and ~0.77, respectively), enabling comparison of predicted dose against BMI-matched DRLs before acquisition. Conclusions: Size-aware, BMI-stratified DRLs provide clinically interpretable investigation levels that avoid pitfalls of pooled benchmarks. Coupled with robust prediction of individualized dose from routine variables, this framework supports a shift from retrospective audit to prospective, point-of-care dose governance and protocol optimization in chest CT. Full article

Objectives: Management of unstable pelvic fractures during pregnancy presents a major therapeutic challenge, requiring careful multidisciplinary evaluation to balance maternal benefits and fetal radiation risks. Methods: We report the case of a 32-year-old patient who presented with a pelvic fracture due to a road traffic accident at three months of pregnancy. A left sacroiliac osteosynthesis was performed to treat a left sacroiliac diastasis with pelvic osteosynthesis using a trans-iliosacral approach under cone-beam CT (CBCT) guidance using a very-low-dose protocol. Radiation parameters and fetal dose estimates were calculated in advance in collaboration with a medical physicist. Tight beam collimation, a reduced field of view, and minimization of fluoroscopic checks were applied to keep fetal exposure as low as reasonably achievable. This article aims to demonstrate the feasibility of managing a complex pelvic fracture using interventional radiology and to review the literature on management options and gestational age-dependent fetal risks. Results: The estimated cumulative fetal dose from initial imaging, open surgery, and CBCT-guided osteosynthesis remained below 70 mGy using a pregnant phantom (Duke Organ Dose–Dosewatch–General Electric system), which is below thresholds associated with deterministic effects. The procedure achieved optimal screw positioning with less than 40 s of fluoroscopy. Maternal postoperative recovery was favorable, and follow-up revealed normal fetal development. Conclusions: This case demonstrates that CBCT-guided percutaneous iliosacral screw fixation can be safely performed during pregnancy with meticulous planning, dose-reduction strategies, and multidisciplinary collaboration, maintaining fetal radiation exposure below accepted safety thresholds. Full article