Academic Radiology最新文献

Rationale and objectives: To assess interobserver agreement of computed tomography (CT) features in colon cancer, their association with pathological staging, and the influence of baseline characteristics on clinical-pathological agreement.

Materials and methods: CT scans of patients with locally advanced colon cancer treated between 2011 and 2020 at two Dutch hospitals were analyzed. Eleven radiologists independently reviewed the scans in pairs using a structured template. Interobserver agreement was evaluated using Krippendorff's alpha (α) and intraclass correlation coefficients (ICC). Associations between CT features and pathological stages, and the impact of baseline characteristics on clinical-pathological agreement, were assessed using mixed-effects logistic regression.

Results: Interobserver agreement was α = 0.55 (95% CI: 0.51-0.60) for T stage, α = 0.57 (95% CI: 0.52-0.61) for N stage, α = 0.44 (95% CI: 0.36-0.51) for retroperitoneal surgical margin, α = 0.59 (95% CI: 0.52-0.65) for bowel obstruction, α = 0.27 (95% CI: 0.22-0.33) for extramural vascular invasion, α = 0.22 (95% CI: 0.14-0.31) for tumor deposits, ICC = 0.72 (95% CI: 0.70-0.75) for tumor length, and ICC = 0.62 (95% CI: 0.58-0.65) for largest node diameter. Significant associations (P < 0.05) were observed between clinical cT, cN, tumor length, and cEMVI with pT, and between cN, node diameter, and node heterogeneity with pN. Age, tumor location, and differentiation grade significantly influenced agreement.

Conclusion: Several CT features were significantly associated with pathological stage, but their inconsistent interpretation across observers, indicates limited reliability for individualized treatment decisions. Interpretation should therefore focus on features with proven reproducibility, namely tumor length and largest node diameter, applied within standardized protocols, and integrated with the broader clinical and pathological context.

Rationale and objectives: cM0(i+) represents a pre-metastatic stage characterized by the presence of circulating tumor cells (CTCs). Although CTC monitoring could offer valuable prognostic insights, current strategies often lack flexibility, potentially increasing patient burden. Our study aims to investigate whether radiomic could provide a factor associated with cM0(i+) risk in localized renal cell carcinoma (LRCC) patients, which may contribute to risk-adapted monitoring strategies.

Materials and methods: GSE106363, GSE82198, GSE18670 and TCGA-KIRC (n=522) were used to identify CTC-related genes (CRGs) and construct a CTC risk stratification (CRS). Radiogenomic models were trained on CT imaging in TCIA (n=85) to predict the CRS, and its ability to stratify CTC burden and cM0(i+) progression risk was evaluated in our institutional cohort (n=82, median follow-up 192 days) undergoing postoperative CTC assessments by CanPatrol® approximately every three months, following the cM0(i+) criteria: total CTCs ≥6, mesenchymal CTCs ≥1, and a demonstrated trend of progression in either of total or mesenchymal CTCs.

Results: Three genes (CYFIP2, SLC19A1, and ENGASE) were identified as CRGs. The radiogenomic model accurately predicted the CRS [AUC = 0.82 (0.58 ∼ 0.96)] and provided an independent factor of cM0(i+)-free survival [HR = 3.20 (1.50 ∼ 6.85)，1-year AUC = 0.79 (0.65 ∼ 0.92)]. Patients stratified as high-risk by the model exhibited significantly higher epithelial, mixed, and total CTC counts (p < 0.05) and increased risk of cM0(i+) progression (log-rank p < 0.01).

Conclusion: Our study proposes a novel factor derived from contrast-enhanced CT radiomics for stratifying cM0(i+) progression risk in LRCC, which may inform the development of risk-adapted CTC monitoring strategies in future studies.

Rationale and objectives: As the use of magnetic resonance imaging (MRI) continues to grow, it is essential for radiology trainees to develop the confidence and expertise to interpret MRI studies effectively. However, residents have reported inadequate MRI training, often citing limited case volume as a key contributor. This study aims to evaluate the relationship between MRI case volume and confidence in MRI interpretation among diagnostic radiology residents, and to identify factors influencing both case volumes and confidence.

Materials and methods: A retrospective review of MRI case volume between 2018 and 2023 and online survey was performed among current residents and recent graduates of a Canadian diagnostic radiology residency program.

Results: There was a significant strong positive association between current residents' MRI case volume and confidence in MRI interpretation (r = 0.9, P < 0.001, 95% CI 0.7-1.0), and a trend toward a moderate positive correlation among recent graduates (r = 0.4, P = 0.09, 95% CI -0.08-0.7). Participants reported structured MRI rotations, resident proactivity, and staff interest and availability for teaching as key factors influencing resident MRI case volume and confidence in MRI interpretation.

Conclusion: Increased MRI case volumes are associated with greater confidence in MRI interpretation among diagnostic radiology residents. Additional factors, such as dedicated subspeciality MRI rotations, resident initiative, and staff engagement, also play a crucial role.

Rationale and objectives: Previous studies suggest that "drilling" (eyes fixated at one location within a slice while scrolling rapidly between computed tomography (CT) slices) may be more effective than "scanning" (eyes move rapidly to search within each slice while scrolling slowly between slices) for detecting lesions, but evidence has been limited. The purpose of this study is to examine the association between sensitivity and either drilling or scanning for liver metastasis detection.

Materials and methods: Twenty-five radiologists blinded to clinical and previous imaging information marked all suspected hepatic metastases in 40 contrast-enhanced liver CT exams while being monitored by eye-tracking technology. Eye movements were registered to the corresponding liver segment and slice. All livers and proven metastases were demarcated into Couinaud segments. Outcome measures included metastasis detection (sensitivity), interpretation time, average rate of scrolling, and average rate of segment change.

Results: There were 91 metastases, and mean sensitivity was 83%. In univariate analysis, higher reader sensitivity was associated with longer interpretation time (adjusted R² = 0.35, regression coefficient = 5.25, p = 0.002) and smaller segment change rate (i.e., drilling) (adjusted R² = 0.23, regression coefficient = -4.54, p = 0.009). Scrolling rate was not associated with sensitivity (p=0.37). A regression model predicting sensitivity from both interpretation time and segment change rate yielded an adjusted R² of 0.43.

Conclusion: Drilling may outperform scanning in sensitivity for detection of liver metastases when measured as segment change rate, but not as scrolling rate. Longer interpretation time is independently associated with higher sensitivity.

Rationale and objectives: To assess the value of radiomics models and clinical models (CM) based on diverse volumes of interest and clinical indicators in differentiating low Gleason grade group (GGG) from high-GGG in prostate cancer (PCa).

Materials and methods: This study included 312 PCa patients diagnosed pathologically from center 1 and center 2, divided into internal training (dataset A, n=144, center 1), internal validation (dataset B, n=63, center 1) and external test set (dataset C, n=105, center 2). The CM and radiomics models for intratumoral volume (ITV), 2 mm reduction from tumor border (CTV), 2 mm and 4 mm extensions beyond tumor border (PTV2, PTV4), and 4 mm peritumoral transition (PTT) were developed. Model performance was evaluated using area under the curve (AUC), net reclassification improvement (NRI) and integrated discrimination improvement (IDI).

Results: The combined model ITV_PTV4_CM1 demonstrated optimal performance (AUC 0.871 [95% confidence interval: 0.802-0.938] for dataset C), significantly outperformed ITV (0.778 [0.690-0.864]), and PTV4 (0.774 [0.681-0.866]), with all p < 0.05, and also better than CM1 (0.830 [0.753-0.905]). The introduction of ITV+PTV4, PSAD+PSA, and PSA all provide positive gains to model (NRI/IDI > 0, all p < 0). PTT with AUCs of 0.858 and 0.869 for datasets A and B, outperformed other individual radiomics models in center 1. ADC/DWI_gldm emerged as the top-weighted feature.

Conclusion: The ITV_PTV4_CM1 enhances predictive efficacy for preoperative PCa risk stratification. PTV4 and PTT highlight the importance of transition zone features at the peritumoral invasion margin, offering insights into optimal peritumoral extents. The similar efficacy of intratumoral and peritumoral radiomics suggests strategies for optimizing PCa diagnostic workflow.

RATIONALE AND OBJECTIVES: This study aims to determine if half-dose gadoxetic acid-enhanced liver magnetic resonance imaging (MRI) at 5.0 T is feasible by comparing with full-dose MRI at 3.0 T.

Materials and methods: 19 patients with liver disease underwent both full-dose (0.025 mmol/kg) gadoxetic acid-enhanced 3.0-T MRI and half-dose (0.0125 mmol/kg) 5.0-T MRI. Quantitative image quality was assessed by measuring the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and contrast enhancement index (CEI) in liver and hepatic lesions. Qualitative image quality and respiratory motion artifacts were evaluated. Statistical comparisons were performed using paired t-tests or the Wilcoxon signed-rank test.

Results: Half dose 5.0-T MRI yielded significantly higher SNRs in liver and hepatic lesions compared to full-dose 3.0-T MRI (all P < 0.001). The 15-minute hepatobiliary phase (HBP) at 5.0 T achieved image quality comparable to 20-minute HBP at 3.0 T. Specifically, at the 15-minute HBP, the 5.0-T protocol demonstrated significantly higher liver SNR (77.24 ± 12.08 vs. 51.84 ± 8.18 at 20 min for 3.0 T; P < 0.001) and liver-to-lesion CNR (38.93 ± 15.56 vs. 25.37 ± 9.43; P < 0.01). Additionally, respiratory motion artifacts in the early arterial phase were significantly reduced at 5.0 T (1.12 ± 0.33 vs. 1.62 ± 0.86; P < 0.05).

Conclusion: Liver 5.0-T MRI with a half-dose of gadoxetic acid maintains diagnostic image quality while enabling a 25% reduction in HBP acquisition time and mitigating motion artifacts. This technique represents a viable strategy to improve scanning efficiency and patient safety in gadoxetic acid-enhanced liver imaging.