Background The grading system for invasive lung adenocarcinoma proposed by the International Association for the Study of Lung Cancer (IASLC) has been widely validated. However, the association of PET/CT with IASLC grade and its value in clinical decision-making is unknown. Purpose To investigate the association of PET/CT metabolic parameters with IASLC grade and determine the complementary clinical value of PET/CT in optimizing preoperative surgical decision-making in clinical stage IA (cIA) lung adenocarcinoma. Materials and Methods This retrospective study included consecutive patients who underwent preoperative PET/CT and complete resection for cIA lung adenocarcinoma between September 2020 and March 2022. Logistic regression was used to identify predictors of grade 3 lung adenocarcinoma. Multivariable Cox models assessed prognostic effects and interactions between maximum standardized uptake value (SUVmax) and surgical strategy. Propensity score matching was used to balance clinicopathologic characteristics across surgical strategies. Results The study included 2789 patients (median age, 62 years [IQR, 55-68 years]; 1574 women). Logistic regression analysis demonstrated a positive interaction between radiologic type and SUVmax (P = .008) in predicting grade 3 adenocarcinoma. Specific cutoff values for pure solid (cutoff of 4.25) and subsolid (cutoff of 2.30) nodules were identified. Positive interactions between SUVmax and surgery were observed exclusively in pure solid nodules (SUVmax-resection extent for overall survival [OS], P = .048; SUVmax-nodal dissection for OS, P = .045). Stratified analyses showed that segmentectomy and limited lymph node dissection were associated with worse outcomes only in hypermetabolic lesions (SUVmax > 4.25; resection extent hazard ratio [HR] for OS, 2.06 [P = .03]; nodal dissection HR for OS, 2.06 [P = .005]). SUVmax maintained robust predictive efficacy for grade 3 lung adenocarcinoma in the external cohort (area under the receiver operating curve, 0.72 for pure solid nodules and 0.74 for subsolid nodules). Conclusion In patients who underwent PET/CT and complete resection for clinical stage IA lung adenocarcinoma, maximum standardized uptake value was an independent predictor of grade 3 lung adenocarcinoma and helped identify high-risk patients treated with segmentectomy or limited nodal dissection. © RSNA, 2026 Supplemental material is available for this article.

Background The clinical utility of quantitative T1 mapping in cardiac MRI is constrained by variability across acquisition protocols, and a comprehensive comparison between commonly used sequences remains unavailable. Purpose To provide a full range of cardiac MRI native T1 and extracellular volume fraction (ECV) values at 3 T in healthy Chinese adults and participants with various cardiovascular diseases and, as a secondary aim, to establish the relationship between modified Look-Locker inversion recovery (MOLLI) and shortened MOLLI (ShMOLLI) measurements. Materials and Methods This prospective study included healthy volunteers, participants with normal cardiac MRI findings, and participants representing 13 cardiovascular conditions. All participants underwent 3-T cardiac MRI with both MOLLI and ShMOLLI sequences during a single examination. Global native T1 and ECV values were quantified and compared between sequences and across disease groups. Statistical approaches included t tests, Pearson correlation, Bland-Altman analysis, and Cohen D standardization. Results This study included 1237 clinical participants (mean age ± SD: 51 years ± 14.8; 854 men). Reference values (adjusted mean ± SE) in healthy volunteers were 1170 msec ± 9 (MOLLI) and 1135 msec ± 10 (ShMOLLI) for native T1 and were 24.8% ± 0.6 (both MOLLI and ShMOLLI) for ECV, with women showing higher native T1 values than men (all P ≤ .002). MOLLI yielded systematically higher native T1 than ShMOLLI across all conditions (mean difference: 46.0 msec ± 27.2; all P < .01), whereas ECV did not differ for most conditions (10 of 15 groups; P > .05). Strong intersequence correlations were observed for native T1 (Pearson r = 0.93; P < .001) and ECV (r = 0.95; P < .001). After standardization to sequence-specific baselines, pathologic deviations were comparable between sequences (Cohen D differences ≤0.5 in most groups). A supplementary swine study supported the technical validity of both sequences (r = 0.87-0.90; P < .001). Conclusion In participants who underwent 3-T cardiac MRI with both MOLLI and ShMOLLI sequences, native T1 was higher with MOLLI than ShMOLLI, but ECV was consistent across sequences. © RSNA, 2026 Supplemental material is available for this article. See also the editorial by Dacher and Cadour in this issue.

Women with extremely dense breasts have an increased risk of breast cancer but also a decreased sensitivity of mammography. The Dense Tissue and Early Breast Neoplasm Screening (DENSE) trial, initiated in 2011, showed that supplemental full-protocol MRI screening reduced the number of interval cancers in women with extremely dense breasts. Cost-effective screening scenarios have been described, but imaging costs and capacity remain barriers to implementing full-protocol MRI in population-based breast cancer screening programs. Therefore, the DENSE-2 trial was set up to investigate two alternate screening techniques, contrast-enhanced mammography (CEM) or abbreviated MRI (AB-MRI), that are expected to be cheaper and to make more efficient use of the available capacity while potentially achieving similar results to full-protocol MRI. DENSE-2 is a multicenter randomized controlled trial embedded in the Dutch screening program. It comprises two consecutive screening rounds in which women receive the same breast imaging technique both times. The trial investigates the value of supplemental screening with CEM or AB-MRI in women with extremely dense breasts with a negative screening mammogram. The primary aim is to determine whether these methods will lead to a reduction of interval cancers compared with mammography. The DENSE-2 trial results will provide insights into the performance, feasibility, and acceptability of both screening modalities, enable long-term outcome modeling, and support decision-making on the most appropriate screening strategy for women with extremely dense breasts. ClinicalTrials.gov: NCT06636370 © RSNA, 2026 Supplemental material is available for this article. See also the editorial by Bahl in this issue.

Background Artificial intelligence (AI) systems have demonstrated non-inferiority to radiologists for prostate cancer detection on MRI, but evidence in global diagnostic and population-based screening settings remains limited. Purpose To determine whether an AI system can achieve diagnostic performance comparable to radiology readings for detecting Gleason grade group ≥2 prostate cancer on MRI in external diagnostic and screening datasets. Materials and Methods In the SCARLET-1 retrospective validation study, prostate MRIs from adults with suspected prostate cancer (January 2012-October 2024) were used to evaluate an AI system, with external testing in diagnostic (PRIME) and organized screening settings (STHLM3-MRI and IP1-PROSTAGRAM). The primary outcome was agreement between AI assessments and standard-of-care diagnoses of Gleason grade group ≥2 cancer, with diagnostic interchangeability defined relative to the estimated agreement of an average radiologist. Secondary outcomes included area under the receiver operating characteristic curve (AUC) across datasets and subgroups. Results 22,445 examinations (21,252 male patients; median age, 66 years [IQR 60-71]) were included: 20,471 prostate MRI examinations (19,278 patients; 26 cities, 14 countries) for AI training and internal testing, and 1974 patients (20 external cities, 12 countries) for external testing. External AUCs were 0.86 (95% CI: 0.83, 0.90) in PRIME, 0.89 (95% CI: 0.86, 0.92) in STHLM3-MRI, and 0.84 (95% CI: 0.70, 0.95) in IP1-PROSTAGRAM. The primary outcome was 83.0% (395 of 476; adjusted 95% CI: 78.8%, 87.0%), 87.9% (974 of 1108; adjusted 95% CI: 85.6%, 90.3%), and 87.7% (342 of 390; adjusted 95% CI: 83.6%, 91.5%), respectively, meeting prespecified interchangeability criteria in all datasets. Subgroup performance was consistent across age, risk, cancer location and ethnicity (mean ΔAUC, 0.02), but varied substantially across 25 sites (28% with AUC<0.80; 32% with AUC ≥0.90) and by image quality (AUC, 0.78-0.88). Conclusion AI demonstrated diagnostic performance comparable to that of radiology readings across external diagnostic and screening datasets. © The Author(s) 2026. Published by the Radiological Society of North America under a CC BY 4.0 license.

Background The prevalence of incomplete disproportionately enlarged subarachnoid space hydrocephalus (DESH) and its cognitive relevance remain unclear. Purpose To determine the prevalence of complete and incomplete DESH and their associations with baseline cognitive impairment and follow-up cognitive decline. Materials and Methods This prospective community-based cohort (age ≥ 65 years) included participants who underwent baseline brain MRI and were followed for 5-7 years. Two radiologists assessed baseline MRI scans for core DESH features: Evans index greater than 0.3, enlargement of the Sylvian fissures (ESF), and tightness of the high-convexity sulci (THC). Complete DESH was defined as all three core features, incomplete DESH as one or two core features, and no DESH as zero core features. Feature combinations were modeled as single binary indicators of copresence (eg, THC plus ESF was 1 if both were present and 0 otherwise). Separate cross-sectional and longitudinal logistic regression models were used to evaluate associations of baseline imaging features with concurrent cognitive impairment and follow-up cognitive decline, respectively. Longitudinal models were fitted separately in participants with normal cognition and in a combined cohort of participants with normal cognition or mild cognitive impairment at baseline. Results Among 2133 participants (median age, 69 years [IQR, 67-73 years]; 1304 female participants), complete DESH, incomplete DESH, and no DESH were present in 37 (1.7%), 988 (46.3%), and 1108 (51.9%), respectively. There was no evidence of an association between baseline imaging features and baseline cognitive impairment (all Holm-adjusted P > .05). Baseline THC was associated with follow-up cognitive decline in the cognitively normal cohort (odds ratio [OR], 2.95 [95% CI: 1.95, 4.45]; Holm-adjusted P < .001) and in the combined cohort (OR, 2.87 [95% CI: 1.96, 4.21]; Holm-adjusted P < .001). THC plus ESF was associated with decline only in the combined cohort (OR, 1.83 [95% CI: 1.16, 2.87]; Holm-adjusted P = .04). Conclusion Incomplete DESH was more prevalent than complete DESH. Baseline THC was associated with subsequent cognitive decline. © RSNA, 2026 Supplemental material is available for this article. See also the editorial by Haller in this issue.

Purpose To evaluate the prevalence, upgrade rate, and radiologic surveillance management of high-risk lesions (HRLs) detected at screening mammography in a Dutch breast cancer screening population. Materials and Methods This retrospective analysis of a prospectively maintained database included patients recalled from the Dutch breast cancer screening program between January 2009 and July 2019. Incidence rates, diagnostic work-up, radiologic surveillance, and upgrades to (pre)malignancy after surgical excision and during radiologic surveillance were evaluated. Results Among 17 809 recalled patients, 514 patients with a mean age of 58 years ± 8.1 (SD) were diagnosed with an HRL. The incidence rate of HRLs was 0.83 per 1000 screens and 2.89 per 100 recalls. The majority of HRLs consisted of papillary lesions (34.4% [177 of 514]) and atypical ductal hyperplasia (ADH) (31.1% [160 of 514]). Surgical excision was performed in 233 cases (45.3%), resulting in 58 HRLs (24.9%) being upgraded to (pre)malignancy. Invasive tumors were mainly found in papillary lesions with atypia and ADH. Of patients diagnosed with an HRL, 324 (63.0%) had an indication for radiologic surveillance. Of these, 257 (79.3%) underwent surveillance, with 109 (42.4%) completing the recommended 5-year surveillance trajectory. During surveillance, 26 patients (10.1%) developed a (pre)malignancy. Invasive tumors were more frequently identified among HRLs upgraded during surveillance than among HRLs upgraded after surgical excision (17 of 26 [65%] vs 16 of 58 [28%]; P = .001). HRLs upgraded to invasive cancer were more likely to be triple-negative compared with screen-detected cancers (9.1% [3 of 33] vs 6.6% [215 of 3277]; P < .001). Conclusion Overall, 16.3% (84 of 514) of screen-detected HRLs were associated with a diagnosis of (pre)malignancy after surgical excision or during radiologic surveillance. Completion of the recommended 5-year surveillance trajectory was achieved in fewer than half of patients undergoing surveillance. Keywords: Breast Mammography, MR-Imaging, Ultrasound, Biopsy/Needle Aspiration, Screening Supplemental material is available for this article. © RSNA, 2026.

Myocardial strain imaging enables quantification of cardiac deformation. Cardiovascular magnetic resonance imaging (CMR) is well suited for strain assessment due to the ability to image in any given plane with high spatial and contrast resolution. CMR strain measures have incremental diagnostic and prognostic utility over conventional clinical imaging parameters across disease states. Routine integration of CMR strain assessment in clinical practice has been hindered by the lack of agreement on imaging protocols and analysis methods, variability due to noise sensitivity, and a paucity of robust normative age-, sex- and ethnicity-specific reference ranges. In recognition of the expanding applications of strain techniques in clinical and research CMR, this joint SCMR/RSNA/EACVI scientific statement integrates data from original research studies, guidelines, and opinions from experts across the field to guide responsible and evidence-based utilization of CMR strain. © 2026 The Author(s). Published by Elsevier Inc. on behalf of Society for Cardiovascular Magnetic Resonance, by Oxford University Press on behalf of European Society of Cardiology, and by RSNA. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by/4.0/). Supplemental material is available for this article. This paper was jointly developed by Journal of Cardiovascular Magnetic Resonance, European Heart Journal - Cardiovascular Imaging, and Radiology and jointly published by Elsevier Inc, Oxford University Press, and RSNA. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. Any citation can be used when citing this article.

There is a clinical need for high-spatial-resolution, electrocardiography (ECG)-gated, respiratory-navigated contrast-enhanced (CE) thoracic MR angiography (MRA; hereafter, NAV CE MRA) robust to physiologic motion artifacts. Compared with first-pass gated techniques, ECG-triggered NAV MRA more effectively suppresses motion and exhibits greater acquisition efficiency and/or artifact mitigation than non-CE MRA. Gradient-echo or balanced steady-state free precession NAV CE MRA has conventionally used diaphragmatic navigators to minimize respiratory motion and parallel imaging for acquisition acceleration. The development of image-based navigators (iNAVs) and variable golden-step Cartesian trajectory with spiral profile order sampling represents a progressive technologic innovation for three-dimensional thoracic CE MRA (hereafter, iNAV CE MRA). iNAV CE MRA can also be combined with time-resolved angiography and abdominopelvic first-pass CE MRA for dynamic information and/or extended anatomic coverage. In this review, we describe techniques for NAV CE MRA motion correction, contrast agent considerations, noncontrast alternatives, use in clinical applications, limitations, and future potential. Keywords: MR Angiography, Congenital, Aorta, Pulmonary Veins, Motion Correction, Aortic Disease, Congenital Heart Disease, Pulmonary Vein Angiography, Variable Density Sampling Supplemental material is available for this article. © The Author(s) 2026. Published by the Radiological Society of North America under a CC BY 4.0 license.