AJNR. American journal of neuroradiology最新文献

{"title":"Predicting Intracranial Aneurysm Rupture Risk and Intervention Outcomes Using Denoising-Enhanced CTA.","authors":"Hai Jin, Ligang Chen, Tingzhun Zhu, Guangxin Chu, Liang Ma, Guobiao Liang, Zheng Zou, Chunyong Yu","doi":"10.3174/ajnr.A9093","DOIUrl":"10.3174/ajnr.A9093","url":null,"abstract":"<p><strong>Background and purpose: </strong>Our aim was to develop a comprehensive multimodal framework for assessing the rupture risk of intracranial aneurysms and predicting intervention outcomes. In addition, it seeks to a novel denoising algorithm to enhance the quality of CTA images, thereby improving morphologic profiling.</p><p><strong>Materials and methods: </strong>This retrospective multicenter study included 352 patients with intracranial aneurysms who underwent CTA. A multimodal framework was developed, integrating 3 complementary feature sets: clinical variables, radiomic texture features, and deep learning-derived aneurysm morphologic data. A novel denoising algorithm was applied to improve image quality, thereby enhancing prediction performance. Model validation was performed through cross-validation, using multiple end points, including the Hunt-Hess, World Federation of Neurosurgical Societies (WFNS), and mRS grading systems.</p><p><strong>Results: </strong>The multimodal framework demonstrated robust performance, achieving an area under the curve (AUC) of 0.896 [0.819-0.973] for aneurysm rupture prediction, outperforming conventional single-technique models (radiomics-based model: 0.752 [0.693-0.809]; deep learning-based model: 0.823 [0.789-0.827]). Incorporating the denoising technique further enhanced performance, with the AUC for rupture prediction increasing to 0.908 [0.836-0.981]. In clinical grading tasks, the model showed strong efficacy, achieving an AUC of 0.907 [0.845-0.968] for Hunt-Hess grading, 0.883 [0.662-0.988] for World Federation of Neurosurgical Societies grading, and 0.926 [0.879-0.973] for mRS.</p><p><strong>Conclusions: </strong>Our system demonstrates promising performance in predicting aneurysm rupture and clinical grading assessments, indicating its potential for comprehensive aneurysm evaluation. Moreover, the proposed denoising method effectively mitigates noise interference, enhances morphologic edge features, and improves the accuracy of existing models.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1250-1258"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138576/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145491151","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":"Microcirculatory Collaterals Modulate Ischemic Core Heterogeneity on Diffusion-Weighted Imaging.","authors":"Aroosa Zamarud, Michael Mlynash, Nicole Yuen, Henk van Voorst, Adrien Ter Schiphorst, Pierre Seners, Anke Wouters, Maya Schwartz, Greg W Albers, Bruce Campbell, Seena Dehkharghani, Maarten G Lansberg, Jeremy J Heit","doi":"10.3174/ajnr.A9178","DOIUrl":"10.3174/ajnr.A9178","url":null,"abstract":"<p><strong>Background and purpose: </strong>Endovascular thrombectomy (EVT) is an effective treatment for acute ischemic stroke due to large vessel occlusion (AIS-LVO). The ischemic core is best determined on DWI, which is commonly thresholded for automated analysis using ADC maps. However, there may be substantial heterogeneity in ADC values within the ischemic core. We determined how tissue-level collaterals, measured by hypoperfusion intensity ratio (HIR) on cerebral perfusion imaging, influences ischemic core heterogeneity.</p><p><strong>Materials and methods: </strong>We performed a post hoc analysis of the CT Perfusion to Predict Response to Recanalization in Ischemic Stroke Project 2 (CRISP 2) study of patients with AIS-LVO who underwent baseline CT/CTP and follow-up MRI/MR perfusion (MRP) prior to EVT. Patients were dichotomized into favorable (HIR ≤0.5) and unfavorable (HIR >0.5) groups, and variability in ADC reduction was determined across an ischemic core defined by standard thresholds of ADC ≤620 × 10-6 mm²/s.</p><p><strong>Results: </strong>One hundred ninety-seven CRISP 2 patients met criteria: 113 (57%) favorable HIR and 84 (43%) unfavorable HIR. Favorable HIR patients had lower baseline NIHSS scores (median 14 versus 16; <i>P</i> = .012), smaller hypoperfusion volumes (time-to-maximum >6 seconds and >10 seconds), smaller ischemic core volumes (27 mL versus 50 mL; <i>P</i> < .001), and were less frequently treated with IV thrombolysis (29% versus 45%; <i>P</i> = .016). ADC heterogeneity was lower in favorable HIR (standard deviation: 167.2 versus 193.5; <i>P</i> = .01), but the mean ADC was similar between groups. Clinical outcomes were not different between favorable and unfavorable HIR groups. Multivariable analysis showed HIR was independently associated with ADC standard deviation (<i>P</i> = .002) and coefficient of variation (<i>P</i> = .003) at the comprehensive stroke center.</p><p><strong>Conclusions: </strong>Favorable tissue-level collaterals (low HIR) are associated with reduced ischemic core ADC heterogeneity.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1222-1227"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138556/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147824608","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":"MRI and Clinical Features of Nonenhancing <i>IDH</i>-Wild-Type Glioblastomas: How to Make an Early Diagnosis and Distinguish from Mimics.","authors":"James Ryan Loftus, Kanwar P Singh, Sohil H Patel, Matthew D Lee, Matija Snuderl, Daniel Orringer, Rajan Jain","doi":"10.3174/ajnr.A9272","DOIUrl":"https://doi.org/10.3174/ajnr.A9272","url":null,"abstract":"<p><strong>Background and purpose: </strong>A small subset of <i>isocitrate dehydrogenase</i>-wild-type (<i>IDH</i>-wt) glioblastomas (GBMs) initially present as nonenhancing, T2 FLAIR hyperintense cortical/superficial lesions on MRI, potentially leading to misdiagnosis on the initial imaging and hence delayed treatment. This study aimed to characterize the clinical and MRI features of nonenhancing <i>IDH</i>-wt GBMs to help radiologists in differentiating them from nonmalignant mimic diagnoses (eg, encephalitis). Additionally, the histologic, genomic, and survival profiles of nonenhancing GBMs were compared with those of enhancing GBMs.</p><p><strong>Materials and methods: </strong>Clinical and MRI features from 32 patients, each with nonenhancing and enhancing GBMs, and 16 patients with nonmalignant mimic differential diagnoses from a single institution and publicly available data set were retrospectively analyzed. Imaging features were reviewed using the Visually Accessible Rembrandt Images features and the split ADC sign. χ² tests and a binary logistic regression model were used to compare nonenhancing <i>IDH</i>-wt GBMs with nonmalignant mimics. Histopathologic and genomic analyses were performed on institutional cases. Overall survival between nonenhancing and enhancing GBMs was compared using Kaplan-Meier analysis.</p><p><strong>Results: </strong>No significant difference in age, clinical presentation, or duration of symptoms was found between nonenhancing GBMs and nonmalignant mimics. Imaging features favoring nonenhancing GBMs included a greater proportion of non-contrast-enhancing tumor (OR, 7.4), larger anterior-posterior tumor dimension (OR, 8.4), restricted diffusion (OR, 3.6), and eloquent brain involvement (OR, 3.0) while features favoring mimics included greater edema (OR, 0.07), infiltrative T1 FLAIR ratio (OR, 0.68), hemorrhage (OR, 0.76), satellite lesions (OR, 0.84), and the split ADC sign (OR, 0.89). The logistic regression model achieved a mean area under the receiver operator characteristic curve of 0.89 (SD, 0.20) (accuracy 0.84, sensitivity 0.91, specificity 0.70, and precision 0.88). Twelve of 18 nonenhancing GBMs lacked histologic evidence of necrosis or microvascular proliferation (\"molecular GBMs\"). Genomic profiles were similar between nonenhancing and enhancing GBMs. Median overall survival was nonsignificantly longer in nonenhancing GBMs compared with enhancing GBMs (39 versus 21 months, <i>P</i> = .078).</p><p><strong>Conclusions: </strong>Nonenhancing GBMs demonstrate distinct MRI features that must be recognized for early diagnosis and differentiation from nonmalignant mimics. Nonenhancing GBMs demonstrated longer overall survival compared with enhancing GBMs, though they were not statistically significant.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":"47 5","pages":"1289-1295"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138569/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147847073","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":"Prevalence and Radiologic Manifestations of Internal Jugular Venous Stenosis in Patients with Pulsatile Tinnitus: A Case-Control Study.","authors":"Zhongyuan Zhang, Piers Klein, Bindu Setty, Pamela Semaan, Benjamin Soares, Thanh N Nguyen, Harprit Bedi, Osamu Sakai, Mohamad Abdalkader","doi":"10.3174/ajnr.A9092","DOIUrl":"10.3174/ajnr.A9092","url":null,"abstract":"<p><strong>Background and purpose: </strong>The role of internal jugular venous stenosis (IJVS) in the development of pulsatile tinnitus (PT) is unclear. In this study, we aim to assess the prevalence of IJVS and to analyze the associated imaging findings in patients with and without PT.</p><p><strong>Materials and methods: </strong>We conducted a case-control study of consecutive adult patients with PT who underwent imaging evaluation with CTA/CTV with contrast between February 2018 and March 2022. Age- and sex-matched controls who received CTA and/or CTV for an indication other than PT, headache, or visual disturbance were included. We compared the clinical and imaging findings between the PT and control groups. The prevalence and severity of IJVS were also analyzed.</p><p><strong>Results: </strong>A total of 148 patients with PT and 98 control patients were included. There was no difference in the prevalence of IJVS between groups (<i>P</i> = .19). No difference in stenosis grade was observed between patients with PT and those in the control group with IJVS (<i>P</i> = .61). Empty sella turcica, optic nerve tortuosity, optic nerve sheath prominence, transverse sinus stenosis (TSS), and sigmoid sinus wall abnormalities (SSWA) were greater in the PT group than in controls (all, <i>P</i> < .01). Among patients with PT, imaging findings of idiopathic intracranial hypertension (IIH) were not associated with IJVS. Among patients with IJVS, TSS and empty sella turcica were more common in patients with PT than in controls.</p><p><strong>Conclusions: </strong>IJVS was common in patients with PT and controls, with similar prevalence and severity observed in both groups. TSS and SSWA were significantly more common in patients with PT compared with controls. Among patients with PT, there was no association between imaging findings of IIH and IJVS. Other causes of PT should be sought before considering intervention for IJVS.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1320-1324"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138567/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145491186","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":"Hippocampal Subfield Susceptibility Alterations in Mild Cognitive Impairment Revealed by 7T MRI.","authors":"Gaoxing Zheng, Fang Frank Yu, Yujia Huang, Snehal Mazumder, Sophia L Vargas, Paul G Unschuld, Sonja M Kagerer, Xu Li, Jiaen Liu","doi":"10.3174/ajnr.A9094","DOIUrl":"10.3174/ajnr.A9094","url":null,"abstract":"<p><strong>Background and purpose: </strong>Hippocampal magnetic susceptibility alterations may serve as early neurodegenerative biomarkers of Alzheimer disease (AD), but subfield-level evidence in mild cognitive impairment (MCI) remains limited. This study uses submillimeter high-resolution quantitative susceptibility mapping (QSM) to investigate hippocampal subfield susceptibility changes in MCI.</p><p><strong>Materials and methods: </strong>Thirteen individuals with MCI and 13 cognitively normal controls (NC) underwent 7T MRI scans including MP2RAGE and multiecho gradient echo imaging (for QSM). The visibility of hippocampal strata radiatum, lacunosum, and moleculare (SRLM) was assessed using a visual rating scale. Hippocampal subfields (Cornu Ammonis 1 [CA1], CA2, CA3, dentate gyrus [DG], and subiculums) were segmented, and magnetic susceptibility values (χ) were extracted for each subfield. The susceptibility difference between the DG and other subfields was also calculated. Associations between subfield susceptibility measures and cognitive performance were then assessed.</p><p><strong>Results: </strong>Qualitative analysis revealed a distinct hyperintense curved pattern in the hippocampus on the 7T QSM image, corresponding to the SRLM. In NC, this pattern was clearly visible exhibiting consistently delineated boundaries, while it appeared blurred or absent in most subjects with MCI. The visual rating results showed that NC had significantly higher scores than subjects with MCI (Hedgesg = 1.43, 95% confidence interval) [95% CI, 0.60-2.35; <i>P</i> = .003], with most NC rating 3-4 and most subjects with MCI rating 1-2. Quantitative analysis of hippocampal subfield susceptibility revealed significantly elevated susceptibility [χ] in the left DG in those with MCI compared with NC (Hedgeg = 0.88, 95% CI, 0.10-1.72; <i>P</i> = .03), leading to reduced susceptibility contrast between the SRLM and adjacent CA1-CA3 or DG. Furthermore, regional differences of susceptibility between key subfields (left CA1 versus DG and subiculum versus DG) were significantly reduced in MCI, reflecting a loss of subfield contrast. These quantitative changes were significantly associated with lower cognitive performance, even when controlling for age.</p><p><strong>Conclusions: </strong>7T QSM reveals susceptibility changes in hippocampal substructures in individuals with MCI, providing a potential early biomarker for AD.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1308-1314"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12797140/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145491108","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":"ACR-ASNR-SNIS-SPR Practice Parameter for the Performance of Magnetic Resonance Angiography (MRA) of the Head and Neck.","authors":"Reade Andrew De Leacy, Colin Segovis, Aparna Singhal, Patrick A Brown, Adam E Goldman-Yassen, Doris D M Lin, Gaurav Saigal, Guilherme Dabus, Jeremy J Heit, Steven W Hetts, Kartik Reddy, Maura E Ryan, John Amodio, Lubdha M Shah","doi":"10.3174/ajnr.A9108","DOIUrl":"10.3174/ajnr.A9108","url":null,"abstract":"<p><strong>Aim/objectives/background: </strong>This practice parameter was revised collaboratively by the American College of Radiology (ACR), the American Society of Neuroradiology (ASNR), the Society of NeuroInterventional Surgery (SNIS), and the Society for Pediatric Radiology (SPR).<i>This practice parameter provides a consensus-based guide for the safe, effective performance and interpretation of MRA imaging in the head and neck for adults and children.</i> METHODS: This parameter was revised according to the process described under the heading <i>The Process for Developing ACR Practice Parameters and Technical Standards</i> on the ACR website (<u>https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards</u>) by the Committee on Practice Parameters - Neuroradiology of the ACR Commission on Neuroradiology, the Committee on Practice Parameters - Interventional and Cardiovascular Radiology of the ACR Commission on Interventional and Cardiovascular Radiology, and the Committee on Practice Parameters - Pediatric Radiology of the ACR Commission on Pediatric Radiology in collaboration with the ASNR, the SNIS, and the SPR.</p><p><strong>Results: </strong>The document outlines practice parameters for performing MRA in the head and neck in both adults and children. It reviews the clinical indications for imaging and elaborates on the major imaging techniques with advice for imaging optimization, equipment requirements, reporting standards and potential pediatric adaptations emphasizing consistent practice, patient safety, and the role of evolving technology in neurovascular diagnosis. It is intended to form an educational framework rather than reflect rigid standard of care.</p><p><strong>Conclusions: </strong>This practice parameter promotes standardized, safe, and clinically effective use of head and neck MRA, ensuring high-quality cerebrovascular imaging while allowing flexibility for evolving technology and individual patient needs.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1161-1173"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138565/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147522818","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":"Emergent Carotid Angioplasty or Stenting for Internal Carotid-Middle Cerebral Artery Tandem Occlusion Strokes: Real-World Outcomes in a Nationwide Cohort.","authors":"Huanwen Chen, Matthew K McIntyre, Dhairya A Lakhani, Ajay Malhotra, Marco Colasurdo, Dheeraj Gandhi","doi":"10.3174/ajnr.A9169","DOIUrl":"10.3174/ajnr.A9169","url":null,"abstract":"<p><strong>Background and purpose: </strong>While endovascular thrombectomy (EVT) of intracranial occlusions is currently guideline-recommended, whether additional emergent balloon angioplasty (BA) or carotid artery stent placement (CAS) is effective and safe for patients with internal carotid-middle cerebral artery tandem occlusion (TO) is less clear. This study evaluated the outcomes following EVT combined with BA versus CAS alone for patients with TO.</p><p><strong>Materials and methods: </strong>This was a retrospective cohort study of the Nationwide Readmissions database (2016-2022). Patients with ipsilateral ICA-MCA TO treated with EVT were identified, and stratified into 3 groups: EVT alone, EVT + BA, and EVT + CAS. The primary end point was the patient's functional status at the time of hospital discharge as an ordinal variable, ranging from functional independence to death. Secondary outcomes included in-hospital mortality and intracranial hemorrhage (ICH). Multivariable regression analyses adjusting for patient demographics, stroke severity, and comorbidities were used to account for confounding bias.</p><p><strong>Results: </strong>A total of 4928 patients were identified, of whom 3371 (68.4%) received EVT alone; 541 (11.0%), EVT + BA; and 1015 (20.6%), EVT + CAS. Compared with EVT alone, EVT + BA was not associated with significant differences in functional outcomes, mortality, or ICH (all adjusted <i>P</i> value > .05), whereas EVT + CAS was associated with improved functional status (adjusted common OR, 1.27 [95% CI, 1.04-1.55], <i>P</i> = .02) and mortality (11.2% versus 21.6%; adjusted OR, 0.62 [95% CI, 0.47-0.82], <i>P</i> < .001), without significantly increased ICH (37.5% versus 34.4%; adjusted OR, 1.27 [95% CI, 0.99-1.64], <i>P</i> = .06).</p><p><strong>Conclusions: </strong>Emergent EVT + CAS for patients with TO was associated with improved functional outcomes and reduced in-hospital mortality without significantly increasing the ICH risk.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1244-1249"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138571/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147824584","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":"T2 Hyperintensity and ADC Values in Fetal Brain MRI following Prenatal Open Neural Tube Defect Repair.","authors":"Romain Corroenne, Magdalena Sanz Cortes, William E Whitehead, Livja Mertiri, Michael A Belfort, Thierry A G M Huisman","doi":"10.3174/ajnr.A9099","DOIUrl":"https://doi.org/10.3174/ajnr.A9099","url":null,"abstract":"<p><strong>Background and purpose: </strong>T2 hyperintensity on fetal brain MRI is frequently observed in fetuses with an open neural tube defect (ONTD) and may reflect edema, impaired CSF circulation, or altered brain maturation. By characterizing the diffusion of water molecules within brain tissue, DWI may help differentiate among these etiologies by assessing water diffusion as a marker of brain microstructure. Our aim was to investigate the relationship between brain T2-hyperintensity and ADC values in fetuses following prenatal ONTD repair.</p><p><strong>Materials and methods: </strong>We retrospectively analyzed fetal MRI scans performed 6 weeks after in utero ONTD repair at a single center. T2 hyperintensity was defined as a region with signal intensity subjectively higher than that of the surrounding brain parenchyma. ADC values were measured in the frontal, temporal, parietal, and occipital lobes on axial brain DWI sequences (<i>b</i>=700 s/mm²). Hindbrain herniation was evaluated, and reversal was defined when the cerebellum was seen above the foramen magnum. ADC values were compared between fetuses with and without T2 hyperintensity using the Mann-Whitney <i>U</i> test. A <i>P</i> value < .05 was considered significant.</p><p><strong>Results: </strong>Forty-nine fetuses underwent repair at 25.0 [23.3-26.4] weeks. During the postoperative MRI at 31.2 [29.9-33.3] weeks, T2 hyperintensity was seen in 35/49 (71.4%) fetuses. ADC values were lower in most studied brain regions in fetuses with T2 hyperintensity compared with their counterparts without T2 hyperintensity (right parietal lobe: 2.68 [1.38-7.82] ×10^{-6 mm2/s} versus 3.36 [2.32-7.05] ×10^{-6 mm2/s}, <i>P</i> = .02; left parietal lobe: 2.80 [1.40-7.38] versus 3.45 [1.81-7.58] ×10^{-6 mm2/s}, <i>P</i> = .03; right temporal lobe: 2.75 [1.41-6.63] versus 3.53 [1.87-7.58] ×10^{-6 mm2/s}, <i>P</i> <.01; right occipital lobe: 3.19 [1.20-7.86] versus 4.30 [2.18-7.18], <i>P</i> = .04). Complete hindbrain herniation reversal was more common in those without T2 hyperintensity (100% versus 65.7%, <i>P</i> < .01).</p><p><strong>Conclusions: </strong>After prenatal ONTD repair, the presence of T2 hyperintensity was associated with lower ADC values in most examined brain regions, suggesting altered brain microstructure or delayed myelination.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":"47 5","pages":"1380-1385"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138552/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147847051","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":"Correlation of MRI Markers with Clinical Features in Multiple System Atrophy.","authors":"Nan Jin, Jiaxiang Li, Xinhui Chen, Yixin Kang, Haotian Wang, Xinchen Wang, Xiaosheng Zheng, Zhiru Lin, Bo Wang, Wei Luo","doi":"10.3174/ajnr.A9078","DOIUrl":"10.3174/ajnr.A9078","url":null,"abstract":"<p><strong>Background and purpose: </strong>MSA is a progressive neurodegenerative disorder with two main subtypes: MSA with predominant cerebellar ataxia (MSA-C) and MSA with predominant parkinsonism (MSA-P). The latest diagnostic criteria emphasize the importance of neuroimaging markers from MRI alongside clinical symptomatology assessment. This study investigates the relationship between visual MRI markers and multiple system atrophy (MSA) subtypes, clinical features, and cerebral glucose metabolism and striatal dopaminergic degeneration.</p><p><strong>Materials and methods: </strong>Eighty-nine patients with MSA, 67 with predominant parkinsonism (MSA-P) and 22 with predominant cerebellar ataxia (MSA-C), underwent extensive clinical and neuropsychiatric evaluations and routine MRI scans to assess markers like the hot-cross bun (HCB) sign, putaminal iron deposition, midbrain to pons (M/P) ratio, and cerebellar atrophy. PET imaging with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) and ¹¹C-2β-carbomethoxy-3β-(4-fluorophenyl) tropane (¹¹C-CFT) was performed to evaluate brain metabolism and striatal dopaminergic uptake abnormalities.</p><p><strong>Results: </strong>Canonical correlation analysis revealed significant associations between clinical symptoms and MRI markers, particularly the HCB sign, M/P ratio, and putaminal iron deposition. The HCB sign and M/P ratio correlated with cerebellar dysfunction, while putaminal iron deposition correlated with parkinsonism severity, particularly in MSA-P. Cerebellar and putaminal metabolism negatively correlated with their respective structural changes. However, putaminal iron deposition showed no significant correlation with striatal dopaminergic uptake.</p><p><strong>Conclusions: </strong>Visual MRI markers are crucial for diagnosing MSA and delineating disease subtype and symptom severity. Supratentorial and infratentorial MRI markers reflect the severity of parkinsonism and cerebellar dysfunction, respectively. Putaminal iron deposition reflects the severity of parkinsonism, suggesting that iron deposition plays an important role in the pathophysiological mechanisms contributing to parkinsonism in MSA.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1296-1305"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138562/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145460954","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":"Optimizing 3D Cerebral Angiographic Imaging Techniques for Gamma Knife Radiosurgery: Technical Considerations for Arteriovenous Shunt Treatment.","authors":"Ryuichi Noda, Mariko Kawashima, Yuki Kamiya, Tomohiro Inoue, Atsuya Akabane","doi":"10.3174/ajnr.A9196","DOIUrl":"10.3174/ajnr.A9196","url":null,"abstract":"<p><p>3D cerebral angiographic imaging offers superior spatial resolution and flexible acquisition compared with CTA, enabling selective injections and dynamic phase selection.^1-4 Its application in gamma knife radiosurgery has been increasingly recognized, particularly for arteriovenous shunts, where precise visualization of angioarchitecture is essential.^5-12 We describe strategies for incorporating 3D rotational angiography and conebeam CT into treatment planning, highlighting their respective strengths and limitations.^7,8,12-16 Imaging can be performed either before or after frame fixation, each approach carrying unique advantages and constraints.^19,20 Postprocessing-targeted reconstruction, MIP/MPR, subtraction imaging, and metal-artifact reduction-further refines visualization, highlighting the complementary value of each technique.^17,18 These tools enhance confidence in nidus delineation and planning accuracy. Collaboration with endovascular specialists is critical for optimal acquisition and data sharing. This video presents technical considerations and practical tips to optimize the clinical use of 3D angiographic imaging in gamma knife radiosurgery for arteriovenous shunt management.</p>","PeriodicalId":93863,"journal":{"name":"AJNR. American journal of neuroradiology","volume":" ","pages":"1228-1229"},"PeriodicalIF":0.0,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147791803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}