Dimensional Image Reconstruction Research Articles

Three dimensional image reconstruction of neuroanatomical structures: methods for isolation of the cortex, ventricular system, hippocampus, and fornix.

Magnetic Resonance (MR) imaging allows volumetric quantification of a variety of neuroanatomical structures using two dimensional (2D) images as well as three-dimensional (3D) reconstruction of the brain and any of its constituent parts. Three-dimensional analysis permits integration of the neuroanatomical changes which occur in pathologic states, with the cognitive and behavioral changes elucidated through neuropsychological assessment. This paper describes uniform methods for 3D neuroanatomical isolation of the neocortex, ventricular system, and hippocampus in both normal and pathologic states. The 3D methods are described in detail using two different software programs, ANALYZE and IMAGE. Three-dimensional neuroanatomical reconstructions were carried out on a patient who sustained a very severe traumatic brain injury. The 3D image analysis in the patient with traumatic brain injury, revealed structural changes in frontal and temporal cortex, ventricular dilation, and hippocampal atropy. The neuropsychological impairments in this patient, were consistent with the observed neuroanatomical changes revealed on 3D image reconstruction. This technology permits precise determinations of the extent and severity of the neuroanatomical changes which follow neurological injury disease.

Histometry and three-dimensional image reconstruction of the lung in congenital diaphragmatic hernia

A small lung capacity, hypoplasia of the airway system, and abnormalities of the pulmonary artery system have been demonstrated as pathologic characteristics of congenital diaphragmatic hernia, but opinions have differed on the degree of hypoplasia of the acinus and terminal airspace. In this study, acinar size, mean wall thickness of the terminal airspace, an surface area of the terminal airspace were histometrically evaluated in four clinical cases. In addition, the pulmonary artery system was investigated by computerized three dimensional image reconstruction. Hypoplasia of the lung acinus and terminal airspace was observed in all four cases, and hypoplasia was more marked as lung capacity decreased. Thickening of the walls of pulmonary arterioles was confirmed, and previously undescribed abnormal branching of the pulmonary artery was recorded.

Left pulmonary artery sling: Diagnosis and delineation of associated tracheobronchial anomalies with MR

The left pulmonary artery sling anomaly (SLPA) has generated controversy about its diagnosis, imaging and management particularly with regard to associated tracheobronchial anomalies. Objective. To evaluate the role of MR imaging in defining airway and vascular relationships in SLPA. Retrospective review of the imaging and clinical records of three children with SLPA who underwent MRI including three dimensional image reconstruction. MR was compared and correlated with other imaging methods: plain chest radiographs (3); bronchoscopy (3); barium esophagram (1); echocardiography (2); cineangiography (2). MRI was vastly superior to other methods for clearly depicting airway and vascular anatomy and interrelationships. Good quality imaging and safe sedation was easily achieved in young infants. MR also provided accurate noninvasive evaluation of the reconstructed pulmonary artery and airway postoperatively. MR is capable of differentiating the two subtypes of SLPA. Specific delineation of vascular and airway anatomy and spatial relationships is essential for surgical management: reimplantation of LPA in type I and both LPA reimplantation and airway reconstruction in type II because of associated long segment airway stenosis.

Oblique section 3-D reconstruction from thin sectioned biological specimens

Three dimensional (3-D) image reconstruction of plastic embedded and sectioned tissue has become an important tool for imaging complex biological structures in situ. Most 3-D imaging methods combine multiple views of tilted specimens which leads to radiation damage and mass loss. On the other hand oblique section 3-D reconstruction (OSR) can produce a 3-D image from a single view because an oblique section through a 2- or 3-D periodic specimen contains 3-D information which can be folded into a 3-D image. The resolution achievable in an OSR depends on section thickness and is lowest in the direction perpendicular to the section plane. In OSR there is no missing cone or wedge in the 3-D image because of tilt angle restrictions, but finite section thickness limits the vertical resolution. Two OSR methodologies have been developed, one called Crystallographic Serial Section Reconstruction or CSSR, and another called Super Lattice Reconstruction or SLR.

Three dimensional image reconstruction in conventional and confocal microscopy

Three dimensional image reconstruction in conventional and confocal microscopy

Structures of bovine and human papillomaviruses. Analysis by cryoelectron microscopy and three-dimensional image reconstruction

The structures of bovine papillomavirus type 1 (BPV-1) and human papillomavirus type 1 (HPV-1) were determined at 2.5 nm resolution by cryoelectron microscopy and three dimensional image reconstruction techniques. As expected, the reconstructions showed that both viruses consist of a T = 7 icosahedral capsid (approximately 60 nm in diameter) which surrounds a nucleohistone core. The capsid morphologies of the two viruses are nearly indistinguishable. Each capsid consists of a shell layer (approximately 2 nm thick) of nearly continuous density from which capsomers project radially to a maximum height of approximately 5.8 nm. The five-coordinate (pentavalent) and six-coordinate (hexavalent) capsomers both exhibit distinct five-fold axial symmetry as was observed for SV40 and polyoma viruses. Thus, both genera (papilloma and polyoma) of the papovavirus family have now been shown to have the characteristic "all-pentamer" capsid construction. BPV-1 and HPV-1 capsomers consist of a thick (8.6 nm diameter) trunk that broadens distally to form a regular five-pointed, star-shaped head, and proximally to create the shell layer where capsomers associate. A cylindrical channel (approximately 2.8 nm diameter) extends along the axis of each capsomer from the interior of the virus to a point approximately half way to the capsomer surface. Computationally sectioned views of individual capsomers displayed at decreasing radii show that each of the five capsomer subunits (in both pentavalent and hexavalent capsomers) makes a pronounced (30 degrees) left-handed twist just above the outer surface of the capsid shell. Similar views of the reconstructions also clarify the morphology of intercapsomer contacts. For example, they show how hexavalent capsomers coordinate six neighboring capsomers despite the fact that they contain only five subunits. The system of intercapsomer contacts is indistinguishable in BPV-1 and HPV-1, but quite different from that reported for polyoma virus capsids assembled in vitro from the major capsid protein, VP1 (D. M. Salunke, D. L. D. Caspar, and R. L. Garcea. 1989. Biophys. J. 56:887-900). Thus, because both polyoma and papilloma viruses have all-pentamer capsids, it appears that intracapsomer subunit-subunit interactions which stabilize pentameric capsomers are better preserved evolutionarily than those involved in capsomer-capsomer contacts.

Analytical Self-Consistent Theory of Three Dimensional Image Reconstruction from Projections

Image reconstruction techniques have been widely applied to electron microscopy and computerized tomography. The classic algebraic reconstruction problem is to reconstruct the three dimensional (3D) objects from experimentally measured two dimensional (2D) projections. In literature, only approximate algorithm and iterative procedure have been investigated. Recently, an analytical self-consistent reconstruction method has been proposed by the author. A discrete/continuous object is given:whlie 2D projections are

Two–dimensional image–reconstruction method from holograms sampled by fresnel zone plates

AbstractThe hologram of a single‐point object is called a Fresnel zone plate (FZP), and the hologram of a general object is represented as a superposition of FZP's. Since a point image can be reconstructed from the FZP at a reasonable location, there can be considered an image reconstruction method based on FZP. This paper proposes the FZP sampled hologram and the corresponding two‐dimensional image reconstruction method. The FZP sampled hologram is sampled with small interval at the central part and large interval at the periphery. By multiplying the phase function with the one‐dimensional hologram and performing the Fourier transform, the two‐dimensional image distribution can be determined for the azimuth and range. By analyzing the point‐image distribution, it is seen that the azimuth resolution of 6 mrad is obtained for the millimeter wave frequency of 35 GHz and the hologram length of 25 cm. It is seen also from the distribution that there exist side peaks of −4.8 dB at an azimuth angle of ± 11 mrad apart from the peak. An experiment was made for the millimeter‐wave holography with a simple object, and a satisfactory agreement with the theory was observed.

Three dimensional image reconstruction and visualization methods in X-ray computerized tomography: Original French title: Méthodes de reconstruction et de visualisation d'images tridimensionnelles en tomographie numérique par rayons X

Three dimensional image reconstruction and visualization methods in X-ray computerized tomography: Original French title: Méthodes de reconstruction et de visualisation d'images tridimensionnelles en tomographie numérique par rayons X

Generalised correction functions for convolutional techniques in three-dimensional image reconstruction

Presents simple expressions for the correction functions for convolutional techniques in three dimensional image reconstruction. The intrinsic property involved in these techniques is clarified. It is shown that the introduction of the concept of the distribution is useful to derive the ideal or practical correction functions used in convolution methods. The ideal correction functions obtained are summarised. The concept of correction function defined as the distribution may be a starting point for deriving more advanced reconstruction schemes.

Three Dimensional Image Reconstruction from Electron Micrographs with Fourier Method

Three Dimensional Image Reconstruction from Electron Micrographs with Fourier Method

Axial Tomography and Three Dimensional Image Reconstruction

A number of existing cameras for Nuclear Medicine imaging of radio-isotope distributions give depth information about the distribution. These devices have in common that they provide tomographic images of the object, that is, that images of a given object plane have that plane in focus and all other object planes contribute an out-of-focus background superimposed on the in-focus image. We present here a method for three dimensional reconstruction of these axial tomographic images which removes the blurred off-plane activity from a number of transverse planes simultaneously. The method is applicable to a number of tomographic cameras, such as the multiple single-pinhole camera, the rotating slanted-hole collimator, the Anger focussing tomographic scanner, and the positron camera. The method can be implemented on a small computer having a disc system.

Three dimensional image reconstruction on an extended field—a fast, stable algorithm

WE describe an improved alogrithm (EFIRT) for solving iteratively the linear equations relating a three-dimensional density to a given set of its projections, when the unknown density is expressed as samples on a grid. The need to solve such equations arises in electron microscopy, medical radiography, radio and X-ray astronomy and other fields. The projection equations comprise a very large, sparse and often under-determined set. If the number of unknowns is not too large, the equations may be solved by a least squares procedure, using filtering to combat the ill-conditioning1. The number of unknowns is often too great for such a procedure to be computationally feasible and iterative techniques2,3 must be used. Alternatively the Fourier transform provides a stable and computationally efficient means of solution1. Sometimes use of the Fourier transform is not convenient; for example, if point rather than plane projections are given or if the projection data are weighted by a non-uniform but linear response of the measuring device. Such problems are much more readily expressed in terms of projection equations and the development of stable methods for their solution is therefore important.

Three Dimensional Image Reconstruction of Helical Structures

Three Dimensional Image Reconstruction of Helical Structures