Table 1.

Atrophic Acne Scar Subtypes

Scar Type	Morphology
Ice Pick	Diameter: <2 mm
	Depth: Lower dermis/subcutis
	Visual: V-shaped, pitted appearance
Boxcar	Diameter: 1–4 mm
	Depth: Upper dermis (shallow) or lower dermis (deep)
	Visual: Round or geometric appearance with vertical walls and flat base
Rolling	Diameter: ≥4 mm
	Depth: Upper dermis
	Visual: Slopy, undulating appearance caused by fibrotic tethering of dermis to subcutaneous layer

Notes: Reproduced with permission from Dove Medical Press. Tam C, Khong J, Tam K, Vasilev R, Wu W, Hazany SA. Comprehensive Review of Non-Energy-Based Treatments for Atrophic Acne Scarring. Clin Cosmet Investig Dermatol. 2022;15:455–469.⁷