Issue with my Macbook Desktop? With picture

So my macbook pro (late 2010) has these 2 lines on the desktop? At first i thought it might be something in my display but when i open other apps, the lines cant be seen? its only specifically on my desktop. i have attached an image for you to see what I'm talking about? Any ideas? you will see the blue lines in the center on the black background and off to the left...

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I wonder if it's in the desktop background Image itself? Have you tried different backgrounds?

try different backgrounds, and also try moving an internet browser with something black on it over the area to see if its an issue with displaying black