Three-dimensional Dynamic Imaging Research Articles

The Correlation Between Static and Dynamic Facial Asymmetry in Unilateral Cleft Lip and Palate.

Assess the relationship between static and dynamic facial asymmetry in unilateral cleft lip and palate during maximum smile. Retrospective cross-sectional study. Multidisciplinary dentofacial planning clinic. Thirty-one surgically managed non-syndromic unilateral cleft lip and palate patients between the ages of 13 to 17 years. Dynamic three-dimensional (3D) facial images (four-dimensional [4D]) throughout the course of a maximum smile were captured using video stereophotogrammetry at a rate of 60 frames per second, which generated 180 3D images/expression. A generic facial mesh containing more than 7000 vertices was superimposed onto the 3D facial images to quantify and track facial asymmetry throughout the captured sequence. Partial ordinary Procrustes analysis was utilized to calculate an asymmetry score at the rest position, maximum smile, and at the point of maximum mathematical asymmetry. The relationships between the asymmetry at rest and the asymmetry at the point of maximum smile (static 3D), and the maximum mathematical asymmetry (dynamic 4D) were evaluated. Asymmetry scores were higher at maximum smile than at rest. Maximum mathematical asymmetry was observed in most cases during the relaxation phase. Static asymmetry at rest and maximum smile was strongly correlated with the maximum mathematical asymmetry (r = 0.941, P < .001). Static 3D asymmetry at both rest and maximum smile are strongly correlated with dynamic 4D facial asymmetry. The use of 4D imaging, combined with generic mesh conformation and dense correspondence analysis, provides a valid objective measure of facial asymmetry.

Image quality in three-dimensional (3D) contrast-enhanced dynamic magnetic resonance imaging of the abdomen using deep learning denoising technique: intraindividual comparison between T1-weighted sequences with compressed sensing and with a modified Fast 3D mode wheel.

To assess the image quality of a modified Fast three-dimensional (Fast 3D) mode wheel with sequential data filling (mFast 3D wheel) combined with a deep learning denoising technique (Advanced Intelligent Clear-IQ Engine [AiCE]) in contrast-enhanced (CE) 3D dynamic magnetic resonance (MR) imaging of the abdomen during a single breath hold (BH) by intra-individual comparison with compressed sensing (CS) with AiCE. Forty-two patients who underwent multiphasic CE dynamic MRI obtained with both mFast 3D wheel using AiCE and CS using AiCE in the same patient were retrospectively included. The conspicuity, artifacts, image quality, signal intensity ratio (SIR), signal-to-noise ratio (SNR), contrast ratio (CR), and contrast enhancement ratio (CER) of the organs were compared between these 2 sequences. Conspicuity, artifacts, and overall image quality were significantly better in the mFast 3D wheel using AiCE than in the CS with AiCE (all p < 0.001). The SNR of the liver in CS with AiCE was significantly better than that in the mFast 3D wheel using AiCE (p < 0.01). There were no significant differences in the SIR, CR, and CER between the two sequences. A mFast 3D wheel using AiCE as a deep learning denoising technique improved the conspicuity of abdominal organs and intrahepatic structures and the overall image quality with sufficient contrast enhancement effects, making it feasible for BH 3D CE dynamic MR imaging of the abdomen.

Two optimized novel potential formulas and numerical algorithms for mtimes n cobweb and fan resistor networks

The research of resistive network will become the basis of many fields. At present, many exact potential formulas of some complex resistor networks have been obtained. Computer numerical simulation is the trend of computing, but written calculation will limit the time and scale. In this paper, the potential formulas of a mtimes n scale cobweb resistor network and fan resistor network are optimized. Chebyshev polynomial of the second class and the absolute value function are used to express the novel potential formulas of the resistor network, and described in detail the derivation process of the explicit formula. Considering the influence of parameters on the potential formulas, several idiosyncratic potential formulas are proposed, and the corresponding three-dimensional dynamic images are drawn. Two numerical algorithms of the computing potential are presented by using the mathematical model and DST-VI. Finally, the efficiency of calculating potential by different methods are compared. The advantages of new potential formulas and numerical algorithms by the calculation efficiency of the three methods are shown. The optimized potential formulas and the presented numerical algorithms provide a powerful tool for the field of science and engineering.

Controllable rogue waves in a compressible hyperelastic plate

In this paper, we investigate various rational solutions of a (2+1)-dimensional nonlinear equation with variable-coefficients which can describe the propagation of nonlinear waves in a compressible hyperelastic plate, and interestingly we find a new phenomenon in nonlinear hyperelastic mechanics—rogue waves. Based on the symmetry transformation and Hirota bilinear form, we obtain breather waves and rogue waves. And when we choose appropriate material parameters and transformation functions, we can control their directions of propagation. In addition, we present three new interaction solutions, i.e. the rogue waves keep moving from side to side between a pair of resonance stripe solitary waves. Finally, we analysis the dynamics characteristics and evolution behaviors of the obtained solutions by three-dimensional dynamic images. This paper exhibits the existence of rogue waves in nonlinear hyperelastic mechanics, and presents potential application value for control of rogue waves in elastic mechanics, fluid dynamics and other fields of nonlinear science.

Cardiac gated multidetector computed tomography (MDCT) to determine valvular leaflet thrombosis and leaflet restriction.

The evaluation of patients following aortic valve replacement has evolved, with multiple imaging modalities available that complement each other and permit better and prompt delineation of specific structural or functional valve complications. Multidetector computed tomography (MDCT) is one of the diagnostic modalities with significant technologic advancements that have made possible to evaluate high detail of the moving heart. The ability to deliver three-dimensional and multiplanar dynamic imaging with fine detail has demonstrated the technique is well suited to investigate valve complications. In this review article, we focus on some of the most contributing roles of MDCT in the diagnosis of complications associated with valvular pathology.

Classification of Alar Dynamic Aesthetic in an Asian Female Population: Experts or Automatic Algorithms?

To provide referenced classifications of alar dynamic aesthetics from both subjective and objective perspectives for determining proper surgical strategies in alarplasty. A total of 150 healthy Asian female participants were instructed to perform two standardized facial movements including a resting pose and a maximum smile while taking care not to show their teeth. The participants were recorded using a dynamic three-dimensional surface imaging system. Frames depicting the resting position and the alar maximum enlargement during the smile were exported separately for anthropometric analysis and classification. The alar dynamic aesthetic was assessed through measurement of the anthropomorphic changes comparing the resting and maximum smile statuses and then transformed into quantitative analysis through the algorithm [Formula: see text]. Subjective classification and evaluation of the subject cosmetic deficiencies and proposals for therapeutic interventions to improve the subjects' alar dynamic aesthetic were performed by three senior plastic surgeons through visualization of the resting and smiling images. The surgeons were asked to divide and classify the subjects into three groups (Class I, Class II and Class III) according to the surgeons' perceptions of degree of the subjects' deficiencies in alar dynamic aesthetic. The more deficiency there was in the aesthetic, the higher the class that the subject was assigned into. The surgeons were presented with the full set of images of the patients on two separate occasions each three months apart, to assess interobserver reliability. Clustering analysis, which is based on machine learning, was applied for objective classification of the images. According to the senior plastic surgeon experts' subjective classification, the subjects' alar flaring mobility was judged as follows: Class I (6.78 ± 3.84%), Class II (10.35 ± 4.18%), and Class III (18.68 ± 4.15%), while alar base mobility was judged as Class I (12.71 ± 7.57%), Class II (20.06 ± 10.06%), and Class III (30.86 ± 13.20%). By clustering analysis, alar flaring mobility was determined to be Class I (7.01 ± 3.51%), Class II (11.18 ± 4.76%), and Class III (12.72 ± 5.66%), while alar base mobility was Class I (9.07 ± 4.23%), Class II (21.88 ± 4.25%), and Class III (38.59 ± 7.08%). No statistical significance was found in the distribution and assignment of classes between the two methodologies. Classifications of alar dynamic aesthetics could arouse attention to facial dynamic aesthetics and provide referenced quantitative parameters for plastic surgeons to determine appropriate treatments for alarplasty. For patients with Class I mobility, treatments are not recommended, while minimally invasive treatments can be deemed to be optional for patients with Class II alar mobility to potentially improve alar dynamic aesthetics. For patients with Class III alar mobility, surgical treatments are strongly recommended as options. Combing subjective classification with automated algorithms can provide a novel perspective and improve reliability for facial aesthetic classification analysis. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Multi-scale band-limited illumination profilometry for robust three-dimensional surface imaging at video rate.

Dynamic three-dimensional (3D) surface imaging by phase-shifting fringe projection profilometry has been widely implemented in diverse applications. However, existing techniques fall short in simultaneously providing the robustness in solving spatially isolated 3D objects, the tolerance of large variation in surface reflectance, and the flexibility of tunable working distances with meter-square-level fields of view (FOVs) at video rate. In this work, we overcome these limitations by developing multi-scale band-limited illumination profilometry (MS-BLIP). Supported by the synergy of dual-level intensity projection, multi-frequency fringe projection, and an iterative method for distortion compensation, MS-BLIP can accurately discern spatially separated 3D objects with highly varying reflectance. MS-BLIP is demonstrated by dynamic 3D imaging of a translating engineered box and a rotating vase. With an FOV of up to 1.7 m × 1.1 m and a working distance of up to 2.8 m, MS-BLIP is applied to capturing full human-body movements at video rate.

Quantitative assessment of regional pulmonary perfusion using three-dimensional ultrafast dynamic contrast-enhanced magnetic resonance imaging: pilot study results in 10 patients

Background. Currently there is a high demand in reliable noninvasive diagnostic technique assessing the physiological parameters of the lungs. We are exploring the three-dimensional ultrafast MRI sequence as a novel diagnostic modality allowing the assessment of regional quantitative perfusion parameters in pulmonary tissue.&#x0D; Aim. To assess regional differences in quantitative pulmonary perfusion parameters in 10 volunteers with no evidence of interstitial lung disease by computed tomography, clinical, and laboratory data.&#x0D; Materials and methods. 10 volunteers with no signs of interstitial lung disease were examined by three-dimensional ultrafast dynamic contrast-enhanced MR imaging using 3D T1-weighted images. The values of pulmonary blood flow (PBF), mean transit time (MTT), and pulmonary blood volume (PBV) for the targeted regions of interest were calculated based on the dynamic image series. For calculations, arterial input function (AIF) was used, as well as the time-intensity curves.&#x0D; Results. The values of PBF, MTT, and PBV showed statistically significant differences between central and peripheral sections of lungs. Provided model can be implemented for quantitative assessment of regional pulmonary perfusion allows it to be used to determine the reliability of PBF, MTT and PBV values.&#x0D; Conclusions. Three-dimensional ultrafast MRI sequence is a novel diagnostic modality allowing the assessment of regional quantitative pulmonary perfusion parameters in pulmonary tissue, regardless of physiological features of blood supply mechanisms in different lung regions.

Scalp-Mounted Electrical Impedance Tomography of Cerebral Hemodynamics.

An Electrical Impedance Tomography (EIT) system has been developed for dynamic three-dimensional imaging of changes in conductivity distribution in the human head, using scalp-mounted electrodes. We attribute these images to changes in cerebral perfusion. At 100 frames per second (fps), voltage measurement is achieved with full-scale signal-to-noise ratio of 105 dB and common-mode rejection ratio > 90 dB. A novel nonlinear method is presented for 3-D imaging of the difference in conductivity distribution in the head, relative to a reference time. The method achieves much reduced modelling error. It successfully localizes conductivity inclusions in experimental and simulation tests, where previous methods fail. For > 50 human volunteers, the rheoencephalography (REG) waveform is observed in EIT voltage measurements for every volunteer, with peak-to-peak amplitudes up to approx. 50 μVrms. Images are presented of the change in conductivity distribution during the REG/cardiac cycle, at 50 fps, showing maximum local conductivity change of approx. 1% in grey/white matter. A total of 17 tests were performed during short (typically 5s) carotid artery occlusions on 5 volunteers, monitored by Transcranial Doppler ultrasound. From EIT measurements averaged over complete REG/cardiac cycles, 13 occlusion tests showed consistently decreased conductivity of cerebral regions on the occluded side, and increased conductivity on the opposite side. The maximum local conductivity change during occlusion was approx. 20%. The simplicity of the carotid artery intervention provides a striking validation of the scalp-mounted measurement system in imaging cerebral hemodynamics, and the REG images indicate its unique combination of sensitivity and temporal resolution.

Application of 3D Dynamic Image Technology in Industrial Products

Aiming at the problems of manual testing of industrial products, a measurement method of industrial products based on three-dimensional dynamic imaging technology is proposed. The products on the production line are dynamically photographed from different angles and within a certain period of time by using cameras. Then the obtained Image denoising processing and contour tracking based on chain code table and line segment table to obtain boundary information and regional information of each enclosed area of the image. Experimental tests show that the test accuracy of this method is 100%, which is suitable for real-time detection. Fully automated research on product testing provides the foundation.

The novel three-dimensional pulse images analyzed by dynamic L-cube polynomial model.

A dynamic L-cube polynomial is proposed to analyze dynamic three-dimensional pulse images (d3DPIs), as an extension of the previous static L-cube polynomial. In this paper, a weighted least squares (WLS) method is proposed to fit the amplitude C(t) of d3DPI at four physiological key points in addition to the best fit of L-cube polynomials to the measured normal and cold-pressor-test (CPT)-induced taut 3DPIs. Compared with other two fitting functions, C(t) of a dynamic L-cube polynomial can be well matched by the proposed WLS method with the least relative error at four physiological key points in one beat with statistical significance, in addition to the best fit of the measured 3DPIs. Therefore, a dynamic L-cube polynomial can reflect dynamic time characteristics of normal and CPT-induced hypertensive taut 3DPIs, which can be used as an evidence of hypertension diagnosis.

Current and future perspectives on functional molecular imaging in nephro-urology: theranostics on the horizon.

In recent years, a paradigm shift from single-photon-emitting radionuclide radiotracers toward positron-emission tomography (PET) radiotracers has occurred in nuclear oncology. Although PET-based molecular imaging of the kidneys is still in its infancy, such a trend has emerged in the field of functional renal radionuclide imaging. Potentially allowing for precise and thorough evaluation of renal radiotracer urodynamics, PET radionuclide imaging has numerous advantages including precise anatomical co-registration with CT images and dynamic three-dimensional imaging capability. In addition, relative to scintigraphic approaches, PET can allow for significantly reduced scan time enabling high-throughput in a busy PET practice and further reduces radiation exposure, which may have a clinical impact in pediatric populations. In recent years, multiple renal PET radiotracers labeled with 11C, 68Ga, and 18F have been utilized in clinical studies. Beyond providing a precise non-invasive read-out of renal function, such radiotracers may also be used to assess renal inflammation. This manuscript will provide an overview of renal molecular PET imaging and will highlight the transformation of conventional scintigraphy of the kidneys toward novel, high-resolution PET imaging for assessing renal function. In addition, future applications will be introduced, e.g. by transferring the concept of molecular image-guided diagnostics and therapy (theranostics) to the field of nephrology.

Dynamic three-dimensional imaging and digital volume correlation analysis to quantify shear bands in grus

The meso-deformation evolution in grus is crucial to the mechanical characteristics. Although the macroscopic deformation of grus has been widely studied, its physical meso-scale deformation and shear band evolution have not been well understood. In this paper, high energy X-ray computed tomography (CT) measurements and digital volume correlation (DVC) were performed on a grus sample under triaxial compression in order to quantify shear strain and shear bands in grus. Besides, a series of three-dimensional octahedral shear strain was obtained by DVC analysis. Furthermore, the corresponding evolution of the shear band, content, distribution characteristics and connectivity were investigated. The results show that the shear bands are formed at the stage where the axial strain is equal to 8%; generally, they are obliquely distributed as a whole and connected in an irregular flat strip shape; besides, the failure path may cause the grains to divert or branch due to the anisotropic distribution of grains. Moreover, the octahedral shear strain approximation obeys the χ2 distribution. There are at least two types of distribution of shear bands. Small-scale shear bands may be generated in different areas in the material at the initiation state, whereas the correlation and directionality between the variety of shear bands are slight; while at the shear failure stage and the subsequent stages, a close correlation is found between the shear bands, the direction consistency is significant.

Coordinate transformation of three-dimensional image in integral imaging system illuminated by a point light source

The point light source is an important kind of directional light source. By using directional illumination, the performances of the integral imaging system will be enhanced. In this paper, the coordinate transformation characteristics of integral imaging systems illuminated by a point light source have been explored in detail. By using a dynamic point light source such as a moving light emitting diode to illuminate the imaging system, the position and size of the rendered three-dimensional image can be transformed in real time without updating the elemental images, and the depth of field of the imaging system is doubled. The coordinates of the three-dimensional image are changed with the distance between the point light source and the micro-lens array. The optical mechanism of the three-dimensional dynamic imaging phenomenon is analyzed. The coordinate transformation rules of the three-dimensional image are deduced and verified by experiments. The phenomenon may find potential applications in interactively three-dimensional display or augmented reality system.

The importance of the laser pulse-ablator interaction dynamics prior to the ablation plasma phase in inertial confinement fusion studies.

This work presents studies which demonstrate the importance of the very early heating dynamics of the ablator long before the ablation plasma phase begins in laser driven inertial confinement fusion (ICF) studies. For the direct-drive fusion concept using lasers, the development of perturbations during the thermo-elasto-plastic (TEP) and melting phases of the interaction of the laser pulse with the ablator's surface may act as seeding to the subsequent growth of hydro-dynamic instabilities apparent during the acceleration phase of the interaction such as for instance the Rayleigh-Taylor and the Richtmyer-Meshkov, which strongly affect the implosion dynamics of the compression phase. The multiphysics-multiphase finite-element method (FEM) simulation results are experimentally validated by advanced three-dimensional whole-field dynamic imaging of the surface of the ablator allowing for a transverse to the surface spatial resolution of only approximately 1 nm. The study shows that the TEP and melting phases of the interaction are of crucial importance since transverse perturbations of the ablator's surface can reach tens of nanometres in amplitude within the TEP and melting phases. Such perturbations are of Rayleigh type and are transferred from the ablator to the substrate from the very first moments of the interaction. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 1)'.

Formation of Dynamic and Binocular Three-Dimensional Images in Protective Holograms with Zero Diffraction Order

Variants of implementing trackograms, one of the types of zero-order holograms, for the formation of protective features for non-expert verification of their authenticity are considered. The three-dimensional image in trackograms is formed by glares on the walls of toroidal surfaces-tracks that represent relief stripes with the recording material. Variations in the shape of tracks, their length, and the number of sections of different tracks at one point in the image can provide security features that are convenient for non-expert identification of holograms. Track sizes and depths are compatible with the technology of conventional embossed holograms. Photos of holograms forming images in white light are shown.

Dynamics of enhanced gas trapping applied to CO2 storage in the presence of oil using synchrotron X-ray micro tomography

During CO2 storage in depleted oil fields, under immiscible conditions, CO2 can be trapped in the pore space by capillary forces, providing safe storage over geological times - a phenomenon named capillary trapping. Synchrotron X-ray imaging was used to obtain dynamic three-dimensional images of the flow of the three phases involved in this process - brine, oil and gas (nitrogen) - at high pressure and temperature, inside the pore space of Ketton limestone. First, using continuous imaging of the porous medium during gas injection, performed after waterflooding, we observed chains of multiple displacements between the three phases, caused by the connectivity of the pore space. Then, brine was re-injected and double capillary trapping - gas trapping by oil and oil trapping by brine - was the dominant double displacement event. We computed pore occupancy, saturations, interfacial area, mean curvature and Euler characteristic to elucidate these double capillary trapping phenomena, which lead to a high residual gas saturation. Pore occupancy and saturation results show an enhancement of gas trapping in the presence of both oil and brine, which potentially makes CO2 storage in depleted oil reservoirs attractive, combining safe storage with enhanced oil recovery through immiscible gas injection. Mean curvature measurements were used to assess the capillary pressures between fluid pairs during double displacements and these confirmed the stability of the spreading oil layers observed, which facilitated double capillary trapping. Interfacial area and Euler characteristic increased, indicating lower oil and gas connectivity, due to the capillary trapping events.

Numerical simulation of novel concept 4D cardiac microtomography for small rodents based on all-optical Thomson scattering X-ray sources

Accurate dynamic three-dimensional (4D) imaging of the heart of small rodents is required for the preclinical study of cardiac biomechanics and their modification under pathological conditions, but technological challenges are met in laboratory practice due to the very small size and high pulse rate of the heart of mice and rats as compared to humans. In 4D X-ray microtomography (4D μCT), the achievable spatio-temporal resolution is hampered by limitations in conventional X-ray sources and detectors. Here, we propose a proof-of-principle 4D μCT platform, exploiting the unique spatial and temporal features of novel concept, all-optical X-ray sources based on Thomson scattering (TS). The main spatial and spectral properties of the photon source are investigated using a TS simulation code. The entire data acquisition workflow has been also simulated, using a novel 4D numerical phantom of a mouse chest with realistic intra- and inter-cycle motion. The image quality of a typical single 3D time frame has been studied using Monte Carlo simulations, taking into account the effects of the typical structure of the TS X-ray beam. Finally, we discuss the perspectives and shortcomings of the proposed platform.

Volumetric dynamic oxygen-enhanced MRI (OE-MRI): comparison with CT Brody score and lung function in cystic fibrosis patients.

To demonstrate, in patients with cystic fibrosis (CF), the correlation between three-dimensional dynamic oxygen-enhanced magnetic resonance imaging (OE-MRI) measurements and computed tomography Brody score (CF-CT) and lung function testing (LFT). Twenty-one patients (median age, 25 years; female, n = 8) with a range of CF lung disease and five healthy volunteers (median age, 31 years; female, n = 2) underwent OE-MRI performed on a 1.5-T MRI scanner. Coronal volumes were acquired while patients alternately breathed room air and 100% oxygen. Pre-oxygen T1 was measured. Dynamic series of T1-weighted volumes were then obtained while breathing oxygen. T1-parameter maps were generated and the following OE-MRI parameters were measured: oxygen uptake (ΔPO2max), wash-in time and wash-out time. High-resolution CT and LFT were performed. The relationship between CF-CT, LFT and OE-MRI parameters were evaluated using Pearson correlation for the whole lung and regionally. Mean CF-CT was 24.1±17.1. Mean ΔPO2max and mean wash-in as well as skewness of wash-out showed significant correlation with CF-CT (ΔPO2max: r = -0.741, p < 0.001; mean wash-in: r = 0.501, p = 0.017; skewness of wash-out: r = 0.597, p = 0.001). There was significant correlation for the whole lung and regionally between LFT parameters and OE-MR (ΔPO2max: r = 0.718, p < 0.001; wash-in: r = -0.576, p = 0.003; wash-out skewness: r = -0.552, p = 0.004). Functional lung imaging using OE-MRI has the capability to assess the severity of CF lung disease and shows a significant correlation with LFT and CF-CT. • Oxygen-enhanced MRI might play a future role in evaluation and follow-up of cystic fibrosis. • Heterogeneity of parameter maps reflects localised functional impairment in cystic fibrosis. • Avoidance of cumulative radiation burden in CF is feasible using OE-MRI.

高定位精度三维动态追踪成像系统研究及应用

高定位精度三维动态追踪成像系统研究及应用