I have cobblestoning (bumping) after a hair transplant. Can scar gel improve it? (Photo)

It is very difficult to fix a bad hair transplant, cobble stoning, or scarring.  Scar removing gels will not likely help.  Unfortunately there is no clear solution to the scarring.

That cobble stone appearance and pitting are because of technical faulty of implantation of grafts. Silicon based treatments are not effective on that problem . I advice you to have a dense packing transplantationas a revisionsurgery to camouflage the cobblestoning 

Both can be avoided with proper placement of grafts and at the correct depth. Scar gel will not help as it is not a scar. Hair restoration is not a simple procedure to perfect. Always do research well as you will live with results of hair transplant for the rest of your life.

You have a condition called Cobblestonning which reflects the graft skin edge which is located above the surface of your normal scalp producing these 'bumps'. There is little you can do about this other than get another hair transplant to overwhelm these graft sites. Of course, your surgeon must be aware of the problem where he must place the grafts flat against the surrounding skin at the time of the surgery