Magnetic resonance imaging (MRI) is a sensitive method for assessing silicone implant integrity, with -weighted imaging being essential for detecting abnormalities in surrounding tissue. Silicone breast imaging protocols often require multiple tailored sequences for species suppression and diagnostic contrast. We propose a single sequence suitable for patients with or without implants that enables -weighted, high-quality imaging and three-species separation within a clinically feasible scan time. Our approach uses a 2D fast spin echo (FSE) sequence with seven bipolar multi-echo gradient echo readouts, enabling field mapping and water-fat-silicone separation. Incoherent - undersampling combined with joint multi-echo reconstruction leverages temporal correlations and applies compressed sensing regularization directly to the separated species. We achieve high-resolution, artifact-free water, fat, and silicone (WFS) images across three planes from one sequence, regardless of shim quality, and for different breast implant types. Compared to independent echo reconstruction and separation, joint multi-echo reconstruction with incoherent - sampling allows acceleration of , reducing scan time to 2.5 minutes. We demonstrate a robust -weighted technique that provides reliable water-fat-silicone imaging in 2.5 minutes, enabling uniform breast protocols for patients with and without silicone implants.

Ex vivo MRI allows for ultra-high resolution image acquisition and valuable validation when combined with histology. Postmortem brain samples may undergo long scan times without motion artifacts. Perfluoropolyethers such as Fomblin have become a popular choice of immersion liquid for their "proton free" appearance and their ability to eliminate susceptibility artifacts from the tissue-air interface but the effect of Fomblin on downstream histology experiments has not been previously studied. We exposed rat brain samples to Fomblin (n = 4) versus a control group (n = 4). Samples underwent histochemical (Nissl) and immunohistochemical staining for NeuN to assess neurons and background staining. The optical fractionator method was applied to assess total neuron counts and tissue thickness. Samples from the Fomblin group showed consistent NeuN and Nissl staining when compared to the control group. The staining color, evenness, and neuron visualization appeared unaffected with no background staining. The total neuron counts, and tissue thickness showed only slight differences in absolute numbers between groups with insufficient evidence to conclude the distribution of total neuron number or tissue thickness differed by group. These data suggest that Fomblin may not negatively impact histochemical staining, immunohistochemistry, or total neuron counts in the short term.

This work investigated the performance of MRI Faraday cages (FCs) over the lifetime of clinical MRI systems, aiming to better inform an option to repurpose an existing FC when an MRI scanner is replaced. FC performance was measured at acceptance testing for 40 MRI systems and for a further 11 MRI systems of various ages. Results were compared with the MRI vendor's FC specification and with measurements made when the FCs were initially built. The majority of FCs, 63% (n = 25), had at least one measurement below specification at acceptance testing. However, no RF artefacts were observed on MR images. There were significant negative relationships between FC performance and age at the locations of the door and window (p < 0.001). FC performance can degrade between the time of FC manufacture and initial clinical MRI scanning. However, FC attenuation levels may need to be considerably less than specification values before external RF artefacts start appearing on MR images in practice. Further degradation of FC performance may occur over time, but this may be better addressed by maintenance on the MR exam room door rather than a much more costly and time-consuming replacement of the FC.

This feasibility study presents the diagnostic accuracy of a novel dental-dedicated magnetic resonance imaging (ddMRI) system for assessing pulp vitality and diagnosing apical periodontitis (AP), as an adjunct to clinical assessment and cone beam CT (CBCT) imaging. Ten consecutive patients with possible endodontic problems were screened, and ultimately 18 teeth in nine patients (10 healthy teeth, five necrotic teeth with suspected AP and three necrotic or root canal treated teeth with no suspicion of AP) with a recent CBCT were included. The teeth were tested for vitality and clinical signs of AP. The CBCT volumes were assessed by three trained observers for signs of AP. The teeth were scanned using the Magnetom Free.Max Dental Edition ddMRI system (Siemens Healthineers, Forchheim, Germany), operating at 0.55 T with a seven-channel dental-dedicated surface coil. Six pulse sequences optimised for periapical diagnostics were applied, with a total scanning time of approximately 18 min per tooth. Images were assessed by three trained observers for anatomical structure conspicuity (root tip, periapical bone and lamina dura), pulp vitality determined by presence of signal and presence of AP determined by accumulation of fluid in the periapical area. The assessed pulp vitality status and presence of AP on ddMRI were compared to the clinical and radiological findings. Inter-modality agreement was calculated using kappa statistics, and diagnostic accuracy was evaluated with consensus between clinical findings and CBCT imaging as the reference standard. All anatomical structures were visible in all cases. ddMRI showed high diagnostic accuracy. For pulp vitality, the inter-modality agreement kappa was 0.77 and accuracy was 0.88. For AP, the inter-modality agreement kappa was 0.87 and accuracy was 0.94. ddMRI show promising results as a non-ionising imaging modality for assessment of pulp vitality and diagnosis of AP. This feasibility study demonstrates the potential of ddMRI to provide accurate diagnostic support, laying a foundation for larger-scale validation studies and clinical applications.

This study aimed to assess the imaging performance of a 3D CZT SPECT/CT system for Tb-161 and compare its quantitative accuracy and image quality with those of a conventional [NaI(Tl)]-based SPECT/CT system. A NEMA Image Quality (IQ) phantom was scanned with a 3D CZT SPECT/CT (Veriton, Spectrum Dynamics) for 8min per bed position and with a conventional SPECT/CT (Symbia T16, by Siemens) for 16min per bed position. The 3D CZT SPECT acquisition time was virtually shortened by reparsing the listmode data. The NEMA IQ phantom was scanned with a cold background and with a sphere-to-background ratio (SBR) of 20:1 and 10:1, with 0.71 MBq/mL in the spheres. Clinical reconstruction protocols were chosen by maximizing the SBR (for the four largest spheres) while minimizing the background noise. The optimal SBR-to-noise trade-off was achieved at 48 updates for the Symbia and 50 updates for the Veriton. The Veriton exhibited a 20% and 34% higher SBR with a 19% and 10% lower CoV compared to the Symbia for the 10:1 and 20:1 spheres to background ratios, respectively. The calibration factors were determined as 15.17 and 4.8 [Formula: see text]cps/MBq for the Symbia and Veriton, respectively. Reducing the scan time had minimal effect on SBR, but a twofold count reduction increased background noise by 11%. Quantitative Tb-161 SPECT imaging can be performed using both a conventional and a 3D CZT SPECT/CT. Given its higher sensitivity, the 3D CZT system is preferred, as it achieved better image quality with an 8-min acquisition compared to a conventional system with a 16-min acquisition.

To mitigate artifacts related to motion and field changes in high-resolution -weighted human brain imaging using servo navigation at ultra-high fields up to 11.7 T. MR-based servo navigators were integrated into a segmented 3D-EPI sequence to allow for prospective correction of involuntary head motion and first-order shim changes. Seven subjects were scanned with whole-brain protocols at 0.3 mm isotropic resolution with and without correction at 7 and 11.7 T. Validation was performed on detailed brain vasculature in scans with involuntary motion. Blurring of small veins was reduced by servo navigation for all subjects and across field strengths. In case of involuntary large motion, the method preserved image quality, while uncorrected motion led to severe artifacts. In case of microscopic motion, reduced blurring and shading in the frontal lobe demonstrate the additional benefit of prospective field drift correction. Servo-navigated segmented 3D-EPI improves 0.3 mm isotropic whole-brain -weighted imaging under realistic motion and field changes within 5.5 to 11 min scan time at 11.7 and 7 T.

Chemical exchange saturation transfer (CEST) is a promising magnetic resonance imaging (MRI) technique that provides molecular-level information in vivo. To obtain this unique contrast, repeated acquisition at multiple frequency offsets is needed, resulting a long scanning time. In this study, we propose a hybrid strategy at k-space and image domain to accelerate CEST MRI to facilitate its wider application. In k-space, we developed a complementary undersampling strategy which enforces adjacent frequency offsets by acquiring different subregions of k-space. Both Cartesian and spiral k-space trajectories were applied to validate its effectiveness. In the image domain, we developed a multi-offset transformer reconstruction network that uses complementary information from adjacent frequency offsets to improve reconstruction performance. Additionally, we introduced a data consistency layer to preserve undersampled k-space and a differentiable coil combination layer to leverage multi-coil information. The proposed method was evaluated on rodent brain and multi-coil human brain CEST images from both pre-clinical and clinical 3 T MRI scanners. Compared to fully-sampled images, our method outperforms a number of state-of-the-art CEST MRI reconstruction methods in bothaccuracy and image fidelity. CEST maps, including amide proton transfer (APT) and relayed nuclear Overhauser enhancement (rNOE), were calculated. The results also showed close agreement with fully-sampled ones.

ABSTRACT The Stealth Address Protocol (SAP) allows users to receive assets through stealth addresses that are unlinkable to their stealth meta-addresses. The most widely used SAP, Dual-Key SAP (DKSAP), and the most performant SAP, Elliptic Curve Pairing Dual-Key SAP (ECPDKSAP), are based on elliptic curve cryptography, which is vulnerable to quantum attacks. These protocols depend on the elliptic curve discrete logarithm problem, which could be efficiently solved on a sufficiently powerful quantum computer using the Shor algorithm. In this paper, three novel post-quantum SAPs based on lattice-based cryptography are presented: LWE SAP, Ring-LWE SAP and Module-LWE SAP. Among them, the Module-LWE SAP, which is based on the Kyber key encapsulation mechanism and Dilithium signature scheme, achieves a 67% scan-time improvement over ECPDKSAP. In contrast to DKSAP and ECPDKSAP, the Module-LWE design achieves long-term quantum resistance through the hardness of Module-LWE and the post-quantum guarantees of Kyber and Dilithium. However, this improvement in scan time and the benefit of long-term post-quantum security come at the cost of substantially larger on-chain announcements and meta-addresses, resulting in a clear trade-off between computational efficiency, long-term security and storage cost.

Noninvasive measurement of the human brain’s angioarchitecture is essential for understanding functional neuroimaging signals, diagnosing cerebrovascular diseases, and tracking neurodegeneration. Ultrahigh-field MRI now enables mesoscopic (<0.5 millimeters) imaging, revealing vascular details previously inaccessible in vivo. Yet current approaches face two barriers: Scan times often exceed 40 minutes, and the conventional visualization methods remain limited for navigating the vasculature. Here, we present a fast whole-brain MRI protocol that resolves the venous network at 0.35 millimeters in under 7 minutes. We also introduce processing and visualization techniques that distinguish vessel types and more intuitively navigate the vasculature. These advances allow in vivo reproduction of the seminal vasculature images of Henri M. Duvernoy and provide whole-brain intracortical meso-vein maps in humans. Our methods lay the groundwork for detailed examination of vascular organization across individuals, brain regions, and cortical layers. More generally, these methods make mesoscopic imaging of angioarchitecture viable for broad neuroscientific and clinical applications.

Diffusion-weighted imaging (DWI) of the head and neck is essential for various clinical applications but is often hampered by artifacts and reduced image quality. Deep learning (DL) reconstruction has the potential to enhance the quality of head and neck DWI. This study aims to evaluate the performance of an accelerated, DL-reconstructed DWI (DWIDL) in terms of image quality and diagnostic confidence. This retrospective study included patients who underwent clinically indicated head and neck DWI at 1.5 T and 3 T between August 2023 and January 2024 at atertiary care center. Imaging was performed at low b‑values (0 or 50 sec/mm2) and high b‑values (800 sec/mm2), and apparent diffusion coefficient (ADC) maps were computed. After acquiring standard single-shot echoplanar imaging DWI sequences, the raw MR datasets underwent simulated acceleration by reducing the number of signal averages. These accelerated exams were then reconstructed using anovel DL-based algorithm that combined DL-based k‑space to image reconstruction with DL-based super-resolution processing (DWIDL). Three readers analyzed the images using avisual Likert score to evaluate image sharpness, artifacts, noise, overall image quality, and diagnostic confidence. Comparisons were made using the Wilcoxon signed-rank test. Aquantitative analysis of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and apparent diffusion coefficient values (ADC) was also performed. The study included 30patients (mean age, 55 ± 19years; range, 24-84; 18men) with various pathologies. Scan times were reduced by 67% at 1.5 T and up to 55% at 3 T. The quantitative analysis revealed aminimal but statistically significant decrease in SNR and CNR in the deep learning-reconstructed images (p = 0.002 and p < 0.001, respectively). However, readers reported no significant differences between DWI and DWIDL regarding image quality parameters or diagnostic confidence for both low and high b‑value images, as well as the ADC (all p > 0.05). DL reconstruction of head and neck DWI is feasible, significantly reducing examination time without compromising image quality or diagnostic confidence. This technique enables accelerated and effective diagnostic DWI of the head and neck.

ABSTRACT The petroleum industry is a vital economic sector, and facilities that process crude oil and natural gas for end use are known as petrochemical or oil terminals. This manuscript presents Programming Logic Controller (PLC) with Supervisory Control and Data Acquisition (SCADA) System for Tracking Petroleum Terminals in Industry using RBAGCN-PLC-SCADA. This study utilises data from petroleum terminal dataset and employs tracking technique as PLC-SCADA compared to traditional ladder diagrams, to produce simpler structure, fewer rungs, less processor memory, and faster execution times. Then, RBAGCN is used for prediction, estimating ladder diagram number, program size, and scan time with weights optimized by Giraffe Kicking Optimization (GKO). The proposed RBAGCN-PLC-SCADA method is implemented in MATLAB and evaluated using accuracy, precision, error, sensitivity, specificity, F1-score, and computational time, achieving 98% accuracy, 0.05% error, 98% F1-score, 97% precision, 99% sensitivity, and 97% specificity in petroleum terminal industry. The proposed method shows better results in all existing systems like monitoring industrial reactors using capacitance with long-short term memory (MIREC-LSTM), supervised anomaly detection in physical model with multilayer perceptron (SADP-MLP) and PLC system for rumaila degassing stations with recurrent neural network (PLC-RNN). The results show that proposed RBAGCN-PLC-SCADA method achieves lower error rate than existing methods.

To develop and validate a rapid, fully automated method for shimming of the lung. For field mapping of the lung, a custom 2D RF spoiled gradient echo sequence was used offering sub-millisecond echo times. At 3T, four echo-shifted coronal images were acquired with a minimum TE of 0.57 ms and an inter-echo spacing of 0.1 ms. Imaging was performed in free-breathing using three repetitions with a total scan time of 4.2 s. Subsequently, motion correction, field mapping, lung segmentation, and lung shim currents were calculated inline. Finally, the derived shim currents were saved locally, accessible by any custom sequence for application during scan preparation. The shimming method's performance was compared against the vendor's default settings in five healthy volunteers for functional lung imaging with matrix pencil decomposition using balanced steady-state free precession (bSSFP). Field mapping and shimming of the lung was successfully performed in all volunteers and derivation of shim currents took less than 10s. At 3T, subject-specific shimming reduced the mean frequency offset in the lung by up to 45 Hz and the frequency range (max-min) by up to 180 Hz. Overall, this improved bSSFP signal homogeneity, resulting in more uniform functional images. This work demonstrates a robust, automated shimming solution for lung imaging at 3T, easily integrable into clinical workflows. The technique significantly enhances image quality and reliability for high-field, bSSFP-based pulmonary imaging. At lower field strengths, the method can possibly relax TR constraints, reducing SAR and peripheral nerve stimulation.

Medical education in fetal echocardiography for OB/GYN residents.

X-ray fluorescence (XRF) imaging is a promising modality for quantitative molecular imaging that allows for the in vivo biodistribution detection of specific elements within biological systems. Despite its potential, challenges such as detection limit and scan time have hindered its widespread adoption in preclinical in vivo imaging. This study aims to address these challenges by developing a benchtop 2D multi-pinhole XRF imaging system with an up-to-date cadmium zinc telluride (CZT) detector system without tomographic reconstruction. The benchtop 2D multi-pinhole XRF imaging system was implemented by integrating a High Energy x-ray Imaging Technology (HEXITEC) 2 × 2 CZT detector system with a lead collimator containing four tungsten pinholes. 140kV fan beam x-rays irradiated a small-animal-sized polymethyl methacrylate (PMMA) phantom filled with gold nanoparticle (GNP) solutions at concentrations of 0.156, 0.313, 0.625, 1.25, 2.5, and 5.0mg/mL. A GNP-loaded phantom with varying concentrations was used to establish a calibration curve relating GNP concentrations to K-shell XRF photon counts and to evaluate the detection limit of the system. The multi-pinhole collimator generated four well-aligned, nonoverlapping projections, each centered on a CZT module, resulting in a fourfold increase in photon detection efficiency compared with a single-pinhole collimator. The detector exhibited excellent spectral performance with an energy resolution of 1.38±0.32keV full width at half maximum (FWHM) at 59.5keV. As a result, two gold XRF peaks (67.0 and 68.8keV) were well resolved. Reconstructed XRF images, generated by combining four projections using the maximum likelihood expectation maximization algorithm, showed a strong linear relationship between GNP concentrations and XRF photon counts (R2>0.99). The benchtop 2D multi-pinhole XRF imaging system demonstrated in this study achieved a detection limit of 0.105mg/mL with a scan time of 10min and an imaging dose of 51.5 cGy. By successfully integrating a multi-pinhole collimator with the HEXITEC 2 × 2 CZT detector system, the benchtop 2D multi-pinhole XRF imaging system substantially improved system sensitivity, achieving a detection limit of 0.1mg/mL for GNPs, a biologically relevant concentration, in a small-animal-sized phantom. This detection limit was attained with a 10-min scan time and an imaging dose of 51.5 cGy, both within the acceptable range for in vivo imaging applications. These results highlight the potential of the benchtop 2D multi-pinhole XRF imaging system for preclinical in vivo applications.

Rapid whole brain motion-robust mesoscale in-vivo MR imaging using multi-scale implicit neural representation.

The aim of this study was to describe the normal anatomy of coelomic organs in three different species of chelonians using high-field magnetic resonance imaging (MRI). This study also describes a rapid study protocol to examine chelonians without the use of sedation. A 1.5-T superconducting magnet with volume or surface coils was used for the study. Sixteen healthy turtles belonging to three different species: 3 yellow-bellied sliders (Trachemys scripta scripta), 3 marginated tortoise (Testudo marginata), and 10 Hermann's tortoises (Testudo hermanni) were considered. The images were obtained using the following sequences: T1-weighted (T1W) turbo spin echo (TSE) acquired in the transverse and dorsal planes, T2-weighted (T2W) TSE 3D acquired in the sagittal plane, and short-tau inversion recovery (STIR) in the transverse plane. No contrast medium was used. All studies were feasible, fast, and yielded images of good quality in all the sequences. TSE T2W images had the best signal-to-noise ratio. The scan time was approximately 15-20min. The majority of the coelomic organs were clearly identified, with the exception of the pancreas, adrenal glands, and ureters. In conclusion, high-field MRI in unsedated chelonians is feasible and fast and yields diagnostic images of the majority of the coelomic organs in all three species evaluated.

Artificial intelligence in 4D flow MRI: Review of technological aspects and clinical applications.

The role of AI in optimizing CMR image quality: A scoping review.

Reinforced physiology-informed learning for image completion from partial-frame dynamic PET imaging.

To propose a novel highly efficient isotropic-resolution 3D whole-heart saturation-recovery and variable-flip-angle (SAVA) T1 mapping sequence at 0.55 T, incorporating image navigator (iNAV)-based non-rigid motion correction and dictionary matching. The proposed iNAV-based isotropic-resolution 3D whole-heart SAVA T1 mapping sequence at 0.55 T acquires three gradient echo T1-weighted volumes sequentially: an equilibrium contrast with 4° flip angle, and two saturation recovery T1-weighted contrasts with 10° flip angles and different saturation delays. Sequence parameters were optimized for the lower field strength by simulations and phantom experiments. Two-dimensional iNAVs are acquired at each heartbeat to enable respiratory motion estimation and correction and 100% respiratory scan efficiency. The T1 mapping is computed by dictionary matching, using subject-specific dictionaries based on Bloch equations simulations. Non-rigid motion correction is implemented based on respiratory bins reconstructed by iterative-SENSE and subsequent patch-based low-rank denoising, for each contrast separately. The proposed approach was evaluated in a standardized T1 phantom and 10 healthy subjects, in comparison to spin-echo reference and 2D MOLLI, respectively. Excellent agreement is observed between iNAV-based SAVA T1 mapping at 0.55 T and spin echo reference in phantom, with a for all phantom vials. Good image quality was obtained in vivo for the contrast images and corresponding T1 maps in a scan time of 6:30 min ±40 s. Average and SD of myocardial T1 values across subjects and segments was 706 ± 41 ms, which is comparable to acquired 2D MOLLI values of 681 ± 26 ms, and previously reported 2D MOLLI values of 701 ± 24 ms. Coefficient of variation values (12%) are higher than those previously reported for diaphragmatic navigator-based non-isotropic SAVA T1 mapping at 3 T (7.4%). The proposed iNAV-based SAVA approach achieves free-breathing motion-corrected 3D whole-heart T1 mapping at 0.55 T in approximately 7 min scan time for an isotropic resolution of 2 mm. In vivo experiments showed that the proposed sequence achieves good map quality, with comparable T1 values and spatial variability compared to 2D MOLLI T1 mapping. Further evaluation is warranted in patients with cardiovascular disease.