Self-harm scar removal options after Discovery Pico Laser (6) & 1 PRP treatment? (Photo)

I have self harm scars on my arm that are about 4 years old. I had 6 treatments with the Discovery Pico laser and one PRP treatment but I'm completely dissatisfied with the results, as the scars are almost as visible as they were before and I still can't wear short-sleeved shirts or go to the beach. What other procedures could I try to remove the scars entirely or minimize their appearance so they are barely visible?