subcision

Subcision is a minor surgical procedure used to treat atrophic or depressed acne scars. It works by releasing fibrous bands that tether scar tissue to deeper structures, allowing the scar to lift and triggering collagen production in the surrounding dermis. The technique was developed in the 1990s as a minimally invasive option for tethered rolling and some boxcar scars.

Procedure and mechanism: A small needle or blunt cannula is inserted under the scar through the skin. The practitioner moves the instrument to sever the beneath-skin collagen bands, creating tiny separations or channels that release the scar from underlying attachments. Local anesthesia is commonly used. The initial improvement may be visible within weeks as edema resolves and new collagen forms, with additional improvement often seen after subsequent sessions.

Indications and limitations: Subcision is most effective for rolling and tethered atrophic acne scars. It is less predictable for deeply pitted ice-pick scars, and many patients pursue combination therapies (such as microneedling, laser, or fillers) to address different scar morphologies.

Contraindications and precautions: Absolute contraindications include active infection at the treatment site and known allergy to anesthetic agents. Considerations include bleeding disorders or anticoagulant use, keloid or hypertrophic scar tendencies, impaired wound healing, active herpes simplex infection near the treatment area, or immunosuppression. Caution is advised for darker skin types due to the risk of postinflammatory pigment changes.

Risks and outcomes: Possible adverse effects include transient bruising, swelling, tenderness, and mild discomfort. Rare complications include infection, irregular scarring, or pigmentary changes. Results vary by scar type and individual, and multiple sessions may be required for optimal improvement.