BACKGROUND AND PURPOSE: Former preterm born males are at higher risk for neurodevelopmental disabilities compared with female infants born at the same gestational age. This retrospective study investigated sex-related differences in the maturity of early myelinating brain regions in infants born <28 weeks’ gestational age using diffusion tensor– and relaxometry-based MR imaging. MATERIALS AND METHODS: Quantitative MR imaging sequence acquisitions were analyzed in a sample of 35 extremely preterm neonates imaged at term-equivalent ages. Quantitative MR imaging metrics (fractional anisotropy; ADC [10⁻³mm²/s]; and T1-/T2-relaxation times [ms]) of the medulla oblongata, pontine tegmentum, midbrain, and the right/left posterior limbs of the internal capsule were determined on diffusion tensor– and multidynamic, multiecho sequence–based imaging data. ANCOVA and a paired t test were used to compare female and male infants and to detect hemispheric developmental asymmetries. RESULTS: Seventeen female (mean gestational age at birth: 26 + 0 [SD, 1 + 4] weeks+days) and 18 male (mean gestational age at birth: 26 + 1 [SD, 1 + 3] weeks+days) infants were enrolled in this study. Significant differences were observed in the T2-relaxation time (P = .014) of the pontine tegmentum, T1-relaxation time (P = .011)/T2-relaxation time (P = .024) of the midbrain, and T1-relaxation time (P = .032) of the left posterior limb of the internal capsule. In both sexes, fractional anisotropy (P [♀] < .001/P [♂] < .001) and ADC (P [♀] = .017/P [♂] = .028) differed significantly between the right and left posterior limbs of the internal capsule. CONCLUSIONS: The combined use of various quantitative MR imaging metrics detects sex-related and interhemispheric differences of WM maturity. The brainstem and the left posterior limb of the internal capsule of male preterm neonates are more immature compared with those of female infants at term-equivalent ages. Sex differences in WM maturation need further attention for the personalization of neonatal brain imaging.

Background: Established clinical risk scores (CRSs) can estimate the prognosis of patients with colorectal liver metastases (CLM) after hepatic resection. However, their ability to predict outcome for patients undergoing neoadjuvant chemotherapy is limited, mainly because most included variables do not reflect a biologic response to neoadjuvant chemotherapy (NAC). This study aimed to evaluate the prognostic value of total metastases volume (TMV) and relative volume reduction (RVR) for patients with CLM undergoing perioperative chemotherapy and surgery. Methods: Liver metastases volume was semi-automatically measured on computed tomography images in 69 patients before and after NAC and compared to established CRS regarding progression-free survival (PFS) and overall survival (OS). Results: Patients with a TMV smaller than 29.5 ml before NAC and 7.5 ml after NAC showed a significantly longer PFS than those with a larger TMV (median, 31.0 vs. 13.7 months [p = 0.005] and 22.6 vs. 9.1 months [p = 0.013], respectively). An RVR after NAC of at least 73% was a positive predictor of PFS (median, 38.0 vs. 9.4 months; p = 0.004) and OS (mean, 59.5 vs. 92.5 months; p = 0.002). Conclusions: Total tumor volume and RVR of CLM seem to be superior to established CRS for patients undergoing neoadjuvant chemotherapy and surgery.

Background: The use of photon-counting detector computed tomography (PCD-CT) has improved image quality in cardiac, pulmonary, and musculoskeletal imaging. Abdominal imaging research, especially about the use of PCD-CT in hepatocellular carcinoma (HCC), is sparse. Objectives: We aimed to compare the image quality of tumors, the liver parenchyma, and the vasculature in patients with HCC using PCD-CT reconstructions at different slice thicknesses and kernels to identify the most appropriate settings for the clinical routine. Methods: CT exams from twenty adult patients with HCC performed with a clinically approved, first-generation PCD-CT scanner (Naeotom Alpha^®, Siemens Healthineers), were retrospectively reviewed. For each patient, images were reconstructed at four different sharp kernels, designed for abdominal imaging (Br40; Br44; Br48; Br56) and at three slice thicknesses (0.4 mm; 1 mm; 3 mm). The reconstruction with the Br40 kernel at 3 mm (Br40_{3 mm}) was used as a clinical reference. Three readers independently assessed the image quality of different anatomical abdominal structures and hypervascular HCC lesions using a five-point Likert scale. In addition, image sharpness was assessed using line-density profiles. Results: Compared with the clinical reference, the Br44_{1 mm} and Br48_{1 mm} reconstructions were rated superior for the assessment of the hepatic vasculature (median difference +0.67 [+0.33 to +1.33], p < 0.001 and +1.00 [+0.67 to +1.67], p < 0.001). Reconstructions for Br40_{1 mm} (+0.33 [−0.67 to +1.00], p < 0.001), and Br44_{3 mm} (+0.0 [0.0 to +1.00], p = 0.030) were scored superior for overall image quality. The noise demonstrated a continuous increase when using sharper kernels and thinner slices than Br40_{3 mm} (p < 0.001), leading to a decrease in contrast-to-noise ratio. Although there was a trend toward increased image sharpness using the slope analysis with higher kernels, this was not significantly different compared with the reference standard. Conclusion: PCD-CT reconstruction Br40_{1 mm} was the most suitable setting for overall image quality, while reconstructions with sharper kernels (Br44_{1 mm} and Br48_{1 mm}) can be considered for the assessment of the hepatic vasculature in patients with HCC.

Background/Objectives: The ultra-high-resolution (UHR) mode of photon-counting detector computed tomography (PCD-CT) is the most dose-intensive series of a multiphase pancreatic protocol in relation to its scan length, and the pancreas cannot be localised on a topogram. We assessed whether an ultra-low-dose (ULD) unenhanced planning series reduces its scan range and dose without compromising complete depiction of the pancreas. Methods: In this prospective single-centre study, 61 pancreatic protocol examinations in 56 patients were performed on a first-generation dual-source PCD-CT. Following a protocol change, the UHR scan range was planned from the topogram in group A (n = 30) and from a ULD unenhanced series in group B (n = 31). Dose indices, scan length, margins to the pancreas and completeness of depiction were recorded. Results: The UHR scan range was 27% shorter in group B (114 vs. 160 mm; p < 0.001), driven by the cranial margin (−58%; p < 0.001) rather than the caudal margin (p = 0.076). Neither the volume CT dose index nor the size-specific dose estimate of the UHR series differed (p = 0.74 and p = 0.35), yet its dose–length product fell by 25% (p = 0.003) and its share of the dose excluding the mandatory venous phase fell from 62.0% to 50.7% (p < 0.001). The total dose was 7.5% lower without reaching significance (p = 0.37). Incomplete depiction occurred in 5 of 30 vs. 5 of 31 examinations (p = 1.00). The body habitus was closely matched. Conclusions: A ULD planning series was associated with a more tightly targeted UHR pancreatic phase, with a 27% shorter scan range and a 25% lower dose–length product for that series, and with no detected increase in incomplete depiction of the pancreas. With topogram-based planning alone, over-scanning was most pronounced at the cranial border. The reduction was confined to the ultra-high-resolution series and was statistically significant there; the total examination dose was lower with ultra-low-dose planning, but this difference was not statistically significant and no conclusion about total dose should be drawn from it.

Proposing three-dimensional morphological criteria to measure tumor burden in colorectal liver metastases: Total metastases volume and relative volume reduction represent valuable prognostic parameters for patients undergoing neoadjuvant chemotherapy and surgery (

Background/Objectives: Pleura-based pulmonary nodules in soft-tissue sarcoma (STS) patients remain diagnostically challenging, and entity-specific contrast-enhanced ultrasound (CEUS) data are scarce. We aimed to characterize CEUS perfusion patterns of pleura-based STS pulmonary metastases in a pilot cohort. Methods: We investigated a single-center retrospective cohort at a tertiary STS referral center (Dec 2024–Dec 2025). Of 51 consecutive STS patients with suspected pulmonary metastases screened, 32 lacked pleural contact and 6 were excluded for logistical reasons; the remaining 13 underwent standardized CEUS of a pleura-contacting lesion (≥5 mm) visible on B-mode lung ultrasound (B-LUS), with 1 excluded on biopsy (anaplastic lymphoma). The reference standard combined histology, therapy-related size reduction of the index lesion, and/or documented distant metastatic STS. Two readers rated all examinations independently, with adjudication by a third senior reader. Wilson 95% confidence intervals (CIs) and Cohen’s κ were computed. Results: In the 12 analyzed patients (mean age 58.8 ± 17.8 years; 7 male), the index lesion was histologically confirmed in 4 (33.3%). On CEUS, bronchial-arterial (BA) enhancement predominated (10/12; 83.3%, 95% CI 55.2–95.3%) and pulmonary-arterial timing occurred in 2/12 (16.7%). Marked enhancement was present in 9/12 (75.0%), homogeneous in 8/12 (66.7%), and rapid washout (<120 s) in all lesions (12/12; 100%, 95% CI 75.8–100%). Inter-reader agreement was substantial to almost perfect for the diagnostically relevant CEUS perfusion variables (enhancement κ = 0.75; EE κ = 0.80; HE κ = 0.82) and moderate for the descriptive shape variable (Form κ = 0.47). Conclusions: In this selected pilot cohort, pleura-based STS lung metastases most commonly showed BA-dominant enhancement with universal rapid washout. The findings are hypothesis-generating and require validation in larger, prospective multicenter cohorts.