Radiology最新文献

Background Percutaneous thermal ablation (PTA), including radiofrequency and microwave ablation, has been established as a curative therapy for small malignant liver neoplasms; yet, as clinical indications expand, overall safety remains good, although the exact incidence of complications varies among studies. Purpose To determine updated benchmarks for procedure-related mortality and major adverse events (AEs) after PTA of malignant liver tumors. Materials and Methods In this systematic review and single-proportion meta-analysis of patients who underwent thermal ablation of malignant liver tumors, Cochrane, MEDLINE, and Embase were searched for prospective randomized or cohort studies published from January 2007 to September 2022 that reported AEs after radiofrequency or microwave ablation of three or fewer liver tumors measuring 5 cm or smaller, over at least 90 days of follow-up. Two reviewers independently screened the studies, extracted data, and assessed the risk of bias. Pooled proportions of significant AEs (ie, Society of Interventional Radiology grades C-E), including 90-day procedure-related mortality, were calculated with random-effects models. Results Forty-nine studies comprising 4149 patients and 4636 ablations met the inclusion criteria. The pooled proportion of significant AEs was 3.0% (86 of 3149 patients; 95% CI: 2.50, 3.67; I² = 0%). The 90-day procedure-related mortality rate was 0.01% (one of 4149 patients; 95% CI: 0.007, 0.014). The AE rates did not differ significantly between radiofrequency and microwave ablation (3.21% vs 2.65%; P = .41) or between hepatocellular carcinoma and metastatic tumors (2.94% vs 3.91%; P = .85). Conclusion PTA of malignant liver tumors is associated with near-zero 90-day mortality and a 3% major complication rate. © RSNA, 2026 Supplemental material is available for this article. See also the editorial by Bettmann in this issue.

Background The management of incidental adnexal lesions encountered at CT depends on the diagnosis, but little evidence supports CT diagnosis of most adnexal lesion types. Purpose To evaluate the interreader agreement and CT diagnosis of incidentally discovered adnexal lesions. Materials and Methods This institutional review board-approved, multi-institutional, multireader retrospective study conducted from January 1, 2022, to June 30, 2023, included patients who had malignant ovarian lesions with metastases (n = 8) and without metastases (n = 8), simple cysts (n = 6), dermoids (n = 9), hydrosalpinx (n = 5), benign cystadenomas and/or cystadenofibromas (n = 10), hemorrhagic cysts (n = 8), endometriomas (n = 6), ovarian fibromas (n = 5), leiomyomas (n = 5), and peritoneal inclusion cysts (n = 5) detected at CT. Nine members of the Society of Abdominal Radiology Uterine and Ovarian Cancer Disease-Focused Panel, blinded to the final diagnosis, independently reviewed the CT images and used the American College of Radiology white paper to determine the most likely diagnosis. A 2 × 2 factorial random-effects model was used to calculate the mean adjusted accuracy and disparity among the readers. Interreader agreement was calculated using a Gwet AC1 test. Results In total, 75 patients (mean age, 50 years ± 16 [SD]) were included. The mean adjusted accuracy and interreader agreement were highest for dermoids (99% and 0.97, respectively), malignant ovarian lesions with metastases (94% and 0.90), and simple cysts (86% and 0.64). The mean adjusted accuracy for all other lesion types was less than 72%, with fair to moderate interreader agreement. Overall, readers more accurately diagnosed malignant lesions (82%) than benign lesions (52%) (P < .001). Readers recorded a benign diagnosis when a malignant lesion was present 28% of the time (20 of 72) (P < .001) when there were no metastases. Conclusion Readers' mean adjusted accuracy was greatest for dermoids, malignant ovarian lesions with metastases, and simple cysts at CT, with substantial to almost perfect interreader agreement; all other lesions were challenging, and a substantial number of malignant ovarian lesions were misdiagnosed as benign. © RSNA, 2026.

Background Although energy-integrating detector (EID) CT remains the standard in diagnosing and monitoring lung cancer, it has limitations compared with photon-counting CT (PCCT). However, the role of low-dose PCCT in evaluating lung cancer remains unexplored. Purpose To compare the diagnostic quality of chest CT images from PCCT with a low radiation dose and a low injection rate, volume, and concentration of contrast agent (hereafter, a "quadruple-low protocol") with that of EID CT in patients with lung cancer. Materials and Methods This retrospective study included patients with lung cancer undergoing PCCT or EID CT between July 2024 and September 2024. Patients underwent PCCT with the low radiation dose plus reduced contrast agent protocol (quadruple-low protocol: 2.0 mL/sec injection rate, 1.0 mL/kg of 320 mg of iodine per milliliter) and EID CT with a conventional protocol. Two radiologists independently evaluated the subjective image quality and lesion imaging features. Lesion and parenchymal metrics (attenuation, signal-to-noise ratio [SNR], and contrast-to-noise ratio [CNR]) were also assessed. Data were compared using the Student t test, Mann-Whitney U test, or multivariable regression. Sensitivity analysis was performed using propensity score matching. Results Among 425 participants (mean age, 61 years ± 9.5 [SD]; 273 men), PCCT reduced radiation dose by 55% (mean effective dose, 3.49 mSv ± 0.91 vs 7.82 mSv ± 2.15; P < .001) while lowering contrast agent injection rate, volume, and concentration by 33% (P < .001), 22% (P < .001), and 9% (P < .001), respectively. PCCT reduced the incidence of contrast-induced nephropathy (CIN) compared with EID CT (0% [0 of 120] vs 7.9% [24 of 305], P = .02). PCCT also exhibited higher objective SNR and CNR in lung lesions and parenchyma, with superior subjective image quality scores and increased diagnostic confidence for imaging features (all adjusted P < .001). Results remained consistent in sensitivity analysis. Conclusion Compared with EID CT, PCCT with a quadruple-low protocol reduced the incidence of CIN and enhanced image quality and diagnostic confidence in imaging features in patients with lung cancer. © RSNA, 2026 Supplemental material is available for this article.

Background Diffusion-tensor image (DTI) analysis along the perivascular space (ALPS) is a noninvasive but not well-validated method proposed to evaluate glymphatic function. Purpose To assess ALPS indexes across participant groups and compare them with measures of cerebrospinal fluid (CSF) tracer enrichment and clearance obtained by intrathecal contrast-enhanced MRI (glymphatic MRI [gMRI]). Materials and Methods This secondary analysis of a prospective observational study included participants who underwent clinical work-up for CSF disorders from September 2015 to December 2019. MRI scans were acquired before injection and 24 and 48 hours after intrathecal injection of 0.5 mmol of gadobutrol. DTI scans were preprocessed and segmented using the FMRIB Software Library. Intrathecal contrast-enhanced MRI (ie, gMRI) scans were registered to the baseline T1-weighted image, and cortex and white matter (WM) were segmented with FreeSurfer. ALPS indexes were compared with relative changes in normalized T1-weighted signal intensity at 24 and 48 hours in regions of the cortex, subcortical WM, and deep WM where the ALPS regions of interest are located by using regression analysis. Results A total of 56 participants were included (mean age, 48 years ± 20 [SD]; 36 women): 16 with idiopathic normal pressure hydrocephalus (iNPH), 10 with arachnoid cysts, 11 with idiopathic intracranial hypertension, and 19 reference participants. The ALPS index was lower in the iNPH group than in the reference group (ALPS index, 1.26 and 1.68, respectively; P < .001). Across groups, the ALPS index and degree of CSF tracer enrichment at 24 hours in deep WM were negatively associated (β = -48; P < .001). However, mean tracer enrichment in the ALPS regions of interest was low (10%), in some participants close to 0, whereas enrichment in the cortex ranged from 68% to 81%. Across groups, there was no evidence of associations between the ALPS index and measures of CSF tracer dynamics at 48 hours in any region (|β| ≤ 8; P ≥ .55). Conclusion CSF tracer enhancement in the ALPS regions of interest was sparse across groups, and the association between the ALPS index and gMRI markers of glymphatic function was limited. © The Author(s) 2026. Published by the Radiological Society of North America under a CC BY 4.0 license. Supplemental material is available for this article.

Background A novel super-resolution deep learning reconstruction (SR-DLR) algorithm, trained using data acquired with ultra-high-resolution CT, can potentially enhance spatial resolution in coronary CT angiography (CCTA), improving stenosis assessment; however, evidence is limited. Purpose To compare the performance of SR-DLR versus hybrid iterative reconstruction (HIR) in assessing coronary stenosis, using invasive coronary angiography (ICA) as the reference standard, and to explore the potential impact on patient-level Coronary Artery Disease Reporting and Data System (CAD-RADS) classification. Materials and Methods From September 2023 to November 2024, patients who underwent clinically indicated CCTA and ICA within a 2-month interval were prospectively enrolled at 10 hospitals across China. CCTA images were reconstructed with both HIR and SR-DLR, and percentage diameter stenosis (PDS) of calcified, noncalcified, and mixed plaques was quantified. Participant-level CAD-RADS category was determined based on the highest-grade stenosis. Using ICA as the reference standard, diagnostic performance of HIR and SR-DLR in detecting significant stenosis (50% or greater stenosis) was compared using the area under the receiver operating characteristic curve (AUC). Results The study included 204 individuals (mean age, 64.3 years ± 9.1 [SD]; 137 male participants) with 605 plaques (175 calcified, 140 noncalcified, 290 mixed). Median PDS for calcified plaques was lower with SR-DLR than with HIR (58% [IQR, 44%-71%] vs 63% [IQR, 53%-85%]; P < .001), with no evidence of a difference in median PDS for noncalcified (P = .09) or mixed (P = .40) plaques. Forty-one individuals were assigned a different CAD-RADS category with SL-DLR relative to HIR: 25 downgraded and 16 upgraded. SR-DLR outperformed HIR in detecting significant stenosis at the lesion level (AUC, 0.97 [95% CI: 0.96, 0.98] vs 0.90 [95% CI: 0.87, 0.92]; P < .001) and participant level (AUC, 0.90 [95% CI: 0.82, 0.98] vs 0.79 [95% CI: 0.70, 0.89]; P < .001). Conclusion SR-DLR outperformed HIR for coronary stenosis assessment and led to 20% (41 of 204) participant-level CAD-RADS reclassification. © The Author(s) 2026. Published by the Radiological Society of North America under a CC BY 4.0 license. Chinese Clinical Trial Registry no. ChiCTR2300075364 Supplemental material is available for this article.

Background Hepatocellular carcinoma (HCC) surveillance typically involves US, although gadoxetate-enhanced MRI may improve sensitivity. Identifying factors impacting image quality is essential, but comparative data between US and MRI are lacking. Purpose To compare image quality and its determinants in gadoxetate-enhanced MRI versus US in participants with cirrhosis who are undergoing HCC screening in a prospective bicenter study. Materials and Methods In a secondary analysis of a prospective bicenter North American HCC screening study (September 2020 to May 2023), participants with cirrhosis underwent contemporaneous gadoxetate-enhanced MRI and liver US. Two independent observers evaluated MRI scans for dynamic phase motion, hepatobiliary phase liver uptake, and diffusion-weighted imaging quality. Sums of these assessments were trichotomized into MRI scores (MR-A: no or minimal limitations; MR-B: moderate limitations; and MR-C: severe limitations). US quality was scored per the Liver Imaging Reporting and Data System (US-A: no or minimal limitations; US-B: moderate limitations; and US-C: severe limitations). Clinical factors and quality were assessed using univariable and/or multivariable analyses. Proportions of quality scores were compared (McNemar χ² test). Results Among the 245 participants with cirrhosis (median age, 61 years; 133 men), MRI quality scores were classified as MR-A in 80.4% (197 of 245 participants), MR-B in 18.4% (45 of 245 participants), and MR-C in 1.2% (three of 245 participants), whereas available US visualization scores were classified as US-A in 24.2% (58 of 240 participants), US-B in 61.7% (148 of 240 participants), and US-C in 14.1% (34 of 240 participants). The proportion of examination scores with no or minimal limitations was higher for MRI than US in 240 participants with both set of scores (P < .001). Obesity (body mass index ≥ 30, calculated as weight in kilograms divided by height in meters squared) reduced quality for both modalities (MRI univariable odds ratio [OR], 4.20 [95% CI: 1.20, 22.6], P = .01; US OR, 2.50 [95% CI: 1.00, 6.00], P = .04), not confirmed at multivariable analysis. Child-Pugh score of B and/or C reduced MRI quality at univariable (OR, 2.60 [95% CI: 1.05, 6.30]; P = .03) and multivariable (adjusted OR, 3.95 [95% CI: 1.50, 10.42]; P = .006) analysis. Conclusion Most participants undergoing HCC screening had excellent MRI quality even when US was limited. Quality was adversely affected by obesity (both modalities) and Child-Pugh score (MRI only). ClinicalTrials.gov Identifier: NCT04539717 © The Author(s) 2026. Published by the Radiological Society of North America under a CC BY 4.0 license. Supplemental material is available for this article.