With Google, or any other good search engine, this should take only a minute. Omitting this important step can cause the following problems later on:
1. When people search for your paper, they will end up finding a different paper.
2. The reviewers might think that you are using the title to steal someone else's reputation; this is bad for you.
Just in case; if you ever thought of using a title similar to that of a good paper, just to attract readers, don't do it! That is totally unethical!! And more, people will soon find out.
Recently, I searched for the paper:
Marziliano, P., Dufaux, F., Winkler, S. & Ebrahimi, T. (2002), "A no-reference perceptual blur metric", In Proc. International Conference on Image Processing, Vol. 3, pp.57-60, 2002.
Luhong Liang; Jianhua Chen; Ma, Siwei; Debin Zhao; Wen Gao, "A no-reference perceptual blur metric using histogram of gradient profile sharpness," Image Processing (ICIP), 2009 16th IEEE International Conference on , vol., no., pp.4369,4372, 7-10 Nov. 2009
One can argue that the authors of the second paper were unaware of the first. But the list of references in the second paper includes:
P. Marziliano, F. Dufaux, S. Winkler, et al, "Perceptual blur and ringing metrics: application to JPEG2000", Signal Proc.: Image Commu., 19(2), pp. 163–172, 2004.
This is a later work by P. Marziliano, and less related to the topic compared to the original paper. So, no one can blame anybody who suspects that the title was "copied".
If you do something like this by mistake, it will embarrass not only you, but also your co-authors. Especially your advisor who won't spend much time checking this kind of detail :-p