The oculus rift kits come with three sets of lenses-A, B and
C. lens pair A is to be used by people who have excellent
long sighted eyesight as the rift is focused at infinity. The
pairs B and C are to be used by people having problems with
near sightedness, though cannot be used by all, especially
people with major vision complications.
Also precise care should be taken while changing the lenses.
A tiny dust particle if gets settled on the lens creates a dead
pixel view in the VR. To worsen it further one can expect
dust particles in both the lenses at different locations.
Furthermore glasses can also be worn along with the oculus
rift goggles, provided that the glasses are not huge.