Segmentation of the Left Atrium and Pulmonary Veins from Contrast-Enhanced MR Images
Author(s)
Karim, Rashed
Type
Thesis
Abstract
Atrial brillation is an important cardiovascular disease causing cardiac malfunction. The
left atrium and pulmonary veins are the structures most a ected. Radio-frequency catheter
ablation has now become a standard procedure for correcting atrial brillation. The procedure
is minimally invasive and pre-planning the procedure is essential. It is normally required to
image the atrium. Segmentation of the left atrium and pulmonary veins from medical images
is an important problem and a necessary step for further analysing the left atrium.
This dissertation describes techniques for segmenting the left atrium from MR angiography
images. It also describes methods for extracting sub-atrial structures of the atrium such as the
central atrial body and pulmonary veins. As pulmonary veins of the left atrium have complex
vessel networks, the centrelines of these vessels are extracted allowing for better visualisation
and compact representation. Furthermore, the dissertation describes a framework for analysing
the atrium. The pulmonary drainage trees are reconstructed using graph structures. Important
atrial characteristics relevant to catheter ablation procedures are quanti ed. These include
atrial anatomy and ostial diameters.
The methods described in the dissertation are evaluated on real patient datasets and compared
against manual approaches. A comparative study of the proposed left atrium segmentation
algorithm with an existing approach showed that the proposed approach yields better segmentations.
Furthermore, results show that the proposed techniques for pulmonary drainage
reconstruction correctly compute and classify atrial anatomy in the majority of cases. The
computation of ostial diameters also show close agreement with gold-standard measurements.
A series of studies performed to investigate the e ect of user parameters on the quality of
i
segmentation and measurements obtained show reproducibility of results. It is envisaged that
the methods proposed will improve the e cacy of catheter ablation by providing useful and
accurate atrial characteristics and information.
left atrium and pulmonary veins are the structures most a ected. Radio-frequency catheter
ablation has now become a standard procedure for correcting atrial brillation. The procedure
is minimally invasive and pre-planning the procedure is essential. It is normally required to
image the atrium. Segmentation of the left atrium and pulmonary veins from medical images
is an important problem and a necessary step for further analysing the left atrium.
This dissertation describes techniques for segmenting the left atrium from MR angiography
images. It also describes methods for extracting sub-atrial structures of the atrium such as the
central atrial body and pulmonary veins. As pulmonary veins of the left atrium have complex
vessel networks, the centrelines of these vessels are extracted allowing for better visualisation
and compact representation. Furthermore, the dissertation describes a framework for analysing
the atrium. The pulmonary drainage trees are reconstructed using graph structures. Important
atrial characteristics relevant to catheter ablation procedures are quanti ed. These include
atrial anatomy and ostial diameters.
The methods described in the dissertation are evaluated on real patient datasets and compared
against manual approaches. A comparative study of the proposed left atrium segmentation
algorithm with an existing approach showed that the proposed approach yields better segmentations.
Furthermore, results show that the proposed techniques for pulmonary drainage
reconstruction correctly compute and classify atrial anatomy in the majority of cases. The
computation of ostial diameters also show close agreement with gold-standard measurements.
A series of studies performed to investigate the e ect of user parameters on the quality of
i
segmentation and measurements obtained show reproducibility of results. It is envisaged that
the methods proposed will improve the e cacy of catheter ablation by providing useful and
accurate atrial characteristics and information.
Date Issued
2009-09
Date Awarded
2009-09
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Rueckert, Daniel
Creator
Karim, Rashed
Publisher Department
Department of Computing
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)