Agency for Science, Technology and Research

Singapore Agency for Science, Technology and Research Act

Varsha Gupta

Wieslaw Lucjan Nowinski

Ihar Volkau

Bhanu K N Prakash

Ting Ting Ng

Bhanu Prakash K N

Bhanu Prakash Kn

Bhanu KN Prakash

K N Bhanu Parkash

A method is proposed for segmenting a brain image into a CSF region, a WM region and a GM region. An upper limit for the intensity values of a CSF region in the image is estimated such that the points of the image having an intensity less than this upper limit include a subset of the points which form a spatially connected group and which have a peaked intensity distribution. In other words, the invention exploits both the expected spatial distribution and expected intensity distribution of the CSF region. This makes it possible for the method to provide reliable discrimination of the CSF region even in CT images with poor image quality. Various methods are proposed for using the upper limit, and for improving the segmentation accuracy.

Method and system for segmenting a brain image

A method for identifying a pathological region of a scan (such as a stroke region within a MRI DWI volume scan) is proposed. A region of the scan which is likely to contain pathological tissue (e.g. infracted tissue) is identified by obtaining a parameter which, for a given slice, or portion of a slice, characterizes the distribution of the intensity of pixels, e.g. the relative proportion of high intensity pixels. In a first case, such a parameter is used to identify those slices of a volume scan which are likely to include infarction. In a second case, such a parameter (hemisphere parameter) is obtained for each of the left- and right-hemispheres of a brain, to estimate which hemisphere contains the stroke. In either case, the parameter may be calculated based on ranges, percentiles and functions of the percentiles of the intensity distribution. These ranges, percentiles and functions of the percentiles are not pre-defined but are selected to maximize sensitivity.

Method for identifying a pathological region of a scan, such as an ischemic stroke region of an MRI scan

In a method of registering three-dimensional brain images, a reference slice for a midsagittal plane of each image is constructed. The reference slice comprises image points forming a cortical edge. Edge points are selected from these image points such that an ellipse fit to the edge points approximates the cortical edge. The reference ellipse in each image that fits the edge points is determined. The images are registered in a same coordinate system such that the reference ellipses in the images are aligned with one another.

Registering brain images by aligning reference ellipses

Methods (), apparatuses (), and computer program products for segmenting an infarct in a diffusion-weighted imaging (DWI) volume are disclosed. A Region of Interest in at least one slice of the DWI volume is selected (). The ROI comprises at least a portion of the slice. A threshold for a minimum size of an infarct region is selected (). An energy mask is convolved () with that slice, and the resulting energy image is normalized (). The ROI in the convolved energy image is selected (). An initial threshold is determined () using a histogram of the ROI of the slice without a background region, and an initial segmentation of the slice is performed (). Individual components of the initial segmentation of the slice are labeled (). A final threshold is determined () using histograms of labeled components if the initial segmentation, and a final segmentation if the slice is performed () using that threshold.

Segmenting infarct in diffusion-weighted imaging volume

A method of estimating the location of the anterior and posterior commissures in a brain scan image is proposed. Firstly, a geometrical object is constructed using points on a brain scan image of an individual which are on the surface of the brain, such as an ellipse fitting the cerebral surface of a sagittal image of the mid-sagittal plane, or an adjacent sagittal plane. The locations on the MSP of the AC and PC landmarks (and optionally other landmarks) are estimated using the five parameters which define the ellipse, plus numerical values obtained in advance from statistical analysis of other individuals.

Growing community of inventors

Singapore, Singapore

Varsha Gupta