Multi-scale Vessel Enhancement Using Local Line Integrals and Variational Optimization

MPhil Thesis Defence


Title: "Multi-scale Vessel Enhancement Using Local Line Integrals and Variational
Optimization"

By

Mr. Yuan Yuan


Abstract

In this thesis, two vessel enhancement techniques are introduced in order
to produce more accurate vesselness measures and vessel direction
estimations that are less subject to local intensity abnormalities.

Vessel enhancement using local line integrals (VE-LLI) is first proposed
which embeds a vessel model by regarding a vessel segment as a straight
line. It uses the second order information of the local line integrals.
Quantities similar to eigenvalues and eigenvectors of the Hessian matrix
are produced, which can be substituted in any existing Hessian-based
enhancement methods.

Given an already enhanced image and its corresponding vessel direction
estimations, a variational optimization (VO) is then introduced as to
further reduce variance of responses inside a vessel segment. A more
generic curve model is embedded and a variational framework is used to
locate the vessel segment that a point belongs to.

Experiments are conduced on 2D retinal images. It is experimentally shown
that VE-LLI produces more accurate vessel direction estimations than
conventional Hessian-based methods. Both VE-LLI and VO can give more
accurate vesselness measures.


Date:				Tuesday, 19 August 2008

Time:				4:00p.m.-6:00p.m.

Venue:				Room 3401
				Lifts 17-18

Committee Members:		Dr. Albert Chung (Supervisor)
				Prof. Dit-Yan Yeung (Chairperson)
				Dr. Huamin Qu


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