Radiology最新文献

Background Synaptic loss is an important factor in Alzheimer disease (AD); however, blood assays that conveniently and rapidly reflect changes in synaptic density are lacking. Purpose To correlate multiple potential synaptic blood markers with synaptic density measured using ¹⁸F-SynVesT-1, a fluorine 18 (¹⁸F)-labeled radiotracer, brain PET and to explore the independent associations between these markers and synaptic density. Materials and Methods This prospective study included 50 cognitively unimpaired (mean age, 65.0 years ± 8.3 [SD]; 37 female) participants and 70 participants with cognitive impairment (mean age, 69.5 years ± 7.9; 43 female) from the Memory Clinic of Shanghai Jiao Tong University Affiliated Ruijin Hospital and communities in Shanghai. Amyloid-β (Aβ) and tau were assessed using ¹⁸F-florbetapir and ¹⁸F-MK6240 PET/CT. Synaptic density was evaluated with ¹⁸F-SynVesT-1 PET/MRI. Pearson correlation analysis was used to investigate relationships of plasma (Aβ42/40 ratio, phosphorylated tau 181 [p-tau-181], glial fibrillary acid protein [GFAP], neurofilament light) and serum (C-reactive protein, tumor necrosis factor-α, α-synuclein, neurogranin, active plasminogen activator inhibitor-1, tissue plasminogen activator) biomarkers with synaptic density. Linear regression models and mediation analysis were used to explore effects of other AD-related pathologies on these relationships. Results Correlations were observed between increased p-tau-181 and GFAP and decreased synaptic density in global cortex (r_p-tau-181 = -0.352, r_GFAP = -0.386; both P < .001) and hippocampus (r_p-tau-181 = -0.361, r_GFAP = -0.369; both P < .001) at ¹⁸F-SynVesT-1 PET/MRI. The relationships between p-tau-181 and GFAP with ¹⁸F-SynVesT-1 PET/MRI persisted after controlling for plasma Aβ42/40 ratio, Aβ PET, or cortical thickness (P value range, <.001-.01). This association disappeared after controlling for tau PET (P value range, .08-.83). Conclusion Plasma p-tau-181 and GFAP are closely associated with synaptic density measured using ¹⁸F-SynVesT-1 PET/MRI, with the relationship primarily influenced by tau accumulation rather than Aβ deposition or cortical thickness. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Giannakopoulos in this issue.

Background Breast nonmass lesions (NMLs) are observed at screening and diagnostic US. However, knowledge is limited on imaging features of NMLs at screening US. Purpose To identify features of NMLs at screening US that are suspicious for malignancy based on mammographic findings. Materials and Methods This retrospective, multicenter study included asymptomatic women who underwent screening US between January 2012 and December 2019. Eligible women had NMLs at US, concurrent screening mammography, and record of a final diagnosis. Logistic regression analyses were used to identify factors associated with malignancy. The diagnostic performance of each sonographic feature according to mammographic findings was calculated. A reader study was performed to assess interreader agreement for sonographic features. Results Among 993 NMLs in 993 patients (mean age, 50 years ± 9 [SD]), 914 (92.0%) were benign and 79 (8.0%) were malignant. Mean size was larger for malignant NMLs than for benign NMLs (2.6 cm ± 1.1 vs 1.9 cm ± 0.8; P < .001). In multivariable analysis, associated calcifications (odds ratio [OR], 21.6 [95% CI: 8.0, 58.2]; P < .001), posterior shadowing (OR, 6.9 [95% CI: 2.6, 18.4]; P < .001), segmental distribution (OR, 6.2 [95% CI: 2.7, 14.4]; P < .001), mixed echogenicity (OR, 5.0 [95% CI: 1.8, 14.0]; P < .001), and size (OR, 1.5 [95% CI: 1.1, 2.1]; P = .01) at US were associated with malignancy. Associated calcifications, posterior shadowing, segmental distribution, and mixed echogenicity showed positive predictive values (PPVs) of 44%, 22%, 22.9%, and 16.6%, respectively. Having a negative mammogram was associated with a lower malignancy rate (2.8% vs 28.8%) and lower PPVs for sonographic features (0.7%-10.4% vs 24%-55%) than having a positive mammogram. Interreader agreement for sonographic features was good to excellent (Fleiss κ 95% CI lower bound range, 0.63-0.81). Conclusion Calcifications, posterior shadowing, segmental distribution, and mixed echogenicity associated with NMLs can be considered suspicious features for malignancy at screening US. As malignancy rates and PPVs differ according to mammographic abnormalities, combined assessment is mandatory. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Grimm in this issue.

Background Patients with neuromyelitis optica spectrum disorder (NMOSD) are often seropositive for antibodies against aquaporin-4 (AQP4). The importance of MRI monitoring in this disease requires evaluation. Purpose To profile MRI features from a large international cohort with AQP4 immunoglobulin G (IgG)-seropositive NMOSD (from the Parallel MRI in NMOSD [PAMRINO] study) and to evaluate and confirm existing knowledge regarding the incidence, location, and longitudinal development of characteristic lesions in the central nervous system associated with AQP4-IgG-seropositive NMOSD. Materials and Methods In this retrospective study (from August 2016 to January 2019), MRI and clinical data were collected from 17 NMOSD expert sites in 11 countries across four continents. Clinical features and lesions identified at cross-sectional and longitudinal MRI were assessed. No formal statistical tests were used to compare observations; however, means, SDs, and 95% CIs are reported when evaluating lesion frequencies. Results Available T1-weighted and T2-weighted MRI scans in patients with AQP4-IgG-seropositive NMOSD (n = 525) were read. Among the 525 patients, 320 underwent cerebral MRI examinations with T2-weighted hyperintense cerebral (264 of 320; 82.5%), cerebellar (44 of 320; 13.8%), and brainstem (158 of 321 [49.2%], including one lesion observed at cervical spinal cord [SC] MRI) lesions. Lesions in the optic nerves, analyzed from 152 MRI examinations, were mainly found in the central (81 of 92; 88%) and posterior (79 of 92; 86%) sections (bilaterally in 39 of 92; 42%). Longitudinally extensive transverse myelitis was the predominant SC lesion pattern (upper compartment from 322 MRI examinations, 133 of 210 [63.3%]; and lower compartment from 301 MRI examinations, 149 of 212 [70.3%]). However, nonlongitudinal extensive transverse myelitis lesions were also observed frequently (105 of 210; 50.0%) in the cervical SC. Clinical data (n = 349; mean age, 44 years ± 14 [SD]; 202 female patients) and acute lesions at contrast-enhanced (CE) MRI (n = 58, performed within 30 days of the last attack) were evaluated. CE lesions were detected in the cerebrum (eight of 13; 62%), optic nerves (14 of 19; 74%), or chiasm (three of four; 75%) within 15 days of any relapse. In the upper SC (29 of 44; 66%), CE lesions were frequently observed up to 20 days after a clinical myelitis event. Conclusion A high incidence of abnormal brain MRI examinations and nonlongitudinal extensive SC lesions was found in patients in PAMRINO with AQP4-IgG-seropositive NMOSD. © RSNA, 2024 Supplemental material is available for this article.

Background The clinicopathologic-radiologic and prognostic characteristics of intratumoral fat in hepatocellular carcinoma (HCC) are critical for personalized treatment but remain understudied. Purpose To investigate the clinicopathologic-radiologic associations and prognostic implications of MRI-assessed intratumoral fat in HCCs. Materials and Methods This retrospective cohort study included consecutive adult patients who underwent resection for solitary HCCs and preoperative contrast-enhanced MRI from two tertiary-care hospitals in East Asia (March 2011 to December 2021) and Western Europe (September 2012 to December 2019). MRI scans were independently evaluated by three radiologists at each hospital. Based on Liver Imaging Reporting and Data System (LI-RADS) version 2018, intratumoral fat was defined as "fat in mass more than adjacent liver," and the homogeneous subtype was defined as intratumoral fat "in absence of mosaic and nodule-in-nodule architecture." Recurrence-free survival (RFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using the log-rank test. Cox regression analyses were conducted to identify factors associated with RFS and OS. Results A total of 933 patients were included in the Asian (n = 736; median age, 53 years [IQR, 45-62 years]; 626 male) and European (n = 207; median age, 64 years [IQR, 55-70 years]; 161 male) cohorts. MRI-assessed intratumoral fat was detected in 30% (215 of 726) and 31% (64 of 207) of patients in the Asian and European cohorts, respectively (P = .72). In both cohorts, the steatohepatitic subtype, nonperipheral washout, enhancing capsule, and mosaic architecture were more frequent in tumors with intratumoral fat (P value range, <.001 to .04). Intratumoral fat in general was not associated with RFS or OS in either cohort (P value range, .48-.97). However, in the Asian cohort, homogeneous intratumoral fat was associated with longer RFS (hazard ratio [HR], 0.60; P = .009) and OS (HR, 0.33; P = .008) in multivariable Cox regression analyses. Conclusion MRI-assessed intratumoral fat was more frequent in steatohepatitic HCCs and associated with nonperipheral washout, enhancing capsule, and mosaic architecture. Although intratumoral fat was generally nonprognostic, homogeneous intratumoral fat was associated with longer RFS and OS in the Asian cohort. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Harmath in this issue.