Diagnostic and Interventional Imaging最新文献

Purpose: The purpose of this study was to assess the benefit of a deep learning-based image reconstruction (DLBIR) for improving image quality in orbital magnetic resonance imaging (MRI) at 3 Tesla (T).

Materials and methods: Seventy-one patients (48 women and 23 men) with a mean age of 52 ± 19.5 (standard deviation [SD]) years (age range: 7-90 years) who underwent MRI examination of the orbit at 3 T between January and June of 2024, were included in the study. Coronal T2-weighted MR images obtained in 70 patients and post-contrast fat-saturated (FS) coronal T1-weighted MR images obtained in 25 patients, were reconstructed with and without DLBIR, resulting in four imaging sets. Two radiologists independently and blindly measured the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the optic nerves on the four imaging sets. Image quality and orbital abnormalities were assessed using a standardized 5-point Likert scale. Comparisons between MR images obtained with and without DLBIR were performed using Wilcoxon test for ordinal and quantitative variables and McNemar test for paired binary data.

Results: SNR and CNR of coronal T2-weighted MR images were significantly greater using DLBIR (26.67 ± 9.03 [SD], and 14.87 ± 10.31 [SD], respectively) than without DLBIR (18.91 ± 7.28 [SD], and 9.78 ± 8.47 [SD], respectively) (P < 0.001). There were no differences in SNR and CNR between post-contrast FS T1-weighted images obtained with DLBIR (85.56 ± 63.13 [SD], and 64 ± 41.38 [SD], respectively) and those obtained without DLBIR (91.36 ± 48.49 [SD], and 43.25 ± 20.4 [SD], respectively) (P = 0.35, and P = 0.14, respectively). Qualitatively, good-to-excellent image quality was obtained more frequently with DLBIR than without DLBIR for T2-weighted and post-contrast FS T1-weighted images with respect to optic nerve sharpness (67 % vs. 16 %, and 8 % vs. 0 %, respectively), brain sharpness (90 % vs. 6 %, and 68 % vs. 4 %, respectively), and overall image quality (73 % vs. 1 % and 36 % vs. 0 %, respectively) (all P ≤ 0.001). No significant differences in the detection rates of orbital abnormalities were found between MR images obtained with and without DLBIR, including optic nerve hyperintensity (34 % vs. 31 %, respectively; P = 0.16) and optic nerve atrophy (33 % for both) on T2-weighted images, and optic nerve enhancement on post-contrast FS T1-weighted images (16 % for both).

Conclusion: DLBIR significantly improves image quality of MRI examinations of the orbit at 3 T, without losing clinically relevant information.

Remarkable progress has been made in the endovascular management of atherosclerotic lesions in recent decades. Despite initial challenges, such as arterial dissection and acute thrombosis, successive technological innovations have led to the development of stents designed to minimize the risk of restenosis and occlusion. Percutaneous transluminal angioplasty, combined with antiplatelet regimens and management of cardiovascular risk factors, is now at the forefront of symptomatic arteriosclerotic lesion treatment. However, a persistent limitation of percutaneous transluminal angioplasty is the permanent implantation of metallic stents. The long-term presence of metallic stents requires prolonged antiplatelet therapy, creates artifacts on imaging, and is associated with late or very late stent failure. All these conditions are linked to significant morbidity and mortality. The purpose of this review was to provide interventional practitioners with a comprehensive overview of the need for bioresorbable stents in interventional radiology practice by briefly reviewing the vascular healing process, and the factors contributing to stent failure, including patient- and stent-related factors, and by exploring the emergence of bioresorbable stents as the next frontier in endovascular therapy. This article illustrates and discusses how bioresorbable scaffolds could transform the landscape of endovascular interventional radiology from head to toe by retracing the major milestones in bioresorbable scaffold development, outlining future technical improvements, and highlighting current clinical evidence and future perspectives.

Dynamic contrast-enhanced magnetic resonance imaging remains a cornerstone of breast cancer diagnosis, yet concerns regarding the safety, environmental impact, and cost of gadolinium-based contrast agents are driving the development of gadolinium-based contrast agent-free alternatives. This review outlines emerging non-contrast imaging modalities that support a more sustainable approach to breast cancer diagnosis. Advanced MRI techniques, such as diffusion-weighted imaging and synthetic MRI, provide detailed tissue characterization without the need for contrast agents. In computed tomography (CT), innovations including dual-energy CT and photon-counting detector CT are improving lesion detection and characterization, with photon-counting detector CT offering exceptional spatial resolution. Molecular imaging with positron emission tomography is also advancing beyond ¹⁸F-fluorodeoxyglucose, incorporating dedicated high-resolution systems and novel tracers targeting specific biomarkers, such as 16α-¹⁸F-fluoro-17β-estradiol for estrogen receptors, fibroblast activation protein inhibitors, and human epidermal growth factor receptor 2-targeted agents. The future of breast imaging is likely to adopt a multimodal strategy, combining these innovations to deliver more accurate, personalized, and sustainable patient care.

Purpose: The purpose of this study was to evaluate the feasibility and diagnostic performance of stress myocardial perfusion imaging (MPI) using a first-generation dual-source photon-counting CT (PCCT) scanner by comparison with reference standards.

Materials and methods: Consecutive patients referred for coronary CT angiography (CCTA) with concomitant stress MPI using PCCT scanner and at least one functional reference test within one month were included. Static PCCT-MPI with regadenoson (Rapiscan, GE Healthcare) was acquired 12 s after the intravenous administration of 40 mL of iodinated contrast material and paired with myocardial delayed enhancement imaging. Reference tests for ischemia included stress cardiac magnetic resonance imaging, stress echocardiography, single-photon emission computed tomography, or invasive coronary angiography. Diagnostic performance was evaluated using sensitivity, specificity, accuracy, areas under receiver operating characteristic curve analysis (AUC) as well as Youden index-derived thresholds.

Results: Forty-one patients were included. There were 28 men and 13 women with a median age of 62 years (Q1, 57; Q3, 70; range: 18-85 years). Of these, 35 patients (85 %) had obstructive coronary artery disease (CAD) on CCTA. PCCT-MPI identified myocardial hypoperfusion in 18 patients (44 %) with a median dose-length product of 97 mGy.cm (Q1, 76.8; Q3, 155.8). Visual assessment yielded 100 % sensitivity (95 % confidence interval [CI]: 81-100 %) and 96 % specificity (95 % CI: 78-100 %), with an AUC of 0.98 (95 % CI: 0.93-1.00) for the diagnosis of ischemic and infarcted myocardium. An optimal defect-to-remote iodine ratio cutoff of 0.79 showed 98 % accuracy (95 % CI: 87-100 %) and an AUC of 0.99 (95 % CI: 0.98-1.00 %). Integration of PCCT-MPI with CCTA could have obviated additional functional testing or invasive angiography in up to 50 % of patients with obstructive CAD.

Conclusion: Stress static PCCT-MPI is feasible and demonstrates excellent diagnostic accuracy for detecting myocardial ischemia. Defect-to-remote iodine ratio from spectral imaging further enhances performance, establishing PCCT as a comprehensive imaging modality that unifies anatomic and functional coronary assessment at a reasonable radiation dose, within a single examination.

Purpose: The purpose of this prospective study was to evaluate the diagnostic performance of dual-energy computed tomography (DECT) using a dual-layer detector scanner in assessing the pathological response of peritoneal metastases (PMs) from non-mucinous colorectal cancer to neoadjuvant chemotherapy (NAC).

Materials and methods: Consecutive patients with PMs from non-mucinous colorectal cancer who underwent preoperative DECT using a dual-layer detector scanner before cytoreductive surgery were prospectively included. Virtual monoenergetic images at 40 keV (VMI_40kev), VMIs at 100 keV (VMI_100kev), VMI slope (VMI_slope), iodine concentration (IC), normalized iodine concentration with aorta (nIC_aorta) and liver (nIC_liver), effective Z atomic number (Z_eff), and extracellular volume fraction (ECVf) were evaluated on PMs by two radiologists. Pathological response of PM was classified using the peritoneal regression grading score (PRGS), and classified as either good (complete response or major histological regression - PRGS ½) or poor (minor or no histological response - PRGS ¾) responses. DECT variables of PMs with good responses were compared to those of PMs with poor responses using independent-sample t-tests. Receiver operating characteristic curves were built to estimate the capabilities of the different DECT variables in differentiating between PMs with good responses (PRGS ½) and those with poor responses (PRGS ¾). Intra-class correlation coefficients analyses were performed to estimate interobserver variability in DECT variable measurements.

Results: Forty-four patients (22 men median age, 62 years; age range: 35-78 years) with 77 PM were included from September 1st 2023 to July 1st 2025. Thirty-nine out of 77 PMs (51 %) exhibited good response (PRGS ½) and 38 PMs (49 %) exhibited poor response (PRGS ¾). VMI_40kev, VMI_slope, IC, nIC_aorta, nIC_liver, ECVf were significantly greater in PRGS ¾ PMs by comparison with PRGS ½ (P < 0.05). The best AUC values to distinguish between good and poor pathological response of PMs were obtained with nIC_aorta (AUC, 0.74: 95 % confidence interval [CI]: 0.63-0.85) and ECVf (AUC, 0.74; 95 % CI: 0.63-0.84). ICC was > 0.8 for most DECT variables.

Conclusion: DECT using a dual-layer detector scanner provides promising biomarkers for predicting pathological response in non-mucinous PM after chemotherapy.