5. Conclusion
The segmentation of blood vessels is an active research area which plays a significant role in many medical applications including diagnosis, surgery planning and radiation treatment. The quality of segmentation in the case of the region growing algorithm completely relies on the selection of seed point. In cases where the selected seed point does not belong to the region of interest (vessels), the whole region will be grown incorrectly. MRA, which is used specifically for images of blood vessels, does not contain the required region in start of slices. Applying a region growing algorithm directly from the first slice will result in an inappropriate seed point, thereby leading to poor segmentation. In order to overcome this problem, an ERGA has been proposed. The vessel images generated by ERGA are improved quality as compared to generic RGA.