CL Goh, L Khoo
Correspondence: Dr C L Goh, nsc@pacific.net.sg
ABSTRACT
Objective To study the efficacy and complications from Unipulse CO2 laser resurfacing system (Nidek, California) for the treatment of scars and wrinkles in patients with Type III and IV skin type.
Methodology This is a prospective study of patients with skin type III and IV who received laser-resurfacing treatment for facial scars and wrinkles. All patients received topical tretinoin 0.025% cream at least two weeks prior to laser resurfacing. Laser resurfacing was carried out under lidocaine 1% nerve blocks with the Unipulse CO2 laser scanning system. The power at tissue was set at 15 watts (fluence = 6.12 J/cm2; spot size = 1.02 mm, frequency = 300 Hz), with a 20% overlap. Lesions around the eyes were resurfaced with one pass. Those on other parts of the face with two to three passes. Patients were assessed up to 12 months. Treatment response (assessed by patient and dermatologist) was graded as "no change" = no improvement, "minimal improvement" = <25% clearance, "moderate improvement" = 25-50% clearance,"good improvement" = 50-75% clearance and "excellent improvement" = >75% clearance. Complications (assessed by dermatologist only) including erythema, hypopigmentation and hyperpigmentation were scored subjectively as none, minimal, mild, moderate and severe.
Results 16 (nine females, seven males) patients were studied. Thirteen patients were treated for acne scars, two patients for wrinkles and one patient for chicken pox scar. Their mean age was 30.7 years (SD = 9.5 years). Fifteen patients had skin type IV and I had skin type III. TREATMENT RESPONSE: Thirteen patients were assessed at six weeks post laser treatment. One (8%) patient had "minimal improvement" (<25%) improvement, 10 (77%) patients had "moderate improvement" (25-50%) and 2 (15%) patients had "moderate improvement" (50-75%) improvement. At six months, 37% had "minimal improvement", 37% had "moderate improvement" and two had "good improvement and one patient with fine wrinkles had "excellent improvement".
Complications All patients experienced severe erythema at Day 1. Erythema faded over six months. By three months only 22% had minimal erythema and by six months none had erythema. Moderate pigmentation developed in 15% at six weeks. At three months 33% had varying degree of pigmentation. At six months one (12%) patient had residual pigmentation. Only one patient developed mild minimal hypopigmentation at six month, which cleared at 12 months. Another patient developed hypopigmentation at 12 months.
Conclusion CO2 laser resurfacing provides minimal to moderate improvements for scars and wrinkles among Asians with darker skin type. Erythema fades over six months after resurfacing. Post-inflammatory pigmentation is common but tends to clear over six months.
Keywords: Acne scars, wrinkles, cosmetic laser-surgery
Singapore Med J 2002; 43(1): 28-32