9 research outputs found
Estimating retinal vessel diameter change from the vessel cross-section
No full textWe have developed a methodology to estimate small change in the retinal vessel diameter. This technique does not rely on the segmentation of the vessel which is prone to error when the fitted profile does not exactly represent the expected model. Using the newly proposed method, we have identified an inverse linear relationship (p<0.0001, r 2 = 0.965) between the proposed technique with the narrowing of the simulated vessels. The immediate application of this technique is in the caliber change estimation of the time-series retinal vessels, gated with the electrocardiogram
Grey matter volume differences of textual memorization: a voxel based morphometry study
No full textTextual memorization involves intensive memorization techniques and processes, including repetition, rehearsal, and retrieval. Yet, little is known about the possible effects of this robust memorization training on brain structures. Therefore, this study was designed to investigate the presence of structural plasticity in the brain, which may develop after long-term practice of textual memorization techniques. The subjects are a group of huffaz who underwent one year of textual memory training. Twenty-eight volunteers (14 males) were enrolled in this study. Brain images of the subjects were obtained by employing 1.5 Tesla MRI and 3D-MPRAGE imaging sequence. Voxel-based morphometry was applied to assess the gray matter volume differences in the memorizers and the control subjects. The current study found that gray matter volume in the anterior cingulate gyrus, orbitofrontal cortex, left inferior temporal gyrus, right occipitotemporal gyrus, left inferior parietal gyrus, right perirhenal cortex, superior parietal cortex, posterior cingulate cortex and anterior cingulate cortex of the memorizers were significantly increased as compared with the control subjects. The results suggest textual memorization involves with extensive connection across the brain
Fusion of multiscale wavelet-based fractal analysis on retina image for stroke prediction
No full textRetinal stroke prediction using logistic-based fusion of multiscale fractal analysis
No full text10.1109/IST.2010.55484702010 IEEE International Conference on Imaging Systems and Techniques, IST 2010 - Proceedings125-12
Robust methodology for fractal analysis of the retinal vasculature
No full text10.1109/TMI.2010.2076322IEEE Transactions on Medical Imaging302243-250ITMI
Fractal dimension of the retinal vasculature and risk of stroke : a nested case-control study
No full textRecent studies show associations between retinal vascular changes and small infarcts detected on brain imaging, or clinical stroke. Fractal dimension has been used as a global measure of the geometric pattern of the retinal vasculature potentially representing the complex branching pattern of the microvasculature, including the cerebral microvasculature. We have developed an automatic method to assess spectrum fractal dimension (SFD) of the retinal microvasculature using Fourier-transformed images.
Two previous studies have reported cross-sectional associations between retinal fractal dimension and lacunar stroke. In this study, we aimed to examine the association between baseline SFD and stroke incidence using a case-control sample nested in the Blue Mountains Eye Study (BMES)
2D and 3D Complexity Analysis on MRI Images using Fractal Dimension
Get PDFThe brain, which is the most complex structure in the human body, has attracted attention of many researchers to study the possible fractal analysis application upon it. Current interest is seen directed more towards the utilization of complexity analysis as measured by fractal dimension in determining the pathologies effect and degenerative factor on the brain structure volume. In this paper, we used two boxcounting methods: average 2D Fractal Dimension and 3D Fractal Dimension. 47 subjects (19 males, 28 females), aged ranging from 21 to 25 years, were recruited. Brain MRI images were acquired by using 3T MRI system. The images were then thresholded according to Otsu’s method. The processed images were then calculated using fractal analysis, and the values obtained were statistically evaluated using Pearson’s correlation test (r2 = -0.106, p = 0.477). In conclusion, no correlation was seen between average 2D FD and 3D FD
