The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
MRI studies in post-traumatic stress disorder (PTSD) have focused primarily on manual based hippocampal volumetry, which is located in the subcortical. However, the cortical reduction or increase caused especially by thickness changes has not been well investigated. Recent advances in computational analysis provide new opportunities to use fully automatic techniques to measure cortical thickness,...
Root is an important plant organ for nutrient and water uptake from the surrounding medium such as soil. Due to its special growing environment and structural complexity, it is more difficult to quantify plant root than its shoot. Observation and measurement of plant root in situ have been the technical bottleneck to understand root systems. Available methods used to observe root system were reviewed...
Effective processing of source data matched to appropriate visualisation can greatly enhance the user's ability to explore and comprehend complex information. While this is a fundamental problem for many domains, in medical applications it is particularly important. None-invasive scanning technologies, such as MRI, have greatly enhanced our ability to `image' the internal body, however the resultant...
In order to evaluate the specific brain activities related to the recognition of a three-dimensional (3D) structure, the construction of 3D images in the brain from 2D figures and the ability to match the mental image to an actual 3D object were investigated. The results demonstrated that the effects of depth cues (shade and colors) in the 3D images facilitated the cognitive process in human-computer...
Position Emission Tomography (PET) allows the in-vivo monitoring of functional processes in the body. However its limited spatial resolution induces Partial Volume Effect (PVE), which leads to a loss of signal in tissues of size similar to the Point Spread Function (PSF) of the imaging device and induces activity spillover between adjacent structures with different amounts of activity. The aim of...
In this work, a nonconvex Compressive Sensing model targeted at true 3D reconstructions of highly undersampled MR angiograms acquired with parallel imaging is proposed. When combined with the Max-CAPR acquisition sequence, it is demonstrated that high quality, non-view-shared, 3D images of the contrast-filled neurovasculature can be acquired (at acceleration factors exceeding the number of coils)...
It is implicitly assumed in most non-rigid registration methods that either corresponding structures can be found in both images, or that the regularization associated with the class of transformations chosen produce pertinent deformations elsewhere. However, when the images to register have a different contrast and resolution (e.g. in vivo / post mortem), or to minimize the deformation of some specific...
This paper presents an automated method for measuring 3D left ventricular (LV) strain in each imaged time frame from phase unwrapped harmonic phase (HARP) images derived from tagged cardiac magnetic resonance imaging. In previous work, manually-placed branch cuts were used to resolve phase inconsistencies in HARP images before they were unwrapped. This paper presents an automated method for placing...
We address the difficult problem of segmenting the inflamed synovial tissue in multi-modal 3D MR sequences of the wrist. The complex morphology of the structures to segment, the dimensionality of the images, and the multiple modalities all contributes to the difficulty of the problem. We propose a solution based on a voxel classifier built on relatively few features selected from a large pool computed...
Advances in medical imaging techniques and devices has resulted in increased use of imaging in monitoring disease progression in patients. However, extracting decision-enabling information from the resulting longitudinal multi-modal image sets poses a challenge. Radiologists often have to manually identify and quantify certain regions of interest in the longitudinal image sets, which bear upon the...
Understanding the mechanisms of eye movement is difficult without a realistic biomechanical model. We present an efficient and robust computational framework for building subject-specific models of the orbit from magnetic resonance images (MRIs). We reconstruct three-dimensional geometric models of the major structures of the orbit (six extraocular muscles, orbital wall, optic nerve, and globe) by...
Many analyses in neurosciences are carried out on histological and autoradiographic datasets and performed by manually drawing regions of interest on these 2D postmortem data. Such task being time-consuming, we propose an automated segmentation strategy to analyze 3D postmortem brain images. This method is based on the co-registration of a MRI-based 3D digital atlas on 3D-reconstructed postmortem...
Solar imaging is currently an active area of research. In this study a 3D modeling technique for magnetic field lines on Sun is provided. Magnetic field foot prints are detected from SOHO (Solar and Heliospheric Observatory) / MDI (Michelson Doppler Imager) Magnetogram images. Using negative and positive footprints possible dipole pairs are found according to their proximity. Then using this data,...
Medical image segmentation and 3D mesh generation are the two critical challenges for numerical analysis based on medical images. Seamlessly linking different segmented results to appropriate mesh generation algorithms should be greatly beneficial for automatic and rapid finite element modeling from medical images. We present the interface representation models between segmentation and mesh generation...
Image-guided therapy procedures require the patient to remain still throughout the image acquisition, data analysis and therapy. This imposes a tight time constraint on the over-all process. Automatic extraction of the pathological regions prior to the therapy can be faster than the customary manual segmentation performed by the physician. However, the image data alone is usually not sufficient for...
Traditional fMRI analysis has focused on modeling temporal changes in BOLD signals on a voxel-by-voxel basis to infer brain activation. To incorporate spatial information, we have previously proposed to model the spatial changes in the distribution of BOLD signals within regions of interest. Specifically, we examined changes in the spread of BOLD signals and the distribution of signals along the three...
In this work, we apply the UNFOLD technique to a hybrid 3D-EPI sequence in order to accelerate image acquisition for fMRI studies. UNFOLD is used in the 3D slice encoding direction which directly doubles the temporal resolution. Combining UNFOLD with Partial Fourier acqusition further reduces the acquisition time for a whole brain volume from 2.4 seconds to 1 seconds. The sequence was tested on healthy...
Recently, many groups have reported on the occurrence of brain shift in stereotactic surgery and its impact on the procedure. A shift of deep brain structures by only a few millimeters can potentially increase the number of required microelectrode and/or macroelectrode tracks. This can cause complications and potentially affect implantation accuracy. Detecting intra-operative brain shift and, more...
Q-ball imaging (QBI) is a high angular resolution diffusion imaging (HARDI) technique which has been proven very successful in resolving multiple intravoxel fiber orientations in MR images. The standard computation of the orientation distribution function (ODF, the probability of diffusion in a given direction) from q-ball uses linear radial projection, neglecting the change in the volume element...
We aim to fill the processing gap in 300 mm wafer-scale non-Bosch TSV etch process by developing production-worthy TSV etch solutions for logic-centric 3D integration. This is based on a magnetically-enhanced capacitively-coupled plasma (CCP) etching system. Key factors in this system that contribute to the control of via features such as global sidewall tapering, local sidewall roughness, Si etch...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.