How to fill blood vessel pixels

I want to fill the blood vessel pixel with 1's and at the same time I want to remove the noisy little spots from the image. This image is obtained after the application of canny edge detector to source image. I will be grateful for your help.

Answer 1

[Image Analyst]

Maybe Canny is not the way to go. Is that one of the methods listed in section 20.5 here: VisionBib ophthalmology articles, or are there better methods listed? Don't waste time on a method known to be not very good. Find a published one that works, and then improve it if you want. If you're doing this for graduate research, you can't publish a paper on some old elementary algorithm. You either have to invent a new one or improve on an existing one.