3-D Imaging

Aim: To assess the degree of facial symmetry in patients suffering from unilateral cleft lip, alveolus and palate (UCLAP) by determining differences between the cleft and the non-cleft hemifaces from 3D surface data. Patients and methods: In twenty-two 10-year-old UCLAP patients, who had the lip repaired using the Tennison-Randall technique and did not undergo further revisional surgery, differences were determined between landmarks, surface areas of the upper lip vermilion and nostrils and virtual volumes of midface, nose and upper lip for cleft and non-cleft sides, separately, after having established a plane of symmetry calculated from optical 3D facial surface data. Results: Statistically significant differences could be found between cleft and non-cleft sides for the nasal landmarks G lat , G sup and La med , the nostril angle and the virtual volume of the nose (p Glat ¼ 0.011, p Gsup o0.0005, p Lamed ¼ 0.002, p nostril angle ¼ 0.036 and p nose volume o0.0005, resp.). Conclusion: Analysis of 3D data shows that complete nasal symmetry is difficult to achieve with Tennison-Randall's lip repair without revisional surgery. Further trials on larger populations of patients will allow a more comprehensive and consistent analysis of the consequence of different methods for cp repair in order to identify the techniques with the best outcome in terms of facial symmetry. r 2006 European Association for Cranio-Maxillofacial Surgery Keywords: facial volume; optical 3D imaging; plane of symmetry; 3D cephalometry; unilateral cleft lip and palate (UCLP)

We propose a new synthesis method for the hologram of 3D objects using incoherent multiple orthographic view images. The 3D objects are captured and their multiple orthographic view images are generated from the captured image. Each orthographic view image is numerically overridden by the plane wave propagating in the direction of the corresponding view angle and integrated to form a point in the hologram plane. By repeating this process for all orthographic view images, we can generate the Fourier hologram of the 3D objects.

New Technologies in Radiation Oncology provides an excellent overview of recent technologic developments in the field of radiation oncology. This book is intended for physicians and medical physicists who are working in radiation oncology and those just entering the field. It encompasses a broad range of new technologies in radiation therapy-from image acquisition and processing to treatment planning to therapy-and helps the reader grasp the basic ideas of each new technology. If the reader wants more information than the book provides, each chapter includes a wealth of references for learning about a particular subject in detail.

In recent years great interest has been posed in imaging techniques like X-ray computed microtomography which in a nondestructive way produce three-dimensional (3D) images of the internal structure of, e.g. porous media. A major challenge lies in the quantitative analysis of the resulting images that allows a more comprehensive and objective characterization of the sample under investigation. A software able to handle and process large 3D image datasets with common hardware is therefore necessary in order to extract morphological and textural information directly from the images. In the present paper the Pore3D software library developed by the SYRMEP research group of the Elettra Synchrotron Light Laboratory in Trieste (Italy) is presented. The library consists of several state-of-the-art functions and procedures for performing filtering, segmentation and quantitative analysis of 3D images. The current status of the project and some applications are here reported.

In order to construct a 3D model from a collection of 2D images of an object, an energy function is defined between the object's images and corresponding images of an articulated mesh in three dimensions. Repeated adjustment of the mesh to minimize the energy function results in a mesh that produces images which closely approximate the input images, that is to say that under the appropriate conditions it realizes a preconceived object. It has implications for model building, reverse engineering and computer vision. Minimization of the energy function is a multivariate problem of large scale with many local minima. We give an approach for solving this problem. For certain restricted, but useful applications, intuitive solutions to the minimization are consistently obtained. $

In this paper, we present a fully automatic, fast and accurate deformable registration technique. This technique deals with free-form deformation. It minimizes an energy functional that combines both similarity and smoothness measures. By using calculus of variations, the minimization problem was represented as a set of nonlinear elliptic partial differential equations (PDEs). A Gauss-Seidel finite difference scheme is used to iteratively solve the PDE. The registration is refined by a multi-resolution approach. The whole process is fully automatic. It takes less than 3 min to register two three-dimensional (3D) image sets of size 256 × 256 × 61 using a single 933 MHz personal computer. Extensive experiments are presented. These experiments include simulations, phantom studies and clinical image studies. Experimental results show that our model and algorithm are suited for registration of temporal images of a deformable body. The registration of inspiration and expiration phases of the lung images shows that the method is able to deal with large deformations. When applied to the daily CT images of a prostate patient, the results show that registration based on iterative refinement of displacement field is appropriate to describe the local deformations in the prostate and the rectum. Similarity measures improved significantly after the registration. The target application of this paper is for radiotherapy treatment planning and evaluation that incorporates internal organ deformation throughout the course of radiation therapy. The registration method could also be equally applied in diagnostic radiology.

An investigation to localise facial landmarks from 3D images is presented, without using any assumption concerning facial pose. This paper introduces new surface descriptors, which are derived from either unstructured face data, or a radial basis function (RBF) model of the facial surface. Two new variants of feature descriptors are described, generally named as point - triplet descriptors because they require three vertices to be computed. The first is related to the classical depth map feature, which is referred to as weighted - interpolated depth map. The second variant of descriptors are derived from an implicit RBF model, they are referred to as surface RBF signature (SRS) features. Both variants of descriptors are able to encode surface information within a triangular region defined by a point - triplet into a surface signature, which could be useful not only for 3D face processing but also within a number of graph based retrieval applications. These descriptors are embedded into a system designed to localise the nose - tip and two inner - eye corners. Landmark localisation performance is reported by computing errors of estimated landmark locations against our respective ground --truth data from the Face Recognition Grand Challenge (FRGC) database.

This paper describes the use of a 550 (25x22) element 2MHz 2D piezoelectric composite array in immersion mode to image an aluminum test block containing a collection of artificial defects. The defects included a 1mm diameter side-drilled hole, a collection of 1mm slot defects with varying degrees of skew to the normal and a flat bottomed hole. The data collection was carried out using the full matrix capture; a scanning procedure was developed to allow the operation of the large element count array through a conventional 64-channel phased array controller. A 3D TFM algorithm capable of imaging in a dual media environment was implemented in MATLAB for the offline processing the raw scan data. This algorithm facilitates the creation of 3D images of defects while accounting for refraction effects at material boundaries. In each of the test samples interrogated the defects, and their spatial position, are readily identified using TFM. Defect directional information has been characterized using VTFM for defect exhibiting angles up to and including 45 o of skew.

Page 1. Advanced pixel design for infrared 3D LADAR imaging Fabrice Guellec, Michaël Tchagaspanian Eric de Borniol, Pierre Castelein, André Perez, Johan Rothman CEA Leti – MINATEC, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France ABSTRACT ...

The International Rosetta Mission is set for a rendezvous with Comet 67 P/Churyumov-Gerasimenko in 2014. On its 10 year journey to the comet, the spacecraft will also perform a fly-by of the two asteroids Stein and Lutetia in 2008 and 2010, respectively. The mission goal is to study the origin of comets, the relationship between cometary and interstellar material and its implications with regard to the origin of the Solar System. Measurements will be performed that shed light into the development of cometary activity and the processes in the surface layer of the nucleus and the inner coma. The Micro-Imaging Dust Analysis System (MIDAS) instrument is an essential element of Rosetta's scientific payload. It will provide 3D images and statistical parameters of pristine cometary particles in the nm-μm range from Comet 67P/Churyumov-Gerasimenko. According to cometary dust models and experience gained from the Giotto and Vega missions to 1P/Halley, there appears to be an abundance of particles in this size range, which also covers the building blocks of pristine interplanetary dust particles. The dust collector of MIDAS will point at the comet and collect particles drifting outwards from the nucleus surface. MIDAS is based on an Atomic Force Microscope (AFM), a type of scanning microprobe able to image small structures in 3D. AFM images provide morphological and statistical information on the dust population, including texture, shape, size and flux. Although the AFM uses proven laboratory technology, MIDAS is its first such application in space. This paper describes the scientific objectives and background, the technical implementation and the capabilities of MIDAS as they stand after the commissioning of the flight instrument, and the implications for cometary measurements.

The reliable detection of the three-dimensional position of arbitrary objects in a scene is a key capability of most animals and one of the most important tasks in machine vision. Today's preferred technical solution is optical time-of-flight (TOF) range imaging, due to its simplicity, its distance resolution, its large and adaptable measurement range, as well as the absence of shadowing problems. In order significantly to extend the application areas of TOF 3-D cameras, in particular for outdoor use, we show how their performance can be improved in all relevant respects: Background light suppression is improved by an order of magnitude by the minimum charge transfer method. Multicamera operation is achieved by a binary pseudo-noise modulation/demodulation technique. This method also avoids all practical ambiguity problems typically encountered with harmonic modulation. Higher temporal demodulation resolution becomes possible with a pixel structure employing lateral electric fields. We have realized such pixels with a commercially available CCD/CMOS process, and our measurement results confirm that gigahertz demodulation imaging is possible. The practicality of all theoretical concepts is demonstrated with a miniaturized TOF 3-D camera platform whose LED array light source is modulated at a typical rate of 20 MHz. Our work contributes, therefore, to opening up new application domains of the soaring optical TOF range imaging techniques.

a b s t r a c t As technologies evolve, there have been high demands for the three-dimensional (3D) shape measurement techniques to posses the following combined technical features: high accuracy, fast speed, easy implementation, capability of measuring multiple objects as well as measuring complex shapes. Generally, the existing techniques can satisfy some of the requirements, but not all of them. This paper presents four practical considerations in fringe projection profilometry (FPP) based 3D shape measurements, along with simple but robust solutions, including gamma correction of digital projection, arbitrary setup of system components, phase unwrapping with multi-frequency fringes, and system calibration with a least-squares inverse approach. The validity and practicability of the FPPbased 3D shape measurement technique using the four corresponding technical approaches have been verified by experiments. The presented technique is capable of satisfying the various critical demands in enormous scientific and engineering applications.

Problem: High resolution, non-contrast imaging of both cerebral veins and arteries by use of gradient echo T2 star weighted angiography (SWAN) is a new method for susceptibility-weighted imaging with short acquisition times. We assessed the potential of this sequence for the depiction of both cerebral veins and arteries. Methods: 15 healthy volunteers were included in the study. MRI was performed on a 3 T MR scanner using the following sequences: (1) a 3D multi-echo gradient echo T2 star weighted angiography (SWAN), (2) an arterial 3D TOF MR angiography and (3) a venous 2D TOF.

At present, fracture risk prediction in the individual patient relies chiefly on bone mineral density (BMD) measurements. However, many lines of evidence indicate that the decreased bone strength characteristic of osteoporosis is dependent not only on BMD, but also on other factors, most notably bone microarchitecture. Here, we review available tools for characterizing trabecular microarchitecture (in terms of morphology, topology, and texture) and for obtaining 2D and 3D images (using radiography, computed tomography, and magnetic resonance imaging). Bone microarchitecture imaging is a noninvasive method that may improve fracture risk prediction in the individual patient, shed light on the pathophysiology of osteoporosis, and help to monitor the effects of treatments. Among the various methods available to date, magnetic resonance imaging has the advantage of involving no radiation exposure, although its limited availability restricts its usefulness for studying vast populations. Regardless of the methods selected to assess bone microarchitecture, there is a need for validated standardized parameters capable of improving fracture risk prediction in longitudinal studies.

Purpose/Objective(s): CBCT registration to a reference image is one of the emerging tools used for prostate localization. This preliminary study compares fiducial marker co-registration to two methods of CBCT image registration utilizing Varian On-Board Imaging System TM (OBI) and in-house automatic fusion software. Materials/Methods: Seventy CBCT scans from two localized prostate cancer patients were used for this study. Both patients were implanted with three 1.2x3 mm soft tissue markers. Each patient was educated regarding a bowel regimen to facilitate an empty rectum prior to simulation and daily treatment. For daily treatments, patients were initially aligned to skin marks. On-line automatic image fusion between CBCT and simulation CT (Sim-CT) was performed using OBI version 1.3. Offsets were recorded in three translational degrees of freedom. Prior to treatment, fiducial marker co-registration was performed using two KV-orthogonal images and offsets were recorded and applied to treatment couch, defining the treatment position. Inter-fiducial distances (n= 450) were measured and recorded to check for seed migration. In an offline manner, automatic in-house registration, utilizing the uphill simplex, gradient correlation and mutual information similarity measures, was performed between Sim-CT and CBCT using the prostate as the region of interest. Fiducial marker data, considered the control, was compared to the two CBCT image registration methods. Mismatch between fiducial marker and OBI (Fd-OBI) and mismatch between fiducial marker and in-house fusion (Fd-house) was measured. Mismatch in the LR, AP, CC directions was reported and percentage of observations falling between 1 and 7 mm between the two registration methods was tabulated. Results: Inter-fiducial distances showed minimal seed migration with mean of <1±0.7 mm. Comparing the two methods of registration, Fd-house showed a mean mismatch of 1.0± 0.65, 1.0±0.96 and 1±1.07 mm in the LR, AP, and CC directions respectively. Comparable data was observed for the Fd-OBI data with mean of 1.0±0.74, 2.0±1.28, and 2.0±1.69 mm in the LR, AP, and CC directions respectively. Examining the percentage of mismatch observations (n= 414) the following data was observed: Conclusions: While the technical aspects of fiducial marker co-registration are attractive, invasiveness and seed migration can be noted as potential drawbacks. The phenomenon of seed migration was not observed in our study justifying the use of fiducial marker as a good control. Our in house automatic fusion software in conjunction with CBCT images showed a superior correlation to the fiducial markers and can offer an attractive noninvasive tool for improving prostate localization.

Three-dimensional (3D) ultrasound (US) is increasingly being introduced in the clinic, both for diagnostics and image guidance. Although dedicated 3D US probes exist, 3D US can also be acquired with the still frequently used two-dimensional (2D) US probes. Obtaining 3D volumes with 2D US probes is a two-step process. First, a positioning sensor must be attached to the probe; second, a reconstruction of a 3D volume can be performed into a regular voxel grid. Various algorithms have been used for performing 3D reconstruction based on 2D images. Up till now, a complete overview of the algorithms, the way they work and their benefits and drawbacks due to various applications has been missing. The lack of an overview is made clear by confusions about algorithm and group names in the existing literature. This article is a review aimed at explaining and categorizing the various algorithms into groups, according to algorithm implementation. The algorithms are compared based on published data and our own laboratory results. Positive and practical uses of the various algorithms for different applications are discussed, with a focus on image guidance.

... 7 Conclusions In this paper, we have proposed a geometry-based image representation scheme and an algo-rithm/function for retrieving i&amp;D images of relevance (based on spatial similarity) to ... The algorithm is robust-in the sense that it can recognize translation and scale ...

Suppose that a random process Z(s; t), indexed in space and time, has a spatio-temporal stationary covariance C(h; u), where h 2 IR d (d 1) is a spatial lag and u 2 IR is a temporal lag. Separable spatio-temporal covariances have the property that they can be written as a product of a purely spatial covariance and a purely temporal covariance. Their ease of de nition is counterbalanced by the rather limited class of random processes to which they correspond. In this article, we derive a new approach that allows one to obtain many classes of nonseparable, spatio-temporal stationary covariance functions and we t several such to spatio-temporal data on wind speed over a region in the tropical western Paci c ocean.

In this paper, we investigate a new approach to the cooccurrence matrix currently used to extract textural features: co-occurrence matrices for volumetric data. While traditional texture metrics have concentrated on 2D texture, 3D imaging modalities are becoming more and more prevalent, providing the possibility of examining texture as a volumetric phenomenon. Just as computer graphics have used 3D textures as a more realistic alternative to 2D texture mapping, we expect that texture derived from volumetric data will have better discriminating power than 2D texture derived from slice data. An experimental study has been conducted in which the results for textural features derived from 2D are compared to those results derived from using cooccurrence matrices for volumetric data. Our preliminary experimental results indicate that the volumetric texture features have better discriminating power than 2D texture derived from slice data.

Region growing is a very useful technique for image segmentation. Its efficiency mainly depends on its aggregation criterion. In the present paper, a new algorithm is proposed with a homogeneity criterion based on an adequate tuning between spatial neighbourhood and histogram neighbourhood. It differs from other techniques by reconsidering the pixel (or voxel) assignments on each step by a process which minimizes variance through special dilations. Thus, the region created by an initial seed can be non-connected and possibly does not contain this seed. Examples are given in dental surgery for 2D X-Ray images (and their associated 3D block) and for 3D images acquired by the Morphometre, the new 3D scanner constructed by GEMSE (General Electric Medical Systems). © 1997 Published by Elsevier Science B.V.

Cleft lip and palate (CLP) affects the dentoalveolar and nasolabial facial regions. Internal and external nasal dysmorphology may persist in individuals born with CLP despite surgical interventions. 7-18 year old individuals born with unilateral and bilateral CLP (n 5 50) were retrospectively assessed using cone beam computed tomography. Anterior, middle, and posterior nasal airway volumes were measured on each facial side. Septal deviation was measured at the anterior and posterior nasal spine, and the midpoint between these two locations. Data were evaluated using principal components analysis (PCA), multivariate analysis of variance (MAN-OVA), and post-hoc ANOVA tests. PCA results show partial separation in high dimensional space along PC1 (48.5% variance) based on age groups and partial separation along PC2 (29.8% variance) based on CLP type and septal deviation patterns. MANOVA results indicate that age (P 5 0.007) and CLP type (P 0.001) significantly affect nasal airway volume and septal deviation. ANOVA results indicate that anterior nasal volume is significantly affected by age (P 0.001), whereas septal deviation patterns are significantly affected by CLP type (P 0.001). Age and CLP type affect nasal airway volume and septal deviation patterns. Nasal airway volumes tend to be reduced on the clefted sides of the face relative to non-clefted sides of the face. Nasal airway volumes tend to strongly increase with age, whereas septal deviation values tend to increase only slightly with age. These results suggest that functional nasal breathing may be impaired in individuals born with the unilateral and bilateral CLP deformity. Clin. Anat. 00:000-000,

The emerging cloud gaming service has been growing rapidly, but not yet able to reach mobile customers due to many limitations, such as bandwidth and latency. We introduce a 3D image warping assisted real-time video coding method that can potentially meet all the requirements of mobile cloud gaming. The proposed video encoder selects a set of key frames in the video sequence, uses the 3D image warping algorithm to interpolate other non-key frames, and encodes the key frames and the residues frames with an H. ...

Face recognition is one of the most challenging biometric modalities for personal identification. This is due to a number of factors, including the complexity and variability of the signal captured by a face device. Several issues incur in the management of a face template as user's identity. Data dimensionality reduction, compactness of the representation, uniqueness of the template and ageing effects, are just but a few of the issues to be addressed. In this paper we present the current state of the art in face recognition technology and how this related to the proper management of a user's identity. Some real cases are presented and some conclusions are drawn.

3D imaging sensors for the acquisition of three dimensional (3D) shapes have created, in recent years, a considerable degree of interest for a number of applications. The miniaturization and integration of the optical and electronic components used to build them have played a crucial role in the achievement of compactness, robustness and flexibility of the sensors. Today, several 3D sensors are available on the market, even in combination with other sensors in a "sensor fusion" approach. An importance equal to that of physical miniaturization has the portability of the measurements, via suitable interfaces, into software environments designed for their elaboration, e.g., CAD-CAM systems, virtual renders, and rapid prototyping tools. In this paper, following an overview of the state-of-art of 3D imaging sensors, a number of significant examples of their use are presented, with particular reference to industry, heritage, medicine, and criminal investigation applications.

Deformable models, such as the discrete active contour and surface, imply the use of iterative evolution methods to perform 2D and 3D image segmentation. Among the several existing evolution methods, we focus on the greedy algorithm, which minimizes an energy functional, and the physics-based method, which applies forces in order to solve a dynamic differential equation. In this paper, we compare the greedy and physics-based approaches applied on 2D and 3D models, as regards overall speed and segmentation quality, quantified with an evaluating function mainly based on the mean distance between the model and the desired shape.

Validation studies of the new DentalPrintr software were carried out with experimental bite marks in pigskin. The bite marks were
digitally photographed according to the ABFO guidelines for evidence collection. Dental casts used in the experiment were scanned in 3D and 2D,
and comparison overlays were generated using DentalPrintr and Adobes Photoshops software, respectively. Digitized photographs of the
experimental bite marks and the biting edges obtained in the overlays were compared by two different examiners to analyze the impact of training
and experience with the two methods. Receiver operating characteristic (ROC) analysis, sensitivity, specificity, and 95% confidence intervals for
each cutoff point were calculated. The expert examiner using DentalPrintr obtained the best results, with an area under the ROC curve of 0.76
(SE 5 0.057; CI at 95% 5 0.652–0.876). Fairly high specificity values were found for DentalPrintr, and the best results were obtained for the
cutoff value that discriminated between the examiner’s response ‘‘biter’’ and the rest of the possible (specificity 97.9%, CI at 95% 5 93.2%–
99.6%). Therefore, the results presented here indicate that DentalPrintr is a useful, accurate tool for forensic purposes, although further research
on the comparison process is needed to enhance the validity of bite mark analysis.

Introduction The current authors have developed a modular system of reference array Wxation which is tailored spe-ciWcally to the spinal level being operated upon. They believe that this system may further increase the precision and accuracy of pedicle screw placement. Materials and methods Two formalin-Wxed whole body cadavers were used for this study. For cervical spine evaluation of the reference clamp, four odontoid screws (two per cadaver) for C1/C2-fusion and four lateral mass screws (two per cadaver) were implanted. Following navigated screw placement with 2D and 3D Xuoroscopic veriWcation, insertion of two lateral mass screws was performed. In the same way, lumbar and thoracic pedicle screws were implanted. Two pedicle screws were placed at two levels of the lumbar and two levels of the thoracic areas giving an overall of 16 screws implanted (8 cervical, 4 thoracic, and 4 lumbar). Postoperative evaluation involved comparison of postoperative 3D scans and preoperative planning images. A simple classiWcation system was used for evaluation of any deviation from the planned trajectory. Results All pedicle screw placements were performed as planned without any technical problems. The reference array clamps remained in position at all the spinal levels at which they were employed with no loosening or displacement and no secondary damage to any of the spinous processes. Manual manipulation was performed but no displacement or slippage was observed. Image artefacts caused by the reference clamp were not signiWcant as to obscure the area of interest. Both imaging modalities (Iso-C 3D and Vario 3D) generated suYciently precise 3D images. There was no substantial diVerence in quality when those two systems were compared. Discussion InsuYcient Wxation of the reference clamp can lead to failure and complications. To date, no reference clamp systems have been developed speciWcally for navigated spine surgery. Conclusions Stable reference array Wxation is a critical step in navigated surgery. To date, the same reference clamps have been applied to the spinal anatomy as have been developed originally for the appendicular skeleton. The current investigators have developed a novel modular clamp and have demonstrated its eYcacy in a cadaveric model.

A multidimensional image navigation and display software was designed for display and interpretation of large sets of multidimensional and multimodality images such as combined PET-CT studies. The software is developed in Objective-C on a Macintosh platform under the MacOS X operating system using the GNUstep development environment. It also benefits from the extremely fast and optimized 3D graphic capabilities of the OpenGL graphic standard widely used for computer games optimized for taking advantage of any hardware graphic accelerator boards available. In the design of the software special attention was given to adapt the user interface to the specific and complex tasks of navigating through large sets of image data. An interactive jog-wheel device widely used in the video and movie industry was implemented to allow users to navigate in the different dimensions of an image set much faster than with a traditional mouse or on-screen cursors and sliders. The program can easily be adapted for very specific tasks that require a limited number of functions, by adding and removing tools from the program's toolbar and avoiding an overwhelming number of unnecessary tools and functions. The processing and image rendering tools of the software are based on the open-source libraries ITK and VTK. This ensures that all new developments in image processing that could emerge from other academic institutions using these libraries can be directly ported to the OsiriX program. OsiriX is provided free of charge under the GNU open-source licensing agreement at http://homepage.mac.com/rossetantoine/ osirix. KEY WORDS: DICOM viewer, 3D, image fusion, dynamic series, open-source software T HE RAPID EVOLUTION of digital

The 3D image correlation technique is used for full field measurement of strain (and strain rate) in compression and tensile split Hopkinson bar experiments using commercial image correlation software and two digital high-speed cameras that provide a synchronized stereo view of the specimen. Using an array of 128×80 (compression tests) and 258×48 (tensile tests) pixels, the cameras record about 110,000 frames per second. A random dot pattern is applied to the surface of the specimens. The image correlation algorithm uses the dot pattern to define a field of overlapping virtual gage boxes, and the 3-D coordinates of the center of each gage box are determined at each frame. The coordinates are then used for calculating the strains throughout the surface of the specimen. The strains determined with the image correlation method are compared with those determined from analyzing the elastic waves in the bars, and with strains measured with strain gages placed on the specimens. The system is used to study the response of OFE C10100 copper. In compression tests, the image correlation shows a nearly uniform deformation which agrees with the average strain that is determined from the waves in the bars and the strains measured with strain gages that are placed directly on the specimen. In tensile tests, the specimen geometry and properties affect the outcome from the experiment. The full field strain measurement provides means for examining the validity and accuracy of the tests. In tests where the deforming section of the specimen is well defined and the deformation is uniform, the strains measured with the image correlation technique agree with the average strain that is determined from the split Hopkinson bar wave records. If significant deformation is taking place outside the gage section, and when necking develops, the strains determined from the waves are not valid, but the image correlation method provides the accurate full field strain history.

Here we describe a MATLAB toolbox for analysis of 3D images obtained using a 3D scanner. Toolbox consists of two main parts: various filters for improving the image quality and a module for surface reconstruction from an unorganized set of points.

The launch of the Microsoft Kinect for Xbox (a real-time 3D imaging device) and supporting libraries spurred the development of various applications including those with natural user interfaces. We propose that using Kinect offers opportunities for novel approaches to classroom instruction on natural user interaction. A number of development frameworks has come up that can be used to facilitate this instruction. We evaluate the current state of this technology and present an overview of some of its development frameworks. We then present examples of how Kinect-assisted instruction can be used to achieve some of the learning outcomes in Human Computer Interaction (HCI) courses as outlined in IT2008. We have verified that OpenNI, with its accompanying libraries, can be used for these activities in multiplatform learning environments.

Background 3D cone beam imaging allows localization of impacted canines, using spatial relationships, with excellent tissue contrast. The aim of this project was to assess the degree of difficulty for the treatment of impacted canines, based on the 3D information provided by cone beam imaging.

Purpose: To report the results of an analysis of dose received to tissues and organs outside the target volume, in the setting of spinal axis irradiation for the treatment of medulloblastoma, using three treatment techniques. Methods and Materials: Treatment plans (total dose, 23.4 Gy) for a standard two-dimensional (2D) technique, a three-dimensional (3D) technique using a 3D imaging-based target volume, and an intensity-modulated radiotherapy (IMRT) technique, were compared for 3 patients in terms of dose-volume statistics for target coverage, as well as organ at risk (OAR) and overall tissue sparing. Results: Planning target volume coverage and dose homogeneity was superior for the IMRT plans for V 95% (IMRT, 100%; 3D, 96%; 2D, 98%) and V 107% (IMRT, 3%; 3D, 38%; 2D, 37%). In terms of OAR sparing, the IMRT plan was better for all organs and whole-body contour when comparing V 10Gy , V 15Gy , and V 20Gy . The 3D plan was superior for V 5Gy and below. For the heart and liver in particular, the IMRT plans provided considerable sparing in terms of V 10Gy and above. In terms of the integral dose, the IMRT plans were superior for liver (IMRT, 21.9 J; 3D, 28.6 J; 2D, 38.6 J) and heart (IMRT, 9 J; 3D, 14.1J; 2D, 19.4 J), the 3D plan for the body contour (IMRT, 349 J; 3D, 337 J; 2D, 555 J). Conclusions: Intensity-modulated radiotherapy is a valid treatment option for spinal axis irradiation. We have shown that IMRT results in sparing of organs at risk without a significant increase in integral dose. Ó 2007 Elsevier Inc.

As technologies for acquiring 3D data and algorithms for constructing integrated models evolve, very large data sets representing objects or environments are emerging in various application areas. As a result, significant research in computer graphics has aimed to interactively render such models on affordable commodity computers. Interest is growing in the possibility of integrating real-time analysis and transformation tools in interactive visualization environments as they become more available.

Three-dimensional (3D) ultrasound (US) is increasingly being introduced in the clinic, both for diagnostics and image guidance. Although dedicated 3D US probes exist, 3D US can also be acquired with the still frequently used two-dimensional (2D) US probes. Obtaining 3D volumes with 2D US probes is a two-step process.

MaZda, a software package for 2D and 3D image texture analysis is presented. It provides a complete path for quantitative analysis of image textures, including computation of texture features, procedures for feature selection and extraction, algorithms for data classification, various data visualization and image segmentation tools. Initially, MaZda was aimed at analysis of magnetic resonance image textures. However, it revealed its effectiveness in analysis of other types of textured images, including X-ray and camera images. The software was utilized by numerous researchers in diverse applications. It was proven to be an efficient and reliable tool for quantitative image analysis, even in more accurate and objective medical diagnosis. MaZda was also successfully used in food industry to assess food product quality. MaZda can be downloaded for public use from the Institute

Potential applications of volume rendering in musculo-skeletal disorders Three dimensional imaging is increasingly important for evaluation of anatomic relationships and extent of disease, for treatment planning and for follow-up evaluation. The volume rendering technique allows creation of accurate 3D images that can be used for several clinical applications especially in musculo-skeletal disorders such as evaluation of tumors or fractures. This

A panoramic cardiac imaging system consisting of three highspeed CCD cameras has been developed to image the surface electrophysiology of a rabbit heart via fluorescence imaging using a voltage-sensitive fluorescent dye. A robust, unique mechanical system was designed to accommodate the three cameras and to adapt to the requirements of future experiments. A unified computer interface was created for this application-a single workstation controls all three CCD cameras, illumination, stimulation, and a stepping motor that rotates the heart. The geometric reconstruction algorithms were adapted from a previous cardiac imaging system. We demonstrate the system by imaging a polymorphic cardiac tachycardia.

This exciting series publishes both monographs and edited thematic collections in the broad areas of cultural heritage, digital humanities, collecting and collections, public history and allied areas of applied humanities. In the spirit of our mission to take a stand for the humanities, this series illustrates humanities research keeping pace with technological innovation, globalization, and democratization. We value a variety of established, new, and diverse voices and topics in humanities research and this series provides a platform for publishing the results of cuttingedge projects within these fields. LIST OF ILLUSTRATIONS and Space in Cultural Heritage (www.cosch.info), supported by the European Cooperation in Science and Technology (COST, www.cost.eu). COST is a funding agency for research and innovation networks. COST Actions help connect research initiatives across Europe and enable scientists to grow their ideas by sharing them with their peers. This boosts their research, career and innovation.

Object This article describes a method for automated extraction of branching structures in three dimensional (3D) medical images. Materials and methods The algorithm recursively tracks branches and detects bifurcations by analyzing the binary connected components on the surface of a sphere that moves along the vessels. Local segmentation within the sphere is performed using a clustering algorithm based on both geometric and intensity information. It minimizes a combination of the intra-class intensity variances and of the inertia moment of the “vessel” class, which emphasizes the cylindrical structures. The algorithm was applied to 16 MRA and 12 CTA 3D images of different anatomic regions. Its capability of extracting all the branches and avoiding spurious detections was evaluated by comparing the number of extracted branches with the number of branches found by visual inspection of the datasets. Its reproducibility and sensitivity to parameter variation were also assessed. Results With a fixed parameter setting, 68 out of 286 perceptible branches were missed or partly extracted and 11 spurious branches were obtained. Increasing the weight of the geometric criterion helped in tracking the principal branches in noisy data but increased the number of missed branches. Processing time was within 5 min per dataset. Conclusion From one initial point, the algorithm extracts a vascular tree where the differences of size and of intensity between the branches are not large. Missed sub-trees can be recovered using additional starting points.