European Radiology最新文献

Many reports on adverse effects related to positive gastrointestinal (GI) contrast media (CM) predate 2000; therefore, a literature review on their current safety profile was warranted. This article reviews the literature and updates the Contrast Media Safety Committee guidelines of the European Society of Urogenital Radiology on the safety of positive GI iodine-based and barium sulphate-based CM. A systematic literature search (2000-2025) identified 2 randomised controlled trials, 2 comparative studies, 17 reviews, and 29 case reports on the adverse effects of positive GI CM. Enteric non-ionic iodine-based low- and iso-osmolar CM are more palatable than ionic hyperosmolar agents (HOCM) and are preferred for oral use. The most frequent adverse effects of enteric ionic iodine-based HOCM are nausea, diarrhoea, vomiting, abdominal pain, and unpleasant taste, while pulmonary complications following aspiration are extremely rare. Hypersensitivity reactions due to limited (1-2%) systemic absorption of iodine-based CM are very uncommon; however, patients with a history of such reactions should be managed as for intravascular iodine-based CM administration. For barium sulphate CM, nausea, vomiting, and constipation are the most reported adverse effects. Minor leakage into the mediastinum or aspiration of small amounts into the lungs is rarely life-threatening. In contrast, intraperitoneal leakage can trigger inflammatory reactions, granuloma formation, and intestinal adhesions. If bowel perforation is suspected, fluoroscopic examination with iodine-based CM should precede barium administration. Hypersensitivity may occur due to excipients within barium preparations rather than barium itself. KEY POINTS: Question What are the current safety issues associated with positive GI radiological CM? Finding Nausea and vomiting are the most commonly reported adverse effects of positive enteric CM. Many reports of other adverse effects date back to before 2000. Clinical relevance The use of positive GI CM has diminished in recent decades. However, these CM have excellent safety profiles and are safer than traditionally assumed.

Objective: To investigate the clinical value of Doppler ultrasound in the rapid evaluation of therapeutic efficacy of angioplasty and prediction of recurrence in patients with Budd-Chiari syndrome (BCS).

Materials and methods: A retrospective study was conducted on BCS patients who underwent angioplasty at our hospital between January 2015 and December 2024. Ultrasound examinations were performed preoperatively and within 7 days postoperatively to compare changes in ultrasound parameters. Follow-up ultrasounds were conducted postoperatively. Differences in ultrasound parameters between recurrence and non-recurrence groups were analyzed to identify indicators for the rapid evaluation of recurrence. Cox regression analysis was used to identify independent risk factors for recurrence.

Results: A total of 99 patients (51 males, 48 females; mean age 39.38 ± 12.20 years) were included. Postoperative ultrasound showed significant increases in portal vein (PV) diameter (p = 0.019) and velocity (p < 0.001), while caudate lobe thickness (p = 0.016), spleen length (p = 0.004), spleen thickness (p = 0.012), and ascites depth (p < 0.001) decreased. During follow-up, PV velocity slightly decreased in the non-recurrence group (25.1 cm/s vs 28.3 cm/s, p = 0.018), while it significantly declined in the recurrence group (21.4 cm/s vs 30.2 cm/s, p < 0.001). The median velocity decline was greater in the recurrence group (-7 cm/s vs -1 cm/s, p = 0.003). Multivariate Cox regression identified postoperative paraumbilical vein dilation (HR: 2.970, 95% CI: 1.232-7.156, p = 0.015) and preoperative high D-dimer levels (HR: 1.258, 95% CI: 1.079-1.466, p = 0.003) as independent risk factors for recurrence.

Conclusion: Doppler ultrasound is a valuable tool for the rapid evaluation of hepatic drainage during follow-up, particularly through monitoring PV velocity. Postoperative paraumbilical vein dilation may serve as a predictive marker for future recurrence.

Key points: Question Evaluating angioplasty efficacy in BCS is complex and time-consuming, while predicting recurrence with Doppler ultrasound is challenging. Findings During follow-up, ultrasound monitoring of portal vein flow velocity reflects hepatic drainage, while postoperative paraumbilical vein dilation was an independent risk factor for recurrence. Clinical relevance Doppler ultrasound allowed for rapid evaluation of postoperative hepatic drainage in BCS patients during follow-up, optimizes examination protocols, predicts future vascular recurrence, and establishes a foundation for individualized follow-up and treatment.

Objectives: To validate a previously published CT-based severity score of ischemic colitis and to propose a potential improvement by assessing severity using clinical, biological, and CT criteria.

Materials and methods: This retrospective single-center study included 174 patients (mean age, 73 ± 12 years; 85 men) with ischemic colitis diagnosed between 2014 and 2023. All underwent contrast-enhanced CT. Severe ischemic colitis was defined by death within 1 month, necrosis at colonoscopy, surgery, or superior mesenteric artery stenting. Clinical, biological, and CT features were compared between severe and non-severe cases. The Montpellier CT severity score was applied to the cohort. Logistic regression was used to test additional CT predictors and to propose a modified score.

Results: Among 174 patients, 97 (56%) had non-severe and 77 (44%) had severe ischemic colitis. The Montpellier score showed 68% sensitivity, 81% specificity, and an AUC of 0.78 (95% CI: 0.71-0.85). Multivariate analysis identified decreased wall enhancement, right colon involvement, and peritoneal effusion as additional severity predictors. A modified score including decreased wall enhancement achieved 71% sensitivity, 80% specificity, and an AUC of 0.80 (95% CI: 0.73-0.86).

Conclusion: CT-based severity scoring was useful in predicting severe ischemic colitis. Montpellier score and modified Montpellier score (adding the decreased wall enhancement criterion) appeared to be reliable tools in practice.

Key points: Question Severe ischemic colitis remains difficult to diagnose, and CT imaging provides objective criteria to differentiate between mild and life-threatening forms. Findings A validated CT-based severity score accurately stratifies patients and improves diagnostic performance in clinical practice. Clinical relevance CT-based severity scoring helps identify patients with ischemic colitis who are at high risk of adverse outcomes, supporting timely surgical decision-making and improving clinical management.

Objectives: Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) is a marker of hemodynamic impairment linked to poor outcomes. However, its underlying vascular pathology remains unclear. We aimed to evaluate the relationships between FVH, infarction, and vascular lesion burden, and explore whether infarction and vascular lesion burden can discriminate FVH presence and burden.

Materials and methods: A total of 253 consecutive patients with middle cerebral artery lesions who underwent vessel wall imaging were retrospectively enrolled. Multivariate logistic regressions were performed to identify discriminatory factors for FVH presence or burden; area under the curve (AUC), sensitivity and specificity assessed the discriminatory ability of combined models.

Results: Infarction, severe stenosis, and vascular wall marked enhancement were independently associated with FVH (ORs 2.995, 4.074, 2.141; all p < 0.05). Infarction, severe stenosis, max wall thickness, and max vascular lesion length were independently correlated with higher FVH burden (ORs 2.966, 8.785, 2.344, 1.049; all p < 0.05). The combined model (infarction + severe stenosis + marked enhancement) discriminated FVH presence with an excellent AUC of 0.803 (95% CI: 0.749-0.850, p < 0.001; sensitivity 76.6%; specificity 76.7%). The combined model (infarction + severe stenosis + max wall thickness + max vascular lesion length) discriminated higher FVH burden with an AUC of 0.801 (95% CI: 0.746-0.848, p < 0.001; sensitivity 80.8%; specificity 70.9%).

Conclusion: Infarction and vascular lesion burden are key factors associated with FVH. Our findings suggest a pathophysiological link between FVH and underlying vessel wall pathology, positioning FVH as a potential integrative MRI biomarker.

Key points: Question While FLAIR vascular hyperintensity (FVH) indicates hemodynamic compromise and slow collateral flow, how the underlying vascular lesion burden contributes to FVH formation remains unclear. Findings Infarction, severe stenosis, and vascular lesion burden features effectively distinguished both FVH presence and higher burden, with combined models demonstrating excellent discriminatory performance. Clinical relevance FVH may serve as a valuable and readily accessible biomarker on conventional MRI that integrates infarction and specific vascular characteristics, suggesting its potential to enhance risk stratification and guide personalized therapeutic decisions in clinical practice.

Objectives: We investigated whether metabolic ratios derived from ultra-high-field 7-T 3D-FID-CRT-MRSI can predict intraoperatively visible 5-aminolevulinic acid (5-ALA) fluorescence in gliomas and compared their predictive performance to established imaging markers, including contrast enhancement (CE) on MRI and PET tumor-to-normal ratio (TNR).

Materials and methods: We retrospectively analyzed 43 patients with histopathologically confirmed adult-type diffuse gliomas (CNS WHO grades 2-4) who underwent preoperative 7-T MRSI and 5-ALA-guided resection. Group differences between 5-ALA-positive and 5-ALA-negative tumors were tested for 16 metabolic ratios to either total creatine (tCr) or combined N-acetylaspartate and N-acetyl-aspartyl-glutamate (NAA + NAAG; total NAA; tNAA) using non-parametric statistics with Šidák correction. CE-MRI status and PET TNR (subcohort, n = 31) were included as reference predictors. We additionally evaluated a subgroup of non-enhancing gliomas (n = 27). Receiver operating characteristic (ROC) analysis was performed to determine diagnostic performance.

Results: 5-ALA-positive gliomas demonstrated significantly altered metabolic profiles, showing lower mI/tNAA (p < 0.001) and higher Gln/tCr, Glx/tCr, Gly/tCr, and GSH/tCr ratios (all p < 0.001). These ratios achieved high predictive accuracy for fluorescence (AUC_range = 0.79-0.94), comparable or superior to PET TNR (AUC = 0.90) and CE-MRI (AUC = 0.84). In a subcohort of nonenhancing gliomas, Gly/tCr and Gln/tCr showed a high prediction accuracy (AUC = 0.90).

Conclusion: 7-T MRSI metabolic ratios can predict intraoperative 5-ALA fluorescence and may serve as an alternative or adjunct to CE-MRI and PET for preoperative patient selection for 5-ALA administration. Finally, these findings could be especially beneficial in non-enhancing gliomas, where CE-MRI offers limited predictive information.

Key points: Question Does 7-T MRSI enable preoperative prediction of 5-ALA fluorescence to support patient selection for fluorescence-guided glioma surgery? Findings Several 7-T MRSI metabolic ratios (mI/tNAA, Gln/tCr, Glx/tCr, Gly/tCr and GSH/tCr) robustly predicted 5-ALA fluorescence across glioma subtypes, with diagnostic performance comparable to contrast-enhanced MRI and PET. Clinical relevance Ultra-high-field 7-T MRSI enables noninvasive preoperative prediction of intraoperative 5-ALA fluorescence in gliomas with performance comparable to PET and contrast-enhanced MRI, supporting surgical planning without the need for contrast agents or radiation exposure.

Objectives: To investigate MRI-based breast edema patterns as biomarkers of tumor aggressiveness and their predictive value for pathological response to neoadjuvant chemotherapy (NAC) in invasive breast cancer.

Materials and methods: This retrospective study evaluated 235 female patients (mean age, 52 ± 12 years) with biopsy-proven invasive breast cancer who underwent pre-NAC breast MRI. After excluding 19 patients (10 for inadequate image quality, 9 for post-biopsy imaging), 216 patients were analyzed. Breast edema score (BES) was independently assessed by two radiology residents to evaluate interobserver agreement. Subsequently, a breast radiologist reviewed all cases to establish the definitive dataset. The differences in clinicopathological characteristics between the two groups and between different BES were compared.

Results: Interobserver agreement for BES classification was very high (92.6% concordance). Edema presence correlated significantly with larger tumor size (p = 0.001), higher histological grade (p = 0.001), axillary lymph node metastasis (p = 0.015), hormone receptor negativity (p < 0.001), lymphovascular invasion (p = 0.031), and elevated Ki-67 (p = 0.001). Higher BES groups (BES 2-4) showed stronger associations with aggressive features: tumor size (p < 0.001), grade (p = 0.022), hormone receptor negativity (p = 0.001), non-luminal subtypes (p = 0.001), and intratumoral necrosis (p = 0.002). Neither edema nor BES predicted pathological response to NAC (p = 0.999, p = 0.299).

Conclusion: BES and edema are robust imaging biomarkers of tumor aggressiveness but demonstrate no predictive value for NAC response. MRI-based edema scoring holds clinical relevance for noninvasive tumor phenotyping and risk stratification in breast cancer management.

Key points: Question Can MRI-based breast edema patterns predict tumor aggressiveness and pathological response to neoadjuvant chemotherapy in invasive breast cancer patients, aiding noninvasive risk stratification? Findings BES correlates with aggressive tumor features (larger size, higher grade, hormone negativity; all p < 0.050 but shows no predictive value for NAC response (p = 0.299). Clinical relevance BES serves as a practical imaging biomarker for risk stratification and tumor phenotyping, guiding individualized therapy. However, it shows no utility in predicting NAC response, emphasizing the need for complementary predictive tools in treatment planning.

Objective: Neoplastic portal vein thrombosis (PVT) is a critical prognostic factor in hepatocellular carcinoma (HCC); however, differentiation from bland PVT remains challenging using conventional imaging criteria. Photon-counting detector CT (PCD-CT) enables quantitative iodine density (ID) assessment in every contrast-enhanced acquisition. This study evaluated the diagnostic performance of ID for distinguishing bland from neoplastic PVT.

Materials and methods: In this retrospective single-center study, 104 patients with suspected PVT who underwent PCD-CT between 09/2022 and 08/2024 were included. Based on imaging, follow-up data, and multidisciplinary consensus, patients were classified into four groups: HCC with neoplastic PVT (n = 18), HCC with bland PVT (n = 29), bland PVT without malignancy (n = 31), and neoplastic PVT in non-HCC malignancies (n = 26). ID was measured in the late arterial phase (LAP) and portal venous phase (PVP) by two independent radiologists and compared with a CT feature-based score including vessel infiltration, thrombus extension, and arterial hyperenhancement.

Results: ID measurements demonstrated excellent inter- and intra-rater agreement (ICC ≥ 0.99). ID was significantly higher in neoplastic PVT in both phases. Diagnostic performance was high, with sensitivities and specificities of 100% and 95.9% in LAP and 93.1% and 100% in PVP (AUC 0.98 (95% CI: 0.95-1.00) and 0.97 (95% CI: 0.92-1.00)). The feature-based score showed lower accuracy. In non-HCC malignancies, ID achieved high diagnostic accuracy in PVP.

Conclusion: ID derived from PCD-CT reliably differentiates neoplastic from bland PVT in HCC and outperforms conventional CT features. In non-HCC malignancies, ID is particularly accurate in the portal venous phase, supporting its broader clinical utility as an imaging biomarker in this contrast media phase.

Key points: Question Can iodine density measured by photon-counting detector CT improve the differentiation between bland and neoplastic portal vein thrombosis? Findings Iodine density measurements obtained with photon-counting CT accurately differentiated neoplastic from bland portal vein thrombosis and outperformed established morphologic CT features. Clinical relevance Photon-counting CT-derived iodine density enables reliable, noninvasive identification of neoplastic portal vein thrombosis, thereby improving diagnostic confidence and treatment planning in patients with hepatocellular carcinoma and other malignancies.

Objectives: To propose and validate a personalized iodine delivery rate (IDR) based injection protocol for coronary CT angiography (cCTA) on photon-counting CT.

Materials and methods: First, ideal IDR (IDR_IDEAL) was retrospectively calculated for a HU target of 500 in 55 keV image reconstructions. Next, linear regression analysis was performed with IDR_IDEAL and demographic parameters to derive a candidate IDR formula. This was implemented in two validation groups characterized by injection rate (3.5 and 5.0 mL/s). Here, coronary enhancement was quantified and equivalence assessed for a predefined HU range (500 ± 50). Additionally, a reader study assessed perceived enhancement of the coronary tree.

Results: This IRB-approved study used a retrospective cohort of 162 patients (group A: 58 ± 12 years; 81 men) and two prospective cohorts of 51 patients (group B1: 60 ± 13 years; 22 men and group B2: 59 ± 12 years; 30 men). IDR_IDEAL correlated best with fat-free mass (FFM) (r = 0.67) and was integrated for contrast personalization. Prospectively, mean coronary enhancement was 533 ± 97 HU and 528 ± 68 HU for both groups (p = 0.79) with mean IDR values of 1.01 ± 0.11 gI/s and 1.07 ± 0.14 gI/s. However, distribution variances were significantly different (p = 0.015). Subjective scoring showed no differences between the two groups on overall and per-vessel level (p > 0.05).

Conclusion: A personalized, IDR-based injection protocol for cCTA was proposed and validated. FFM was best for IDR_IDEAL prediction. Higher injection rates provided more precise coronary enhancement.

Key points: Question Virtual mono-energetic images lead to low iodine delivery rate settings, but the impact on coronary enhancement is not clear. Findings An iodine delivery rate-based injection protocol implementing personalized contrast volume dilutions with set injection duration and high injection rate improved coronary enhancement. Clinical relevance Iodine delivery rate fine-tuning is a promising approach for coronary CT angiography with low iodine volumes. High injection rates provide more accurate and precise coronary enhancement.