European Radiology最新文献

Objectives: To compare an MRI-based radiomics signature with the programmed cell death ligand 1 (PD-L1) expression score for predicting immunotherapy response in nasopharyngeal carcinoma (NPC).

Methods: Consecutive patients with NPC who received immunotherapy between January 2019 and June 2022 were divided into training (n = 111) and validation (n = 66) sets. Tumor radiomics features were extracted from pretreatment MR images. PD-L1 combined positive score (CPS) was calculated using immunohistochemistry. The least absolute shrinkage and selection operator (LASSO) algorithm was used for feature selection and radiomics signature construction. Receiver operating characteristic (ROC) curve analysis was performed to assess prediction performance.

Results: A total of eleven radiomics features with the greatest discrimination capability were identified by the LASSO algorithm to construct the radiomics signature. In predicting patients with objective response to immunotherapy, radiomics score (Rd-score) yielded a significantly higher area under the ROC curve than that of CPS in both the training (0.790 vs. 0.645, p = 0.025) and the validation (0.735 vs. 0.608, p = 0.038) sets. Multivariate analysis identified the Rd-score as an independent influencing factor in predicting immunotherapy response (odds ratio = 19.963, p < 0.001). Kaplan-Meier analysis indicated that patients with Rd-score ≥ 0.5 showed longer progression-free survival than patients with Rd-score < 0.5 (log-rank p < 0.01).

Conclusion: An MRI-based radiomics signature demonstrated greater efficacy than the PD-L1 expression score in predicting immunotherapy response in patients with NPC.

Key points: Question How does an MRI-based radiomics signature compare with the programmed cell death ligand 1 expression score for predicting immunotherapy response in nasopharyngeal carcinoma? Findings The MRI-based radiomics signature demonstrated superior predictive value compared with programmed cell death ligand 1 expression score in identifying immunotherapy responders. Clinical relevance MRI-based radiomics are a promising novel noninvasive tool for predicting immunotherapy outcomes in nasopharyngeal carcinoma.

Objective: To investigate the prognostic value of baseline European Association of Nuclear Medicine Research Ltd. (EARL) standardized [¹⁸F]fluorodeoxyglucose positron emission tomography-computed tomography ([¹⁸F]FDG PET-CT) quantitative values for survival and to evaluate cutoff values identified in other studies.

Materials and methods: Pediatric and adolescent patients with high-grade osteosarcoma were included. Baseline [¹⁸F]FDG PET-CT, with EARL-accredited reconstructions, was the standard diagnostic staging procedure. Cox proportional hazard analysis for event-free survival (EFS) and overall survival (OS) was performed with clinical prognostic factors. Kaplan-Meier analysis and log-rank tests were applied to investigate the prognostic performance of the [¹⁸F]FDG PET indices.

Results: In total, 66 patients were included in this study. In the univariable Cox regression analysis, peak lean-body mass corrected SUV (SUL_peak) (hazard ratio (HR): 1.04), total lesion glycolysis (TLG) (HR: 1.0), and metabolic tumor volume (MTV) (HR: 1.0) were not associated with EFS or OS. Log-rank analysis showed a significant difference in EFS for all SUL_max and SUL_peak cutoffs. For MTV_total the maximum Youden, and for TLG_total, the maximum Youden and maximally selected rank cutoff resulted in a significant EFS difference. No cutoff for any measure showed a significant difference in OS between the groups. ROC curves for event status had an AUC of 0.67, 0.66, 0.64, and 0.64 for SUL_max, SUL_peak, MTV_total, and TLG_total, respectively.

Conclusion: In this study, the baseline EARL-standardized [¹⁸F]FDG PET indices of children and adolescents with osteosarcoma were not prognostic of EFS or OS. The proposed prognostic cutoffs from earlier studies suffer from important technical and statistical issues.

Key points: Question Prognostic value of baseline [¹⁸F]FDG PET-CT imaging markers have been reported for histologic response and survival in high-grade osteosarcoma but have not been validated for clinical practice. Findings Baseline SUV_peak, TLG_total, and MTV_total measured on EARL-accredited reconstructions were not prognostic factors for survival in pediatric and adolescent patients with high-grade osteosarcoma. Clinical relevance A wide range of values for SUV_peak and SUV_max cutoffs with similar prognostic value were identified, questioning the value of a single proposed cutoff. Lack of validation, with important technical and statistical issues of proposed prognostic cutoffs, limits clinical implementation.

Objectives: An increasing number of patients with prostate cancer (PCa) undergo assessment with magnetic resonance imaging (MRI) and prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT). This offers comprehensive multimodality staging but can lead to discrepancies. The objective was to assess the rates and types of discordance between MRI and PSMA-PET/CT for primary PCa assessment.

Materials and methods: Consecutive men diagnosed with intermediate and high-risk PCa who underwent MRI and PSMA-PET/CT in 2021-2023 were retrospectively included. MRI and PSMA-PET/CT were interpreted using PI-RADS v2.1 and PRIMARY scores. Discordances between the two imaging modalities were categorized as "minor" (larger or additional lesion seen on one modality) or "major" (positive on only one modality or different index lesions between MRI and PSMA-PET/CT) and reconciled using radical prostatectomy or biopsy specimens.

Results: Three hundred and nine men (median age 69 years, interquartile range (IQR) 64-75) were included. Most had Gleason Grade Group ≥ 3 PCa (70.9% (219/309)). Median PSA was 9.0 ng/mL (IQR 5.6-13.6). MRI and PSMA-PET/CT were concordant in 157/309 (50.8%) and discordant in 152/309 (49.1%) patients; with 39/152 (25.7%) major and 113/152 (74.3%) minor discordances. Of 27 patients with lesions only seen on MRI, 85.2% (23/27) were clinically significant PCa (csPCa). Of 23 patients with lesions only seen on PSMA-PET/CT, 78.3% (18/23) were csPCa. Altogether, lesions seen on only one modality were csPCa in 80.0% (36/45).

Conclusion: MRI and PSMA-PET/CT were discordant in half of patients for primary PCa evaluation, with major discrepancies seen in roughly one out of eight patients.

Key points: Question While both MRI and PSMA-PET/CT can be used for primary tumor assessment, the discordances between them are not well established. Findings MRI and PSMA-PET/CT were discordant in about half of the patients. Most prostate lesions seen on only one modality were significant cancer. Clinical relevance MRI and PSMA-PET/CT are often discordant for assessing the primary prostate tumor. Using both modalities for primary prostate tumor evaluation can provide complementary information that may substantially impact treatment planning.

Objectives: To determine whether plaque composition analysis defined by cardiac CT can provide incremental prognostic value above coronary artery disease (CAD) burden markers in symptomatic patients with obstructive CAD.

Materials and methods: Between 2009 and 2019, a multicentric registry included all consecutive symptomatic patients with obstructive CAD (at least one ≥ 50% stenosis on CCTA) and was followed for major adverse cardiovascular (MACE) defined by cardiovascular death or nonfatal myocardial infarction. Each coronary segment was scored visually for both the degree of stenosis and composition of plaque, which were classified as non-calcified, mixed, or calcified. To assess the prognostic value of each CCTA findings, different multivariable Cox regression models were used: model 1: clinical (traditional risk factors); model 2: model 1 + CAD burden (number of proximal segments with stenosis ≥ 50% + number of vessels with obstructive CAD); and model 3: model 2 + plaques feature (number of segments with non-calcified plaque).

Results: Of 2312 patients (mean age 70 ± 12 years, 46% men), 319 experienced a MACE (13.8%) (median follow-up: 6.7 years (5.9-9.1)). The number of proximal segments with ≥ 50% stenosis, the number of vessels with obstructive CAD, and the number of segments with non-calcified plaque were all independently associated with MACEs (all p < 0.001). The addition of plaque composition analysis (model 3) showed the best improvement in model discrimination and reclassification (C-statistic improvement = 0.03; net reclassification improvement = 28.6%; integrative discrimination index = 5.4%, all p < 0.001).

Conclusions: In this population, the analysis of coronary plaque composition had an incremental prognostic value to predict MACEs above a model combining traditional risk factors and CAD burden.

Key points: Question Several coronary computed tomography angiography (CCTA) studies have shown the potential interest of plaque composition analysis, which can be further evaluated. Findings In symptomatic patients with obstructive coronary artery disease (CAD), plaque composition analysis had an incremental prognostic value above a model combining traditional risk factors and CAD burden. Clinical relevance In symptomatic patients with obstructive CAD, plaque composition analysis using CCTA has a strong incremental prognostic value above a model combining traditional risk factors and CAD burden, thus translating into a more accurate long-term major adverse cardiovascular event prediction.

Objectives: To assess glymphatic function and white matter integrity in children with autism spectrum disorder (ASD) using multi-parametric MRI, combined with machine learning to evaluate ASD detection performance.

Materials and methods: This retrospective study collected data from 110 children with ASD (80 exploratory, 43 validation) and 68 typically developing children (50 exploratory, 18 validation) from two centers. The automated diffusion tensor imaging along the perivascular space (aDTI-ALPS), fractional anisotropy (FA), cerebrospinal fluid volume, and perivascular space (PVS) volume indices were extracted from DTI, three-dimensional T1-weighted, and T2-weighted images. Intergroup comparisons were conducted using t-tests, Mann-Whitney U-test, and tract-based spatial statistics. Correlation analysis assessed the relationship between glymphatic function, white matter integrity, and clinical scales. Machine learning models based on MRI indices were developed using the AutoGluon framework.

Results: The PVS volume (p < 0.001) was larger, and aDTI-ALPS index (p < 0.001) was lower in children with ASD compared to typically developing children. FA values were reduced in the ASD group and positively correlated with aDTI-ALPS index. The aDTI-ALPS index correlated with ASD severity (r = -0.27, p = 0.02) and developmental delays (r = 0.63, p < 0.001). Mediation analysis indicated the aDTI-ALPS index partially mediated the relationship between white matter integrity and developmental delay. The MRI-based model achieved an area under the curve of 0.84 for ASD diagnosis.

Conclusion: Analyzing glymphatic function and white matter integrity enhances understanding of ASD's neurobiological underpinnings. The multi-parametric MRI, combined with machine learning, can facilitate the early detection of ASD.

Key points: Question How can multi-parametric MRI based on the glymphatic system improve early diagnosis of autism spectrum disorder (ASD) beyond the limitations of current behavioral assessments? Findings Glymphatic dysfunction and disruptions in white matter integrity were associated with clinical symptoms of ASD. Multi-parametric MRI with machine learning can improve early ASD detection. Clinical relevance Multi-parametric MRI, focusing on glymphatic function and white matter integrity, enhances the diagnostic accuracy of ASD by serving as an objective complement to clinical scales.

Objective: The purpose of this study was to explore microvascular function impairment using first-pass cardiovascular magnetic resonance (CMR) in patients with Takotsubo syndrome (TS). Moreover, we explored myocardial microcirculation in patients with TS and related this to demographic data, cardiovascular risk factors, clinical parameters, cardiac biomarkers, and cardiac function.

Methods: This retrospective study performed CMR first-pass perfusion scans in 42 consecutive patients with TS (37 females, 70.6 ± 9.4 years). Moreover, we included 44 sex- and age-matched healthy controls (33 females, 66.4 ± 10.5 years). CMR-derived myocardial microcirculation function was analyzed and compared between TS patients and controls.

Results: Compared to age-, sex-, and cardiovascular risk factors-matched control group, TS patients demonstrated a lower perfusion index (PI) (0.140 ± 0.060 vs. 0.182 ± 0.056, p = 0.001). In multivariable analysis with adjustment for demographic data and cardiovascular risk factors, an impairment in PI was independently associated with left ventricle ejection fraction (β coefficient = 3.793, p = 0.001) and T2 mapping (β coefficient = -4.316, p = 0.001).

Conclusion: TS patients exhibited myocardial microvascular dysfunction, which was non-invasively assessed using first-pass CMR. This impaired myocardial microvascular function was found to be independently associated with left ventricular ejection fraction and myocardial edema.

Key points: Question Can cardiovascular magnetic resonance (CMR) cardiac MR first-pass perfusion help to better understand Takotsubo pathophysiology by exploring microvascular impairment? Findings CMR first-pass perfusion revealed significant microvascular dysfunction during the acute phase of Takotsubo syndrome, independently associated with left ventricular ejection fraction and myocardial edema. Clinical relevance Identifying an abnormal microvascular network using non-invasive biomarkers could enhance risk stratification and guide tailored management during the acute phase of Takotsubo syndrome.

Objectives: Brain metastases are the most common intracranial malignancy in adults, and their detection is crucial for treatment planning. Post-contrast 3D T1 gradient-recalled echo (GRE) sequences are commonly used for this purpose, but contrast-enhanced 3D T1 turbo spin-echo (TSE) sequences with motion-sensitized driven-equilibrium (MSDE) technique ("black blood") may offer improved detection. This study aimed to compare the effectiveness of contrast-enhanced 3D black blood sequences to standard 3D T1 GRE sequences in detecting brain metastases on a 1.5-T MRI.

Materials and methods: A retrospective analysis of 183 patients with suspected or follow-up brain metastases between May 2022 and September 2023 was conducted. Among these patients, 107 were included in the final analysis. Both post-contrast 3D T1 GRE and 3D black blood sequences were acquired on the same scanner with similar acquisition times. Two neuroradiologists independently evaluated the images for the number, size, and location of metastases. Interobserver variability and statistical analysis were performed.

Results: Among the 107 patients (mean age 60.8 years ± 13.2 years; 55 males, 52 females), 3D black blood sequences detected a significantly higher number of brain metastases, particularly small lesions (< 5 mm), compared to 3D T1 GRE sequences (p < 0.05). There was no significant difference in detecting large metastases (≥ 5 mm) between the sequences. In addition, the black blood sequences provided better conspicuity of metastases in the majority of patients (85%).

Conclusion: Contrast-enhanced 3D T1 TSE with MSDE ("black blood") sequences offer improved detection of brain metastases, especially small lesions, on 1.5-T MRI compared to standard 3D T1 GRE sequences.

Key points: Question Accurate identification of the number and location of brain metastases using MRI is essential for planning and managing effective treatment. Findings Contrast-enhanced 3D T1 TSE black blood sequences detected significantly more small brain metastases than standard 3D T1 GRE sequences on 1.5-T MRI. Clinical relevance The use of 3D black blood sequences on 1.5-T MRI may have the potential to improve the accuracy of detection of brain metastases, leading to better treatment planning and potentially improved patient outcomes.

Objectives: Evaluating the impact of an AI-based automated cardiac MRI (CMR) planning software on procedure errors and scan times compared to manual planning alone.

Material and methods: Consecutive patients undergoing non-stress CMR were prospectively enrolled at a single center (August 2023-February 2024) and randomized into manual, or automated scan execution using prototype software. Patients with pacemakers, targeted indications, or inability to consent were excluded. All patients underwent the same CMR protocol with contrast, in breath-hold (BH) or free breathing (FB). Supervising radiologists recorded procedure errors (plane prescription, forgotten views, incorrect propagation of cardiac planes, and field-of-view mismanagement). Scan times and idle phase (non-acquisition portion) were computed from scanner logs. Most data were non-normally distributed and compared using non-parametric tests.

Results: Eighty-two patients (mean age, 51.6 years ± 17.5; 56 men) were included. Forty-four patients underwent automated and 38 manual CMRs. The mean rate of procedure errors was significantly (p = 0.01) lower in the automated (0.45) than in the manual group (1.13). The rate of error-free examinations was higher (p = 0.03) in the automated (31/44; 70.5%) than in the manual group (17/38; 44.7%). Automated studies were shorter than manual studies in FB (30.3 vs 36.5 min, p < 0.001) but had similar durations in BH (42.0 vs 43.5 min, p = 0.42). The idle phase was lower in automated studies for FB and BH strategies (both p < 0.001).

Conclusion: An AI-based automated software performed CMR at a clinical level with fewer planning errors and improved efficiency compared to manual planning.

Key points: Question What is the impact of an AI-based automated CMR planning software on procedure errors and scan times compared to manual planning alone? Findings Software-driven examinations were more reliable (71% error-free) than human-planned ones (45% error-free) and showed improved efficiency with reduced idle time. Clinical relevance CMR examinations require extensive technologist training, and continuous attention, and involve many planning steps. A fully automated software reliably acquired non-stress CMR potentially reducing mistake risk and increasing data homogeneity.

Objective: Metastatic castration-resistant prostate cancer (mCRPC) is a heterogeneous disease with varying survival outcomes. This study investigated whether baseline PSMA PET/CT parameters are associated with survival and treatment response.

Methods: Sixty mCRPC patients underwent [¹⁸F]PSMA-1007 PET/CT before treatment with androgen receptor-targeted agents (ARTAs) or chemotherapy. Intensity-based parameters, volumetric parameters, metastatic sites and DmaxVox (distance between the two outermost voxels) from baseline PSMA PET/CT were collected, as well as age, Gleason score and laboratory parameters. Cox regression analysis evaluated their prognostic value for overall survival (OS). Additionally, a preliminary lesion-level analysis was done (n = 241 lesions) with lesion location and twelve radiomic features selected from previous literature. Logistic regression evaluated their association with PSMA PET/CT-based lesion progression after 3-4 months of treatment.

Results: Total tumour volume (PSMA-TV) (HR = 1.41 per doubling [1.17-1.70]), total lesion uptake (TL-PSMA) (HR = 1.40 per doubling [1.16-1.69]) and DmaxVox (HR = 1.31 per 10 cm increase [1.07-1.62]) were prognostic for OS, each independent of baseline PSA level (HR = 0.82 per doubling [0.68-0.98]), haemoglobin level (HR = 0.68 per mmol/L increase [0.49-0.95]) and line of treatment. On lesion-level, location (prostate vs bone OR = 0.23 [0.06-0.83]) and SUV_mean (OR = 1.72 per doubling [1.08-2.75]) were independent prognostic markers for lesion progression, morphological and texture-based radiomic features were not.

Conclusion: Baseline PSMA PET/CT scans have prognostic value in mCRPC patients and can potentially aid in treatment decision-making. DmaxVox can serve as a simpler alternative to PSMA-TV when automated segmentation software is not available. When combined with PSMA-TV, lower PSA levels indicated worse OS, which may be a marker of tumour dedifferentiation. Further research is needed to validate these models in larger patient cohorts.

Key points: Question mCRPC is a highly heterogeneous disease, requiring good prognostic markers. Findings PSMA-TV was the best independent prognostic marker for OS; maximum distance between lesions (DmaxVox) can be used as a simpler alternative. Clinical relevance Baseline PSMA PET/CT parameters representing tumour burden were independently associated with OS in mCRPC patients, providing prognostic insights for clinical decision-making. Although PSMA-TV was the best prognostic marker, DmaxVox can serve as an easier to obtain alternative.