Radiology最新文献

Background Accurate recognition of nonmass lesions (NMLs) at breast US is essential for ensuring consistent diagnostic performance. Purpose To assess agreement in classifying lesions as masses or NMLs at US and to identify features that support confidence in NML identification. Materials and Methods This retrospective single-center study included patients who underwent US-guided biopsy of lesions from January to June 2021. Four breast radiologists participated in the study to assess interreader agreement in classifying lesions as either masses or NMLs. An additional radiologist reclassified NMLs that had conflicting interpretations, categorizing them as either definite NMLs or controversial NMLs. Features associated with definite NML judgments were evaluated by means of logistic regression analysis. Results Among 1067 lesions in 912 women (mean age, 53.4 years ± 12.1 [SD]), 11% (121 lesions) were classified as definite NMLs and 7% (80 lesions) as controversial NMLs. The agreement was moderate to substantial (κ = 0.534-0.638), with a concordance rate of 84%-91%. The odds of being classified as a definite NML were low for lesions smaller than 1 cm or subtle architectural distortion (odds ratio [OR], 0.269 [95% CI: 0.112, 0.647]; P = .003) and high for cases with echogenic foci associated with calcifications at mammography (OR, 2.679 [95% CI: 1.130, 6.354]; P = .03) and microcysts (OR, 3.578 [95% CI: 1.236, 10.360]; P = .02). The presence of corresponding findings at mammography (P = .27) or MRI (P > .99) was comparable between the definite and controversial NML groups. Conclusion Interreader agreement for classifying lesions at US as masses or NMLs was moderate to substantial, with high concordances rates. Smaller lesions or subtle architectural distortions were less likely to be consistently classified as NMLs, whereas lesions with echogenic foci associated with calcifications at mammography and microcysts were more likely to be consistently classified as NMLs. © RSNA, 2025 See also the editorial by Hooley in this issue.

Background Evaluating the extent of invasiveness for nonsolid nodules (NSNs) in patients with lung adenocarcinoma at CT could affect clinical decision-making but can be challenging. Purpose To investigate CT characteristics of NSNs associated with pathologic invasiveness and to develop a radiologic ternary classification model for differentiating among preinvasive lesions, minimally invasive adenocarcinoma (MIA), and invasive adenocarcinoma (IAC). Materials and Methods This retrospective study enrolled patients with pathologically confirmed lung adenocarcinoma and suspicious malignant NSNs measuring 3.0-30.0 mm on preoperative CT scans between January 2012 and June 2024. For each NSN, the size, location, margin, shape, nodule CT attenuation, uniformity of density, lobulation sign, reticulation sign, intranodular vessels, bubble-like lucency sign, air bronchogram sign, and pleural retraction sign were independently evaluated by two radiologists blinded to clinical information and pathology results. Univariable ordinal regression and partial proportional odds model analyses were performed. Three nested mixed-effects models were compared in differentiating pathologic invasiveness subtypes. Results This study included 1683 patients (median age, 53 years [IQR, 45-61 years]; 1145 women) with 2125 NSNs. Partial proportional odds model analysis demonstrated that the independent radiologic factors for predicting pathologic invasiveness were average diameter (preinvasive lesion vs MIA: odds ratio [OR], 1.34; MIA vs IAC: OR, 1.54), intranodular vessels (one vessel: OR, 2.22; two vessels: OR, 3.06; more than two vessels: OR, 25.16), mean CT attenuation (OR, 1.54), heterogeneous density (OR, 2.45), spiculation (OR, 1.72), lobulation (OR, 1.50), pleural retraction (OR, 1.43), bubble lucency (OR, 1.81), and air bronchogram (OR, 1.74). The overall diagnostic performance of the radiologic ternary classification model was excellent (C index, 0.92; 95% CI: 0.91, 0.92). Incorporating mean CT attenuation and morphologic features improved model performance in predicting NSN pathologic invasiveness compared with using nodule diameter alone (all P < .001). Conclusion The radiologic ternary classification model demonstrated excellent diagnostic performance in differentiating among preinvasive lesions, MIA, and IAC in NSNs detected on CT images. © RSNA, 2025 Supplemental material is available for this article. See also the editorial by Arita and Schalekamp in this issue.

Background T2-weighted MRI is the standard for visualizing MRI-guided focused ultrasound (MRgFUS) thalamotomy lesions in essential tremor (ET) and tremor-dominant Parkinson disease (TDPD); however, chronic lesion visibility is often variable, including low-contrast or undetectable lesions, complicating long-term assessment, especially in patients with tremor recurrence. Purpose To determine whether T1/T2-weighted ratio imaging improves the lesion normalized contrast (NC) of chronic MRgFUS thalamotomy-induced lesions compared with T2-weighted imaging. Materials and Methods This retrospective study included patients with ET or TDPD who underwent MRgFUS thalamotomy (January 2019 to November 2023). Lesion NC was quantified on T1/T2-weighted ratio and T2-weighted images at the 6-month follow-up. Between-modality NC comparisons used paired t tests. Similar analyses in patients with tremor recurrence used the Wilcoxon signed rank test. Between-evaluator agreement for lesion segmentation was assessed by comparing the average intraclass correlation coefficients (ICCs) via bootstrapping (95% CI for the difference). Spearman-skipped correlation analysis was performed to assess whether lesion overlap with the ventrolateral posterior ventral thalamic nucleus (VLpv) correlated with tremor relief from baseline to the 6-month follow-up. Results A total of 54 patients were included, 27 with ET and 27 with TDPD (mean age, 71.3 years ± 9.2 [SD]; 32 male patients). Lesion NC was higher for T1/T2-weighted ratio images (mean, 36.3% ± 18.2) than for T2-weighted images (mean, 19.2% ± 8.9) (P < .001). Similar results were found in patients with tremor recurrence (median NC at T1/T2-weighted ratio imaging, 45.2% [IQR, 14%-64%]; median NC at T2-weighted imaging, 25.3% [IQR, 9%-31%]). T1/T2-weighted ratio imaging had higher between-evaluator agreement (ICC = 0.94) than T2-weighted imaging (ICC = 0.81; 95% CI for the difference: 0.01, 0.32). Lesion VLpv overlap was positively correlated with tremor relief in patients with ET (T2-weighted imaging: ρ = 0.47 [95% CI: 0.10, 0.74]; T1/T2-weighted ratio: ρ = 0.53 [95% CI: 0.13, 0.76]) and TDPD (T2-weighted imaging: ρ = 0.42 [95% CI: 0.08, 0.67]; T1/T2-weighted imaging ratio: ρ = 0.48 [95% CI: 0.17, 0.66]). Conclusion T1/T2-weighted ratio imaging substantially improved chronic lesion NC compared with T2-weighted imaging, reducing interobserver variability and measurement error. © RSNA, 2025 Supplemental material is available for this article.