Explore the vast range of titles available.

PurposeEvidence of an association between intravenous contrast media (CM) and persistent renal dysfunction is lacking for patients with pre-existing acute kidney injury (AKI). This study was designed to determine the association between intravenous CM administration and persistent AKI in patients with pre-existing AKI.MethodsA retrospective propensity-weighted and entropy-balanced observational cohort analysis of consecutive hospitalized patients ≥ 18 years old meeting Kidney Disease Improving Global Outcomes (KDIGO) creatinine-based criteria for AKI at time of arrival to one of three emergency departments between 7/1/2017 and 6/30/2021 who did or did not receive intravenous CM. Outcomes included persistent AKI at hospital discharge and initiation of dialysis within 180 days of index encounter.ResultsOur analysis included 14,449 patient encounters, with 12.8% admitted to the intensive care unit (ICU). CM was administered in 18.4% of all encounters. AKI resolved prior to hospital discharge for 69.1%. No association between intravenous CM administration and persistent AKI was observed after unadjusted multivariable logistic regression modeling (OR 1; 95% CI 0.89–1.11), propensity weighting (OR 0.93; 95% CI 0.83–1.05), and entropy balancing (OR 0.94; 95% CI 0.83–1.05). Sub-group analysis in those admitted to the ICU yielded similar results. Initiation of dialysis within 180 days was observed in 5.4% of the cohort. An association between CM administration and increased risk of dialysis within 180 days was not observed.ConclusionAmong patients with pre-existing AKI, contrast administration was not associated with either persistent AKI at hospital discharge or initiation of dialysis within 180 days. Current consensus recommendations for use of intravenous CM in patients with stable renal disease may also be applied to patients with pre-existing AKI.

Kounis Syndrome is a rare allergic reaction that results in coronary vasospasm and may occur in patients with and without coronary artery disease. A 57-year-old man receiving pre-operative vancomycin for osteomyelitis and gangrene of the foot experienced an episode of anginal symptoms associated with transient ischemic 12-lead electrocardiogram (ECG) changes. The patient's symptoms and ECG changes abated with discontinuation of vancomycin and subsequent coronary angiography revealed no evidence of coronary artery disease. Treatment of Kounis Syndrome begins with cessation of the causative agent. Consensus guidelines for the management of Kounis Syndrome have not been established but treatment should both dilate the coronary vessels and suppress the allergic response. Coronary vasospasm after administration of antibiotics, including vancomycin, is a rare but serious reaction. It is important that Emergency Physicians recognize Kounis Syndrome as an uncommon yet dramatic and consequential reaction to such a commonly-administered antibiotic.

This study evaluated segmentation accuracy, efficiency, and radiomic feature stability for manual (MD), artificial intelligence-based (AI), and hybrid (MD + AI) contouring of pelvic organs on planning CT (pCT) and HyperSight cone-beam CT (hCBCT) for adaptive radiotherapy. Dice similarity and 95th percentile Hausdorff distance (HD95) quantified segmentation agreement, while radiomic feature stability was assessed using the concordance correlation coefficient (CCC). Agreement between segmentation approaches was highest for bladder and femora (median Dice 0.95–0.96; HD95 1.88–2.17 mm), intermediate for prostate and rectum (median Dice 0.92; HD95 2.22–2.62 mm), and lowest for seminal vesicles and penile bulb (median Dice 0.76–0.83; HD95 3.01–3.41 mm). AI and MD + AI reduced contouring times by about 90% and 60% compared to MD. Radiomic feature stability differed significantly between segmentation modes (all p adj ≤ 0.05). GLRLM features exhibited significantly higher stability than other features, whereas morphological features showed lower stability. Median radiomic feature stability was highest for bladder and femora, and intermediate for prostate and rectum. In conclusion, AI-based and hybrid contouring achieved high accuracy and substantial time savings, while texture- and intensity-based radiomic features showed robustness with AI segmentation. This study demonstrated feasibility of extracting distinct, reliable quantitative parameters based on AI-only contouring of pelvic structures.

To determine the risk for acute kidney injury (AKI) attributable to intravenous contrast media (CM) administration in septic patients. This was a single-center retrospective propensity matched cohort analysis performed in the emergency department (ED) of an academic medical center. All visits for patients ≥18 years who met sepsis diagnostic criteria and had serum creatinine (SCr) measured both on arrival to the ED and again 48 to 72 h later were included. Of 4171 visits, 1464 patients underwent contrast-enhanced CT (CECT), 976 underwent unenhanced CT and 1731 underwent no CT at all. The primary outcome was incidence of AKI. Logistic regression and between-groups odds ratios with and without propensity-score matching were used to test for an independent association between CM administration and AKI. Incidence of AKI was 7.2%, 9.4% and 9.7% in those who underwent CECT, unenhanced CT and no CT. CM administration was not associated with increased incidence of AKI. Sepsis is a medical emergency proven to benefit from early diagnosis and rapid initiation of treatment, which is often aided by CECT. Our findings argue against withholding CM for fear of precipitating AKI in potentially septic patients.

CT-guided adaptive radiotherapy (aRT) based on HyperSight TM -CBCT provides high-quality imaging, allowing quantitative radiomic feature analysis as a monitoring tool. This study comprehensively evaluates the stability of radiomic features, as potential imaging biomarkers, in pelvic structures of prostate cancer patients treated with adaptive stereotactic body radiation therapy (SBRT). Between December 2023 and July 2024, 32 patients with localized prostate cancer underwent adaptive SBRT at the Ethos ® linear accelerator (Varian, Siemens Healthineers) with HyperSight-CBCT imaging. Longitudinal stability was assessed by intraclass correlation coefficient (ICC) over five fractions of aRT for target structures and non-hollow organs at risk. In pooled organs at risk, 93.0% of features showed very high stability (ICC > 0.9) compared to 67.4% in pooled target structures, indicating significantly lower stability for target structures ( p  = 0.00009129). Second-order features demonstrated greater stability than conventional and shape-based features ( p  = 0.0433, p  = 0.0252). Fraction number significantly affected longitudinal prostate feature variability ( p  = 0.0135). This study comprehensively analyzed HyperSight-CBCT imaging to evaluate longitudinal stability of radiomic features during adaptive SBRT for prostate cancer. The trends observed will provide a framework for future CT-guided aRT studies, facilitating quantitative imaging analysis of radiological biomarkers for clinical translation and improving personalized treatment.

A 62-year-old man presented to the emergency department with acute, atraumatic, swelling of his left ear. Incision and drainage revealed serous fluid without blood or purulence. He was diagnosed with acute perichondritis with an effusion and managed with oral antibiotics. Perichondritis must be recognized and treated promptly to avoid necrosis of the underlying avascular cartilage and auricular deformity.

Background Daily adaptive radiation therapy (ART) of patients with non-small cell lung cancer (NSCLC) lowers organs at risk exposure while maintaining the planning target volume (PTV) coverage. Thus, ART allows an isotoxic approach with increased doses to the PTV that could improve local tumor control. Herein we evaluate daily online ART strategies regarding their impact on relevant dose-volume metrics. Methods Daily cone-beam CTs (1 × n = 28, 1 × n = 29, 11 × n = 30) of 13 stage III NSCLC patients were converted into synthetic CTs (sCTs). Treatment plans (TPs) were created retrospectively on the first-fraction sCTs (sCT 1 ) and subsequently transferred unaltered to the sCTs of the remaining fractions of each patient (sCT 2−n ) (IGRT scenario). Two additional TPs were generated on sCT 2−n : one minimizing the lung-dose while preserving the D 95% (PTV) (isoeffective scenario), the other escalating the D 95% (PTV) with a constant V 20Gy (lung ipsilateral ) (isotoxic scenario). Results Compared to the original TPs predicted dose, the median D 95% (PTV) in the IGRT scenario decreased by 1.6 Gy ± 4.2 Gy while the V 20Gy (lung ipsilateral ) increased in median by 1.1% ± 4.4%. The isoeffective scenario preserved the PTV coverage and reduced the median V 20Gy (lung ipsilateral ) by 3.1% ± 3.6%. Furthermore, the median V 5% (heart) decreased by 2.9% ± 6.4%. With an isotoxic prescription, a median dose-escalation to the gross target volume of 10.0 Gy ± 8.1 Gy without increasing the V 20Gy (lung ipsilateral ) and V 5% (heart) was feasible. Conclusions We demonstrated that even without reducing safety margins, ART can reduce lung-doses, while still reaching adequate target coverage or escalate target doses without increasing ipsilateral lung exposure. Clinical benefits by means of toxicity and local control of both strategies should be evaluated in prospective clinical trials.

Background Cone-beam computed tomography (CBCT)-based adaptive radiotherapy (ART) at the Ethos ® linear accelerator (eLinac) allows for daily anatomical and dosimetric adjustments and relies on robust image quality. This study evaluated the longitudinal image quality of the novel HyperSight TM -CBCT (hCBCT) compared to planning CT (pCT), using phantoms and data of prostate cancer patients undergoing adaptive stereotactic body radiotherapy (SBRT). Building on this, the longitudinal contour sharpness of the organs in fractional hCBCT and their usability for ART workflow across fractions was evaluated. Methods Between December 2023 and May 2024, 26 prostate cancer patients receiving ART at the eLinac with hCBCT technology were enrolled. Phantom studies assessed pCT and hCBCT image quality. Patient based analyses of all 156 imaging scans (pCT and each of the fractional hCBCT) analyzed, longitudinally examined firstly image quality, secondly contour sharpness of prostate, seminal vesicles, and rectal wall, and thirdly confidence to delineate the structures for the ART workflow. Time required for the ART based parameters were recorded. Quantitative metrics included CT number changes in the fat adjacent to the prostate and seminal vesicles. Friedman’s test with Bonferroni correction, Spearman and Intraclass Correlation Coefficient (ICC) were used for statistics. Results hCBCT scans showed robust image quality parameters in the phantom and patient based analysis across fractions. Inter-observer agreement was moderate, with lower rating score for resident compared to the experienced radiation oncologist ( p  < 0.001). Patient based analysis showed no significant differences of the contour sharpness of the prostate and seminal vesicles between pCT and initial hCBCT scan, but contour sharpness ratings declined across treatment fractions. Confidence for the delineation of prostate and seminal vesicles during ART was significantly decreased at later fractions (each p adj <0.05) and this correlated significantly with longer assessment times (p adj ≤0.05). The CT attenuation of the fat tissue adjacent to the prostate and seminal vesicles significantly increased across the fractions (p adj <0.05). Conclusions High-quality imaging for adaptive SBRT in prostate cancer is provided by hCBCT, which offers equivalent tissue visualization compared to pCT. Fraction-dependent decreases in contour sharpness can be detected using longitudinal hCBCT imaging. These decreases are likely related to treatment-induced tissue changes and may impact ART workflow. The rating of the observed effects may potentially be influenced by the observer’s experience.