Возможности прижизненной визуализации клеток крови при стрессе для оценки состояния организма

This study examined the action of anisosmotic media on the volume of nucleated erythrocytes isolated from Rana temporaria. Elevation of medium osmolarity from 100 to 345 mOsm resulted in attenuation of mean cell volume by more than 3-fold, estimated by hematocrit measurement. By contrast to this 'classic' erythrocyte volume evaluation technique, we did not observe any significant cell volume modulation by examining the 3D reconstruction of erythrocyte interference images obtained by laser interference microscopy. Comparative analysis of mean cell volume, phase height and cell area appraised by laser interference microscopy showed that the lack of visible alterations of phase image geometry was caused by sharp elevation of the average refractive index of the cytoplasm in shrunken cells. Thus, our results show for the first time that laser interference microscopy in combination with a direct method for cell volume measurement may be employed for estimation of the refractory index of intracellular milieu and for assessment of changes of physical chemical properties of the cytoplasm evoked by diverse stimuli including osmotic stress.

The effect of peptide prolyl-glycyl-proline (Pro-Gly-Pro) on morphometric parameters of mast cells upon their activation by compound 48/80 or synacten was investigated. Cell image, obtained by the method of laser interference microscopy (LIM), is a distribution of the optical path difference of light (OPD). It evaluates the changes of the individual components of cytoplasm (maxOPD) and the total distribution of OPD (“dry mass”). The changes of “dry mass” in cytoplasm correlate with the changes of the secreted histamine amount (−0.86). Preliminary incubation of mast cells with Pro-Gly-Pro (6 × 10−5 M) did not change the area, the state of the individual components of the cytoplasm (nucleus) and “dry mass” (histamine vesicles) in cells. The “dry mass” (histamine vesicles) and maxOPD decreased while the release of histamine increased upon the activation of mast cells by compound 48/80 (0.02 mg/mL). Preincubation of cells with Pro-Gly-Pro had no effect. Activation of cells by synacten (2 and 20 μM) led to the increase of the cell area and the reduction of maxOPD and “dry mass” (histamine vesicles). Preincubation of the cells with Pro-Gly-Pro prevented these changes. So, the protective effect of Pro-Gly-Pro was observed in the case of the activation of mast cells by synacten but not by compound 48/80.

Three-dimensional (3D) image reconstruction methods allied to spiral CT (SCT) or MR angiography (MRA) are used in clarifying the anatomy of complex aortic anatomy. Two patients with superior mediastinal masses suggestive of aneurysms of the anomalous right subclavian artery were examined. Both patients were examined using breath-hold SCT and one by breath-hold MRA. Three-dimensional images were reconstructed using a surface rendering technique for the SCT examinations and by a maximum intensity projection technique for MRA. Two cases of aneurysmal anomalous right subclavian artery were diagnosed by SCT with 3D image reconstruction. One case was also examined by MRA with 3D image reconstruction which confirmed the findings of SCT. The use of the 3D techniques clarified the complicated anatomy and avoided the need for angiography. Two cases are illustrated of 3D imaging of complicated aortic branch anatomy due to aneurysms of anomalous right subclavian artery. Image quality was good and no further imaging by more invasive techniques was required.

3D image reconstruction using light microscope modalities without exogenous contrast agents is proposed and investigated as an approach to produce 3D images of biological samples for live imaging applications. Multimodality and multispectral imaging, used in concert with this 3D optical sectioning approach is also proposed as a way to further produce contrast that could be specific to components in the sample. The methods avoid usage of contrast agents. Contrast agents, such as fluorescent or absorbing dyes, can be toxic to cells or alter cell behavior. Current modes of producing 3D image sets from a light microscope, such as 3D deconvolution algorithms and confocal microscopy generally require contrast agents. Zernike phase contrast (ZPC), transmitted light brightfield (TLB), darkfield microscopy and others can produce contrast without dyes. Some of these modalities have not previously benefitted from 3D image reconstruction algorithms, however. The 3D image reconstruction algorithm is based on an underlying physical model of scattering potential, expressed as the sample’s 3D absorption and phase quantities. The algorithm is based upon optimizing an objective function - the I-divergence - while solving for the 3D absorption and phase quantities. Unlike typical deconvolution algorithms, each microscope modality, such as ZPC or TLB, produces two output image sets instead of one. Contrast in the displayed image and 3D renderings is further enabled by treating the multispectral/multimodal data as a feature set in a mathematical formulation that uses the principal component method of statistics.

ABSTRACTA three-dimensional (3D) image reconstruction method for the spinning target based on the radar network is proposed in this letter and the design concept is sourced from the similarity of the two-dimensional (2D) imaging result with the target’s mapping on the imaging plane. The proposed method has the capacity to generate 3D image of the spinning target by reconstructing the scattering distribution in 3D Cartesian space. Firstly, the inverse Radon transform is applied to obtain the imaging result of the spinning target and the mapping formulas for mapping the air points onto the 2D image plane are derived. In addition, the radar network 3D image reconstruction model for the spinning target is constructed and the corresponding algorithm for solving the reconstruction model is proposed. Finally, some experiment results are given to verify the effectiveness of the proposed method.

To assess the value of three-dimensional (3D) image reconstructions of two-dimensional (2D) data from contiguous non-overlapping slices in the diagnosis of spinal trauma, 21 patients with a total of 36 injured vertebrae and 4 normal controls were examined. Forty plain films in two planes, 40 axial CT scans with multiplanar reformatted (MPR) 2D reconstructions and 40 sets of 3D images (surface rendering technique) were independently evaluated by four readers. The final diagnosis was defined after a panel review of clinical, surgical and imaging findings on all modalities. The 3D image reconstructions were not as accurate as axial CT with MPR 2D reconstructions in the diagnosis of vertebral body (n = 20) and posterior element fractures (n = 35). Dislocation (n = 3) was equally well detected by all imaging modalities. Narrowing of the spinal canal (n = 17) was best assessed by either MPR 2D CT or 3D images. A rotational component was diagnosed more accurately by 3D images, followed by 2D CT and plain films. Thus, 3D images combined with MPR 2D CT reconstructions are an important adjunct for an accurate diagnosis of spinal trauma, especially when a rotational component is suspected.

Three-dimensional reconstruction of medical images plays a vital role in clinical medicine and medical research. It serves as a powerful tool to help doctors analyze multiple 2D medical images in a 3D perspective. The developed 3D model offers a faster and accurate approach in clinical diagnosis and therapy. Before, the development of 3D reconstruction programs it has always been a challenge to visualize in a 3D perspective but with the advent of powerful computing and graphics processing, medical imaging equipment development is on the rise. The advancement of 3D image reconstruction is not only due to the innovative hardware, but also because of the increase in open-source platforms or libraries, such as visualization toolkit (VTK), that assist on its development to provide an information visualization framework and advanced 3D modeling techniques. VTK is an object-oriented 3D graphics software program that is free to obtain and used both for open- and closed-source applications such as 3D computer graphics, image processing, and visualization. In medical imaging, data from ultrasound systems, magnetic resonance imaging (MRI), and computed tomography (CT) scans can be managed in VTK. Different algorithms of image processing such as color mapping, image re-slicing or resampling, iso-contouring, thresholding, and other algorithms can be utilized to make volume images from the data. Subsequently, data presentation is simplified with the data reconstruction through the use of supplemental software for analysis. VTK library contains a large number of filters, which are multi-threaded to facilitate parallel processing and interpretation. In this paper, recent technologies on the application of VTK for 3D reconstruction of biomedical images will be presented. Moreover, current methodologies will be discussed to clearly understand the different integral steps needed in image data conversion.

This paper is about 3D image reconstruction from a limited set of computed tomography (CT) projections. We focus on configurations with very limited angle of view and on applications in which the image to be reconstructed is composed of one or several localized objects laying in a known background. We propose an original method based on the detection of the localized object voxels and on a sparse modeling of the image. Reconstruction is done by computing the maximum a posteriori estimator of the image parameters. To implement image reconstruction, we adopt a multigrid strategy in which coarse-to-fine resoluted images are successively reconstructed. This strategy provides detection of localized object voxels as well as accurate initial solutions at each resolution level. Each optimization stage is carried out by using an iterative deterministic descent algorithm. We propose a convergent single site update algorithm which consists of successive constrained optimizations with respect to one voxel at a time. We show the performance of the multigrid method on simulated data corresponding to a set of limited angle cone-beam projections of a synthetic image. The results are accurate, while both memory storage and numerical time of computation are dramatically reduced compared with the monogrid method.

3D or multi-dimensional medical image reconstruction is attracting more and more attention in modern era. Rapid volumetric image reconstruction is of paramount importance to clinicians for prompt diagnosis and analysis of complex tissue alternations. However, due to a high demand on computation for either the analytical or iterative image reconstruction algorithms, it is almost impossible to meet the requirement of real-time reconstruction. On the other hand, with high computing capability and broad banding characteristic, recently multi-core processors provide a new possibility and hopeful start for some of the most computation-demanding applications, such as medical imaging, digital media and entertainment equipment. This study aims to parallelize an analytical 3D CT image reconstruction algorithm, the so-called FDK method, and to implement it on an existing multi-core platform system, towards a real-time 3D medical image reconstruction. In this paper, the parallelization of the 3D image reconstruction algorithm, the coding optimizations and a comparative result of run time savings are described.

The productivity of single-particle cryo-EM as a structure determination method has rapidly increased as many novel biological structures are being elucidated. The ultimate result of the cryo-EM experiment is an atomic model that should faithfully represent the computed image reconstruction. Although the principal approach of atomic model building and refinement from maps resembles that of the X-ray crystallographic methods, there are important differences due to the unique properties resulting from the 3D image reconstructions. In this review, we discuss the practiced work-flow from the cryo-EM image reconstruction to the atomic model. We give an overview of (i) resolution determination methods in cryo-EM including local and directional resolution variation, (ii) cryo-EM map contrast optimization including complementary map types that can help in identifying ambiguous density features, (iii) atomic model building and (iv) refinement in various resolution regimes including (v) their validation and (vi) discuss differences between X-ray and cryo-EM maps. Based on the methods originally developed for X-ray crystallography, the path from 3D image reconstruction to atomic coordinates has become an integral and important part of the cryo-EM structure determination work-flow that routinely delivers atomic models.

To establish a 3D ultrasound imaging system based on pulse-triggered image acquisition using the linear probe on the VerasonicsTM vantage 128 platform and evaluate its performance in scanning standard phantom and human carotid artery. The 3D ultrasound imaging system included 3 modules for probe motion control, image acquisition and storage, and 3D image reconstruction and display. To improve the precision of image acquisition, we used fixed frequency pulses to control the external trigger function combined with mechanical scanning. Voxel-based 3D reconstruction was used for image reconstruction and display. The user interface was designed to allow direct operations of the platform. We carried out scanning tests of standard ultrasound phantom and human carotid artery to evaluate the performance of this imaging system. We successfully constructed a 3D ultrasound imaging system based on pulse-triggered image acquisition. The results of standard phantom and human carotid scanning tests showed that each module of the system was fully functional. The self-designed user interface of this ultrasound imaging system allowed full control of the system functions for original image acquisition, 3D image reconstruction, and display of cross-sections in 3 different views. This 3D ultrasound imaging system achieves high-quality 3D ultrasound imaging and provides the basis for further study and clinical application of 3D ultrasound imaging.

Methods of 3D reconstruction of medical images mainly included surface and volume reconstruction at present. In the experiment of 3D ultrasound reconstruction for spine of people, the result using volume reconstruction was unsatisfactory because of the ultrasound images' characteristic. So, we brought forward a method which was based on contour line to reconstruct 3D surface of spine. In this paper, we collected spinal ultrasound images using 3D freehand ultrasound firstly; next, tracing spinal contour line of each ultrasound images manually; finally, we used these contour lines to reconstruct spinal surface. The result showed that spinal surface reconstruction based on 2D contour line was close to real spinal surface, it could give physicians a better help in diagnosis of the spine.

Substrate characterization of the right ventricle in repaired tetralogy of Fallot using late enhancement cardiac magnetic resonance.

The problem of 3D reconstruction of medical images is very challenging due to the disadvantages of less texture and serious speckle noise. In this paper, we propose a medical image 3D reconstruction framework based on transfer learning and Structure-from-Motion. Unlike some existing methods, which need special hardware devices, or be effective for a particular modal of images, our unified framework does not depend on any special equipment and can be applied to diverse modalities of medical images, such as ultrasonic image, computed tomography (CT) etc. Its contribution covers three aspects: First, it uses Structure-From-Motion(SFM) to estimate the camera structure and pose of consecutive frames end-to-end, which is suitable for clinical auxiliary diagnosis. Second, strong and robust photogrammetry knowledge, including depth, the camera structure and pose, can be pre-learned from the natural images with the richer texture, and then, are transferred to the medical images learning. Besides, Med-3D is proposed, a GAN model based on self-supervised learning framework, in the generator, the spatial coplanar characteristics to constrain the cloud points reconstructed from a single captured frame or adjacent frames are considered for learning more precise features. Experimental results on the medical data of ultrasound images, and CT in the open clinical library, demonstrate that our method can reconstruct geometric structures from 2D slices and has excellent accuracy in terms of reconstruction effects.

Remote display and interaction of 3D reconstruction of medical images has been achieved utilizing VTK (the Visualization Toolkit) and HTML5. Aiming at the problem that the network coordination of the medical 3D reconstruction platforms are generally unsatisfactory, the feasibility of achieving multi-frames-based remote interaction of 3D reconstruction of medical images using Canvas and WebSocket in HTML5 has been discussed and verified by experiments. Furthermore, a method to display 3D images on pure Web client based on B/S (Browser/Server) framework has been put forward. The 3D reconstruction system with the application of this method has been proved to be effective in displaying and interacting on both PC and mobile platform with almost real-time effects. This feasible method has certain practical application in remote medical assistance.