Purposes: The purpose of this study was to explore the diagnostic performance of Cho peak area (Cho Are), Cho peak amplitude (Cho Amp), and the combined approach (Cho Are_Amp) in detecting rabbit VX2 liver cancer at the early stage via hydrogen-1 proton magnetic resonance spectroscopy (¹H-MRS), as well as the correlations between Cho Are, Cho Amp, and tumor parameters like diameter and volume.Methods: Conventional magnetic resonance imaging (MRI) and MRS were performed to scan the VX2 liver cancer in rabbit. The tumor diameter was measured on T2-weighted imaging (T2WI), and the tumor volume was accordingly calculated. Cho Are and Cho Amp were obtained from MRS. The diagnostic performance of Cho Are, Cho Amp, and Cho Are_Amp was assessed by a receiver operating characteristic (ROC) curve and area under ROC curve (AUC), whereas specificity and sensitivity were calculated by the maximum Youden’s index. Spearman’s correlation analysis was performed to evaluate the relevance between tumor parameters (diameter, volume) and radiological indexes (Cho Are, Cho Amp).Results: ROC curve analysis showed that Cho Amp, Cho Are, and Cho Are_Amp were effective in diagnosing VX2 liver cancer. The AUC of Cho Amp was 0.883, and the specificity and sensitivity were 0.944 and 0.722, respectively (p < 0.001). The AUC of Cho Are was 0.807, and the specificity and sensitivity were 0.778 and 0.833, respectively (p < 0.05). The AUC of Cho Are_Amp was 0.892, and the specificity and sensitivity were 0.833 and 0.833, respectively (p < 0.001). Cho Are and Cho Amp exhibited a high positive correlation with tumor diameter and tumor volume, among which Cho Amp demonstrated better correlations to tumor diameter and tumor volume (r = 0.956 and 0.946) than that of Cho Are (r = 0.787 and 0.794). A high positive correlation was detected between Cho Are and Cho Amp (r = 0.787), as well as tumor diameter and tumor volume (r = 0.965).Conclusion: Cho Are_Amp can be used as an effective tool in diagnosing early-stage VX2 liver cancer with satisfied diagnostic accuracy. Cho Are and Cho Amp were positively correlated with tumor volume and tumor diameter. The results of this study provide further evidence that Cho Amp and Cho Are_Amp of MRS could aid in the early diagnosis of liver cancer.

All the previous subtraction coronary CT angiography (CCTA) had strict heart rate (HR) inclusion criteria. In this study, a new subtraction method was applied to patients with various HR. The post-contrast scan time was respectively 3.5 s after ascending aorta peak enhancement while HR >80 bpm, 4 s while 65≤ HR ≤80 bpm and 4.5 s while HR <65 bpm. Forty-six patients who underwent the new subtraction protocol were enrolled and patients were stratified into the high HR group (≥70 bpm) and low HR group (50%) were compared between the conventional CCTA and subtraction CCTA and between the high HR group and low HR group, respectively. All enrolled patients got sufficient coronary artery enhancement. In patients with ICA performed, receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) for the diagnosis of significant stenosis was 0.93 in subtraction CCTA and 0.73 in conventional CCTA (p < 0.05). Furthermore, there were no significant differences in image quality improvement, specificity, positive predictive value and accuracy between the high HR group and low HR group. The new subtraction CCTA method broadened the clinical availability for patients with high HR.

Objectives: The BRAF^V600E is the most common oncogene in thyroid cancer and is associated with the aggressiveness of papillary thyroid carcinoma (PTC). The aim of this study was to investigate the effectiveness of the arterial enhancement fraction (AEF) and dual-layer detector spectral computed tomography (DLCT) parameters for predicting the BRAF^V600E mutation in PTC. Methods: A total of 237 patients with PTC who underwent DLCT and BRAF^V600E mutation detection (mutant group: n = 187; wild group: n = 50) were retrospectively reviewed. The receiver operating characteristic curves evaluated the effectiveness of the prediction models based on the significantly different variables using logistic regression analysis. The nomogram of the prediction model with the highest AUC in the validation cohort was constructed. Results: The AUCs of the DLCT+ Hashimoto’s thyroiditis (HT) and AEF + DLCT + HT prediction models were 0.901 and 0.896, respectively, in the training cohort and 0.801 and 0.853 in the validation cohort. The calibration curve revealed the good agreement between the prediction results and the actual observations using the AEF + DLCT + HT model. The DCA demonstrated that the model can provide net benefit for all threshold probabilities. Conclusions: As an effective and visually noninvasive prediction tool, the AEF + DLCT + HT-based nomogram presented satisfactory effectiveness in preoperatively predicting the BRAF^V600E mutation in PTC.

Background/Objectives: Accurately distinguishing malignancy in thyroid micronodules (≤10 mm) is crucial for clinical management, yet it is challenging due to the limitations of conventional ultrasonography-guided biopsy. This study aims to evaluate the predictive value of dual-layer spectral computed tomography (DSCT)-derived arterial enhancement fraction (AEF) in diagnosing thyroid microcarcinomas. Methods: In the study, 321 pathologically confirmed thyroid micronodules (benign = 131, malignant = 190) from Chongqing General Hospital underwent preoperative DSCT. Quantitative parameters of DSCT, including the normalized iodine concentration (NIC), normalized effective atomic number (NZ_eff), and slope of the spectral Hounsfield unit curve (λHU_(40–100)), were assessed. Both single-energy CT (SECT)-derived AEF (AEF_S) and DSCT-derived AEF (AEF_D) were calculated. Conventional image features included microcalcifications and enhancement blurring. Correlation between AEF_D and AEF_S was determined using Spearman’s correlation coefficient. Diagnostic performance was evaluated by calculating the area under the curve (AUC) using receiver operating characteristic (ROC) analysis. Results: Malignant micronodules exhibited significantly lower AEF_D (0.958 vs. 1.259, p < 0.001) and AEF_S (0.964 vs. 1.436, p < 0.001) versus benign nodules. Arterial phase parameters—APλHU_(40–100), APNIC, APNZ_eff—differed significantly between groups (all p < 0.001), whereas venous phase parameters (VPλHU_(40–100), VPNIC, VPNZ_eff) showed no differences (all p > 0.05). Multivariate analysis revealed that λHU_(40–100) as an independent predictor of malignancy, with an odds ratio (OR) of 0.600 (95% confidence interval (CI): 0.437–0.823; p = 0.002) and an AUC of 0.752 (95% CI: 0.698–0.806). A significant positive correlation was identified between AEF_D and AEF_S (r = 0.710; p < 0.001). For diagnosing malignancy, AEF_D demonstrated superior overall performance (AUC: 0.794; sensitivity: 70.5%; specificity: 81.7%; accuracy: 75.1%) to AEF_S (0.753; 71.1%; 74.0%; 72.3%), APλHU_(40–100) (0.752; 68.9%; 75.6%; 71.7%), and calcification (0.573; 21.6%; 92.4%; 50.5%). Clinically, AEF_D reduced the unnecessary biopsy rate to 18.3%, preventing 107 procedures in our cohort. Conclusions: AEF_D and AEF_S demonstrated strong correlation and comparable diagnostic performance in the evaluation of thyroid micronodules. Furthermore, AEF_D showed favorable diagnostic efficacy compared to both spectral parameters and conventional imaging feature. More importantly, the application of AEF_D significantly reduced unnecessary biopsy rates, highlighting its clinical value in optimizing patient management.

Background: Ductal communication is a critical discriminator for differentiating intraductal papillary mucinous neoplasms (IPMNs) from other pancreatic cystic neoplasms. This study evaluated dual-layer spectral detector computed tomography (DLCT)-derived virtual monoenergetic images (VMIs) for displaying IPMN-duct communication compared to conventional polyenergetic images (PEIs) and magnetic resonance cholangiopancreatography (MRCP). Methods: A total of 35 patients with IPMNs from August 2021 to September 2023 were enrolled in this cross-sectional study. PEIs and VMIs (40/50/60/70 keV) were reconstructed at arterial phase (AP) and portal venous phase (PVP). Quantitative metrics [attenuation difference (AD), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR)] for pancreatic parenchyma, lesions, and ducts were measured. Two radiologists independently assessed qualitative parameters (5-point Likert scales) and duct communication. Statistical analyses included analysis of variance (ANOVA) test, Friedman test, inter-reader agreement (kappa), and McNemar’s test. Results: Quantitative analysis demonstrated that VMI 40 keV achieved the highest AD, SNR, and CNR for lesions/ducts (P130% [224.1 vs. 94.8 Hounsfield units (HU); P<0.001]. VMI 40–50 keV provided significantly higher AD and CNR than VMI 60–70 keV (P<0.01). Qualitatively, VMI 40 keV scored optimally (median =5 across all parameters; P<0.001 vs. PEI) with excellent inter-reader agreement (κ=0.78–0.81). DLCT at VMI 40 keV displayed ductal communication in all 30 patients (100%), whereas MRCP demonstrated 28/30 cases (93.3%, P=0.500). Conclusions: VMI 40–50 keV significantly improved quantitative and qualitative image quality in the display of IPMN-duct communication over PEI and higher-keV VMIs, achieving diagnostic equivalence to MRCP. This supports DLCT as a practical alternative when MRCP is contraindicated or unavailable.

Dual-layer detector spectral computed tomography (DLCT) and fine-needle aspiration (FNA) are commonly used in papillary thyroid carcinoma (PTC). However, whether FNA affects DLCT quantitative parameters remains uncertain. This study aimed to investigate the effect of FNA on DLCT parameters in PTC and to determine the optimal timing for DLCT examination. This retrospective study included 689 patients with PTC, who were categorized into pre-FNA (n = 222) and post-FNA (n = 467) groups according to the sequence of FNA and DLCT. Propensity score matching (PSM) was applied to balance confounding variables. Sensitivity analyses were performed using inverse probability of treatment weighting and multivariate regression. DLCT parameters, including virtual monoenergetic images (VMIs) at 40, 70, and 100 keV; spectral attenuation curve slope (λ_HU); iodine concentration (IC); normalized IC (NIC); effective atomic number (Z_eff); and normalized Zeff (NZ_eff), were compared between groups in arterial (AP) and venous phases (VP). Post-FNA time intervals were ranked and divided into deciles. For each DLCT parameter, standardized differences from the pre-FNA baseline were plotted across deciles to propose temporal cutoffs, which were validated by comparing post-FNA subgroups with the pre-FNA group. Covariates were well balanced after PSM, with all standardized mean differences below 0.25. Sensitivity analyses confirmed consistent direction of effect estimates across methods. Two clinically relevant exploratory temporal landmarks were observed around 6 and 18 days. Within 6 days after FNA, significant differences were observed in AP VMIs (40, 70, 100 keV), λHU, IC, NIC, and VP VMI at 100 keV. Between 7 and 18 days, only VP-IC remained significantly altered. Beyond 18 days, no parameters differed from pre-FNA baselines. DLCT parameters showed a dynamic post-FNA temporal pattern, with early and later candidate recovery windows centered around approximately 6 and 18 days. From a clinical perspective, DLCT may be considered before FNA or after about 6 days, whereas a later interval around 18 days may be preferable when minimizing biopsy-related perturbation is particularly important.