الفهرس 
MelasmaOnly 14 pages are availabe for public view
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Abstract
Melasma is a common disorder of macular facial
hyperpigmentation, which can also affect the neck, namely
sun-exposed areas. It usually affects females during
childbearing age, but Melasma may also appear in 14%-
25% of male population, more commonly affecting Indian
males.
Melasma was been reported during pregnancy
however many other factors have been implicated in the
etiology of melasma such as genetic predisposition with
increased incidence among family members. Also UV light
was believed to be an initiating factor for melasma due to
its known effect on melanogenesis. Hormonal influence
had its share in literature as it was reported that estrogen
receptor expression increases in melasma affected skin.
Many patients noticed melasma appearance after long time
use of hormonal contraception.
Other associations of melasma include certain
cosmetic use, chronic Pelvic inflammatory disease
especially due to Chlamydia trachomatis and co-existence
of lentigines and melanocytic nevi. Lesions of melasma are irregular light to dark brown
macules with different patterns of distribution including
centrofacial pattern, malar pattern, mandibular pattern and
other less common areas such as extensor forearm and
shoulders. Melasma is classified according to Wood’s lamp
examination into epidermal, dermal, mixed patterns and
indeterminate pattern.
Histopathologically, melanin distribution is mainly in
the basal and suprabasal layers. Severe solar elastosis was
also found in some patients, and greater number of
epidermal melanocytes were reported which were more
active than their counterpart in perilesional skin.
Melasma should be differentiated from
postinflammatory hyperpigmentation and other causes of
facial melanosis.
Treatment includes general measures such as the
proper use of sun screen and avoidance of sun exposure and
cessation of hormonal contraception if used. Specific
treatment includes topical therapy such as hydroquinon,
topical retinoids or topical steroids. Combined topical
treatment has proven its effectiveness for persistent types of
melasma. Azelaic acid, kojic acid and ascorbic acid were
previously introduced in literature for melasma treatment. Chemical peeling is an effective method of melanin
removal using GA, SA or TCA. Other treatments include
dermabrasion, intense pulsed light therapy, laser therapy,
fractional resurfacing, and mesotherapy.
Treatment of melasma is challenging due to
resistance to respond and high incidence of recurrence after
discontinuation of therapy. Thus, application of combined
treatment modalities and use of maintenance therapy after
resolution has always been mandatory.
On the basis of both visible light and Wood’s light
examination, we detected 3 types of melisma in our study.
Epidermal type exhibited enhancement of color contrast
when examined with Wood’s light as compared to visible
light and were observed in 60% of patients. Dermal type of
melasma exhibited no enhancement or accentuation of
color contrast under the Wood’s light observed in 30% of
patients. Lastly the mixed type of melasma refers to those
patients in whom Wood’s light examination revealed both
enhancement of lesions in some areas and no enhancement
of lesions in other areas that was observed in 10% of
patients.
Interestingly, by histopathological examination, 7
patients had epidermal melasma. When these patients were
examined by Wood’s light 4 of them showed epidermal melasma, 2 of them had dermal melasma and 1 of them had
mixed melasma.
On the other hand, by histopathological examination,
1patient had dermal type of melasma, but the Wood’s light
examination of the same patient showed evidence of
epidermal type of melasma.
Additionlly, the histopathological examination of 2
of the patients showed mixed type of melasma.
Alternatively, Wood’s light examination of them showed
that one of them had epidermal type of melasma while the
other had dermal type of melasma.
Only in 4 patients (40%) there was agreement
between the histopathologic and the Wood’s light results.
So, our results denote that Wood’s light correlates poorly
with histopathological type of melasma. We recommend
further studies to assess the role of Wood’s light in fair
colored skin and in large series studies.