I just found a way to using wilcard with unlink in PHP.
Here is the scenario;
files might be:
120a-some_file1.jpg
210w-some_file1.jpg
some_file123.jpg
480h-some_file1.jpg
somefile.doc

if you want to delete;
120a-some_file1.jpg
200w-some_file1.jpg
480h-some_file1.jpg

you can use this code;

<?php
foreach( glob('*-some_file1.jpg') as $file ){
        unlink($file);
}
?>