Frontiers in radiology最新文献

{"title":"Harmonization of slice thickness through resampling improves comparability of MRI-derived neonatal brain volumes.","authors":"Anouk S Verschuur, Martijn F Boomsma, Alexander Leemans, Ingrid M Nijholt, Leonora Hendson, Selma Low, Amy Metcalfe, Donna M Slater, Chantal M W Tax, Gerda Meijler, Lara M Leijser","doi":"10.3389/fradi.2026.1868602","DOIUrl":"10.3389/fradi.2026.1868602","url":null,"abstract":"<p><strong>Purpose: </strong>To assess reliability and agreement of brain volume measurements from neonatal T2-weighted magnetic resonance imaging (MRI) scans acquired with different slice thickness settings (i.e., 2 mm, 3 mm and 3 mm resampled).</p><p><strong>Methods: </strong>We used term-equivalent (38-45 weeks postmenstrual age) T2-weighted MRI scans with slice thicknesses of 2 mm and 3 mm from a subset of 40 preterm and term infants (27-40 weeks' gestation) from two existing neonatal imaging cohorts. Resampling of the 2 mm scans to a 3 mm grid provided a third set of scans, referred to as \"3 mm resampled\". Automated brain segmentation provided intracranial volume, total brain volume, and volumes for eight brain structures. Reliability and agreement of volume measurements were assessed using intraclass correlation coefficients (ICC) and Bland-Altman plots, respectively.</p><p><strong>Results: </strong>For all volumes, inter-scan reliability was higher for 3 mm vs. 3 mm resampled scans (mean observer ICC >0.92) compared to 2 mm vs. 3 mm scans (mean observer ICC >0.87). Bland-Altman plots revealed smaller mean volume differences between 3 mm and 3 mm resampled scans than between 2 mm and 3 mm scans. However, a proportional bias was found for deep gray matter volume for 3 mm vs. 3 mm resampled scans.</p><p><strong>Conclusion: </strong>Slice thickness influences brain volume measurements from neonatal MRI. Harmonization of imaging data acquired with different settings through image resampling improves reliability and agreement of brain volume measurements.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1868602"},"PeriodicalIF":4.0,"publicationDate":"2026-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13357915/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148439246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-phase CT radiomics for acute kidney injury prediction after out-of-hospital cardiac arrest.","authors":"Michael Scheschenja, Lisa Hekers, Julian Kreutz, Birgit Markus, Susanne Betz, Jarmila Jedelská, Alexander König, Andreas H Mahnken, Simon Viniol","doi":"10.3389/fradi.2026.1875412","DOIUrl":"10.3389/fradi.2026.1875412","url":null,"abstract":"<p><strong>Background: </strong>Acute kidney injury (AKI) is common and prognostically relevant after out-of-hospital cardiac arrest (OHCA), yet early risk prediction at admission remains limited.</p><p><strong>Objective: </strong>To assess whether radiomics features from dual-phase contrast-enhanced CT obtained at admission predict AKI after non-traumatic OHCA.</p><p><strong>Methods: </strong>This retrospective single-center study included consecutive non-traumatic OHCA patients with return of spontaneous circulation undergoing standardized admission dual-phase CT. AKI within 5 days was defined by KDIGO criteria or renal replacement therapy. Bilateral whole-kidney masks were generated using TotalSegmentator, reviewed, and corrected if necessary. Radiomics features were extracted with PyRadiomics within 3DSlicer. Features with poor reproducibility (CCC < 0.75) were excluded. Arterial-venous difference features were computed. Data were split into a training cohort and test cohort. Feature selection used mRMR followed by LASSO regression, yielding seven predictors for training of a logistic regression (LR) model, a support vector machine (SVM), and a k-nearest neighbors (kNN) model. Additionally, a limited clinical variable LR model and a combined model were evaluated. Stability was assessed by <i>post hoc</i> repeated resampling of the primary radiomics LR model across 100 stratified 70/30 splits, summarizing repetitions yielding 3-9 LASSO-selected features.</p><p><strong>Results: </strong>Of 383 screened patients, 155 were included, of which 47 (30.3%) developed AKI. In the test cohort, radiomics-LR showed the highest AUC (0.783), with kNN (0.778) and SVM (0.757) performing comparable. The limited clinical model performed poorly (AUC 0.549), and the combined model (AUC 0.779) did not materially improve upon radiomics alone. In the repeated resampling analysis, 29 of 100 repetitions fulfilled the predefined feature-count criterion. Among these repetitions, median test-set AUC was 0.663 (IQR, 0.623-0.699), indicating moderate but variable discriminatory performance and limited feature-selection stability. Most selected predictors were arterial-venous difference features.</p><p><strong>Conclusions: </strong>This exploratory single-center proof-of-concept study suggests that admission dual-phase CT radiomics may contain information relevant to early AKI risk stratification after OHCA, with arterial-venous difference features appearing particularly informative. However, limited stability of feature selection and model performance indicates that these findings should be considered hypothesis-generating and require methodological refinement, comparison with more comprehensive clinical models, and external validation in prospective multicenter cohorts before clinical application can be considered.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1875412"},"PeriodicalIF":4.0,"publicationDate":"2026-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13350171/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148427094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Access to care, treatment pathways, and outcomes of endovascular treatment for aneurysmal subarachnoid hemorrhage in Kazakhstan: a retrospective cohort study.","authors":"Mynzhylky Berdikhojayev, Aiman Maidan, Karlygash Toguzbaeva, Dimash Davletov, Abzal Zhumabekov, Shayakhmet Makhanbetkhan, Daulet Suieumbetov, Rauan Aiteli, Maxat Mussabekov, Roger Barranco Pons, Marat Sarshayev","doi":"10.3389/fradi.2026.1845453","DOIUrl":"10.3389/fradi.2026.1845453","url":null,"abstract":"<p><strong>Background: </strong>Aneurysmal subarachnoid hemorrhage (aSAH) remains a major cause of mortality and disability worldwide. Outcomes after aSAH are influenced not only by hemorrhage severity and aneurysm characteristics but also by patient comorbidities, healthcare organization, and access to specialized neurovascular care. This study evaluated clinical and health-system determinants of functional outcome after aSAH in Kazakhstan.</p><p><strong>Methods: </strong>We conducted a single-center retrospective cohort study of 483 patients with ruptured intracranial aneurysms treated endovascularly at a national tertiary neurovascular center (2016-2024). Early aneurysm occlusion was defined as treatment within 24 h of symptom onset. For cohort analyses, patients treated within 14 days were classified as the acute group, whereas those treated after 14 days comprised the delayed-treatment group, including both referral-related delays and deferred treatment after clinical stabilization. Demographic, clinical, radiological, and procedural variables were analyzed. Functional outcomes were assessed using the modified Rankin Scale (mRS) at discharge, 6 months, and 12 months. Favorable recovery was defined as mRS ≤2 at 6-12 months.</p><p><strong>Results: </strong>The mean age was 52.6 years, and 65.4% were female. Rural residence was associated with delayed access to treatment (60.9% vs. 42.9%, <i>p</i> < 0.001). In the representative 2021 referral cohort, the median interval from SAH onset to arrival at the tertiary neurovascular center was 26 days (IQR 9-54), reflecting substantial referral and transfer delays within the centralized healthcare system. In multivariable analysis, periprocedural complications (adjusted OR 8.68, <i>p</i> < 0.001) and ischemic heart disease (adjusted OR 3.07, <i>p</i> = 0.012) were independently associated with mRS 3-6, whereas higher admission Glasgow Coma Scale scores were protective (adjusted OR 0.64, <i>p</i> < 0.001). Aneurysm morphology and traditional SAH severity scales were not independently associated with long-term outcome.</p><p><strong>Conclusions: </strong>Functional outcome after aneurysmal SAH within a centralized upper-middle-income neurovascular system was driven primarily by neurological status, systemic comorbidity, and procedural safety rather than aneurysm anatomy. Given the treatment-based referral design and survivorship bias inherent in tertiary transfer cohorts, these findings suggest that centralized systems facilitate access to specialized neurovascular care for patients reaching tertiary centers. Strengthening complication prevention, cardiovascular risk reduction, and referral pathways may improve neurovascular outcomes.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1845453"},"PeriodicalIF":4.0,"publicationDate":"2026-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13350253/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148426999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transcatheter arterial embolization using n-butyl cyanoacrylate metacryloxysulfolane for traumatic or iatrogenic non-visceral hemorrhage.","authors":"Paolo Federico Garducci, Bernardo Proner, Timo Alexander Auer, Florian Nima Fleckenstein, Francesco Giurazza, Pietro Roccatagliata, Claudio Carruba, Romaric Loffroy, Federico Collettini","doi":"10.3389/fradi.2026.1878048","DOIUrl":"10.3389/fradi.2026.1878048","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the safety and effectiveness of transcatheter arterial embolization (TAE) using n-butyl cyanoacrylate metacryloxysulfolane (NBCA-MS) as a first-line embolic agent for the management of traumatic and iatrogenic non-visceral arterial hemorrhages in an emergency setting.</p><p><strong>Materials and methods: </strong>This retrospective study included all consecutive patients who underwent selective TAE with NBCA-MS for non-visceral hemorrhage of traumatic or iatrogenic origin between June 2021 and June 2025. All patients were assessed with contrast-enhanced multidetector computed tomography (CT) demonstrating active arterial bleeding or pseudoaneurysm prior to embolization. TAE was performed via a femoral approach using selective microcatheterization, followed by embolization with NBCA-MS mixed with ethiodized oil at variable dilutions. Technical success was defined as complete angiographic occlusion of the bleeding vessels. Clinical success was defined as sustained hemostasis without need for repeat endovascular or surgical intervention /within 30 days. Procedure-related complications were recorded according to CIRSE guidelines.</p><p><strong>Results: </strong>Fifty-four patients (37 males; median age 60.5 years) underwent 54 TAE procedures. Traumatic hemorrhage accounted for 83.3% of cases, and iatrogenic hemorrhage for 16.7%. A single artery was embolized in 72.2% of procedures. Technical success was achieved in all cases (100%). Clinical success was observed in 46 patients (85.2%). Six patients required repeat embolization due to hemorrhage from vessels within the same vascular territory that had not been bleeding during the initial procedure and were therefore not embolized at that time. No procedure-related deaths, major complications, or off-target embolizations were observed.</p><p><strong>Conclusion: </strong>NBCA-MS-based TAE is a safe, effective, and versatile treatment for traumatic and iatrogenic non-visceral arterial hemorrhage. Its high technical success, favorable clinical outcomes, and excellent safety profile support its use as a reliable first-line embolic agent in urgent clinical scenarios.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1878048"},"PeriodicalIF":4.0,"publicationDate":"2026-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13348071/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148426354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advanced MRI for targeting the pallidothalamic region in magnetic resonance-guided focused ultrasound: the mammillothalamic tract as an adjacent imaging landmark.","authors":"Francisco Rivera, Nelson Quintanal Cordero, Fabián Piedimonte","doi":"10.3389/fradi.2026.1856951","DOIUrl":"10.3389/fradi.2026.1856951","url":null,"abstract":"<p><p>Magnetic resonance-guided focused ultrasound (MRgFUS) has expanded the therapeutic landscape for movement disorders, with growing interest in circuit-based targets such as pallidothalamic tractotomy (PTT) for Parkinson's disease. Structural MRI provides indirect orientation through surrounding landmarks, including the subthalamic nucleus, red nucleus, and internal capsule, while advanced sequences such as FGATIR and susceptibility-based imaging improve delineation of deep gray matter structures but remain limited for direct fiber visualization. Diffusion-based imaging offers complementary information by enabling <i>in vivo</i> reconstruction of white matter pathways, although tractography of pallidothalamic fibers remains constrained by crossing fiber architecture and spatial resolution. Within this context, the mammillothalamic tract represents a consistent and reproducible adjacent structure with reliable visibility on both structural and diffusion imaging. Its stable anatomical relationship to the pallidothalamic region supports its use as a practical landmark to refine stereotactic orientation when direct target visualization is not feasible. Together, these observations support a multimodal imaging framework that integrates structural and diffusion techniques to improve targeting accuracy in MRgFUS PTT. In this mini review, we aimed to synthesize the relevant anatomy of the pallidothalamic pathways and critically evaluate current MRI techniques for their localization. Additionally we sought to describe the role of identifying the mamillothalamic tract in MRgFUS-PTT planning.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1856951"},"PeriodicalIF":4.0,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13342162/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148413814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of germline BRCA mutation using clinicopathologic, MRI semantic, and radiomics features in high-risk breast cancer patients: a multicenter study.","authors":"Yoon Sang Cho, Eunje Oh, Yoo Jin Han, Kyu Ran Cho, Kyong Hwa Park, Sung Eun Song","doi":"10.3389/fradi.2026.1858292","DOIUrl":"10.3389/fradi.2026.1858292","url":null,"abstract":"<p><strong>Background and purpose: </strong>BRCA mutations are strongly associated with hereditary breast cancer and have important implications for personalized treatment; however, genetic testing may be costly. This highlights the need for noninvasive, practical approaches to prioritize patients most likely to benefit from confirmatory testing. This study evaluated the predictive value of clinicopathologic features, radiologist-assessed magnetic resonance imaging (MRI) semantic features, MRI-derived radiomics features, and their multimodal integration for identifying germline BRCA mutation status.</p><p><strong>Patients and methods: </strong>This retrospective multicenter study included high-risk breast cancer patients from two institutions (Center A and Center B) who underwent preoperative breast MRI and germline BRCA testing. Three types of predictors were used: clinicopathologic features, radiologist-assessed MRI semantic features, and MRI-derived radiomic features. Radiomics features were extracted from tumor masks on 2-minute contrast-enhanced subtraction images and T2-weighted images of preoperative MRI using a standardized, open-source PyRadiomics pipeline. Six machine learning models, including logistic regression (LR), random forest (RF), support vector machine (SVM), gradient-boosted models (LightGBM and XGBoost), and multilayer perceptron (MLP), were performed using unimodal models and their multimodal combinations. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) in both internal validation (10 repeated random train-test splits in Center A) and external cross-center validation (training on Center A and testing on Center B).</p><p><strong>Results: </strong>A total of 492 patients were included (Center A, <i>n</i> = 270; Center B, <i>n</i> = 222). In internal validation, clinicopathologic-based LR model (AUC = 0.73) and radiomics (sub-T1WI)-based gradient-boosting models (LightGBM and XGBoost) achieved the highest performance (AUC = 0.71 and 0.72, respectively). In external validation, the clinicopathologic-based RF model (AUC = 0.73) and the combined clinicopathologic and radiologist-assessed MRI-based RF model (AUC = 0.77) achieved the highest performance. The multimodal features integrating clinicopathologic, radiologist-assessed MRI, and sub-T1WI radiomics features-based LR model (AUC = 0.72) achieved comparable performance.</p><p><strong>Conclusions: </strong>A non-invasive machine learning model integrating clinicopathologic, radiologist-assessed MRI features, and radiomic signatures provides complementary predictive information for germline BRCA mutation status in high-risk breast cancer patients.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1858292"},"PeriodicalIF":4.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13328488/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148392678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The efficacy of multisite MRI scanners for total brain volume measurements: a cross-sectional study in Saudi Arabia.","authors":"Magbool Alelyani, Moawia Gameraddin, Ahmad Joman Alghamdi, Sultan Alamri, Nahla Faizo, Sahal Alotaibi, Mona Alghamdi, Samirah Althomali, Nawaf Khabrani","doi":"10.3389/fradi.2026.1818230","DOIUrl":"10.3389/fradi.2026.1818230","url":null,"abstract":"<p><strong>Background: </strong>Accurate estimation of brain structure and volume is essential in multi-scanner MRI studies investigating neurological condition. This study examines the effect of cross-scanner differences, incorporating field strength, vendor, and sequence variations, on brain volumetric measurements in Saudi adults.</p><p><strong>Objective: </strong>to evaluate the agreement, reliability and the magnitude and direction of the systematic bias of volumetric measurements between two MRI systems (1.5 T and 3 T) differing in field strength, vendor, and sequence using a within-subject same-day design.</p><p><strong>Material and methods: </strong>38 healthy participants (25.8 ± 5.6 years; 52.6% men) were scanned back-to-back on 1.5 T GE OPTIMA 450W (SPGR) at 3 T Siemens Skyra (MPRAGE). The images were analyzed using FreeSurfer v7.1.1 (longitudinal stream). To evaluate mean-level bias, a series of paired t-tests, percent differences, and false-discovery-rate (FDR) - adjusted <i>p</i>-values were computed. To evaluate order rank reliability, we used Pearson correlations, and two-way mixed-effects intraclass correlation coefficients [ICC(3,1)].</p><p><strong>Results: </strong>The global volume measurements were nearly the same on both scanners (total brain: 1 185 ± 99 mL at 1.5 T vs.1 179 ± 103 mL at 3 T; -0.6% mean difference, d = 0.07; FDR-<i>p</i> = 0.93) with excellent reliability (ICC = 0.993). The volumes of cortical GM, total GM, supratentorial, and cerebral WM showed a bias < 1.8% with excellent ICCs ≥ 0.978. On the contrary, some subcortical structures had a strong effect of cross-scanner differences after FDR correction: putamen (+13.1%, d = 1.26), amygdala (+10.1%, d = 0.95), accumbens (+36.1, d = 1.58), and thalamus (-6.6%, d = 0.70). Nevertheless, reliability of these nuclei remained good to excellent (ICC = 0.82-0.95). Some of the corpus-callosum subregions showed mixed directional changes (central: -22.0%; anterior: +8.6%) but had good reliability (ICC = 0.76-0.93).</p><p><strong>Conclusion: </strong>There is high reliability and agreement for whole-brain, cortical, and most subcortical measures between the two MRI scanners under controlled acquisition and standardized processing conditions. Systematic, region-specific biases, especially in the putamen, amygdala, accumbens, and thalamus, necessitate harmonization prior to pooling multisite data.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1818230"},"PeriodicalIF":4.0,"publicationDate":"2026-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13320661/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148371316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep learning image reconstruction technique for improving image quality and radiation dose reduction compared to iterative reconstruction technique in non-contrast CT head imaging.","authors":"Obhuli Chandran M, Saikiran Pendem, Rajagopal Kadavigere, Priyanka, Priya Ps, Cijo Chacko","doi":"10.3389/fradi.2026.1824489","DOIUrl":"10.3389/fradi.2026.1824489","url":null,"abstract":"<p><strong>Introduction: </strong>Non-contrast CT (NCCT) head is a standard imaging modality for evaluating central nervous system pathologies. Repeated CT brain examinations are associated with a cumulative risk of cancer development. Deep learning image reconstruction (DLIR) techniques help improve image quality (IQ) while reducing radiation dose (RD) compared with iterative reconstruction techniques (iDose⁴). Therefore, our study compared IQ parameters among low-dose (LD) CT with DLIR (Precise Image), LD CT with iterative reconstruction (iDose⁴), and standard-dose (SD) CT with iDose⁴ and further evaluated radiation dose reduction between SD-iDose⁴ and LD-DLIR in NCCT head imaging.</p><p><strong>Methods: </strong>Group A (SD with iDose⁴) and Group B (LD with DLIR; Precise Image) each included 96 patients. All NCCT brain scans were performed using a 128-slice incisive CT scanner (Philips Healthcare Systems) with iDose⁴ and DLIR. Qualitative and quantitative IQ analyses and radiation dose indices were compared between the groups. Lesion conspicuity was also assessed between LD-DLIR and LD-iDose⁴.</p><p><strong>Results: </strong>There was a significant reduction in RD (effective dose: 1.01 vs. 2.4 mSv; <i>p</i><0.05) with LD-DLIR. LD-DLIR demonstrated superior IQ compared with both SD-iDose⁴ and LD-iDose⁴. Subjectively, gray-white matter differentiation improved from scores of 3 (SD-iDose⁴) and 2.5 (LD-iDose⁴) to 4.5 (LD-DLIR), while overall image quality and subjective image noise increased from 3-3.5 (SD-iDose⁴) and 2.5-3 (LD-iDose⁴) to 4-4.5 with LD-DLIR (<i>p</i> < 0.05). Image noise was lowest with LD-DLIR in gray matter thalamus (GMT: 2.30-2.31) compared with SD-iDose⁴ (4.80-4.85) and LD-iDose⁴ (6.15-6.25); similar results were seen in the white matter posterior limb of the internal capsule (WMPIC: 1.98-2.21 vs. 4.36-4.38 vs. 5.19-5.32) and adjacent cortical gray matter (ACGM: 2.17-2.19 vs. 4.14-4.22 vs. 5.04-5.08). SNR was highest with LD-DLIR [GMT: 16.29-16.36 vs. 7.32-7.34 (SD-iDose⁴) and 5.61-5.75 (LD-iDose⁴); WMPIC: 14.69-14.75 vs. 6.49-6.51 vs. 5.18-5.26], and contrast-to-noise ratio (CNR) was also markedly improved [GMT-WMPIC: 2.59-2.61 (LD-DLIR) vs. 0.98-0.99 (SD-iDose⁴) and 0.82-0.83 (LD-iDose⁴); ACGM-FWM: 2.15-2.29 vs. 0.93-0.95 vs. 0.85-0.86]. Lesion conspicuity was superior with LD-DLIR for all brain lesions compared with LD-iDose⁴.</p><p><strong>Conclusion: </strong>Our study demonstrated that LD NCCT head imaging with DLIR provides superior noise reduction and improved GWMD, SNR, and CNR compared with SD and LD with iDose⁴ and supports the clinical utilization of DLIR.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1824489"},"PeriodicalIF":4.0,"publicationDate":"2026-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13314777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148364120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case Report: Structured MRI assessment of posterior thalamic infarction in a distribution compatible with posterior choroidal artery territory presenting as Déjerine-Roussy syndrome in an adolescent: differentiating arterial ischemia from venous thrombosis and thalamic neoplasm.","authors":"ZainEdeen Zyadah, Hala Issa, Rana Issa, Anees Naser","doi":"10.3389/fradi.2026.1869031","DOIUrl":"10.3389/fradi.2026.1869031","url":null,"abstract":"<p><strong>Background: </strong>Isolated thalamic lesions with post-contrast T1 hyperintensity in children may mimic arterial infarction, cerebral venous thrombosis, inflammatory disease, or neoplasm. Structured interpretation of standard magnetic resonance imaging (MRI) sequences, particularly diffusion-weighted imaging/apparent diffusion coefficient (DWI/ADC) correlation and interval follow-up, can help distinguish these entities. Posterior thalamic infarction in a distribution compatible with posterior choroidal artery territory is rare in pediatric patients.</p><p><strong>Case presentation: </strong>A previously healthy 15-year-old female developed headache and blurred vision on the day of tetanus-diphtheria (Td) vaccination, followed by progressive right hemibody numbness, impaired hand dexterity, and severe cold allodynia over 10 days. Examination localized to the left thalamus, consistent with Déjerine-Roussy syndrome. MRI on 2 June 2024, day 10 after symptom onset, showed DWI hyperintensity with subtle corresponding ADC reduction in the left posterior thalamic/pulvinar lesion, supporting early-subacute infarction. T2/fluid-attenuated inversion recovery (FLAIR) distribution was compatible with posterior choroidal artery territory involvement. Susceptibility-weighted imaging (SWI) showed no hemorrhage or venous-congestion pattern. Post-contrast MPRAGE demonstrated patchy T1 hyperintensity interpreted as probable enhancement, but true enhancement could not be definitively confirmed because corresponding pre-contrast T1-weighted images were unavailable. Etiologic workup was unrevealing, and the event was classified as cryptogenic pediatric arterial ischemic stroke (AIS). Follow-up MRI showed reduced post-contrast T1 hyperintensity and encephalomalacic evolution.</p><p><strong>Discussion: </strong>The unilateral territorial pattern, DWI/ADC abnormality, lack of hemorrhagic venous features, and follow-up maturation favored arterial infarction over venous thrombosis or neoplasm. Available post-contrast images showed no obvious filling defect of the major dural venous sinuses or principal deep venous structures, although dedicated magnetic resonance venography/computed tomography venography (MRV/CTV) was not performed. Corresponding pre-contrast T1 images were unavailable, limiting definitive enhancement assessment. The temporal association with Td vaccination is reported for pharmacovigilance; causality cannot be established from a single case.</p><p><strong>Conclusion: </strong>This case illustrates a rare adolescent posterior thalamic infarct presenting as Déjerine-Roussy syndrome and highlights the value of DWI/ADC and follow-up MRI in evaluating thalamic lesions with post-contrast T1 hyperintensity.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1869031"},"PeriodicalIF":4.0,"publicationDate":"2026-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13303791/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bringing light to the reading room.","authors":"Christine Joyce, Mohammad Adam Kassar, Alexandria Knecht, Melissa Jung, Joe Joseph, Justin McCloskey, Jarunee Intrapiromkul, Dhairya A Lakhani, Tyler McGaughey","doi":"10.3389/fradi.2026.1821486","DOIUrl":"10.3389/fradi.2026.1821486","url":null,"abstract":"<p><strong>Background: </strong>According to the American College of Radiology (ACR) Technical Standard Guidelines, there is a recommended illuminance level for reading rooms set between 25 and 75 lux. However, these guidelines are based on studies completed in 2007-2009, which predate significant advancements in display technology. No recent study has re-evaluated these lighting conditions, and more specifically, no prior studies have examined the effects of ambient lighting on the detection of intracranial hemorrhage on non-contrast brain CT.</p><p><strong>Objective: </strong>To determine if higher ambient lighting levels (> 400 lux) significantly effects the diagnostic accuracy of board-certified neuroradiologists in detecting intracranial hemorrhage on brain CT, compared with standard low-light reading room conditions (20-70 lux).</p><p><strong>Methods: </strong>Forty-two standard-of-care non-contrast head CT scans (axial acquisitions with coronal/sagittal reformats) from a tertiary-care hospital were selected by two independent neuroradiologists. These neuroradiologists established the presence or absence of intracranial hemorrhage. Four additional board-certified neuroradiologists independently interpreted all cases twice: first in a brightly lit environment (> 400 lux, measured at desktop level) and, after a > 6-month washout period to minimize recognition memory bias, in a standard reading room (20-70 lux). Interpretations were performed on calibrated Barco MDNC-3421 displays using the institutional Fuji PACS. Sensitivity, specificity, and accuracy were calculated for each condition and compared using paired two-tailed t-tests with Bonferroni correction for multiple comparisons.</p><p><strong>Results: </strong>No statistically significant differences were found between bright and dark conditions for sensitivity (0.974 vs. 0.974, <i>p</i> = 1.00), specificity (0.978 vs. 1.0, <i>p</i> = 0.49 adjusted), or overall accuracy (0.976 vs. 0.988, <i>p</i> = 1.00 adjusted).</p><p><strong>Conclusion: </strong>Increased ambient lighting levels (> 400 lux) do not significantly affect the ability of board-certified neuroradiologists to accurately detect intracranial hemorrhage on modern high-resolution displays. These findings suggest that current guidelines should be re-evaluated with recent improvements in technology. Larger multi-center studies are warranted to confirm these results across additional pathologies and modalities.</p>","PeriodicalId":73101,"journal":{"name":"Frontiers in radiology","volume":"6 ","pages":"1821486"},"PeriodicalIF":4.0,"publicationDate":"2026-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13303713/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}