Magnetic resonance image enhancement, Biology

Over the last three decades medical imaging has developed to be an important tool for medical condition diagnosis, treatment planning and surgery. The insight provided by information contained in medical images has become essential in providing the community with 'a better life' and 'a healthy lifestyle'. Medical imaging aims to promote life and prolong life expectancy within the wider community by increasing our knowledge of healthy and diseased processes. Medical imaging tools to better delineate and identify information are necessary to impart clarity to the medical profession. High field Magnetic Resonance Imaging (MRI) has had much development in the last five years and Susceptibility Weighted Imaging (SWI) has emerged as an image post-processing technique. Mostly the magnitude of the complex data is illustrated as intensities in images, but in SWI, the additional information contained in the phases is used to enhance what is captured in magnitude images. The extracted additional level of detail can be used in traumatic brain injury, stroke and other brain disorders, to better delineate the spatial severity of the problem. Assignment 1 is related to how SWI can be used to enhance magnetic resonance images. In MRI the presence of a magnetic field induces the relaxation of protons. This relaxation in time is captured as a signal through the generation of an echo. The signal is time series data

and is referred to as the Free Induction Decay (FID). In this assignment it is assumed that proton (1H - hydrogen) relaxation data has been acquired and is stored as signal magnitude and phase. The provided data are in image space, and generated after data derived from the FID was 2D Fourier transformed. The actual raw data collected by the scanner can be computed by taking the inverse 2D Fourier transform of the complex image intensities. As part of this assignment you are provided with '2dseq' files containing magnitude and phase information and 'acqp' file consisting of data acquisition parameters. These files were generated on a Bruker 16.4T research scanner using Paravision 4.0. The echo signals were generated using a T2 * weighted gradient echo (i.e. transverse relaxation) image acquisition sequence. The assignment requires that the data is read, processed and susceptibility weighted images are reconstructed. You are required to submit your m-files and answers on blackboard. Each question must be a function in a separate m-file executed and saved as A1QX.m (X=1, 2, 3 or 4). You should save your answers and plots, combine these into a PDF file and submit it along with your m- files. Clearly mark which question you are answering and label all plots. You are not required to write lengthy answers, simply provide what is asked. You will not only receive marks for correct answers, but also for clarity of your presentation. This means that your algorithms should use indenting, explanatory comments for variables and complicated lines of code. You should use your research and searching skills to investigate any terms that you do not understand.

QUESTION 1

Using the supplied read_2dseq.m file read the provided files into MATLAB (useful Matlab commands: abs, image, axis, caxis, imagesc, colormap, figure, subplot, title). The results should be illustrated as figure 1, using four subplots and gray scale. The following questions should be illustrated as separate plots in figure 1. For slice number 100, illustrate the following:

(a) Normalised magnitude image

(b) Scaled phase imaged in [-Π, Π]

(c) Real part of the image

(d) Imaginary part of the image

QUESTION 2

You need to filter slice 100 phase images to identify microscopic phase changes contained amongst macroscopic phase variations (Note: file QualityGuidedUnwrap2D.m has been supplied to you).

(a) Low-pass filters the images using an 8*8 boxcar filter. (Note: Boxcar method smooths the variations through averaging, effectively reducing the amount of high frequency variations. Furthermore, it helps if the phases are first unwrapped).

(b) Illustrate the microscopic phase variations. (Note: Difference between original phase and new phase is high-pass filtered phase).

Posted Date: 3/2/2013 12:37:43 AM | Location : United States







Related Discussions:- Magnetic resonance image enhancement, Assignment Help, Ask Question on Magnetic resonance image enhancement, Get Answer, Expert's Help, Magnetic resonance image enhancement Discussions

Write discussion on Magnetic resonance image enhancement
Your posts are moderated
Related Questions
You are interested in plant life history evolution, you come across a population of the California poppy that i spolymorphic (mixed) for both iteroparous ans semeparous individuals

phylum and chordata ex. and their classiication

Post-parturient haemoglobinuria (pph) in cattle and buffaloes The post-parturient haemoglobinuria (PPH) is an acute disease of high yielding buffaloes and cows. The disease oc

Q. Why are vaccines made of the own disease agent or of fragments of it? The goal of vaccines is to artificially induce a specific primary immune response (and the consequent f

Regarding solubility, how are lipids classified? Fats and oils are hydrophobic molecules, i.e., they are non polar and insoluble in water. Lipids in general are molecules with

Agroup of realated genera are classified as-?

What are plant organs responsible for the perception of light variation? And what is the pigment responsible for this perception? The Leaves are mostly responsible for percepti

Q. How does the body defend itself from microorganisms and other harmful substances that enter the airway during the breathing process? The epithelium of the airway is a ciliat

Explain Effect of Nutrient Supplements on Drugs? A nutrient or nutrient supplement can alter the pharmacological action of a drug by enhancing the drug effect or by opposing it

Q. Cardiac Catheterization of mitral stenosis? Cardiac catheterization is rarely needed to diagnose mitral stenosis. An end diastolic gradient more than 5 mm Hg. across mitral