Can micro needling and Latisse help repigment this very old scar ? (Photo)

Thanks for sharing your concern, I know how much long-standing scars can affect confidence. Since your scar is 20 years old and hypopigmented (lacking pigment), it’s more challenging to restore color compared to newer scars. Over time, the pigment-producing cells in that area can become permanently reduced or absent.

Microneedling may help stimulate some remodeling of the skin and, in certain cases, can encourage pigment to return if there are still active melanocytes around the scar. Latisse (bimatoprost) has been used off-label in some cases to help with pigmentation, but results are unpredictable and not guaranteed.

Realistically, full repigmentation of an old scar is rare. Improvement is possible, but the changes tend to be subtle. Sometimes, treatments like fractional lasers, excimer laser, or even medical tattooing (micropigmentation) are considered for more noticeable results.

So while microneedling and Latisse might offer a chance at slight improvement, it’s important to set expectations: the scar may never completely match your surrounding skin in color.

I have personally been performing, with gratifying results, mechanical microneedling (no need for the added expense and risks of RF microneedling) accompanied by the application of Rx topicals, such as bimatoprost, latanoprost and topical tyrosine for many years already for the treatment of hypopigmented scars from all causes, including trauma, acne, self-harm, surgery, etc.
For "mature scars," (I.e. those older than three months , such as the one you describe here, realistic expectations for improvement ranges from 60-80% overall improvement in appearance when the scar is treated with the appropriate needle lengths, technique and aggressiveness needed to achieve optimal results. For this reason I would strongly advise against home self-treatment if this is being contemplated..
You would be wise to consult with an experienced, board certified cosmetic dermatologist scar treatment specialist and best of luck.