Table 1.
Irradiation | Variable | Facial melasma |
Normal adjacent skin |
p (time × group)** | ||||
---|---|---|---|---|---|---|---|---|
Pre | Post | p* | Pre | Post | p* | |||
UVB | MelBasal | 64 (60–65) | 65 (65–68) | <0.01 | 54 (53–56) | 56 (55–62) | <0.01 | 0.09 |
MelUD | 44 (30–77) | 45 (38–97) | 0.24 | 44 (32–71) | 67 (41–87) | 0.04 | 0.84 | |
Dendrites | 6 (2–8) | 10 (8–18) | <0.01 | 6 (3–14) | 11 (7–16) | 0.05 | 0.59 | |
GranMelanos | 2.0 (1.5–2.1) | 1.6 (1.3–2.0) | 0.11 | 1.9 (1.4–2.0) | 1.9 (1.6–2.0) | 0.80 | 0.98 | |
UVA | MelBasal | 62 (54–66) | 70 (57–72) | <0.01 | 56 (49–61) | 57 (50–63) | <0.01 | 0.06 |
MelUD | 41 (18–88) | 86 (36–144) | 0.05 | 45 (27–90) | 74 (34–204) | 0.50 | 0.88 | |
Dendrites | 8 (4–11) | 8 (2–22) | 0.92 | 3 (2–5) | 5 (3–9) | 0.26 | 0.53 | |
GranMelanos | 1.0 (1.0–1.8) | 2.0 (1.8–2.1) | 0.05 | 1.3 (1.3–2.0) | 1.3 (1.1–1.9) | 0.34 | 0.03 | |
Visible light | MelBasal | 73 (59–74) | 75 (69–80) | <0.01 | 64 (56–66) | 70 (61–75) | <0.01 | 0.09 |
MelUD | 62 (54–72) | 52 (45–83) | 0.11 | 66 (59–83) | 75 (53–127) | 0.34 | 0.21 | |
Dendrites | 2 (1–4) | 4 (2–14) | 0.11 | 1 (0–3) | 4 (1–5) | 0.06 | 0.38 | |
GranMelanos | 1.4 (1.0–2.0) | 1.5 (1.0–2.3) | 0.11 | 1.5 (1.0–2.0) | 1.5 (1.0–2.0) | 0.80 | 0.98 |
MelBasal, percentage of melanin in the basal layer of the epidermis; MelUD, percentage of melanin in the upper dermis (×100); GranMelanos: granulation score of melanosomes of the epidermis (1+, fine granulation; 2+, moderate granulation; 3+, coarse granulation), mean of four fields.
p-value, pre vs. post (adjusted by phototype).
p-value, melasma vs. normal adjacent skin depending on the response to irradiation (adjusted by phototype).