The aim of this study is to fabricate biodegradable PLA-based composite filaments for 3D printing to manufacture bear-loading lattice structures. First, CaCO₃ and TCP as inorganic fillers were incorporated into a PLA matrix to fabricate a series of composite filaments. The material compositions, mechanical properties, and rheology behavior of the PLA/CaCO₃ and PLA/TCP filaments were evaluated. Then, two lattice structures, cubic and Triply Periodic Minimal Surfaces-Diamond (TPMS-D), were geometrically designed and 3D-printed into fine samples. The axial compression results indicated that the addition of CaCO₃ and TCP effectively enhances the compressive modulus and strength of lattice structures. In particular, the TPMS-D structure showed superior load-carrying capacity and specific energy absorption compared to those of its cubic counterparts. Furthermore, the deformation behavior of these two lattice structures was examined by image recording during compression and computed tomography (CT) scanning of samples after compression. It was observed that pore structure could be well held in TPMS-D, while that in cubic structure was destroyed due to the fracture of vertical struts. Therefore, this paper highlights promising 3D-printed biodegradable lattice structures with excellent energy-absorption capacity and high structural stability.

Objectives: Preoperative differentiation of muscle-invasive bladder cancer (MIBC) is challenging. This study explores the application of the Dual-Energy CT (DECT) model and the vesical imaging reporting and data system (VI-RADS) in assessing MIBC and compares their diagnostic performance. Materials and methods: This single-center prospective study included 105 patients (33 MIBC and 72 non-MIBC cases). Two radiologists independently performed DECT morphological assessment, and evaluated quantitative DECT parameters and VI-RADS scores, blinded to the pathological findings. A DECT-based model was constructed by integrating independent quantitative predictors with tumor diameter ( D ). Diagnostic performance was compared using the area under the receiver operating characteristic curve (AUC). Subgroup analyses were performed for equivocal VI-RADS 3–4 cases and small lesions ( D < 3 cm). Results: VI-RADS achieved an AUC of 0.926 (sensitivity 0.970) but low specificity (0.542). The DECT model showed moderate performance (AUC = 0.761). However, the DECT + D model achieved an AUC of 0.925, comparable to VI-RADS ( p > 0.05), with improved specificity (0.833). Crucially, in equivocal VI-RADS 3–4 cases, DECT + D (AUC = 0.904) significantly outperformed VI-RADS (AUC = 0.652, p < 0.05), while standalone DECT achieved an AUC of 0.824. For D < 3 cm, DECT + D (AUC = 0.895) and DECT (AUC = 0.857) were comparable to VI-RADS (AUC = 0.866), but DECT maintained high specificity (0.934). A nomogram and web-based risk calculator were developed. Conclusion: The DECT-based model achieves diagnostic accuracy comparable to VI-RADS and demonstrates superior stability in clinically challenging subgroups. It serves as a robust, objective alternative for preoperative bladder cancer staging, particularly beneficial for patients with MRI contraindications. Critical relevance statement: This study demonstrates that a quantitative DECT-based model provides an accurate, objective alternative to MRI for preoperative bladder cancer staging, mitigating diagnostic ambiguity in clinically equivocal cases and ensuring accurate risk stratification in small lesions. Key Points: Preoperative differentiation of muscle invasion is critical for bladder cancer management. The DECT-based model yields diagnostic accuracy statistically comparable to VI-RADS. The DECT-based model improves diagnostic confidence in VI-RADS 3–4 lesions. Graphical

This study aims to measure myocardial blood flow (MBF) using dynamic CT- myocardial perfusion imaging (CT-MPI) combined with mental stressors in patients with obstructive coronary artery disease (OCAD) and in patients with anxiety and no obstructive coronary artery disease (ANOCAD). A total of 30 patients with OCAD with 30 patients with ANOCAD were included in this analysis. Using the 17-segment model, the rest and stress phase MBF of major coronary arteries in participants were recorded respectively. Compared with ANOCAD patients, OCAD patients were more likely to have localized reduction of MBF (p < 0.05). For patients with ANOCAD, both global MBF and MBF of the main coronary arteries in the stress phase were lower than those in the rest phase (all p < 0.05), but there was no significant difference in MBF among the main coronary arteries in the rest or stress phase (p = 0.25, p = 0.15). For patients with OCAD, the MBF of the target area was lower than that of the non-target area in both the rest and stress phase, and the MBF of the target area in the stress phase was lower than that in the rest phase (all p < 0.05). However, there was no significant difference in MBF between the rest or stress phase in the non-target area (p = 0.73). Under mental stress, the decrease in MBF in ANOCAD patients was diffuse, while the decrease in MBF in OCAD patients was localized. Dynamic CT-MPI combined with mental stressors can be used to detect MBF changes in anxiety patients.