For acne scar treatment, is there typically more improvement in the first or last few treatments, and how much % improvement can I expect after each session?

Subjectively, most of my patients report more perceptible improvement after the 2nd-4th treatment sessions if typically they undergo treatments spaced 1-2 months apart.

This corresponds to the new collagen formation stimulated by the treatment which starts about 1-2 months after each treatment and tapers off 4-6 months after treatment assuming no further treatment is performed.

8-15% improvement is to be expected after each treatment.

After about 4-6 treatments, results generally start to taper off although a small group of my patients continue to observe improvement beyond the 6th treatment.