MATLAB: Noise removal from background

background noiseimage processingImage Processing Toolbox

I have this image
which I obtained after enhancing in order to make the artery clearly visible. I need to know how would I be able to remove the background noise without disturbing the details within the artery itself. I just want to obtain a black background or a background with reduced noise compared to the current noise present. P.S. Artery is represented by the two thick lines going to the right.

Best Answer

Looks like you'd have to "hand paint" it, because I can't really tell what's noise and what are valid blood vessels.