Chapter 61: Hypertrophic Scars, Keloids, and Acne Scars

INTRODUCTION

Hypertrophic scars and keloids are both characterized by excess fibrous tissue at a site of injury in the skin. Hypertrophic scars are confined to the original wound site, whereas keloids, by contrast, extend beyond the original wound site (Table 61.1). Both are common and frequently disturb patients greatly, both as an unsightly scar as well as a reminder of previous trauma or surgery. Acne scars result from the loss of underlying collagen and elastic tissue from dermal inflammation associated with acne, particularly cystic acne. Acne scars are also very common and a source of distress to the patient, both for their obvious appearance on the face as well as a reminder of previous acne.

HYPERTROPHIC SCARS AND KELOIDS: PHYSICAL EXAMINATION

Hypertrophic scars present as thick, firm linear plaques at the site of trauma. Initially, they may be erythematous but often become skin-colored with time. Keloids are firm, fibrous plaques that extend outside the site of injury with claw-like projections.

DIFFERENTIAL DIAGNOSIS

Dermatofibroma, scar sarcoid, dermatofibrosarcoma protuberans, granuloma.

LABORATORY EXAMINATION

None. If, however, a keloid is unresponsive to multiple therapies, skin biopsy to rule out dermatofibrosarcoma protuberans is indicated.

MANAGEMENT

There are multiple therapies that are effective for decreasing the unsightly appearance of keloids and hypertrophic scars. None is completely satisfactory and none can be designated as a treatment of choice. Patients should be educated as to the refractory nature of keloids and hypertrophic scars and that multiple treatments over months are typically required for efficacy. Keloids tend to be more resistant to therapy than hypertrophic scars.

These treatment options include intralesional triamcinolone acetonide, intralesional 5-fluorouracil (5-FU), silicone sheeting, imiquimod, radiation, elliptical excision, fractional resurfacing, and pulsed dye laser (PDL) (595 nm). These treatments provide different benefits. Some reduce erythema, others ...