Empyema incidence is rising, with high mortality, and patients frequently requiring invasive procedural management. Early intervention is linked with reduced procedural invasiveness and rates of general complications. CT can aid diagnostic certainty and guide management approaches, but the value of CT timing on outcomes remains unclear. Describe the association between CT timing and outcomes for patients diagnosed with Empyema who present through the emergency department. A retrospective cohort study of adult empyema patients was performed using TriNetX data (2009 to 2025). Patients were stratified based on timing of CT thorax: patients who received CT the same day as an emergency room (ER) admission (early) versus patients who received CT 1 to 3 days after ER admission (late). Outcomes were assessed at 30 days and included mortality, surgical intervention of any of the lungs, pleura, trachea, or bronchi, ER readmission, and requirement of ventilator support. Kaplan-Meier survival, logistic regression, and frequency-based outcome analyses were performed. After matching for demographics, both cohorts included 2250 patients. The mean age was 44 years, and patients were 66% White and 60% male. There were no significant differences in vital signs or leukocyte count between cohorts. Early CT patients experienced significantly lower mortality (98.2% vs. 96.3%; P=0.0002; HR=0.488), a lower risk of invasive surgery (26.7% vs. 40.4%; P<0.0001; RR=0.661), and reduced risk for requiring ventilator support (8.9% vs. 11.7%; P=0.0017; HR=0.748). Early CT was associated with increased all-cause ER readmission (23.47% vs. 17.07%, P<0.0001; RR=1.375). Pyothorax management is of ongoing interest given associated morbidity/mortality, high treatment costs, and frequency of invasive procedures. Early CT is associated with decreased mortality, decreased invasive surgical requirement, decreased ventilator dependence, and increased all-cause 30-day ER readmission.

To assess the impact of split-bolus (SB) single scan CT on the conspicuity of clear cell renal cell carcinoma (ccRCC) metastases compared with single-bolus injection. This retrospective cohort study included consecutive patients with histologically proven metastatic ccRCC who underwent both SB and single-bolus portal venous abdominal CT within 6 months between 2017 and 2022 in a single tertiary center. SB CT utilized BMI-adjusted contrast dose and kVp (80 to 120) with concurrent arterial and portal venous phases. Single bolus CT utilized BMI-adjusted contrast dose at 120kVp at the portal venous phase. Wilcoxon rank test compared the conspicuity of metastases between the protocols. Of the 47 patients, 80.9% were male, with a mean age of 67±10.4 years and a BMI of 27.1±5.7. There were 48 paired CTs performed with a median interval of 93 days. Contrast dose was 143±27ml for SB and 108±26ml for single-bolus ( P <0.001). Sixty-six metastases were analyzed, with an average size of 2cm: 48.5% in the pancreas, 28.8% in skeletal muscle, and 22.7% in the liver. The median contrast-to-noise ratio (CNR) was higher with SB compared with single-bolus for all metastases (3.0 vs. 1.4), pancreatic metastases (2.7 vs. 1.4), muscle metastases (5.2 vs. 2.0), and liver metastases (2.8 vs. 0.9), all P <0.001. SB scan provides dramatically higher conspicuity of ccRCC metastases as compared with single-bolus portal venous CT.

Coronary computed tomography angiography (CTA) plays a pivotal role in the diagnosis of coronary heart disease in elderly hypertensive patients. This study aimed to investigate the hemodynamic changes in terms of dynamic characteristics, magnitude, and duration following intravenous bolus injection of iodinated contrast media. Thirty-two medicated hypertensive patients and 32 nonhypertensive patients underwent Iopromide 370-mediated coronary CTA examination (registration number: ChiCTR2300070704). Hemodynamic parameters were determined at 6 predefined time points from 1 minute before injection to 30 minutes postinjection, using a noninvasive hemodynamic monitoring system. Continuous variables were compared using an independent-samples t test. Categorical data were compared using the χ2 test or a nonparametric test based on data distribution. Repeated measures data were analyzed using repeated measures analysis of variance. The patterns of hemodynamic change were comparable between groups, with most indicators showing a transient increase followed by recovery to baseline. The magnitude of change was more pronounced in the hypertensive group, with most indicators fluctuating within 10% of baseline values. All hemodynamic values during injection correlated well with baseline levels in both groups, with Pearson correlation coefficients ranging from 0.61 to 0.87. No acute allergic-like reactions were observed, and there was no statistically significant difference in physiological responses between groups. Our findings indicate that Iopromide 370 has favorable safety and tolerability. Greater clinical caution may be warranted for elderly hypertensive patients with cardiovascular comorbidities.

Early prediction of remnant liver growth after portal vein embolization (PVE) would enable earlier surgery in patients with resectable liver malignancy, decreasing the risk of tumor progression. This study aims to demonstrate the feasibility of 4D flow MRI to detect changes in portal blood flow before and after PVE and determine whether 4D flow MRI can predict hypertrophy of nonembolized liver lobes (future liver remnant) in a porcine model. Thirteen juvenile pigs were included in this prospective study. In 11 pigs, 2 of the 4 portal vein branches were selectively embolized using polyvinyl alcohol particles. Two pigs served as controls. All animals were imaged before, 1 hour, and 1 and 2 weeks after PVE using 4D flow and T1-weighted 3D spoiled gradient-echo MRI. Flow measurements were correlated with liver volumetry measurements. The predictive value of flow changes immediately after PVE for future liver remnant hypertrophy at 2 weeks was estimated using linear mixed-effect model analysis. Twelve pigs completed the study. One treatment pig died from complications of anesthesia. Immediately after PVE, relative flow in the 2 embolized portal vein branches decreased from 17.0±2.1% to 3.4±2.1% of total portal flow, respectively. Relative flow increased from 16.6±3.8% to 32.6±3.8% in the remaining 2 nonembolized portal vein branches supplying the future liver remnant. Each 1% increase in relative blood flow directly after the procedure predicted a 4.8±0.7cm 3 (estimate±SE) increase in volume of the future liver remnant at 2 weeks ( P <0.0001). Conversely, in embolized lobes, each 1% flow decrease predicted a volume reduction of 3.4±1.0cm 3 ( P =0.003). 4D flow MRI successfully quantified portal blood flow before and after portal vein embolization in a porcine model. Notably, immediate postembolization changes in portal flow were predictive of lobar volume changes observed at 2 weeks. This porcine model thus provides a valuable platform for investigating the relationship between portal hemodynamics and hypertrophy of the future liver remnant. Furthermore, it will enable systematic evaluation of various embolization agents and techniques, supporting the refinement of interventional strategies in hepatic regenerative research.

Objective: Image quality evaluation in radiology is most relevant when reflects radiologists’ performance. This study assessed how image quality measurement in terms of in vivo -characterized detectability index ( ) for low-contrast liver lesion assessment in CT is correlated with radiologists’ performance across 2 different CT reconstructions. Methods: Fifty-one contrast-enhanced abdominal studies for investigating colorectal liver metastases were prospectively performed using 2 radiation dose exposures and reconstructed with Filtered back projection (FBP) and deep learning image reconstruction (DL) algorithms for a total of 161 noncalcified hypoattenuating lesions for 3 lesion size (D) subsets (&lt;6 mm, 6 to 10 mm, and &gt;10 mm). Images were assessed by expert radiologists for hepatic lesion detection task and likelihood of malignancy across the 2 imaging conditions. All cases were also evaluated automatically in terms of in vivo as a metric of task-based performance, both using a conventional technique and a new formalism of an added frequency term in the internal noise component of to accommodate the nonlinearity of the DL reconstruction ( adj ). Results: The study found conventionally defined d’ well-reflective of radiologists’ evaluation of FBP images but not well-aligned with that of DL images. The new formalism provided more consistent reflection of performance across reconstruction techniques. In particular, in the lesion group D &lt;=6 mm, the difference between radiologists’ accuracy in images acquired with DL and images acquired with FBP was −26%, and the related adj difference was −9%, whereas the was 34%. Analogously, for the lesion group 6 mm &lt; D &lt;=10 mm, the differences were −15%, −13%, and 29%, respectively. Lastly, for the lesion group D&gt;10 mm, radiologists showed the same accuracy in both FPB and DL images, difference in adj was -11%, and difference in was 31%. Conclusion: The new formalism can robustly reflect CT systems clinical performance irrespective of reconstruction algorithm. The methodology can be more readily applied to assess the real-world performance of CT systems.

The purpose of this study was to evaluate the potential clinical value of spectral CT for image guidance during percutaneous thermal ablation, particularly investigating high monoenergetic (MonoE) for metal artifact reduction. A phantom experiment was performed in which an ablation probe was scanned in "continuous CT" (CCT) mode on a spectral CT scanner. ROI measurements quantified metal artifacts for conventional and MonoE CCT images. Subsequently, a retrospective reader study was conducted with 10 patient cases. Three radiologists reviewed cases to select the optimal MonoE setting and perform a Likert score rating (+2: MonoE preferred, -2: conventional preferred). Phantom measurements indicated a reduction in metal artifact for high MonoE (150keV: -46HU) relative to conventional CCT (-122HU). The MonoE setting preference was 151±21keV. The mean Likert score was 1.2±0.7. Radiologists indicated a perceived benefit of high MonoE CCT when probe placement was near a critical structure. This study indicates a clinical preference for high MonoE CCT compared with conventional CCT. Insofar as spectral CCT can be offered at a clinically feasible time frame, our results support the assessment of 150keV image to reduce metal artifact while maintaining satisfactory soft tissue contrast.

To identify risk factors predicting visceral pleural invasion (VPI) in part-solid and solid nodules through meta-analysis, and to develop a predictive model in an independent cohort. The PubMed, Embase, and Web of Science databases were systematically searched to identify studies on pleural-related semantic, nodule semantic, and quantitative computed tomography (CT) features to predict VPI. The pooled odds ratios (ORs) for semantic features and standardized mean differences (SMDs) for quantitative features were calculated to develop a predictive model. A total of 203 patients (147 VPI-negative and 56 VPI-positive) were enrolled in the validation cohort between January and December 2024. The diagnostic performance of the model was assessed using the area under the receiver operating characteristic curve (AUC). Thirteen studies with 3999 patients were included in this meta-analysis. Several key risk factors were identified to construct the predictive model, including pleural indentation (OR: 3.428, 95% CI: 2.559-4.593), nodule type (OR: 4.867, 95% CI: 3.915-6.051), spiculation (OR: 2.581, 95% CI: 1.640-4.062), lobulation (OR: 1.855, 95% CI: 1.148-2.997), vessel convergence sign (OR: 3.606, 95% CI: 1.698-7.656), and the maximum solid diameter (SMD: 0.894, 95% CI: 0.600-1.188). This model yielded an AUC of 0.892 (95% CI: 0.840-0.931) in the validation cohort. This meta-analysis involved the construction of an effective model for predicting VPI by integrating pleural indentation, nodule type, spiculation, lobulation, vessel convergence sign, and maximum solid diameter, which could inform preoperative clinical decision-making for subpleural part-solid and solid nodules.

We aimed to improve preoperative accuracy of tumor staging by evaluating the ability of qualitative and quantitative CT imaging features to predict perirenal fat invasion (PFI) in renal cell carcinoma (RCC). This retrospective case-control study included 86 patients with pathologically proven PFI and 169 controls matched for tumor size without PFI who were treated by nephrectomy between January 2016 and December 2020. Two radiologists independently evaluated the qualitative imaging features of tumor complexity, shape, margin, tumor-fascia contact, perirenal vascularity, fascial thickening, septation, stranding, and nodules. We also compared tumor contact length and protruding distance between the groups. Multivariate logistic regression analyses identified significant predictors of PFI, and diagnostic performance metrics of all predictors were assessed to create a combined model that included all significant predictors. Lobulated shapes and irregular margins were more prevalent in the group with than without PFI ( P <0.05). Perirenal increased vascularity, fascial thickening, septation, stranding, and nodularity were also significantly more prevalent in the PFI group ( P <0.05 for all). Tumor contact length and protruding distance were significantly greater in the PFI group ( P =0.002). Multivariate analysis identified the following independent predictors of PFI: lobulated tumors [odds ratio (OR): 2.03; P =0.042], irregular margin (OR: 3.40; P =0.007), perirenal fascial thickening (OR: 4.20; P <0.001), and contact length >154.2mm (OR: 3.82; P =0.019). The diagnostic performance of these combined predictors was moderate, with 61.6% sensitivity, 79.3% specificity, and 73.3% accuracy. Qualitative CT features (lobulated tumors, irregular margins, perirenal thickened fascia) and an objective quantitative parameter (threshold 154.2mm tumor contact length) were significant independent predictors of perirenal fat invasion in RCC. These findings emphasize the complementary value of combining subjective and objective imaging features to enhance preoperative staging accuracy.

This study aims to clarify the frequency of renal parenchymal defects and deformations in each subtype of perirenal liposarcomas and to compare the differences between well-differentiated and non-well-differentiated types. Patients with perirenal liposarcomas seen between July 2004 and June 2024 were included. Two radiologists blinded to the subtypes retrospectively evaluated CT or MR images for renal parenchymal defects and deformations. Frequencies of these findings were compared between well-differentiated versus non-well-differentiated types using the Fisher test. Forty-two patients (mean age: 66.3±11.5y; 15 men) with perirenal liposarcomas were included. Renal parenchymal defects and deformations were observed in 0 (0%) and 1 (7.7%) of 13 well-differentiated, 5 (29.4%) and 6 (35.3%) of 17 dedifferentiated, 3 (37.5%) and 0 (0%) of 8 myxoid, and 1 (25.0%) and 1 (25.0%) of 4 pleomorphic types, respectively. Non-well-differentiated liposarcomas had higher frequencies of renal parenchymal defects and deformations compared with well-differentiated liposarcomas [9 of 29 (31.0%) vs. 0 of 13 (0%), P =0.038 and 7 of 29 (24.1%) vs. 1 of 13 (7.7%), P =0.398]. Renal parenchymal defects can be occasionally observed (31.0%) in non-well-differentiated perirenal liposarcomas unlike well-differentiated liposarcomas.