Comparative Study of a 1064-nm Fractional Picosecond Laser Versus IPL in Facial Rejuvenation

Blinded GSP scoring

Global skin photoaging score assessed by blinded dermatologists using the Global Skin Photoaging (GSP) Scale. Scale range: 0-4, where higher scores indicate more severe photoaging. The scoring criteria are defined as follows: 0: Smooth skin without visible wrinkles or pigmentary heterogeneity in cheeks, forehead, or perioral regions 1. Discrete focus of textural roughness, dyschromia, or fine lines in one facial region (cheeks/forehead/perioral) 2. Two distinct areas demonstrating textural roughness, dyschromia, or fine lines; OR concurrent manifestations (roughness + dyschromia + wrinkles) in one region 3. Three affected areas; OR concurrent manifestations in two regions 4. Photodamage exceeding grade 3 criteria

Time frame: baseline (before first treatment), before second treatment (approximately 4-6 weeks after baseline), before third treatment (approximately 8-12 weeks after baseline)

Regional Fine Line and Dyschromia Grading by Dermatologists

Fine lines graded on the Modified Fine Line Improvement Scale (-1 to 4: -1=worsening, 0=no change, 1=1-25% improvement, 2=25-50%, 3=50-75%, 4=75-100%; higher scores = greater improvement). Dyschromia graded on the Modified Dyschromia Improvement Scale (-1 to 4: -1=increased severity, 0=no change, 1=1-25% reduction, 2=25-50% reduction, 3=50-75% reduction, 4=75-99% reduction; higher scores = greater improvement).

Time frame: before second treatment (approximately 4-6 weeks after baseline), before third treatment (approximately 8-12 weeks after baseline), and 1 month after third treatment (approximately 12-16 weeks after baseline)

Quantitative Assessment of Skin Roughness Using C-Cube Imaging System

Skin surface roughness will be objectively quantified using the C-Cube high-resolution imaging system (Pixience, Toulouse, France). Standardized images will be captured from predefined facial regions (e.g., cheek or forehead) under consistent lighting and positioning conditions. Roughness values will be automatically calculated by the system's built-in analysis software. Measurements will be performed at baseline, second, third, and fourth follow-up visits to monitor treatment-induced changes.

Time frame: baseline (before first treatment), before second treatment (~4-6 weeks after baseline), before third treatment (~8-12 weeks), and 1 month after third treatment (~12-16 weeks)

Quantitative Skin Pigmentation and Erythema Assessment Using SkinColorCatch

Objective colorimetric measurements will be performed using the Delfin SkinColorCatch® device to quantify skin pigmentation and erythema in predefined facial regions. The following parameters will be recorded at each time point: Melanin Index (MI), L\* value (lightness), and Erythema Index (EI). Measurements will be obtained under standardized ambient lighting and positioning conditions at baseline, second, third, and fourth follow-up visits.

Time frame: baseline (before first treatment), before second treatment (~4-6 weeks after baseline), before third treatment (~8-12 weeks), and 1 month after third treatment (~12-16 weeks)

Transepidermal Water Loss (TEWL) Measurement Using Delfin Vapometer

Skin barrier function will be assessed by measuring transepidermal water loss (TEWL) using the Delfin Vapometer® device. Measurements will be taken at standardized facial sites under controlled environmental conditions (temperature and humidity) following device guidelines. TEWL values will be recorded at baseline and at the second, third, and fourth follow-up visits to evaluate changes in skin barrier integrity over the treatment course.

Time frame: baseline (before first treatment), before second treatment (~4-6 weeks after baseline), before third treatment (~8-12 weeks), and 1 month after third treatment (~12-16 weeks)

Standardized VISIA Photographic Documentation

Standardized facial photographs will be captured using the VISIA Complexion Analysis System (Canfield Scientific, USA) at each time point to document changes in skin appearance. The system will provide consistent image capture under controlled lighting and positioning conditions. VISIA documentation will support visual assessment of treatment-related changes in texture, pores, pigmentation, and overall skin condition. Images will be used for qualitative reference and supplemental analysis by blinded evaluators.

Time frame: baseline (before first treatment), before second treatment (~4-6 weeks after baseline), before third treatment (~8-12 weeks), and 1 month after third treatment (~12-16 weeks)

Incidence of Adverse Events

Adverse events (AEs) including erythema, edema, hyperpigmentation, hypopigmentation, burning sensation, pain, and scarring will be recorded following each treatment session and at each follow-up visit.

Time frame: before second treatment (~4-6 weeks after baseline), before third treatment (~8-12 weeks), and 1 month after third treatment (~12-16 weeks)