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The limited sample size in gait studies has hampered progress in the field. This challenge could be addressed through multicenter studies, thereby leveraging data sets from different laboratories. This study compared 3-dimensional lower-extremity running kinematics between the Biomechanics and Motor Control Laboratory, Federal University of ABC (Brazil), and the Running Injury Clinic, University of Calgary (Canada). Three-dimensional lower-extremity kinematics from 23 male runners were collected from each laboratory using comparable instrumentation and experimental procedures. The 3-dimensional hip, knee, and ankle angles were compared within and between centers using root-mean-square deviation. Two-sample t tests Statistical Parametric Mapping tested the hypothesis that the data from both laboratories were not different. The sagittal plane hip, knee, and ankle angles were similar between laboratories, while notable differences were observed for frontal (hip and ankle) and transverse (hip and knee) plane angles. The average interlaboratory root-mean-square deviation (2.6°) was lower than the intralaboratory root-mean-square deviation (Biomechanics and Motor Control = 4.8°, Running Injury Clinic = 5.6°), with the ankle transverse angle displaying the smallest, and the knee transverse angle displaying the largest variability. This study demonstrates the potential of combining gait kinematics data from different laboratories to increase sample size, but frontal and transverse plane data should be considered with caution. [ABSTRACT FROM AUTHOR]

We present a comprehensive guide to light-sheet microscopy (LSM) to assist scientists in navigating the practical implementation of this microscopy technique. Emphasizing the applicability of LSM to image both static microscale and nanoscale features, as well as diffusion dynamics, we present the fundamental concepts of microscopy, progressing through beam profile considerations, to image reconstruction. We outline key practical decisions in constructing a home-built system and provide insight into the alignment and calibration processes. We briefly discuss the conditions necessary for constructing a continuous 3D image and introduce our home-built code for data analysis. By providing this guide, we aim to alleviate the challenges associated with designing and constructing LSM systems and offer scientists new to LSM a valuable resource in navigating this complex field. [ABSTRACT FROM AUTHOR]

Purpose: This study assessed the accuracy of linear measurements and dental implant selection performed in a smartphone application compared to a computer software. Materials and Methods: Forty-four DICOM files from the posterior mandible in partially edentulous patients were evaluated by three trained and calibrated examiners. Images were analyzed using three visualization methods: cross-sectional view (CScr) and coronal (CSco) plane using the CS 3D Imaging software, and coronal (DRco) plane using the DroidRender smartphone application. For standardization, bone width and height measurements were taken in the edentulous posterior mandible, 10 mm posterior to the mental foramen. Implants were selected according to the 2022/2023Straumann Standard implant catalog. Linear measurements were compared using repeated-measures ANOVA, and implant selection was compared using Friedman test. Statistical analysis was performed using SPSS software, with a significance level of 5%. Results: Linear measurements showed a statistically significant difference for bone width (P = .030), but not for height (P = .685). The choice of implant was not influenced by the visualization method (P = .614). Conclusions: It is possible to suggest the use of smartphone applications as an additional diagnostic tool for DICOM evaluation and implant planning in the posterior mandible. Smartphone applications allow an assessment not limited to 2D images or to static environments. Therefore, information exchange and diagnostic opinion in emergency situations may be facilitated. [ABSTRACT FROM AUTHOR]

Traditional LEDs emit light that exhibits incoherence and displays a Lambertian distribution. To achieve linearly polarized (LP) light and control the emission direction, a variety of optical components are required to be stacked, which is unsuitable for compact applications and results in low deflection efficiency. Here, we propose and and numerically simulate a novel single-chip micro-resonant cavity LED (micro-RCLED) device that generates directional LP light by integrating a continuous metasurface. This device includes a bilayer grating at the GaN layer's bottom, providing high transverse electric (TE) reflectivity above 89.5% and an extinction ratio exceeds 57 dB at 500 nm. The top distributed Bragg reflector (DBR) and the bilayer grating together constitute a TE mode Fabry–Pérot resonant cavity. This not only promotes the emission of the TE wave, but also guarantees its collimation with the appropriate phase, thereby enhancing its spatial coherence. A functional metasurface above the DBR layer precisely controls the TE wave's deflection angle. It maintains a low aspect ratio while enabling efficient, large-angle deflection. The simulation results demonstrate that this device provides an effective solution for generating highly spatially coherent directional LP light, with broad potential applications in fields such as polarized light imaging and advanced 3D micro-LED display systems. [ABSTRACT FROM AUTHOR]

Objective: This pilot study aimed to evaluate, for the first time, the changes in facial tissues following the placement of a single dental implant. Method and materials: Patients were scanned with a 3D facial scanner (3dMD) before implant surgery, immediately after surgery (T1), at 7 days postoperatively (T2), and at the impression stage (T3). Acquired images were processed using the 3dMDvultus (3dMD) software program and volume differences and linear depth measurements were calculated to determine the morphometric changes over time. A total of 11 patients were included in the analyses. Descriptive statistics were employed to analyze the data. Results: The volumetric changes and maximum depth differences indicated an initial increase, followed by a progressive decrease in tissue volume after implant placement in the area of the surgery. The volume change values ranged between 2.5 and 3.9 cm³ for T1, whereas for T2, the volume change decreased to a range of 0.8 to 1.8 cm³. Maximum depth differences ranged between 2.06 and 2.80 mm in the soft tissues immediately after the implant surgery and reduced to around 2.01 to 0.55 mm at the impression stage. The amount of painkiller used was not related to the magnitude of linear depth measurements at any assessed time point. Conclusion: There was a longitudinal decrease in soft tissue volume and depth difference in extraoral soft tissues in the region of implant placement after surgery up to 6 weeks. The use of a facial scanner is a promising noninvasive method to monitor 3D morphometric changes after implant surgery. [ABSTRACT FROM AUTHOR]

Purpose: To describe the use of digital technology to surgically guide the shell technique using allogenic cortical plates for a fully guided bone augmentation procedure. Materials and Methods: A total of 10 patients who required bone augmentation for implant placement were included in this study. Allogenic cortical plates were planned using CAD/CAM to have identical thickness to the original cortical plates, then were digitally positioned and shaped to outline the bone defect according to the existing anatomical details. A cutting pattern and a surgical template were manufactured according to the digitally preplanned bone graft and the intraoral setting. Results: A total of 12 horizontal bone grafting procedures were performed using the shell technique with allogenic cortical plates. All grafting procedures were deemed successful and allowed for ideal 3D implant positioning. Of the 12 bone grafting procedures, which used a surgical template to position the cortical plate, 3 required an adjustment to reposition the plate to a more ideal position. Conclusions: Digital technology was used to create a surgical template to guide the shell bone grafting technique with allogenic cortical plates. All surgical templates offered a fixed support to hold the cortical allogenic plate in the preplanned position, offering a predictable, simplified, and accurate guided bone grafting procedure. Further studies on a larger population of patients are necessary to assess those results and to verify the treatment approach described in this study. [ABSTRACT FROM AUTHOR]

Purpose: To validate an innovative 3D volumetric method of evaluating tissue changes proposed by Lee et al in 2020 by comparing the results of this method--in which the scanned peri-implant surfaces were transformed, visualized, and analyzed as 3D objects--to the results reported by an existing method based on calculation of the mean distance between measured surfaces. The null hypothesis was that there was no statistically significant difference between the two methods. Additionally, the present study evaluated peri-implant tissue changes 5 years after single implant placement in the esthetic zone. Materials and Methods: Both methods were applied to 11 oral implant site casts (6 maxillary central incisor sites, 5 maxillary lateral incisor sites) taken from 11 patients at crown placement and at follow-up examinations 5 years later. The methods are based on digital workflows in which the reference and 5-year casts are scanned and the resulting STL files are superimposed and analyzed for three regions of interest (mesial papilla, central area, and distal papilla). The volumetric changes reported by the Lee et al method and the mean distance method were calculated and compared using the Spearman rank correlation coefficient (P < .01) and the Wilcoxon signed-rank test (P < .05). Results: The correlation between the two sets of measurements was very high (Spearman rank correlation coefficient = 0.885). The new volumetric method indicated a mean volume loss of 2.82 mm3 (SD: 5.06), while the method based on the measurement of mean distance showed a mean volume loss of 2.92 mm3 (SD: 4.43; Wilcoxon signed-rank test result: P = .77). No statistically significant difference was found. The two methods gave equivalent results, and the null hypothesis was accepted. Conclusions: The new volumetric method was validated and can be considered a trustworthy tool. [ABSTRACT FROM AUTHOR]

Extraction-site alveolar remodeling is a major concern due to negative volumetric hard and soft tissue changes that inevitably limit rehabilitation options and diminish esthetic outcomes. Surgical techniques employed to minimize alveolar dimensional changes are not always predictable. Utilizing a socket shield with an immediate surgical implant procedure helps maintain a thin portion of the root in the vestibular area and thus minimizes bone resorption, especially at the coronal cortical aspect. This case series assesses the dimensional changes in peri-alveolar structures via superimposition of the preoperative and 6-month postoperative 3D digital quantification of soft tissue. Fifty patients with 50 sites fulfilled the inclusion criteria. Implant survival was 100%, with no incidence of complications. Tissue changes were as follows: -0.85 mm at the mesial papilla, -0.95 mm at the distal papilla, -0.7 mm at both the vertical and horizontal central margins, -0.21 mm at a distance 4 mm from the margin, and -0.64 mm at the palatal central margin. The buccal contour was clinically convex in all cases. The site with highest frequency of > 1 mm of dimensional loss was the distal papilla (42% of sites), and the site with the lowest frequency was the point 4 mm from the midfacial margin (0% of sites). [ABSTRACT FROM AUTHOR]

Advanced digital technologies have rapidly been integrated into prosthodontics to improve the digital workflow for prosthetic rehabilitation. The integration of 3D datasets acquired from various imaging sources such as intraoral scanners and facial optical scanners allows the creation of virtual patients to perform presurgical simulation and prosthetic rehabilitation. The presented technique introduced a straightforward protocol for aligning intraoral scans (Trios 4, 3Shape) to optical face scans (Face Hunter, Zirkonzahn) using a global best-fit algorithm of 3D evaluation software (GOM Inspect). Nasal geometry data were used as the matching reference to produce virtual dental patients. This integration protocol ensured that the intraoral scanner (Trios 4, 3Shape) was used not only to scan dental arches but also used effectively to scan the nose. These scans along with professional facial scans can be successfully aligned to produce virtual dental patients. As only a single fully dentate patient case with an alignment deviation of 243.6 µm was used, further research to evaluate the accuracy of this protocol is needed. [ABSTRACT FROM AUTHOR]

The role of threading dislocations in the intrinsic degradation of lateral GaN devices during high reverse bias stress tests (RBSTs) is largely unknown. We now present the results on lateral p-GaN/AlGaN/2DEG heterojunctions with a width of 200 μm in GaN-on-Si. A time-dependent permanent degradation of the heterojunction under high reverse bias and elevated temperatures can be observed, ultimately leading to a hard breakdown and device destruction. By using an integrated series p-GaN resistor, the device is protected from destruction and, consequently, the influence of dislocations on the degradation mechanism could be studied. Localization by emission microscopy could show that the transient current increase during a RBST is the result of the creation of a limited amount of highly localized leakage paths along the whole device width. We could establish a 1:1 correlation of leakage sites with a structural material degradation within the AlGaN barrier for nine individual positions on two different devices by planar transmission electron microscopy analysis. To unambiguously show whether dislocations in GaN-on-Si even should be considered a potential trigger for the RBST degradation in lateral heterojunctions, a combined planar and cross-sectional lamella approach was used for the first time for larger devices. This enabled the visualization of the three-dimensional propagation path of the dislocations close to the degradation sites. It was found that there is no statistically significant link between the material degradation and pre-existing dislocations. Our findings offer new insights into the GaN-on-Si material system, upon which upcoming power technologies are built upon. [ABSTRACT FROM AUTHOR]

Purpose: To determine the accuracy of dental implant placement using haptic robotic guidance in a large clinical series. Materials and Methods: In a prospective single-arm clinical study, 108 patients received 273 individual endosteal implants. A virtual preoperative restorative and surgical plan was created from a CBCT scan and matched to the surgical workspace on the day of surgery via either a tooth-based or bone-based fiducial splint. Intraoperatively, the surgeon manipulated a handpiece attached to a haptic robotic guidance arm. A variety of drills and implants were used. Both the osteotomy and the implant placement were guided by 3D haptic constraints according to the virtual plan. Postoperative CBCT scans permitted the calculation of the actual implant placement deviations compared to the plan for accuracy. Precision was calculated by comparing SDs from published literature. Results: The implants were evenly distributed by arch, with 47% placed in the maxilla and 53% in the mandible. The mean ± SD signed depth deviation was 0.14 ± 0.87 mm proud. The global angular deviation averaged 1.42 ± 1.53 degrees, with 95% confidence limits of 1.24 and 1.60 degrees. The crown of the actual placed implant showed an average deviation from the plan of 1.10 ± 0.69 mm and the apex of the placed implant showed a deviation of 1.12 ± 0.69 mm. Haptic robotic guidance showed greater precision than freehand, static computer-guided, and dynamic computer-guided implant placement. Conclusions: This large clinical series of 273 implants shows a high accuracy of implant placement compared to the published accuracy for angular deviations for any technology, as well as demonstrating statistically greater precision. Long-term clinical studies are necessary to establish the true effect of increased accuracy on clinical outcomes. Using haptic robotic guidance provides accurate implant placement while allowing additional benefits compared to computer-guided surgery, namely full visualization of the surgical field and the ability to change the plan intraoperatively. [ABSTRACT FROM AUTHOR]

Tooth autotransplantation is an effective treatment to replace missing teeth. Digital planning can facilitate successful autotransplantation. Guiding templates are highly recommended when performing cases in healed ridges in the posterior area to reduce excessive bone loss and increase the chances of fitting the donor tooth in the new socket. This case report highlights the use of 3D planning tools and fully guided drilling templates for successful tooth autotransplantation in the posterior area. Two tooth autotransplantations were performed in a 51-year-old patient using mandibular third molars to replace hopeless mandibular first and second molars. Root canal treatments were carried out before the surgeries, and different alveoloplasty techniques were used in each recipient area. The prosthetic phase was carried out after 9 months. Both teeth were asymptomatic, functional, and exhibited no signs of resorption or apical radiolucency and showed complete regeneration of the periodontal apparatus at the 2-year follow-up. [ABSTRACT FROM AUTHOR]

The use of conventional scan bodies (SBs) with an intraoral scanner (IOS) to capture the position of a complete arch of dental implants has proven to be challenging. The literature is unclear about the accuracy of intraoral scanning techniques using SBs that are connected vertically to multiunit abutments (MUAs) for numerous adjacent implants in the same arch. Recently, there has been a paradigm shift from vertical SBs to horizontal SBs, which are positioned perpendicular to the long axis of the MUAs. Most IOSs available today can capture these horizontal SBs, called scan gauges (SGs), with better accuracy and consequently acquire the position of multiple adjacent implants using an effective scan path, thus reducing stitching and the number of images. The key to implementing this novel technology is to strategically arrange the SGs to optimize horizontal overlap of multiple adjacent SGs without touching each other. By superimposing two high-resolution intraoral scans of the SGs, an artificial intelligence (AI) algorithm is employed to produce a calibrated digital best-fit model on which a passive complete-arch prosthesis can be designed and fabricated. The advantages and disadvantages of SBs and SGs are discussed, and a case report using a digital workflow is presented. [ABSTRACT FROM AUTHOR]

Purpose: To compare the 3D accuracy of three scanning strategies and conventional impressions using an edentulous model with six implants. Materials and Methods: An edentulous maxillary master model was fabricated with six equigingival internal connection implants at 0 degrees of angulation. Ten conventional open-tray splinted implant-level impressions were made and poured in stone. A master model and conventional casts were digitized with a reference scanner. Digital impressions were made by calibrated clinicians with a TRIOS 3 intraoral scanner ([IOS] 3Shape) according to three scanning strategies: DIG1 (occlusal-palatal-lingual), DIG2 (S-type motion from buccal to palatal), and DIG3 (scanning two half arches and connecting them at the midline). Each technique was repeated 10 times on the master model. Deviations from the STL datasets (N = 40) were compared to those of the reference master model using the Hexagon Metrology software system PC-DMIS CAD++. Linear distortions (dX, dY, dZ), global linear distortion (dR), and angular distortions (Absdθx, Absdθy) were calculated. Kruskal-Wallis test and mixed linear and logistic regression models were used to compare the original and binary distortion measures between the techniques. Results: The mean dR ranged from 91 μm (conventional method) to 183 μm (DIG1). The mean angular distortion ranged from 0.20 degrees (Absdθx for DIG2) to 0.69 degrees (Absdθy for DIG3). No scan pattern resulted in a more accurate reproduction in any of the measured parameters than the conventional impression method. There were significant differences between the methods for all distortion measures. Conclusions: No group reproduced the 3D position of the six-implant master model below the thresholds for both global linear and angular distortions. All the digital strategies tested were less accurate than the conventional open-tray splinted implant-level impression technique. [ABSTRACT FROM AUTHOR]

Currently, the incision design for periodontal and implant surgeries is mainly based on the surgeon's personal preference. The primary aim of this study is to review the intricate periodontal microvascular system and to illustrate the potential impact of commonly applied flap designs on the integrity of this system. A complete literature electronic search resulted in 37 relevant articles. The maxillary, facial, and lingual arteries supply the microvasculature system, including the supraperiosteal, intraligamental, and intraosseous arterioles. These arterioles have their own territories yet are extensively interconnected. The impact of common papilla management techniques are discussed, including tunneling; papilla base, incision, and preservation; and flap-releasing incisions. Flap design can impact reperfusion and blood inflow in the early healing phase, which eventually influences wound closure probability, healing speed, surgical predictability, tissue volume change, and postoperative morbidity. Future studies on the three-dimensional distribution of microvasculature and clinical impact of various flap designs on tissue reperfusion can lead to evidence-based incision selection and improved wound-healing outcomes. [ABSTRACT FROM AUTHOR]

In this position paper, the state of the art in immediate implant placement (IIP) at incisor-cuspid-premolar sites is described. The literature supports that the following prerequisites need to be simultaneously met for a predictable outcome: (1) there must be no acute infection; (2) there must be apical and palatal/lingual bone for implant anchorage; (3) the tooth must be inside the bone envelope; (4) the alveolar socket must have a favorable morphology (type I, IIa, IIb avoiding wide dehiscences); (5) there must be no midfacial recession; (6) the right implant must be selected; and (7) the surgeon needs to be experienced and skilled. A preoperative CBCT is required for IIP because multiple aforementioned prerequisites (2, 3, and 4) can only be assessed on the basis of 3D imaging. The final prerequisite relates to the importance of a perfect implant position, preferably leaving a horizontal gap of at least 2 mm between the implant shoulder and buccal bone wall. Guided surgery is preferred over free-hand surgery to accomplish this. Flapless surgery, socket grafting, connective tissue graft (CTG), and immediate provisionalization have been shown to contribute to hard and/or soft tissue stability. When the previously mentioned prerequisites are fulfilled, IIP may be considered over alternative treatment concepts (eg, early implant placement [EIP] and delayed implant placement [DIP]) based on time gain, minimal invasiveness, and similar outcomes in the literature. Given very strict selection criteria, clinicians should primarily screen patients for IIP before considering other treatment options with wider indications. [ABSTRACT FROM AUTHOR]

Purpose: To compare the linear and angular deviations of sites prepared for implants with the proposed 3D-printed sliding guide vs a 3D-printed conventional sleeveless static guide. Materials and Methods: This study consisted of two groups: a control group of 14 3D-printed conventional sleeveless static guides, and a test group of 37 3D-printed sliding guides. The guides were designed to drill 37 implant sites in each group. Linear and angular deviations were determined after scanning the drilled casts. Linear deviations were measured at the coronal and apical aspects of the drilled implant sites at 5-, 10-, 15-, and 20-mm distances. Results: There were no significant differences between the control and study groups regarding the coronal and 5-mm apical linear deviations. The angular and 10-, 15-, and 20-mm linear deviations of the 3D-printed sliding guide were significantly smaller than the control group. Conclusions: The proposed 3D-printed sliding guide could reduce the angular deviation of drilled implant sites from the planned positions, which is reflected in reducing the linear apical deviation of prepared implant sites longer than 5 mm. [ABSTRACT FROM AUTHOR]

Objectives: Low bone density and lack of adequate vertical bone dimension as a result of maxillary sinus pneumatization present some of the most problematic cases for endosseous implant applications in posterior maxillary regions that hinder prosthetic rehabilitation. The overall objectives of the study were to assess the histologic, histomorphometric, and radiologic evaluation of biopsies gathered from maxillary sinuses that were grafted with three different bovine bone particles (Bio-Oss, Cerabone, and Ti-Oss) and analyze the volume of the bone graft and the quantity of new bone formation. Method and materials: Thirty-six patients with < 4 mm of residual ridge height unilaterally in the posterior maxilla were equally divided into three groups, each of which received different bovine bone particles for maxillary sinus augmentation. Six months later, biopsies were harvested for histologic and histomorphometric evaluations. Volumetric changes in maxillary sinus augmentation were analyzed at 1-week and 6-month time-points following maxillary sinus augmentation surgery. Results: Histomorphometric and histologic analysis revealed a significant difference between the Ti-Oss group compared with the Bio-Oss and Cerabone groups (P=.011). In terms of residual graft particlesand soft tissue, there were no significant differences between groups. 3D volumetric reductions between 1-week (baseline) and 6-month time-points recorded significant graft volume reduction in all groups (P < .05). Significantly greater bone resorption and lower new-bone formation were manifested in the Ti-Oss group in comparison to the other groups. Conclusions: Within the limits of thisstudy, histologic and radiologic results indicated that Bio-Oss and Cerabone could be used efficiently in sinus augmentation procedures, while further prospective studies are needed to evaluate the Ti-Oss material in maxillary sinus augmentation. [ABSTRACT FROM AUTHOR]

A comprehensive 3D imaging analysis was conducted to investigate the corrosion process in reinforced concrete (RC) samples at various stages of the accelerated galvanostatic corrosion process. A state-of-the-art X-ray computed tomography (CT) scan technology was utilized to collect high-resolution 3D images of the specimen. The CT imaging was complemented and validated using a multi-faceted approach utilizing Scanning electron microscopy (SEM) and Raman spectrometry techniques. The distribution and evolution of voids, corrosion products, and cracks were investigated. A localized corrosion was observed that has some similarity to pitted corrosion but not as wide spread along the bar. The micro-scale imaging investigations revealed a gradual increase in the diameter of voids as the time of corrosion increased, especially after 8 days of accelerated corrosion process at which a significant decrease in small-sized voids (≤0.11 mm) accompanied by an increase in other void sizes was observed. At 10 and 12 days of accelerated corrosion process, the volume of larger-sized voids (≥0.35 mm) continued to increase, indicating a rapid corrosion progress and the formation of corrosion-induced cracks. In addition, a thorough X-ray CT analysis allowed us to differentiate between various categories of corrosion products. Notably, iron oxides and iron hydroxides were found to dominate the corrosion products. Understanding the composition and distribution of these corrosion products is essential as they play a significant role in the degradation and deterioration of the concrete structure. The coexistence of iron oxides and iron hydroxides in the region of corrosion products were confirmed using Raman spectroscopy analysis. The CT scan images captured the evolution of cracks at different time intervals, revealing a strong correlation between the initiation of cracks and the presence of corrosion products. Subsequently, during the cracking in the matrix, while the propagation of corrosion products within the matrix contributed to the expansion of cracks. SEM images and elemental analysis confirmed that these cracks were filled with corrosion products. [ABSTRACT FROM AUTHOR]

ABSTRACT Background and Aims Methods Results Conclusions Ultrasound imaging and shear wave elastography (SWE) can be used to noninvasively stage hepatopathologies and are widespread in clinical practice. These techniques have recently been adapted for small animal use in a novel 3D in vivo imaging system capable of high‐throughput automated scanning. Our goal was to evaluate the feasibility of using this imaging tool in the murine Western diet (WD) model, a highly translatable preclinical model of obesity, metabolic disease and liver fibrosis.Female C57BL/6 mice (N = 48) were placed on WD or chow diet and imaged longitudinally for a period of 48 weeks. Imaging consisted of 3D B‐mode and targeted SWE captures. Liver volume, liver echogenicity and liver stiffness were quantified from in vivo imaging data. A subset of mice was sacrificed at various timepoints (0, 12, 24 and 48 weeks) for histological workup. Correlation analysis was performed between in vivo imaging and histological measurements to determine level of agreement.Noninvasive imaging showed statistically significant increases in liver volume and echogenicity, but non‐significant increase in liver stiffness in the WD‐fed cohort, suggesting development of hepatomegaly and steatosis, but negligible fibrosis. Ex vivo analysis confirmed significant increases in liver weight, liver triglycerides and ALT, but limited increases in fibrosis corroborating noninvasive imaging results. Correlation analysis between imaging and histology demonstrated good agreement between liver volume/liver weight (R2 = 0.85) and echogenicity/triglycerides (R2 = 0.76).This study demonstrated that noninvasive ultrasound liver assessments are feasible in the WD mouse model and closely reflect the underlying pathological state of the animal. Automated ultrasound can serve as a high‐throughput noninvasive screening method for preclinical liver disease research and drug development. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel voxel-based 3D single object tracking (3D SOT) method called Voxel Pseudo Image Tracking (VPIT). VPIT is the first method that uses voxel pseudo images for 3D SOT. The input point cloud is structured by pillar-based voxelization, and the resulting pseudo image is used as an input to a 2D-like Siamese SOT method. The pseudo image is created in the Bird's-eye View (BEV) coordinates; and therefore, the objects in it have constant size. Thus, only the object rotation can change in the new coordinate system and not the object scale. For this reason, we replace multi-scale search with a multi-rotation search, where differently rotated search regions are compared against a single target representation to predict both position and rotation of the object. Experiments on KITTI [1] Tracking dataset show that VPIT is the fastest 3D SOT method and maintains competitive Success and Precision values. Application of a SOT method in a real-world scenario meets with limitations such as lower computational capabilities of embedded devices and a latency-unforgiving environment, where the method is forced to skip certain data frames if the inference speed is not high enough. We implement a real-time evaluation protocol and show that other methods lose most of their performance on embedded devices; while, VPIT maintains its ability to track the object. [ABSTRACT FROM AUTHOR]

Background: Respiratory compromise among ankylosing spondylitis (AS) patients is characterized by restrictive pulmonary function, leading to the need for a meticulous assessment of lung volume. Compared with conventional pulmonary function tests (PFTs), CT-based lung volume measurements have superior accuracy and are crucial for understanding functional limitations in AS. This study investigated the correlation between CT lung volume and PFT parameters in AS patients, with a focus on changes in CT parameters and lung volume in patients with compromised pulmonary function. Methods: A total of 79 AS patients were included, and their full-length radiographs, thoracic CT scans, and PFT data were analysed. Specialized software was used to estimate the total and lobar lung volumes from the CT scans. The relationship between lung volume and PFT results was examined, and a multiple linear regression model was constructed to determine the influence of radiographic and CT parameters on total lung volume (TLV). Patients were classified into normal or impaired pulmonary function groups based on PFT outcomes, thus facilitating comparative analyses of radiographic and CT parameters and lung volumes between these groups. Results: Among the 79 AS patients, 19 had normal function, 4 had mixed dysfunction, and 56 experienced restrictive dysfunction. PFT parameters, including FVC, FEV1, TLC, FEV1%, and TLC%, showed varying correlations with TLV and individual lobe volume. Patients with compromised pulmonary function exhibited more pronounced spinal kyphosis and experienced a decline in TLV. Multiple regression analysis revealed that lung height and horizontal and vertical lung diameters independently influenced TLV. Notably, a decrease in lung height was observed in patients with impaired pulmonary function, whereas the horizontal and vertical diameters of the lungs remained stable. Conclusions: In AS patients, TLV was found to be correlated with pulmonary function, particularly parameter such as FVC, FEV1, and TLC. A significant reduction in TLV was observed in those with impaired pulmonary function, with the primary contributing factor being a decrease in lung height. [ABSTRACT FROM AUTHOR]

We demonstrate a new tomographic imaging device for 2D cross-sectional and 3D volumetric images of the anterior eye segment. The optical system combines optical sectioning with a stereoscopic camera setup to determine the true spatial location of the ocular structures. Moreover, we propose a calibration procedure to estimate the triangulation function that links the stereo camera pixel indices with the eye-referenced 3D spatial coordinates. The proposed instrument will image the entire anterior chamber and contiguous structures, including the corneal limbus, sclera and eyelids. Furthermore, the system can obtain corneal topography. Finally, we studied the repeatability of the instrument and its agreement with a commercial Scheimpflug imaging tomographer in a group of healthy subjects. [ABSTRACT FROM AUTHOR]

Micro-CT imaging is a powerful tool for generating high-resolution, isotropic, three-dimensional datasets of whole, centimeter-scale model organisms. At histological resolutions, micro-CT can be used for whole-animal qualitative and quantitative characterization of tissue and organismal structure in health and disease. The small size, global freshwater distribution, wide range of cell size and structures of micron scale, and common use of Daphnia magna in toxicological and environmental studies make it an ideal model for demonstrating the potential power of micro-CT-enabled whole-organism phenotyping. This protocol details the steps involved in D. magna samples preparation for micro-CT, including euthanasia, fixation, staining, and resin embedding. Micro-CT reconstructions of samples imaged using synchrotron micro-CT reveal histological (microanatomic) features of organ systems, tissues, and cells in the context of the entire organism at sub-micron resolution and in 3D. The enabled "3D histology" and 3D renderings can be used for morphometric analyses across cells, tissues, and organ systems. [ABSTRACT FROM AUTHOR]

Background: Orthopedic surgeries often involve the insertion of bone screws for various fixation systems. The risk of postoperative screw loosening is usually assessed through experimental or finite element (FE) evaluations of the screw pull-out strength. FE simulations are based on either personalized complex but accurate heterogeneous modeling or non-personalized simple but relatively less accurate homogeneous modeling. This study aimed to develop and validate a novel personalized computed tomography (CT)-based homogeneous FE simulation approach to predict the pull-out force of cancellous bone screws. Methods: Twenty FE simulations of L1-L5 vertebral screw pull-out tests were conducted, i.e., 10 heterogeneous and 10 homogenous models. Screws were inserted into the lower-middle region of vertebrae. In our novel homogeneous model, the region around approximately twice the diameter of the screw was used as a bone material reference volume. Subsequently, the overall material property of this region was homogeneously attributed to the entire vertebra, and pull-out simulations were conducted. Results: The mean error of the predicted pull-out forces by our novel homogenous simulations was ~ 7.9% with respect to our heterogeneous model. When solely the cancellous bone was involved during the pull-out process (i.e., for L1, L2, and L3 vertebral bodies whose cortical bone in the inferior region is thin), the novel homogenous model yielded small mean error of < 6.0%. This error, however, increased to ~ 11% when the screw got involved to the cortical bone (for L4 and L5 vertebrae whose cortical bone in the inferior region is thick). Conclusion: The proposed personalized CT-based homogenous model was highly accurate in estimating the pull-out force especially when only the cancellous bone was involved with the screw. [ABSTRACT FROM AUTHOR]

Ex vivo x‐ray angiography provides high‐resolution, three‐dimensional information on vascular phenotypes down to the level of capillaries. Sample preparation for ex vivo angiography starts with the removal of blood from the vascular system, followed by perfusion with an x‐ray dense contrast agent mixed with a carrier such as gelatine or a polymer. Subsequently, the vascular micro‐architecture of harvested organs is imaged in the intact fixed organ. In the present study, we present novel microscopic dual‐energy CT (microDECT) imaging protocols that allow to visualise and analyse microvasculature in situ with reference to the morphology of hard and soft tissue. We show that the spectral contrast of µAngiofil and Micropaque barium sulphate in perfused specimens allows for the effective separation of vasculature from mineralised skeletal tissues. Furthermore, we demonstrate the counterstaining of perfused specimens using established x‐ray dense contrast agents to depict blood vessels together with the morphology of soft tissue. Phosphotungstic acid (PTA) is used as a counterstain that shows excellent spectral contrast in both µAngiofil and Micropaque barium sulphate–perfused specimens. A novel Sorensen‐buffered PTA protocol is introduced as a counterstain for µAngiofil specimens, as the polyurethane polymer is susceptible to artefacts when using conventional staining solutions. Finally, we demonstrate that counterstained samples can be automatically processed into three separate image channels (skeletal tissue, vasculature and stained soft tissue), which offers multiple new options for data analysis. The presented microDECT workflows are suited as tools to screen and quantify microvasculature and can be implemented in various correlative imaging pipelines to target regions of interest for downstream light microscopic investigation. [ABSTRACT FROM AUTHOR]

Background: There are differences in the research results regarding which edge design of occlusal veneers can achieve the best long-term success rate as a relatively new fixed prosthesis restoration method. Further research is needed. The three-dimensional finite element method was used to conduct stress analysis on occlusal veneers of maxillary first permanent molars with different thicknesses and margin preparation designs. The aim of this study was to provide mechanical research evidence and a reference for exploring standardized clinical protocols for the design of occlusal veneer restorations of maxillary first molars. Method: A 3Shape (Intraoral Scanner) was used to scan the maxillary first molar teeth in vitro, after which 3D printing was carried out. Three different edge designs were applied to identical teeth: straight-beveled finishing line(SFL), chamfer finishing line(CFL), and standard cuspal inclination(SCI). Preparation was carried out with a thickness of 0.5 mm. Using the surface deformation feature, the occlusal veneer was thickened to 0.5 mm and 1.0 mm, and periodontal ligaments were added. They were then placed into the upper and lower jaws and dental arches. Finite element analysis was performed after applying bite force dispersion to the loading area on the mandible following dynamic contact. Results: (1) As the thickness increased, the maximum Von Mises stress in the occlusal veneers SFL and CFL also increased, while the SCI exhibited the opposite trend. (2). The trend of the maximum Von Mises stress in the adhesive layer decrease gradually with increasing thickness of the occlusal veneer. The stresses of the SFL and CFL is concentrated primarily at the edge position below the functional cusp, resulting in relatively low adhesive stress. However, in the SCI group, the maximum stress at the edge of the adhesive layer exceeds the maximum shear strength of commonly used adhesives. Conclusions: Under the experimental conditions, the mechanical properties of the maximum Von Mises stress in the SFL, CFL, and SCI occlusal veneers meet clinical needs. Incorporating the minimally invasive concept of tooth preservation, a thickness of 1.0 mm are optimal for glass ceramic occlusal veneers on maxillary first molars. Highlights: This experiment combined finite element analysis with traditional mechanical experiments and prepared models with identical shapes using 3D printing. This approach avoided experimental errors caused by variations in the shape of natural teeth among individuals, uneven bonding agent thickness, and different design morphologies of the occlusal surface. Additionally, the roughness of the prepared surface more closely resembled the true roughness encountered in clinical settings. By incorporating periodontal ligament (PDL) hyperelastic materials into jaw dentition, a more realistic nonlinear analysis of periodontal ligament deformation was conducted. Dynamic contact results, which differed from the static loading stresses typically used in finite element analyses, were obtained by applying biting forces and simulating the movement of biting. Daily chewing is not merely a collision between highly elastic model materials and restorations or teeth, as in extraoral experiments. Instead, it simulates the mechanical properties of the daily foods of primates, using materials that closely match these properties. [ABSTRACT FROM AUTHOR]

Traditional dental prosthetics require a significant amount of work, labor, and time. To simplify the process, a method to convert teeth scan images, scanned using an intraoral scanner, into 3D images for design was developed. Furthermore, several studies have used deep learning to automate dental prosthetic processes. Tooth images are required to train deep learning models, but they are difficult to use in research because they contain personal patient information. Therefore, we propose a method for generating virtual tooth images using image-to-image translation (pix2pix) and contextual reconstruction fill (CR-Fill). Various virtual images can be generated using pix2pix, and the images are used as training images for CR-Fill to compare the real image with the virtual image to ensure that the teeth are well-shaped and meaningful. The experimental results demonstrate that the images generated by the proposed method are similar to actual images. In addition, only using virtual images as training data did not perform well; however, using both real and virtual images as training data yielded nearly identical results to using only real images as training data. [ABSTRACT FROM AUTHOR]

Micro-computed tomography (CT) of ancient Chinese glass dragonfly eye beads has enabled detailed exploration of their internal structures, contributing to our understanding of their manufacture. Segmentation of these CT images is essential but challenging due to variation in grayscale values and the presence of bubbles. This study introduces a U-Net-based model called EBV-SegNet, which enables efficient and accurate segmentation and visualization of these beads. We developed, trained, and tested the model using a dataset comprising four typical Shampula dragonfly eye beads, and the results demonstrated high-precision segmentation and precise delineation of the beads' complex structures. These segmented data were further analyzed using the Visualization Toolkit for advanced volume rendering and reconstruction. Our application of EBV-SegNet to Shampula beads suggests the likelihood of two distinct manufacturing techniques, underscoring the potential of the model for enhancing the analysis of cultural artifacts using three-dimensional visualization and deep learning. [ABSTRACT FROM AUTHOR]

Background: Previous studies have evaluated the safety and efficacy of transcutaneous auricular vagus nerve stimulation (taVNS) for the treatment of Parkinson's disease (PD). However, the mechanism underlying the effect of taVNS on PD remains to be elucidated. This study aimed to investigate the immediate effects of taVNS in PD patients. Methods: This crossover self-controlled study included 50 PD patients. Each patient underwent three sessions of resting-state functional magnetic resonance imaging (rs-fMRI) under three conditions: real taVNS, sham taVNS, and no taVNS intervention. We analyzed whole-brain amplitude of low-frequency fluctuations (ALFF) from preprocessed fMRI data across different intervention conditions. ALFF values in altered brain regions were correlated with clinical symptoms in PD patients. Results: Forty-seven participants completed the study and were included in the final analysis. Real taVNS was associated with a widespread decrease in ALFF in the right hemisphere, including the superior parietal lobule, precentral gyrus, postcentral gyrus, middle occipital gyrus, and cuneus (voxel p < 0.001, GRF corrected). The ALFF value in the right superior parietal lobule during real taVNS was negatively correlated with the Unified Parkinson's Disease Rating Scale Part III (r = −0.417, p = 0.004, Bonferroni corrected). Conclusion: TaVNS could immediately modulate the functional activity of brain regions involved in superior parietal lobule, precentral gyrus, postcentral gyrus, middle occipital gyrus, and cuneus. These findings offer preliminary insights into the mechanism of taVNS in treating PD and bolster confidence in its long-term therapeutic potential. TaVNS appears to reduce ALFF values in specific brain regions, suggesting a potential modulation mechanism for treating PD. [ABSTRACT FROM AUTHOR]

Confocal Laser Scanning Microscopy (CLSM) is an advanced imaging technique used in various fields. It offers several advantages over conventional microscopy due to its high resolution and ability to collect three-dimensional data using optical sectioning. While the resolution in confocal microscopy is comparatively lower than that of electron microscopy, it has effectively bridged the gap between these two imaging techniques. In the medical field, CLSM has a wide range of applications, including the diagnosis and treatment of corneal diseases, the study of biofilms and the diagnosis of various types of cancers, as well as the viral pathogenic cycle, including that of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). CLSM is also beneficial in food technology. The present review synthesises the current knowledge on CLSM, encompassing its applications, technological advancements and limitations. A comprehensive search of relevant databases identified studies and articles published by September 2023. The findings highlight CLSM's versatility, with applications ranging from cell biology to materials science, while also addressing technical challenges and future prospects. [ABSTRACT FROM AUTHOR]

ProjectAnatomy combines tangible objects with video projections that show the anatomy of the human forearm intended for learning through its eye-catching appearance. The prototype was shown to three target groups: non-experts, trainee medical students, and anatomy experts to provide qualitative and quantitative feedback. The study and observation of the users in the first two groups were carried out 'in the wild' where the users would come in contact with this type of visualisation to collect data on how it should be adjusted to their needs. The results have shown that the non-experts find it most helpful in learning anatomy, contrary to the experts who find it less useful yet very interesting and see its educational potential. The trainee medical students scored it the lowest; however, they would find it helpful to complement dissection classes. We conclude that this visual installation could be used in science centres and, when enriched with more details, for beginning medical students. Our study contributes specifically to the field of physical visualisation using 3D printed objects combined with projections that can be adjusted to the level of detail suitable for the target audience. [ABSTRACT FROM AUTHOR]

Integral imaging (InIm) 3D displays provide realistic 3D images with comfortable viewing experiences. However, existing approaches struggle to achieve high spatial resolution reproduction without relying on temporal or spatial multiplexing methods, which increases system complexity. Although precise control approaches for voxel formation have been explored to address this challenge, the existing methods lack systematic analysis theories for identifying the key factors affecting spatial resolution. In this study, a novel analysis framework is proposed that uses a point spread function (PSF) to characterize voxel formation. An analytical model based on the obtained PSF is established to achieve an aliasing‐free display. This framework identifies optimization directions for improving the spatial resolution, specifically by reducing the Gaussian blur caused by wavefront aberration in the lens unit. A targeted optimization of a compound lens array is conducted to achieve precise control of voxel formation. In these experiments, an InIm 3D display system prototype that substantially outperforms conventional InIm 3D displays is developed. The prototype achieves a 74.6% reduction in the system PSF and a 29.85% reduction in voxel size, enabling aliasing‐free voxels and a 2.82 times higher resolution in the InIm 3D display. [ABSTRACT FROM AUTHOR]

Background: A prominent anterior tibial tuberosity (or tibial tubercle) can be seen in ongoing Osgood–Schlatter disease (OSD) in teenagers or as a sequela of OSD in adults. Current radiological methods do not provide a true anatomical assessment of the tibial tuberosity; therefore, we proposed and developed a Magnetic Resonance Imaging (MRI)-based method for measuring the anterior tibial tuberosity index, aiming to deal with the current lack of effective techniques for accurately assessing these particular morphologic features. Methods: A retrospective study included 47 knees with tibial tuberosity measurements on both true sagittal MPR images of 3D proton density (PD)-weighted MRI sequences and lateral knee radiographs. The same landmarks were followed and the anterior tibial tuberosity index (ATTI) was measured. Results: The comparison of the results obtained by the two methods demonstrates that our method is reliable and reproducible with substantial inter- and intra-observer agreement. The intraclass correlation coefficient was 0.9250 (95% CI: 0.8654 to 0.9582), indicating excellent reliability between the two methods. A strong positive correlation was also identified, with a correlation coefficient of r = 0.8746 (95% CI: 0.7845 to 0.9286, p < 0.0001) between the two methods. No significant deviation from linearity was observed by analyzing the linear model validity using the cusum test (p = 0.62). Conclusions: Based on these results, we encourage the use of 3D PD-weighted MRI sequences for the measurement of the anterior tibial tuberosity on MRI in order to avoid unnecessary exposure to ionizing radiation and potentially obtain a more accurate measurement. Future larger studies should also explore the benefit of utilizing 3D sequences over 2D lateral projections to minimize measuring bias. [ABSTRACT FROM AUTHOR]

Objectives. To evaluate the accuracy and reproducibility of measurements obtained using the Bellus3D Face Application on a mobile smartphone by comparing them to direct measurements on pre-marked and blank face scans. Materials and Methods. Twenty-five healthy young adults (six males and nineteen females; age range 20–30 years) were included in this prospective cross-sectional study, with the only exclusion criterion being the presence of significant facial hair interfering with the placement and visualization of landmarks. Image acquisitions were performed using an iPhone XR with the Bellus3D FaceApp face scanning application, an iOS application for smartphones. Ten single midfacial and five paired bilateral landmarks were defined and marked. Two face scans were performed on each patient, both on blank and marked faces, and distances were measured directly with calipers and digitally. Results. The random error values were 1.0 mm and 0.4 mm for the manual point placement and measurements and virtual point placement on blank faces, respectively. The two methods used (the direct method and acquisition on faces with landmarks) demonstrate relatively similar reliability (ICC > 0.8); however, a paired t-test showed that the differences between several measurements were statistically significant (p < 0.05). Regardless of the method used, there was a systematic error for various values that included the nose and mouth (p < 0.05). The measurements demonstrating the most significant differences between the methods were those that included the tip of the nose, with the mean differences being −4.4–3.3 mm. The measurements of the distances that estimate face "depth" showed the greatest consistency irrespective of the tested method (p > 0.05 and ICC > 0.8). Conclusions. The use of the Bellus3D FaceApp is precise and reproducible for certain areas of the face, but digital reconstruction errors prohibit, for the time being, the use of this technology in everyday clinical practice. The noted discrepancies were consistent and more prevalent for specific areas such as the tip of the nose. Further investigations are required to determine other sources of error and for other smartphone-based applications released for 3D face image acquisitions. [ABSTRACT FROM AUTHOR]

Due to their unique mechanical and thermal properties, polyurethane foams are widely used in multiple fields of applications, including cushioning, thermal insulation or biomedical engineering. However, the way polyurethane foams are usually manufactured ‐ via chemical foaming ‐ produces samples where blowing and gelling occur at the same time, resulting in a morphology control achieved by trial and error processes. Here, a novel strategy is introduced to build model homogeneous polyurethane foams of controlled density with millimetric bubbles from liquid templates. By producing a polyurethane foam via physical bubbling without a catalyst and gently depositing a secondary foam containing catalyst on the top of this first foam, it is possible to take advantage of drainage mechanisms to trigger the solidification of the bottom foam. The characterization of the samples performed by X‐ray microtomography allows to study quantitatively the structure of the final solid foam, at the global and at the local scale. Using the tomographic 3D images of the foam architectures, the superimposed foam technique introduced in this article is shown to be promising to produce foams with a good homogeneity along the vertical direction, with a density controlled by varying the concentration of catalyst in the secondary foam. [ABSTRACT FROM AUTHOR]

Background/Objectives: Digital mammography (DM) has long been the standard for breast cancer screening, while digital breast tomosynthesis (DBT) offers an advanced 3D imaging modality capable of generating 2D Synthetic Mammography (SM) images. Despite SM's potential to reduce radiation exposure, many clinics favor DM, with DBT and SM, due to its perceived diagnostic reliability. This study investigates whether radiologists can replace DM with SM in breast cancer screening and diagnosis or if both modalities are necessary. Methods: We retrospectively analyzed DM and SM images from 375 women aged 40–65 who underwent DM with DBT at King Khaled University Hospital from 2020–2022. Three radiologists evaluated the images using ACR BI-RADS, assessing diagnostic accuracy via the area under the receiver operating characteristic (ROC) curve (AUC). The agreement in cancer conspicuity, breast density, size, and calcifications were measured using weighted kappa (κ). Results: Among 57 confirmed cancer cases and 290 cancer-free cases, DM demonstrated higher sensitivity (82.5% vs. 78.9%) and diagnostic accuracy (AUC 0.800 vs. 0.783, p < 0.05) compared to SM. However, SM detected more suspicious calcifications in cancer cases (75.6% vs. 51.2%, p < 0.05). Agreement was fair for conspicuity (κ = 0.288) and calcifications (κ = 0.409), moderate for density (κ = 0.591), and poor for size (κ = 0.254). Conclusions: while SM demonstrates enhanced effectiveness in detecting microcalcifications, DM still proves superior in overall diagnostic accuracy and image clarity. Therefore, although SM offers certain advantages, it remains slightly inferior to DM and cannot yet replace DM in breast cancer screening. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate the diagnostic performance, image quality, and inter- and intra-observer agreement of the 3D T1 multi-echo fast field echo (mFFE) sequence in cervico-thoraco-lumbar vertebral fractures compared with conventional computed tomography (CT) as the gold standard. Methods: We conducted a prospective single-centre study including 29 patients who underwent spinal magnetic resonance imaging (MRI) at the surgeon's request, in addition to CT for vertebral fracture assessment and classification. A 3D T1 mFFE sequence was added to the standard MRI protocol. Consecutively, two readers analyzed the 3D mFFE sequence alone, the 3D mFFE sequence with the entire MRI protocol, including the STIR and T1 sequences, and, finally, the CT images in random order and 1 month apart. A standardized assessment was performed to determine the presence or absence of a fracture, its location, its classification according to the Genant and AO classifications for traumatic and osteoporotic fractures, respectively, the loss of height of the anterior and posterior walls of the vertebral body, and the presence of concomitant disco-ligamentous lesions. Contingency tables, intraclass correlation coefficients, and Cohen's kappa tests were used for statistical analysis. Results: A total of 25 fractures were recorded (48% cervical, 20% thoracic, and 32% lumbar), of which 52% were classified A, according to the AO classification system. The quality of the 3D mFFE image was good or excellent in 72% of cases. Inter-observer agreement was near perfect (0.81–1) for vertebral body height and for AO and Genant classifications for all modalities. Intra-observer agreement was strong-to-near perfect between CT and the 3D mFFE sequence. Regarding the diagnostic performance of the 3D mFFE sequence, the sensitivity was 0.9200 and 0.9600, the specificity was 0.9843 and 0.9895, and the accuracy was 0.9861 and 0.9769 for Readers 1 and 2, respectively. In addition, up to 40% of intervertebral disc lesions and 33% of ligamentous lesions were detected by the 3D mFFE sequence compared to CT, allowing four AO type A fractures to be reclassified as type B. Conclusions: The 3D mFFE sequence allows accurate diagnosis of vertebral fractures, with superiority over CT in detecting disco-ligamentous lesions and a more precise classification of fractures, which can prompt clinicians to adapt their management despite an image quality that still requires improvement in some cases. Key points: Vertebral fractures and disco-ligamentous lesions can be assessed using CT-like MRI sequences, with 3D T1 mFFE being superior to CT for the detection of disco-ligamentous lesions. CT-like images using the 3D T1 mFFE sequence improve the diagnostic accuracy of bone structures in MRI. [ABSTRACT FROM AUTHOR]

Simple Summary: Artificial intelligence, now one of the most promising frontiers of medicine, has a long and tumultuous history punctuated by successes and failures. One of its successes was its application to medical images. We reconstruct the timeline of the advancements in this field, from its origins in the 1940s before crossing medical images to early applications of machine learning to radiology, to the present era where artificial intelligence is revolutionizing radiology. Artificial intelligence (AI), the wide spectrum of technologies aiming to give machines or computers the ability to perform human-like cognitive functions, began in the 1940s with the first abstract models of intelligent machines. Soon after, in the 1950s and 1960s, machine learning algorithms such as neural networks and decision trees ignited significant enthusiasm. More recent advancements include the refinement of learning algorithms, the development of convolutional neural networks to efficiently analyze images, and methods to synthesize new images. This renewed enthusiasm was also due to the increase in computational power with graphical processing units and the availability of large digital databases to be mined by neural networks. AI soon began to be applied in medicine, first through expert systems designed to support the clinician's decision and later with neural networks for the detection, classification, or segmentation of malignant lesions in medical images. A recent prospective clinical trial demonstrated the non-inferiority of AI alone compared with a double reading by two radiologists on screening mammography. Natural language processing, recurrent neural networks, transformers, and generative models have both improved the capabilities of making an automated reading of medical images and moved AI to new domains, including the text analysis of electronic health records, image self-labeling, and self-reporting. The availability of open-source and free libraries, as well as powerful computing resources, has greatly facilitated the adoption of deep learning by researchers and clinicians. Key concerns surrounding AI in healthcare include the need for clinical trials to demonstrate efficacy, the perception of AI tools as 'black boxes' that require greater interpretability and explainability, and ethical issues related to ensuring fairness and trustworthiness in AI systems. Thanks to its versatility and impressive results, AI is one of the most promising resources for frontier research and applications in medicine, in particular for oncological applications. [ABSTRACT FROM AUTHOR]

Simple Summary: While tumor cell invasion beyond the surgically resectable "margin" of glioblastoma is thought to be associated with nearly 100% of recurrences and poor survival, no reliable methods exist for mapping the location of invading tumor cells within the human brain. Building on prior work demonstrating the ability of Q-space magnetic resonance imaging (QSI) to highlight structural alterations in tissue architecture, we hypothesized that using this imaging method to construct tumor-associated tractography might identify tumor-specific structures that underlie cellular invasion. Our results demonstrate that such tractography patterns can be observed in a tumor-specific manner, and provide preliminary evidence that those patterns may colocalize with invading tumor cells, and metrics derived from them may be associated with patient survival time. Background: The invasion of glioblastoma cells beyond the visible tumor margin depicted by conventional neuroimaging is believed to mediate recurrence and predict poor survival. Radiomic biomarkers that are associated with the direction and extent of tumor infiltration are, however, non-existent. Methods: Patients from a single center with newly diagnosed glioblastoma (n = 7) underwent preoperative Q-space magnetic resonance imaging (QSI; 3T, 64 gradient directions, b = 1000 s/mm2) between 2018 and 2019. Tumors were manually segmented, and patterns of inter-voxel coherence spatially intersecting each segmentation were generated to represent tumor-associated tractography. One patient additionally underwent regional biopsy of diffusion tract- versus non-tract-associated tissue during tumor resection for RNA sequencing. Imaging data from this cohort were compared with a historical cohort of n = 66 glioblastoma patients who underwent similar QSI scans. Associations of tractography-derived metrics with survival were assessed using t-tests, linear regression, and Kaplan–Meier statistics. Patient-derived glioblastoma xenograft (PDX) mice generated with the sub-hippocampal injection of human-derived glioblastoma stem cells (GSCs) were scanned under high-field conditions (QSI, 7T, 512 gradient directions), and tumor-associated tractography was compared with the 3D microscopic reconstruction of immunostained GSCs. Results: In the principal enrollment cohort of patients with glioblastoma, all cases displayed tractography patterns with tumor-intersecting tract bundles extending into brain parenchyma, a phenotype which was reproduced in PDX mice as well as in a larger comparison cohort of glioblastoma patients (n = 66), when applying similar methods. Reconstructed spatial patterns of GSCs in PDX mice closely mirrored tumor-associated tractography. On a Kaplan–Meier survival analysis of n = 66 patients, the calculated intra-tumoral mean diffusivity predicted the overall survival (p = 0.037), as did tractography-associated features including mean tract length (p = 0.039) and mean projecting tract length (p = 0.022). The RNA sequencing of human tissue samples (n = 13 tumor samples from a single patient) revealed the overexpression of transcripts which regulate cell motility in tract-associated samples. Conclusions: QSI discriminates tumor-specific patterns of inter-voxel coherence believed to represent white matter pathways which may be susceptible to glioblastoma invasion. These findings may lay the groundwork for future work on therapeutic targeting, patient stratification, and prognosis in glioblastoma. [ABSTRACT FROM AUTHOR]

Objective: The cortical bone trajectory (CBT) technology is an effective substitute for traditional pedicle screw (PS) technology. However, there is still controversy about the CBT screw technology placement strategy. The objective of this study was to simulate cortical screw placement with the help of three‐dimensional (3D) software, to discuss the differences in screws between genders and vertebral segments, and to explore a safer and more efficient strategy for cortical screw placement. Methods: Mimics Medical software was used to construct a 3D model of the lumbar spine, and the placement of CBT screws was simulated. The volume of each vertebral body from L1 to L5, the pedicle isthmus height (IH), the pedicle isthmus width (IW), and the sagittal vertebral distance (SAVD) were measured. The transverse distance (TD) and the longitudinal distance (LD) between the ideal starting point (SP) and the clinical SP (the intersection Q of the midline of the superior articular process and the horizontal line 1 mm below the transverse process) were measured. The cephalad angle (CA), lateral angle (LA), maximum screw diameter (MSD), maximum screw length (MSL) of each trajectory of the L1 to L5 vertebral bodies, and the percentage of the screw insertion depth (PSID) into the vertebral body were measured. Data were statistically analyzed using Student's t‐test, one‐way analysis of variance (ANOVA), and Tukey's test. Results: Vertebral anatomical parameters and CBT screw parameters differed between males and females. Female patients had lower IH, IW, SAVD, CA, LA, MSD, and MSL than males. IH was greatest in L1 (male, 17.81 mm; female, 16.12 mm) and the smallest in L5 (male, 14.11 mm; female, 13.05 mm). IW was smallest in L1 (male, 8.89 mm; female, 7.37 mm) and greatest in L5 (male, 16.59 mm; female, 15.43 mm). The MSD of males was smallest in L1 (6.05 mm) and greatest in L3 (7.06 mm); the MSD of females was smallest in L1 (5.13 mm) and greatest in L4 (6.64 mm). MSL was greatest at L3 (male, 33.63 mm; female, 32.28 mm) and smallest at L5 (male, 31.25 mm; female, 29.97 mm). CA was smallest in L1 (male, 22.80°; female, 21.92°) and greatest in L3 (male, 25.29°; female, 24.33°). LA was smallest in L1 (male 12.37°, female 11.27°) and greatest in L5 (male 13.56°, female 12.96°). Among the males, TD was smallest at L1 (−0.51 mm) and greatest at L5 (1.37 mm), while LD was greatest at L2 (3.46 mm) and smallest at L5 (2.40 mm). In females, TD was greatest at L1 (0.12 mm) and smallest at L3 (−0.51 mm), while LD was greatest at L1 (3.69 mm) and smallest at L5 (2.08 mm). In the overall sample, the incidence of SAVD and PSID gradually increased from L1 to L5. Conclusion: The optimal screw placement strategy for CBT screws varies significantly according to sex and vertebral body segments, particularly noting the specificity of screw placement at L5. The optimal screw placement strategy should be selected based on the patient's sex and segment characteristics before surgery to maximize the safety and accuracy of CBT screw placement. [ABSTRACT FROM AUTHOR]

Background: Both high body mass index (BMI) and anterior cruciate ligament reconstruction (ACLR) independently influence knee osteoarthritis risk. Preliminary evidence shows the combination of these risk factors leads to poorer recovery and altered biomechanical outcomes after ACLR, but few studies have directly evaluated early changes in cartilage health between normal-BMI and high-BMI groups in this population. Purpose: To evaluate ultrasound-based measures of cartilage strain and compositional changes (via echo-intensity [EI]) in response to an incline walking stress test between normal-BMI and high-BMI individuals with ACLR. A secondary evaluation was conducted of associations between habitual walking biomechanics (ie, ground-reaction forces, sagittal knee kinetics and kinematics) and cartilage strain and EI outcomes. Study Design: Controlled laboratory study. Methods: Gait biomechanics and femoral trochlear ultrasound analyses were evaluated in 64 participants with ACLR who had normal BMI (BMI < 27.0; n = 40) and high BMI (BMI ≥ 27.0; n = 24). Ultrasound images were collected bilaterally before and after an incline treadmill walk, and medial and lateral trochlear strain and EI changes pre-post exercise were used to compare BMI groups and limbs. Gait outcomes included ground-reaction forces, peak sagittal plane knee moments, angles, and excursions and were used to determine associations with cartilage outcomes in the entire cohort. Results: High-BMI individuals with ACLR exhibited greater medial trochlear cartilage strain in the ACLR limb compared with normal-BMI individuals (approximately 6%; P <.01). In those with high BMI, the ACLR limb exhibited greater medial trochlear strain relative to non-ACLR limbs (approximately 4%; P <.05), but between-limb differences were not observed in the normal-BMI group (P >.05). Medial trochlear EI changes were greater bilaterally in those with high BMI compared with normal-BMI ACLR counterparts (approximately 10%; P <.01). Last, individuals who walked with greater peak knee flexion angles exhibited less medial cartilage strain (Δ R 2 = 0.06; P =.025). Conclusion: The data suggested that high BMI affects cartilage functional properties after ACLR, whereas smaller knee flexion angles were associated with larger medial cartilage strain. Clinical Relevance: High-BMI individuals with ACLR may represent a subset of patients exhibiting earlier declines in cartilage functional integrity in response to loading, necessitating additional or more targeted interventions to mitigate disease development. [ABSTRACT FROM AUTHOR]

Geological samples are inherently multi‐scale. Understanding their bulk physical and chemical properties requires characterization down to the nano‐scale. A powerful technique to study the three‐dimensional microstructure is X‐ray tomography, but it lacks information about the chemistry of samples. To develop a methodology for measuring the multi‐scale 3D microstructure of geological samples, correlative X‐ray micro‐ and nanotomography were performed on two rocks followed by scanning electron microscopy with energy‐dispersive spectroscopy (SEM‐EDS) analysis. The study was performed in five steps: (i) micro X‐ray tomography was performed on rock sample cores, (ii) samples for nanotomography were prepared using laser milling, (iii) nanotomography was performed on the milled sub‐samples, (iv) samples were mounted and polished for SEM analysis and (v) SEM imaging and compositional mapping was performed on micro and nanotomography samples for complimentary information. Correlative study performed on samples of serpentine and basalt revealed multiscale 3D structures involving both solid mineral phases and pore networks. Significant differences in the volume fraction of pores and mineral phases were also observed dependent on the imaging spatial resolution employed. This highlights the necessity for the application of such a multiscale approach for the characterization of complex aggregates such as rocks. Information acquired from the chemical mapping of different phases was also helpful in segmentation of phases that did not exhibit significant contrast in X‐ray imaging. Adoption of the protocol used in this study can be broadly applied to 3D imaging studies being performed at the Advanced Light Source and other user facilities. [ABSTRACT FROM AUTHOR]

X‐ray multi‐projection imaging (XMPI) is an emerging experimental technique for the acquisition of rotation‐free, time‐resolved, volumetric information on stochastic processes. The technique is developed for high‐brilliance light‐source facilities, aiming to address known limitations of state‐of‐the‐art imaging methods in the acquisition of 4D sample information, linked to their need for sample rotation. XMPI relies on a beam‐splitting scheme, that illuminates a sample from multiple, angularly spaced viewpoints, and employs fast, indirect, X‐ray imaging detectors for the collection of the data. This approach enables studies of previously inaccessible phenomena of industrial and societal relevance such as fractures in solids, propagation of shock waves, laser‐based 3D printing, or even fast processes in the biological domain. In this work, we discuss in detail the beam‐splitting scheme of XMPI. More specifically, we explore the relevant properties of X‐ray splitter optics for their use in XMPI schemes, both at synchrotron insertion devices and XFEL facilities. Furthermore, we describe two distinct XMPI schemes, designed to faciliate large samples and complex sample environments. Finally, we present experimental proof of the feasibility of MHz‐rate XMPI at the European XFEL. This detailed overview aims to state the challenges and the potential of XMPI and act as a stepping stone for future development of the technique. [ABSTRACT FROM AUTHOR]

Introduction: The novel cryoballoon with 28 mm or 31 mm adjustable diameters, aims to achieve a wide antral pulmonary vein isolation (PVI). However, the distribution of antral lesions and their variations based on left atrial (LA) remodeling require further clarification. Methods: We evaluated 22 patients (67 [59.5–74.8] years, 19 males) who underwent PVI of atrial fibrillation (AF) (13 paroxysmal AF [PAF] and 9 non‐PAF) using size‐adjustable cryoballoons. LA electro‐anatomical mapping was performed post‐PVI with three‐dimensional mapping systems. We assessed the shapes of the LA and pulmonary veins (PVs) and the distribution of isolated areas (IAs), comparing the results between PAF and non‐PAF patients. Results: In the left PVs (LPVs), the distance between the PV orifice and IA edge (PVos‐IA) was larger on the roof and posterior segments (~15 mm) but relatively smaller on the anterior segment near the PV ridge (<10 mm). For the right PVs (RPVs), it was more extensive in the posterior segment (10–15 mm). Comparing PAF and non‐PAF, there were no significant differences in the PVos‐IA except for the right posterior‐carina segment, antrum IA (LPVs: 5.9 ± 1.6 vs. 5.8 ± 0.8 cm², p =.81; RPVs: 4.8 ± 2.3 vs. 4.8 ± 1.2 cm², p =.81), distances between the right and left IAs on the LA posterior wall (LAPW), and un‐isolated LAPW area (9.0 ± 4.9 vs. 9.9 ± 2.5 cm², p =.62). No individual PVIs were observed in either group. Two patients exhibited overlapping IAs on the roof, and one patient who underwent 31 mm balloon applications for all PVs exhibited an LAPW isolation. Conclusion: The size‐adjustable cryoballoon achieved a wide antral PVI even in non‐PAF patients. [ABSTRACT FROM AUTHOR]

We propose a rendering method that enables the perception of 3D images at precise positions independent of the interocular distance of the observer by combining stacked stereo display and depth‐fused 3D (DFD) display and confirm its effectiveness through evaluation experiments. The depth range that can be expressed in stereo displays causes discomfort in observers because of the discrepancy between vergence and accommodation. However, the depth perceived differs depending on the interocular distance of the observer, resulting in discontinuity of the 3D image. Therefore, we propose a rendering method for stacked stereo displays that is independent of the observer's interocular distance using DFD display. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) are bio-based nanoparticles that, under the right conditions, self-align into chiral nematic liquid crystals with a helical pitch. In this work, we exploit the inherent confocal effect of second-harmonic generation (SHG) microscopy to acquire highly resolved three-dimensional (3D) images of the chiral nematic phase of CNCs in a label-free manner. An in-depth analysis revealed a direct link between the observed variations in SHG intensity and the pitch. The highly contrasted 3D images provided unprecedented detail into liquid crystal's native structure. Local alignment, morphology, as well as the presence of defects are readily revealed, and a provisional framework relating the SHG response to the orientational distribution of CNC nanorods within the liquid crystal structure is presented. This paper illustrates the numerous benefits of using SHG microscopy for visualizing CNC chiral nematic systems directly in the suspension-liquid phase and paves the road for using SHG microscopy to characterize other types of aligned CNC structures, in wet and dry states. [ABSTRACT FROM AUTHOR]

Background: Precise positioning of the acetabular component during total hip replacement is the key to achieving optimal implant function and ensuring long-term patient comfort. However, different anatomical variations, degenerative changes, dysplasia, and other diseases make it difficult. In this study, we discuss a method based on the three-dimensional direction of the transverse ligament, predicting native acetabular anteversion with higher accuracy. Methods: Angular positions of the acetabulum and direction of the transverse ligament were automatically calculated from routine computed tomography data of 270 patients using a registration algorithm. The relationship between acetabular angles and ligament direction and their relationship with sex, age, and pelvic tilt were sought. These relationships were then modelled using multilinear regression. Results: Including the direction of the transverse ligament in the sagittal and transverse planes as a regressor in the multilinear model explained the variation in acetabular anteversion (R2 = 0.76 for men, R2 = 0.63 for women; standard deviation in prediction: men, 3.92° and women, 4.00°). Conclusions: The results indicate that the ligament was suitable as a guidance structure almost insensitive to the ligament in the sagittal and transverse planes must be considered. Estimation based on the direction in only 1 plane was not sufficiently accurate. The operative acetabular inclination was not correlated with the direction of the ligament. The correlations were higher in men than in women. [ABSTRACT FROM AUTHOR]