**15. Hypertrophic scar or keloid**

Keloid and hypertrophic scarring are rare occurrences in hair transplant complications. The reported incidence of keloid and hypertrophic scarring in hair transplantations is 0.1%. They represent an abnormal response to dermal injury, characterized by exuberant collagen deposition. Keloid scaring usually develops months or years after surgery and persists indefinitely. Individuals with a history of keloid scarring are not candidates for hair restoration surgery. Those with a high risk of developing keloids, due to ethnicity and age, or with a personal history of hypertrophic scarring, should be informed of the potential for abnormal scarring [9, 10].
