Most patients do not notice it until they see straight lines becoming wavy or out of shape. Your vision may be still good but objects will appear distorted when compared to the other eye. At the eye doctor, the diagnosis is confirmed with a dilated eye examination and a special test called Optical Coherence Tomography (OCT). It is caused by overgrowth of scar tissue on the surface of the retina and this may be due to previous retinal diseases like uvetis, retinal detachment, retinal hole, or trauma.