Lash Enhancements are one of my very favorite permanent makeup applications to do for women - simply because it is so subtle, yet makes such a big difference in the appearance of your eyes.
The lash enhancement is simply tattooed into the lash line to subtlety enhance. It is not as thick as an eyeliner, so you don't get the obvious "line".
I personally feel that this is a style of permanent makeup that I feel is appropriate for any age. A lash enhancement is more likely to need touch-ups sooner than an eyeliner, but has approximately 5-7 years of wear depending on your lifestyle.