Association of Glucagon-like Peptide-1 Receptor Agonist Use with Stroke and Mortality Outcomes in Asymptomatic Intracranial Atherosclerotic Disease: Propensity Score-Matched Real-World Analysis
Background: Asymptomatic intracranial atherosclerotic arterial stenosis (ICAS) is an underrecognized entity for which vascular risk-factor optimization is the primary management strategy, with no current indication for routine antiplatelet therapy or endovascular intervention for primary stroke prevention. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) reduce major adverse cardiovascular events, including stroke, in high-risk cardiometabolic populations, but their association with outcomes in asymptomatic ICAS is yet to be evaluated. The present study aims to evaluate the association between GLP-1RA use and cerebrovascular outcomes in adults with asymptomatic ICAS. Materials and Methods: We used the TriNetX US Collaborative Network (71 healthcare organizations) to identify adults (≥18 years) with ICAS between 1 January 2016 and 31 December 2025, and excluded patients with prior cerebral infarction, intracranial hemorrhage, or cerebrovascular ischemic syndromes. Exposure was defined as initiation of any GLP-1 receptor agonist (lixisenatide, semaglutide, liraglutide, tirzepatide, dulaglutide) during the 6 months before or on the date of index ICAS diagnosis. Outcomes were assessed at 1 year, and included ischemic stroke, all-cause mortality, and a composite of ischemic stroke or mortality. Propensity-score matching (1:1) was performed, including demographics, vascular risk factors, comorbidities, antithrombotics, lipid/diabetes therapies, and cardiometabolic laboratory/physiologic measures. Results: Before matching, 1746 GLP-1RA users and 71,792 non-users met inclusion criteria; after matching, 1728 patients remained in each cohort. GLP-1RA use was associated with lower 1-year risk of ischemic stroke (4.40% vs. 6.10%; hazard ratio [HR] 0.70, 95% CI 0.52–0.95; p = 0.044), lower all-cause mortality (3.40% vs. 9.40%; HR 0.35, 95% CI 0.26–0.47; p < 0.001), and lower composite outcome risk (7.50% vs. 15.00%; HR 0.48, 95% CI 0.39–0.59; p < 0.001). Notably, these associations were observed despite matching for HbA1c, LDL cholesterol, BMI, and systolic blood pressure, suggesting potential effects beyond measured cardiometabolic risk profiles. Conclusions: In this large, propensity-matched cohort of adults with a-ICAS, GLP-1RA use was associated with lower ischemic stroke, all-cause mortality, and composite outcome at 1 year. These findings are hypothesis-generating and require further prospective studies to confirm this observation.
Longitudinal MRI and Perfusion Changes in Cerebral Proliferative Angiopathy
Alcohol use disorder (AUD) is a preventable non-communicable disease that affects multiple organs and organ systems across all age groups, including the fetus and is a risk factor for developing certain cancers. Furthermore, alcohol intoxication can result in physical trauma to oneself and others, and is a contributing factor in road accidents. Early recognition of AUD is critical for improving diagnosis, management, and outcomes. Accurate diagnosis relies on comprehensive clinical evaluation and patient history. However, denial of AUD, inebriation, and lack of awareness of problems associated with AUD, can prevent early identification of the disease. AUD-associated organ damage manifests in several ways and can be recognized on imaging modalities including ultrasound, CT, and MRI. Detection of these imaging features is useful in raising suspicion of AUD or diagnosing chronic alcohol use. Radiologists should be aware of the manifestations of alcohol's effects across various organ systems and aid in the early detection and treatment of AUD. In this two-part review, the authors present a comprehensive image-based review illustrating the effects of AUD on different organ systems at various stages. This second part focuses on the imaging manifestations in the central nervous system, fetal health, cardiovascular system, and musculoskeletal system. Additionally, a brief overview of secondary imaging manifestations of alcohol use, associated with trauma and cancers, will be presented.
Nonconventional Imaging Modalities for Vestibular Schwannoma Prognosis: A Scoping Review
Objective: To explore the existing evidence on novel imaging modalities that may aid in prognostication of vestibular schwannoma (VS) clinical outcomes across various management approaches. Study design: Scoping review. Setting: Not applicable. Patients: Individuals diagnosed with VS. Interventions: Novel imaging techniques. Main outcome measures: Tumor growth and response to medical therapy. Results: A total of 18 articles were included in this review. Of these, 7 focused on pretreatment prognosis, 6 evaluated radiosurgery outcomes, 4 examined microsurgery outcomes, and 1 assessed response to bevacizumab. The imaging modalities investigated included radiomics (n = 10), positron emission tomography (PET; n = 2), dynamic contrast-enhanced MRI (DCE-MRI; n = 2), both PET and DCE-MRI (n = 1), magnetic resonance elastography (MRE; n = 1), contrast-enhanced CT (CE-CT; n = 1), and slip interface imaging (SII; n = 1). Radiomic studies yielded encouraging results in predicting tumor growth after wait-and-scan and radiosurgery, with reported accuracies ranging from 52% to 88%, sensitivities from 13% to 95%, specificities from 50% to 94%, and area under the curves from 0.65 to 0.99. PET studies identified several promising ligands associated with tumor growth during wait-and-scan, suggesting a potential role in prognostication. DCE-MRI also demonstrated associations with tumor growth and treatment response to bevacizumab. Studies on MRE, CE-CT, and SII identified novel imaging parameters associated with tumor stiffness and adhesion. Conclusions: Several emerging imaging modalities hold potential for improving clinical outcome prognostication in VS. Techniques such as radiomics, PET, and DCE-MRI have shown promising results; however, the supporting evidence is still limited and heterogeneous. Further research is necessary to validate and refine these approaches to enhance their clinical utility.
The 2024 Update to the McDonald Criteria for Multiple Sclerosis Diagnosis: A Guide for Radiologists
Abstract BACKGROUND MYCN-amplified spinal ependymoma is a recently classified, rare, and aggressive subtype of spinal cord tumor, first defined by the 2021 WHO CNS5 classification. It predominantly affects adults in their 30s, with a slight female predominance; fewer than 50 cases have been reported worldwide. PURPOSE To characterize the molecular, imaging, and clinical features of MYCN-amplified spinal ependymomas and highlight their distinctiveness to aid in early diagnosis and therapeutic planning. METHODS We retrospectively reviewed institutional cases of MYCN-amplified spinal ependymomas and performed a literature-based analysis. Data on imaging, histopathology, molecular profiles, and clinical outcomes were examined to identify distinguishing diagnostic and prognostic features. RESULTS These tumors are typically present as intradural extramedullary masses, often in the thoracic spine, with intense contrast enhancement and prominent peritumoral edema. A lack of a clear cleavage plane with the spinal cord, early leptomeningeal, and intracranial dissemination are hallmark features. Rare reports of systemic metastases (e.g., to the humerus and paraspinal muscle) exist. Histologically, they are high-grade (WHO grade III) anaplastic ependymomas with a distinct DNA methylation profile. MYCN amplification—commonly seen in medulloblastomas and glioblastomas—drives tumor aggressiveness. Clinically, these tumors are refractory to standard treatments, with high rates of recurrence or progression within 1–2 years post-treatment. The median overall survival is approximately seven years, significantly poorer than conventional spinal ependymomas. CONCLUSION MYCN-amplified spinal ependymomas represent a rare but highly aggressive tumor subtype with unique imaging, histological, and molecular features. Early recognition is critical given rapid progression and poor prognosis. Investigational therapies targeting MYCN—such as HDAC, PARP, Aurora A-kinase, and BET inhibitors—hold promise for improved outcomes.
Loss of Enhancement in Vestibular Schwannomas Post Stereotactic Radiosurgery: Impact on Tumor Control and Serviceable Hearing
Objective: Vestibular schwannomas (VSs) treated with stereotactic radiosurgery (SRS) often show transient loss of central tumor enhancement. We hypothesized that this loss of enhancement may correlate with better tumor control on follow-up imaging. Methods: We evaluated 198 consecutive patients from a single center who met eligibility criteria. Tumor volumes on the pre-SRS and post-SRS scans were quantified along with regions of loss of enhancement on the first post-SRS study. The latter was correlated with tumor volumes at follow-up, radiation isocenter density, and loss of serviceable hearing. Results: For the entire cohort, the median loss of enhancement on the first post-SRS scan was 14% (IQR: 6 to 25) and median rate of change in tumor volume was −4.5% per year (IQR: −10.5 to 1.5). Percent loss of central enhancement showed significant negative correlation with tumor growth not only for the entire cohort (correlation coefficient: −0.18, P =0.01), but also for the subset of patients who had available imaging until at least 2 years (n=185) and 4 years (n=179) post-SRS. Loss of enhancement also strongly correlated positively with tumor volumes and number of radiation isocenters and negatively with isocenter density. Finally, patients with greater percent loss of enhancement had an increased likelihood of progression to non-serviceable hearing, although this association was not statistically significant. Conclusions: These findings suggest that loss of central tumor enhancement in VSs post-SRS may be associated with improved tumor control.
The rarely described association between pseudoaneurysm and aberrant ICA: A case series
Aberrant internal carotid artery (ICA) is a vascular anomaly in which a segment of the ICA courses through the middle ear. The association of aberrant ICAs and pseudoaneurysm formation is not well known and can be an important finding to recognize on imaging. In this series, we present three cases of aberrant ICAs having asymmetric contour deformities consistent with pseudoaneurysms diagnosed utilizing CT of the temporal bone.