Enhancements To Editions
There are such things as enhanced or embellished or
highlighted works and for some crazy art reason there are
many terms for this one thing. It all boils down to a point
where either the artist or someone nominated by the artist
has gone over the painting with oil paint or acrylic paint
depending on what the artist chooses to use.  The
highlighting or enhancement or embellishment or retouch
takes place on the reproduction and hopefully adds depth
and dimension reminiscent of the original.
The exact details are very simple, the artist will go in
with a paint brush after the print dries and will enhance
certain portions of the painting to add light dimension or
color, sometimes just signing in oil can be considered an
embellishment.
This has become quite popular; in fact some artists
charge a heavy premium for these enhanced pieces, while
not doing terribly much enhancement.
When the artist is finished retouching the piece is
sprayed with a special UV light inhibiting lacquer to seal it
for ages.  The new ultraviolet inhibiting coats claim to
double the life span of whatever media they are applied to.
But they are highly toxic when being sprayed, so much so
that the person spraying the coat must wear a protective
mask. The only other issue, I've noticed, with these UV
coatings is under the right circumstances they can peal or
bubble. This usually only happens to low quality coatings.
Also watch out for scotch tape applied to the print as a way
of keeping it flat in a drawer, because once you've removed
the scotch tape, a portion of the coating may have come off
with it.