British Journal of Radiology最新文献

Objectives: FLASH radiotherapy (FLASH-RT), characterized by ultra-high dose rate irradiation (>40 Gy/s), has demonstrated the potential to spare normal tissues while maintaining tumour control. Most proton and electron FLASH studies have focused on whole-organ irradiation, and the normal tissue-sparing effects of high-dose proton FLASH-RT in localized thoracic settings remain unclear.

Methods: A preclinical mouse model was developed to evaluate localized high-dose (60 Gy) proton FLASH irradiation to the left lung using spot-size transmission at FLASH (500 Gy/s) or conventional (2 Gy/s) dose rates. Lung and skin responses were assessed by histology, flow cytometry, and enzyme-linked immunosorbent assays.

Results: FLASH-irradiated lungs exhibited decreased pneumonitis and fibrosis compared to conventional irradiation, with faster resolution of tissue damage. Skin toxicity, including epidermal thickening and dermal fibrosis, was significantly reduced after FLASH-RT. At the molecular level, FLASH-RT reduced oxidative stress and inflammatory injury, demonstrated by lower Nrf2 activation, reduced 8-OHdG levels, and decreased MPO expression. Systemically, FLASH-RT led to lower neutrophil-to-lymphocyte ratios and decreased serum IL-6, TNF-α, and IFN-γ, indicating reduced inflammation.

Conclusions: Our findings provide the first evidence that proton FLASH-RT at ablative dose levels (>60 Gy) confers localized protection against radiation-induced lung and skin injury in a preclinical setting. These results support the potential of high-dose proton FLASH-RT for thoracic application, though further studies are needed to establish dose-response relationships and optimize clinical beam configurations.

Advances in knowledge: High-dose proton FLASH-RT preserves lung and skin, and mitigates oxidative and inflammatory responses, offering insights into mechanisms underlying the FLASH effect.

Objective: To evaluate solid volume ratio (SVR) in predicting long-term postoperative outcomes in lung adenocarcinoma patients.

Methods: This study retrospectively analysed the clinical, pathological, and CT data of patients with lung adenocarcinoma who underwent surgical resection and were pathologically confirmed in the Department of Thoracic Surgery of our hospital from June 2014 to June 2023. Multivariate COX analysis was also conducted to identify independent factors that affect treatment effect. P < .05 was considered statistically significant.

Results: A total of 154 patients (82 males and 72 females) were included in this study. The average age was 62.11 ± 8.74 years. There were 60 patients (38.96%) who smoked, and 63 patients (40.90%) had positive pleural invasion. The 3-year disease-free survival (DFS) rate and overall survival (OS) rate after surgical resection were 87.5% and 92.0%, respectively; the 5-year DFS rate and OS rate after surgical resection were 81.6% and 89.1%, respectively. Multiple COX regression analysis showed that gender (P = .009, odds ratio [OR]: 4.197, 95% confidence interval [CI]: 1.426-12.353), and the solid volume ratio (P = .004, OR: 1.021, 95% CI: 1.007-1.036) were identified as an independent predictor of recurrence. Multivariate COX analysis showed that SVR (P = .003, OR: 1.028, 95% CI: 1.009-1.046) was identified as an independent predictor of postoperative survival in patients with lung cancer.

Conclusion: In this study, compared with consolidation tumour rate (CTR), the SVR has certain value in evaluating the therapeutic efficacy of lung adenocarcinoma.

Advances in knowledge: SVR is an independent predictor of postoperative recurrence and survival in lung cancer, and provides new ideas for postoperative efficacy evaluation.

Objectives: We evaluated whether automated CT-based adiposity tools can predict all-cause mortality in a large retrospective adult population.

Methods: This study included 151 177 patients who underwent abdominal CT between 2000 and 2021. An AI-based algorithm measured abdominal visceral adipose tissue (VAT) cross-sectional area and density at the L3. Kaplan-Meier survival curves and hazard ratios assessed VAT and mortality.

Results: Among 136 895 patients included, 9059 died within 1 year and 18 829 died within 2 to 20 years post-CT. Higher VAT density predicted 1-year mortality (hazard ratio [HR] up to 3.8) and over 2-20 years (HR up to 2.1). In contrast, VAT area did not significantly predict mortality. High VAT density was associated with the poorest survival, regardless of area. Low VAT density predicted better survival, regardless of area. VAT density consistently predicted mortality across age groups and sexes, whereas BMI did not differentiate risk.

Conclusions: AI-enabled CT measures of VAT density are superior to VAT area for predicting all-cause mortality. Furthermore, we analysed VAT density vs. BMI in our largest age group (40-59) and found BMI was unable to adequately predict risk of mortality. Automated assessment of VAT density may enhance patient risk assessment and management.

Advances in knowledge: Assessing visceral fat density using fully automated AI-based CT tools offers a significant advancement in predicting health risk, leading to targeted interventions and improved management strategies. This study is novel due to its large patient population, offering evidence that prognostication with VAT density is broadly generalizable across varying patient populations.

Accurate evaluation of myocardial ischaemia is critical for the management of coronary artery disease (CAD). Quantitative perfusion cardiovascular magnetic resonance (QP-CMR) provides high-resolution assessment of absolute myocardial blood flow (MBF) without ionising radiation. It has demonstrated excellent diagnostic performance for detecting haemodynamically significant CAD, often outperforming visual analysis, particularly in the setting of multi-vessel disease. Similarly, quantitative computed tomography perfusion (CTP) integrates coronary anatomy with functional data and has been shown to significantly improve diagnostic accuracy and specificity over coronary CT angiography alone. This review provides an overview of quantitative myocardial perfusion imaging using CMR and cardiac CT, including their fundamental principles and diagnostic performance. Furthermore, we explore their expanding clinical applications beyond epicardial CAD, such as the evaluation of coronary microvascular dysfunction and non-ischaemic cardiomyopathies, and discuss their advantages and limitations as well as future directions.

Objective: To evaluate ultrasound's diagnostic value for full-thickness supraspinatus tendon (SST) tears and correlate it with arthroscopy findings.

Methods: In this retrospective study, patients with a clinical diagnosis of rotator cuff tears were included. The inclusion criteria were patients with shoulder joint pain and limited shoulder mobility. The exclusion criteria comprised patients who had undergone any previous shoulder surgery or those with shoulder fractures or dislocations. Ultrasound imaging features were observed and recorded, including measurements of the length and width of tears to reveal tear patterns. The chi-square test was used to compare the clinical characteristics of categorical variables, and the Wilcoxon test was used to assess the correlation between ultrasound and arthroscopy.

Results: From January 2023 to November 2023, 105 patients diagnosed with rotator cuff tears were included (50 males, 55 females, mean age 67.9 ± 14.2 years). Arthroscopy confirmed full-thickness SST tears in 82 patients (78.1%). Ultrasound demonstrated differential diagnostic performance across tear patterns: sensitivity/specificity 90.0%/95.8%(crescent), 93.1%/94.3% (U-shaped), 83.8%/98.0% (L-shaped), and 100%/98.6% (giant), with corresponding area under the ROC curves (AU-ROCs) of 0.789-0.882. Significant correlations were observed between ultrasound and arthroscopic measurements, particularly for crescent-type tear width (r = 0.949, p < 0.001).

Conclusion: Ultrasound effectively distinguishes SST tear types, with high concordance to arthroscopy, supporting its use as a primary imaging tool for surgical planning in rotator cuff pathology.

Advances in knowledge: Ultrasound has significant application value in the diagnosis of full-thickness of SST tears. Ultrasound shows high consistency with arthroscopic findings and can effectively differentiate various tear patterns.

Omics imaging has emerged as an interdisciplinary field focused on integrating data collected from biomedical images and omics analysis. Historically, there is precedent for omics imaging to serve as a superior model for prediction of human diseases, including brain disorders and cancer, versus single technique models (e.g., only imaging data or only omics data). Most of the previous studies in the field of omics imaging have focused on single organ analysis. However, the advent of total-body Positron Emission Tomography (PET) imaging for clinical use has the potential to transform this landscape by enabling high sensitivity or high throughput multi-organ analysis with methodologies previously established for analysis of omics datasets, such as connectome and pathway analysis tools. Conversely, traditional omics analysis, which lack spatial and structural multi-organ information, can benefit from total-body PET imaging of molecular targets in vivo across multiple organs in humans. In this commentary, the importance of whole-person research enabled by total-body PET, integration of total-body PET with omics techniques and examples successful case studies of imaging omics are described. Although the field of imaging omics is relatively new, discoveries already enabled by this field provide seminal evidence of its importance to advance human disease diagnosis, prognosis and treatment.

Objectives: This study assessed the impact of a structured quantitative analysis program on diagnostic performance, interrater reliability, and reader confidence in interpreting N-3-[18F]fluoropropyl-2β-carbomethoxy-3β-4-iodophenyl nortropane positron emission tomography ([18F]FP-CIT PET) scans to differentiate idiopathic Parkinson's disease from essential tremor-/drug-induced parkinsonism.

Methods: This retrospective multicentre study included 637 patients who underwent [18F]FP-CIT PET and brain magnetic resonance imaging scans for evaluation of Parkinsonian syndromes at 4 institutions between January 2015 and October 2022. Readers evaluated the scans qualitatively in the pre-program session and with access to quantitative parameters in the post-program session, with a 1-month minimum interval to minimize recall bias. Diagnostic performance metrics (sensitivity, specificity, accuracy), interrater reliability (Cohen's κ), and reader confidence (low/moderate vs. high) were compared.

Results: Following program implementation, interrater reliability significantly improved from substantial to almost perfect (Cohen's κ: 0.768 to 0.970; p < 0.001), and a significant shift toward high-confidence ratings was observed (p < 0.001). Diagnostic accuracy also significantly improved from 92.8% to 94.3% (p = 0.036). Although the increase in the area under the curve (0.922 to 0.932) did not reach statistical significance (p = 0.163), likely due to a ceiling effect, reader performance significantly surpassed that of the quantitative parameter alone only after program implementation, whereas it was comparable at baseline.

Conclusions: These findings suggest that integrating quantitative analysis tools may improve diagnostic consistency and reliability in clinical practice.

Advances in knowledge: The structured quantitative analysis program significantly improved [18F]FP-CIT PET/CT interpretation by increasing diagnostic accuracy, interrater reliability, and reader confidence.

Objectives: To evaluate the diagnostic performance of [68Ga]Ga-FAPI PET/CT-derived metabolic parameters in thyroid nodules and their association with cytological risk stratification, with particular emphasis on indeterminate nodules.

Methods: Forty patients with 53 thyroid nodules who underwent [68Ga]Ga-FAPI PET/CT were prospectively analyzed. Maximum standardized uptake value and tumor-to-background ratio were calculated for each nodule. Ultrasound-based malignancy classification and Bethesda cytology categories were recorded. Comparisons between benign and malignant nodules were performed in the overall cohort (Bethesda I-VI) and within the Bethesda III-IV subgroup. Multivariable logistic regression was used to identify independent predictors of malignancy. Diagnostic performance was assessed using receiver operating characteristic analysis.

Results: In the overall cohort, SUVmax and TBR were significantly higher in malignant nodules than in benign nodules (p < 0.01). In multivariable analysis, TBR showed a stronger independent association with malignancy, whereas USG-BM was not independently predictive. Within the Bethesda III-IV subgroup, SUVmax and TBR did not differ significantly in univariable analyses; however, TBR demonstrated a borderline independent association with malignancy in multivariable analysis (p = 0.058). SUVmax and TBR values were significantly higher in Bethesda V-VI nodules compared with Bethesda III-IV nodules (both p < 0.001). ROC analysis demonstrated good discriminative performance for both parameters, with TBR yielding a higher area under the curve and high negative predictive values.

Conclusion: [68Ga]Ga-FAPI PET/CT-derived metabolic parameters, particularly TBR, show promising diagnostic performance for thyroid nodule characterization. High negative predictive values suggest a potential complementary role for excluding malignancy, especially in indeterminate nodules. Further multicenter studies are warranted.

Advances in knowledge: [68Ga]Ga-FAPI PET/CT-derived metabolic parameters were higher in malignant thyroid nodules compared with benign lesions. These findings suggest that FAPI PET/CT may provide complementary functional information in nodules with indeterminate cytology.

Objectives: To evaluate the influence of fat on the assessment of liver fibrosis in chronic liver disease using two-point Dixon water-only Look-Locker T1 mapping by comparing water-only derived sequence (W-Dixon) with in-phase (IP) and opposed-phase (OP)-based sequences.

Methods: 2.89-T MRI included 2D two-point Dixon Look-Locker T1 mapping and proton density fat fraction (PDFF) mapping. The correlations between liver T1 values and PDFF were assessed using Spearman correlation coefficient. T1 values on each T1 map were compared among three FIB-4 index range groups (FIB-4 < 1.3, 1.3-2.67, > 2.67) in patients with and without hepatic steatosis using one-way analysis of variance and Kruskal-Wallis test.

Results: 204 patients with chronic liver disease were retrospectively evaluated. T1 values on IP or OP images were significantly correlated with PDFF (r = -0.373, 0.220), while no significant correlation was found between T1 values on W-Dixon images and PDFF (r = -0.071). In patients without hepatic steatosis, T1 values on each T1 map in FIB-4 > 2.67 group were significantly higher than in FIB-4 1.3-2.67 group (p < 0.01). Conversely, in patients with hepatic steatosis, only W-Dixon sequence statistically differentiated FIB-4 > 2.67 group from FIB-4 1.3-2.67 group based on T1 values (p < 0.05).

Conclusions: The assessment of liver fibrosis based on T1 values obtained by Dixon water-only T1 mapping was less influenced by the presence of fat.

Advances in knowledge: Two-point Dixon water-only Look-Locker T1 mapping minimizes the confounding effect of fat, enabling proper assessment of liver fibrosis in steatotic chronic liver disease.

Background: This study investigated the anatomical location of non-palpable undescended testes (UTs), which account for approximately 20% of all cases of UTs. Radiological imaging is essential to determine the location of such testes in the abdomen or groin. Other studies have examined the diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) in detecting and localizing non-palpable UTs. However, no study has used apparent diffusion coefficient (ADC) values to differentiate UT tissue.

Methods: This study included consecutive children referred to a pediatric surgery clinic with a prediagnosis of UT. DWI images were used to evaluate lymph node (LN) and testicular tissue. ADC values were measured by placing a circular region of interest at the center.

Results: The study enrolled 44 boys (73 testes) who underwent pelvic MRI. Age and testicular volume were significantly positively correlated (p < 0.001). Testicular ADC values were higher in both inguinal and abdominal locations than in scrotal locations. However, the ADC values of LNs were significantly lower than those of testes. Our ROC analysis revealed that an ADC value < 940 10-3/mm2 could differentiate between LNs and testes (AUC = 0.826, p < 0.001).

Conclusion: Measuring ADCs using a DWI imaging sequence is an accurate method of differentiating between testes and LNs.

Advances in knowledge: This study is the first to show that ADC values from diffusion-weighted MRI can reliably differentiate non-palpable undescended testes from lymph nodes. ADC mapping appears to be a novel and accurate tool for detecting testicular localization when conventional assessment is inadequate.