PVR = proliferative vitreo-retinopathy. Usually caused by retina not getting enough blood and abnormal blood vessels develop that cause scarring and bleeing into the eye. Most common cause is diabetes. ERM is membrane developing on the surface of the retina, generally not a problem unless its over the macula. they are different problems PVR can lead to blindness but ERM can't.
Thank you for the explanation. I apologize for the poorly worded question. Let me try again. How do the membranes associated with PVR differ from epiretinal membranes? Thank you again for your time and effort.
PVR usually bigger, more aggressive, grow above the surface of the retina, may bleed, may cause traction retinal detachment.