British Journal of Radiology最新文献

Coronary computed tomography angiography (CCTA) has evolved into a key non-invasive tool for evaluating coronary artery disease, offering high sensitivity, detailed anatomical visualization, and strong prognostic value. Current Society of Cardiovascular Computed Tomography guidelines recommend CCTA as a first-line test for symptomatic patients, while limiting its use in asymptomatic individuals to select high-risk cases. Advantages in a screening context include early detection of subclinical atherosclerosis, prognostic assessment through high-risk plaque features, and facilitation of personalized preventive strategies. However, widespread screening faces challenges: procedural complexity, contrast and radiation exposure, psychological impact, and economic cost. Emerging integration of artificial intelligence promises to enhance efficiency, automate plaque quantification, and enable individualized risk prediction, potentially improving cost-effectiveness and clinical adoption. Future validation through randomized controlled trials and real-world data is needed to confirm the impact of CCTA-based screening on cardiovascular event reduction, healthcare resource use, and patient quality of life.

Objectives: We sought to identify factors associated with prognosis and bleeding in patients with melanoma brain metastases(BM).Objectives were median overall survival (mOS [months]) and bleeding incidence.

Methods: We conducted a retrospective analysis of patients receiving SRS at our center 11/1511/23.Analysis was performed on Prism 10.1.1.Extraction from electronic medical records was undertaken by authors, with local R&D approval(NEU012).

Results: 81 patients were evaluable. 119 treatment courses were delivered. There were no bleeding events (BE) in the first 7 days , 1 within 28 days(0.8%) and 19 within 90 days(16%).7.6%(N = 9) died within 90 days and 25.2%(N = 30) died within 6 m. There were no deaths within 30 days or related to treatment.mOS was 17.6 m(95% CI 9.20-35.05).Significantly inferior survival outcomes were observed for patients with elevated lactate dehydrogenase(LDH),poor performance status(Karnofsky performance status [KPS]),higher total treated intracranial volume(GTV) and total number of BM.mOS of patients with a normal LDH was 37.0 m vs 5.2 m for those with LDH >ULN(HR 4.40, P<.0001).This was also true on multivariable analysis including KPS, BM number and BM size(HR 3.75 95%CI 1.94-7.30, p = <0.0001).For patients with KPS ≥90 mOS was 35.0 m vs 7.7 m for KPS ≤80(HR 2.55, P<.0004).This was significant using the multivariable analysis described above(HR 2.12 95%CI 1.123-3.948, p = 0.0181).

Conclusions: Despite theoretically high risk of bleeding after SRS in MM BM, incidence of bleeding in our cohort was low.mOS was comparable to historical controls of 16-23 months.

Advances in knowledge: We novelly performed univariate and multivariate analysis demonstrating poor survival outcomes in patients with high LDH, poor performance status and larger brain metastases (both by BM size and number).

Objectives: To determine the feasibility and accuracy of photon-counting detector (PCD)-CT for iron and fat quantification in the myocardium.

Materials and methods: Cylindrical tubes were filled with porcine myocardium and iron-citrate with iron concentrations of 0-20mg Fe/g. Dilution series were prepared with myocardium and iron (no-fat probes) and with 5%-fat (fat probes). The tubes were positioned in a chest phantom and were scanned with a calcium-scoring protocol on a PCD-CT. A re-parameterized three-material decomposition was used to separate iron and fat from myocardium.

Results: On virtual monoenergetic images, attenuation increased linearly with iron concentrations in both fat and no-fat probes. In no-fat probes, linear regression yielded a slope of 1.2HU/(mgFe/g) with an intercept of 35.8HU (R2=0.964). In the fat probes, the slope was similar at 1.1HU/(mgFe/g), while the regression line shifted downwards by 6.1HU with an intercept of 29.6HU (R2=0.985). Iron maps separated fat from iron with calculated median fat-fractions of 4.85 in the fat and 0.90 in the no-fat probes. In iron images, attenuation increased linearly with increasing iron concentrations, with similar slopes between fat and no-fat probes and negligible differences in the intercept.

Conclusion: Experimental evidence indicates the feasibility and accuracy of PCD-CT for iron and fat quantification in the myocardium. Iron-specific three-material decomposition eliminates the confounding effect of fat on myocardial iron quantification.

Advances in knowledge: This study highlights the value of dual-energy CT with three-material decomposition for quantifying iron and fat in the myocardium. Thus, CT could serve as alternative for the current reference standard MRI.

Objectives: To establish typical values (TVs) for air kerma at the reference point (Ka, r, mGy) and fluoroscopy time (minutes) in four interventional procedures: vascular angiography (pelvic/lower limbs), vascular angioplasty (pelvic/lower limbs), coronary angiography and angioplasty. The study also aimed to assess the influence of body mass index (BMI) and identify other clinical factors associated with radiation exposure.

Methods: A retrospective analysis of 2,200 patient examinations was performed at a large hospital. Demographic, anthropometric, dosimetric data were extracted from fluoroscopy equipment reports and electronic medical records. TVs were calculated overall and stratified by procedure type and BMI category.

Results: Variation in TVs was observed across procedure types and BMI groups. Ka, r values ranged from 185.0 mGy (underweight) to 796.5 mGy (class III obesity), with an overall TV of 413 mGy. Fluoroscopy time demonstrated a correlation with radiation dose. Age and sex influenced exposure but to a lesser degree. Relying on aggregated TVs may mask clinical differences, leading to under- or overestimation of patient dose.

Conclusions: Tailoring TVs to patient BMI and procedure type enhances dose assessment accuracy, supporting optimized radiation protection strategies in clinical practice.

Advances in knowledge: This study demonstrates that anthropometric characteristics have measurable impact on radiation dose indicators in interventional radiology and provides BMI-stratified TVs based on a clinical dataset. Although multiple factors influence radiation exposure, including procedural complexity and operator experience, anthropometry remains an independent contributor. The TVs presented here support protocol optimization and contextualization of local practice.

Cardiovascular magnetic resonance (CMR) can comprehensively assess cardiac function and structure, with a unique capability for tissue characterisation. However, its access remains limited due to general availability. Additionally, CMR has lengthy preparation and acquisition times. Various optimisation methods and techniques have been proposed to streamline CMR workflow and shorten total acquisition times. These include patient preparation, rapid imaging protocols, sequences developments, deep learning-based image acceleration and reconstruction, as well as automated image analysis and report generation. Together, these advances may grant CMR access to more patients and even enable more accessible non-invasive cardiac screening of high-risk and general population in the future. This narrative review provides an overview of different concepts and technologies aiming at optimising CMR in terms of workflow and image acquisition and highlights the opportunities for high-volume CMR studies to support more patient-centred cardiovascular care.

Background: To evaluate the diagnostic performance of tin-filtered 150 kV ultra-low dose CT (ULDCT) for pulmonary nodule detection and size measurement compared with standard-dose CT (SDCT).

Methods: This prospective study enrolled 261 patients who underwent both SDCT (120 kV) and ULDCT (150 kV with 0.6 mm tin filtration) during a single visit. Radiation dose parameters, subjective and objective image quality, and diagnostic performance were assessed using SDCT as the reference standard. Nodules were classified as solid, pure ground-glass (pGGNs), or mixed ground-glass nodules (mGGNs), and nodule diameters were compared between the two protocols.

Results: ULDCT reduced radiation dose by 83% compared to SDCT (1.10 ± 0.22 mSv vs 6.55 ± 1.51 mSv, P < 0.001) while maintaining excellent image quality. SDCT detected 856 nodules, with ULDCT identifying 779 true-positive nodules. Subtype analysis revealed sensitivities of 99.65% for solid nodules, 100% for mixed ground-glass nodules, and 70.12% for pure ground-glass nodules. No significant differences were observed in nodule diameter measurements between ULDCT and SDCT (P > 0.05).

Conclusions: Tin-filtered 150 kV ULDCT achieves high sensitivity for pulmonary nodule detection with significantly reduced radiation dose and maintain clinically acceptable image quality.

Advances in knowledge: This study provides clinical validation of tin-filtered 150 kV ULDCT in a heterogeneous outpatient population, demonstrating its feasibility for accurate pulmonary nodule detection beyond screening settings and highlighting its subtype-specific performance.

Background and purpose: Deep inspiration breath-hold (DIBH) is commonly used in breast cancer radiotherapy to reduce radiation exposure to the heart and lungs. Recent techniques incorporating oxygen supplementation and hyperventilation have enabled DIBHs exceeding 2.5 minutes. However, data on internal organ st ability during prolonged breath-holds (L-DIBH) remain limited.

Materials and methods: In this prospective observational physiological study, ten healthy female volunteers performed two L-DIBHs (2 minutes 8 seconds each) in both prone and supine positions, following a validated hyperventilation and oxygenation protocol. Serial 3D MRI scans were acquired every 16 seconds during each L-DIBH to assess positional stability of the heart, lungs, and left-sided breast. Cumulative distance-volume histograms (cDiVHs) were used to evaluate spatial relationships between organs and quantify internal displacement over time.

Results: 319 high-quality 3D MRI series were analysed. cDiVHs demonstrated consistent organ positions across timepoints and sessions. While left breast position remained stable throughout all L-DIBHs, minor but statistically significant heart displacement was observed during each L-DIBH increasing over time, more pronounced in the prone position than supine.

Conclusion: L-DIBHs of 2 minutes and 8 seconds are achievable and demonstrate stability in left breast positioning, with minimal movement of adjacent internal organs. Small but progressive shifts of the portion of the heart nearest the breast were detected, particularly in prone positioning.

Advances in knowledge: To account for these minimal displacements during L-DIBH, asymmetrical safety margins around the heart of 3 mm in prone and 2 mm in supine positions may be appropriate.

Objectives: This study evaluated the effectiveness of whole-volume apparent diffusion coefficient (ADC) histogram analysis for stratifying renal allograft function.

Methods: A retrospective analysis included 85 renal transplant recipients with ADC measurements from May 2019 to February 2024. They were divided into three groups based on estimated glomerular filtration rate (eGFR): normal graft function (nRAF, eGFR > 60 mL/min/1.73 m2), mild to moderate graft injury (mRAI, 30 mL/min/1.73 m2≤eGFR ≤ 60 mL/min/1.73 m2), and severe allograft injury (sRAI, eGFR < 30 mL/min/1.73 m2). Receiver operating characteristic (ROC) analysis compared the ability of histogram features to differentiate these groups. Correlations between time since transplantation and histogram features were also evaluated.

Results: Sixteen ADC-based histogram features were extracted. Eight parameters were valuable for assessing renal dysfunction (|r|≥0.3, P < 0.05). Seven parameters-ADCmean and Percentiles (10th, 25th, 50th, 75th, 90th, and 95th)-differed significantly between nRAF and sRAI (P < 0.05), with the 50th percentile yielding the largest area under the curve (AUC = 0.785; 95% CI: 0.624-0.928). Two parameters (10th and 25th percentiles) differed significantly between nRAF and mRAI (P < 0.05), with the 10th percentile achieving the largest AUC (0.684; 95% CI: 0.560-0.808). The 10th percentile was negatively correlated with time since transplantation.

Conclusions: ADC-based histogram analysis effectively stratifies renal allograft function and can be used for long-term monitoring of kidney transplant patients in clinical practice.

Advances in knowledge: This study shows that ADC-based histogram analysis can distinguish different degrees of renal allograft dysfunction and is sensitive to early and chronic renal function changes. It offers a non-invasive method for long-term monitoring of kidney transplant patients.