Ho Sung Kim

Paramagnetic rim lesions (PRLs) are established biomarkers of chronic active inflammation in patients with multiple sclerosis (MS). Gadolinium enhancement in basal ganglia perivascular spaces (BGPVS), reflecting blood-brain barrier (BBB) permeability, represents an emerging but underexplored marker of neurovascular dysfunction. This study primarily investigated whether PRL burden is independently associated with BGPVS gadolinium enhancement. Secondarily, choroid plexus (CP) volume and the DTI-based Analysis along the Perivascular Space (ALPS) index were compared between patients with MS and healthy controls as exploratory glymphatic markers. This retrospective study (Nov 2023-Aug 2024) included patients with MS and age- and sex-matched controls who underwent 3T MRI with pre- and post-contrast T1 mapping and quantitative susceptibility mapping (QSM). PRLs were counted on QSM. Post-gadolinium BGPVS T1 enhancement, white matter hyperintensity (WMH) volume, CP volume fraction, and the ALPS index were quantified. Correlation, partial correlation adjusted for age and sex, and multivariable Poisson regression analyses with Benjamini-Hochberg false discovery rate correction identified predictors of PRL burden. A total of 144 patients with MS (mean age, 44 years ± 13 years; 105 females) and 34 controls (mean age, 49.9 years ± 16.6 years; 18 females) were evaluated. Compared with the controls, patients with MS had a lower ALPS index (1.44 ± 0.20 vs 1.56 ± 0.17; P=0.01), higher CP volume fraction (0.21% ± 0.05% vs 0.19% ± 0.04%; P=0.04), and greater BGPVS enhancement (absolute ΔT1, 92.8 ms ± 22.9 ms vs 80.7 ms ± 16.8 ms; P=0.02). The PRL count was negatively correlated with age (r=-0.378, P<0.001) and positively correlated with WMH volume (r=0.437, P<0.001) and BGPVS enhancement (r=0.219, P=0.02). After adjusting for age and sex, partial correlations confirmed significant associations between PRL count and WMH volume (r=0.477, q<0.001), CP volume fraction (r=0.297, q<0.001), and BGPVS enhancement (r=0.346, q<0.001). Multivariable Poisson regression confirmed younger age (IRR=0.91, P<0.001), higher WMH volume (IRR=1.87, P<0.001), CP volume fraction (IRR=1.46, P<0.001), and BGPVS enhancement (IRR=1.47, P<0.001) as independent predictors of PRL count. PRL burden is independently associated with increased gadolinium permeability of BGPVS, linking focal chronic active inflammation to broader blood-brain-barrier dysfunction in patients with MS.

Park YW, et al. Korean J Radiol. 2026 Nov;27(11):1075-1093. https://doi.org/10.3348/kjr.2026.1078

Yang SJ, et al. J Clin Neurol. 2026 Jan;22:e11. https://doi.org/10.3988/jcn.2025.0324

Purpose This study aims to develop automated machine learning methods to differentiate idiopathic normal pressure hydrocephalus (iNPH) from progressive supranuclear palsy (PSP) using advanced imaging features and volumetric analysis. Methods We analyzed T1-weighted 3D brain MRI scans of iNPH and PSP patients using automated component measurement acquisition and deep learning-based automated volumetric analysis. We grouped the MRI features as brainstem subgroup, volumetrics subgroup, midbrain to pons (MP) ratio subgroup (included the midbrain to pons area ratio and volume ratio), and disproportionately enlarged subarachnoid space hydrocephalus (DESH) subgroup (included the callosal angle, Sylvian fissure empty ratio, vertex region crowding ratio, and Evans’ index). Key imaging features were quantified, and statistical comparisons were conducted to identify distinguishing characteristics. Machine learning models were applied to evaluate feature effectiveness and improve diagnostic classification accuracy. Results This study analyzed 192 patients (132 iNPH, 60 PSP) and found significant differences in midbrain volume, midbrain to pons volume ratio, callosal angle, Sylvian fissure empty ratio, vertex region crowding ratio, and Evans’ index. Machine learning models, particularly the linear Support Vector Machine (SVM), achieved high diagnostic accuracy (AUROC = 0.98) in distinguishing iNPH from PSP. Volumetric analysis outperformed other feature subgroups. Conclusion The deep learning-based automated brain volumetric analysis achieved high diagnostic accuracy in distinguishing iNPH from PSP using T1-weighted brain MR images.

Purpose This study aimed to investigate the association between cerebrovascular imaging markers and glymphatic function in cognitively normal individuals. Methods This retrospective study included 574 cognitively normal participants who underwent brain magnetic resonance imaging from January to October 2023. Glymphatic function was assessed using diffusion tensor image analysis along the perivascular space index (ALPS-index). Cerebrovascular imaging markers, including white matter hyperintensity (WMH) burden, cerebral microbleeds (CMBs), and choroid plexus volume (CPV), were quantified using automated segmentation methods. The presence of lacunes in the basal ganglia or old infarcts in other areas was visually determined. Associations between cerebrovascular markers and ALPS-index were analyzed using multivariable regression and partial correlation analyses. Results The mean age of the included participants was 68.9 ± 10.4 years (male, 40.9%; hypertension, 43.7%; diabetes, 20.4%; Mini-Mental State Examination [MMSE] score, 27.6 ± 1.6). A lower ALPS-index, reflecting impaired glymphatic clearance, was significantly associated with higher WMH burden (β=–0.231, p < 0.001), increased CPV fraction (β=–0.234, p < 0.001), and a greater number of deep CMBs (β=–0.087, p = 0.038). The participants with basal ganglia lacunes (ALPS-index: 1.32 ± 0.19), old infarcts other than basal ganglia (ALPS-index: 1.34 ± 0.19), or both (ALPS-index: 1.27 ± 0.19) had significantly lower ALPS-indices than those without these conditions (ALPS-index: 1.43 ± 0.21; all, p < 0.001). Conclusion Cerebrovascular imaging findings are significantly associated with glymphatic dysfunction in cognitively normal individuals, highlighting the need for further studies on glymphatic-targeted interventions in cerebrovascular disease prevention.

Gross total resection of noncontrast-enhanced tumor was an independent prognostic factor for longer overall survival, regardless of age and O⁶-methylguanine DNA methyltransferase promoter methylation status, in patients with isocitrate dehydrogenase wild-type glioblastoma.

Amyloid-related imaging abnormalities (ARIA) are key safety considerations in anti-amyloid-β (Aβ) immunotherapy. ARIA can be categorized into 2 types: ARIA characterized by edema and effusion (ARIA-E) or microhemorrhages and superficial siderosis (ARIA-H). In this study, we assessed the incidence of ARIA in phase 3 randomized controlled trials (RCTs) of anti-Aβ immunotherapy and compared the incidence among different agents and APOE ε4 carrier status. PubMed and Embase databases were searched for phase 3 RCTs of anti-Aβ immunotherapy published on or before May 23, 2024. The inclusion criteria were phase 3 trials of anti-Aβ immunotherapy for mild cognitive impairment due to Alzheimer disease (AD) or mild AD dementia, with sufficient data on ARIA-E/H. The pooled incidences of ARIA and subgroup analyses according to various agents and APOE ε4 carrier status were calculated. A sensitivity analysis excluding outliers was performed. The pooled odds ratio (OR) of ARIA-E according to the APOE ε4 carrier status was also calculated. Nine phase 3 RCT cohorts from 8 eligible studies were identified, analyzing data from 6,315 patients. The pooled incidence of ARIA-E was 9.5% (95% CI 2.8%-27.3%), and the adjusted pooled incidence of ARIA-E was 25.5% (95% CI 20.4%-31.8%) in the sensitivity analysis. The pooled incidence of symptomatic ARIA-E was 6.7% (95% CI 3.5%-12.5%) and that of severe ARIA-E was 3.5% (95% CI 13.8%-8.4%). The pooled incidence of ARIA-H was 17.8% (95% CI 11.0%-27.5%), with the incidence of superficial siderosis was 9.3% (95% CI 6.1%-13.9%). The pooled incidence of isolated ARIA-H was 8.7% (95% CI 7.6%-10.1%). Subgroup analysis showed that homozygous APOE ε4 carriers had significantly higher odds of developing ARIA-E (OR 5.6, 95% CI 3.8-8.2, p < 0.001) than noncarriers. Heterozygous APOE ε4 carriers also had significantly higher odds of developing ARIA-E (OR 1.9, 95% CI 1.5-2.4, p < 0.001) than noncarriers. Although limited by small sample size and cohort-level data, our meta-analysis shows the adjusted pooled incidence of ARIA-E was 25.5% and the pooled incidence of ARIA-H was 17.8% in the recent phase 3 RCTs of anti-Aβ immunotherapy. Homozygous APOE ε4 carriers have a 5.6-fold higher risk of developing ARIA-E than noncarriers.

정소영, et al. J Korean Soc Radiol. 2025 Jan;86(1):17-33. https://doi.org/10.3348/jksr.2024.0140