Presentation is loading. Please wait.

Presentation is loading. Please wait.

Melasma. Biology of melanocyte Dendritic cell at basal layer of epidermis Dendritic cell at basal layer of epidermis Produce melanin and send to surrounding.

Similar presentations


Presentation on theme: "Melasma. Biology of melanocyte Dendritic cell at basal layer of epidermis Dendritic cell at basal layer of epidermis Produce melanin and send to surrounding."— Presentation transcript:

1 Melasma

2 Biology of melanocyte Dendritic cell at basal layer of epidermis Dendritic cell at basal layer of epidermis Produce melanin and send to surrounding keratinocyte Produce melanin and send to surrounding keratinocyte Epidermal melanin unit (melanocyte:keratinocyte) = 1:36 Epidermal melanin unit (melanocyte:keratinocyte) = 1:36

3 Biology of melanin Synthesis from melanosome Synthesis from melanosome Transport to keratinocyte via dendritic process of melanocyte Transport to keratinocyte via dendritic process of melanocyte 2 type 2 type : eumelanin : pheomelanin

4 Melanin synthesis Binding Melanocyte Melanocortin 1 stimulating hormone receptor adenylase cyclase adenylase cyclase Tyrosinase cAMP

5 Melanin synthesis Tyrosine tyrosinase tyrosinaseDopa Dopa quinone Eumelanin Pheomelanin

6 Melanin synthesis MSH MC1R mutation of MC1R Eumelanin Pheomelanin

7 Melanin transfer Phagocytosis Phagocytosis : melanin transfer to dermis : phagocytose by melanophage Endocytosis Endocytosis : melanin transfer to keratinocyte via intercellular space

8 Melasma Acquired bilateral symmetrical hypermelonosis Acquired bilateral symmetrical hypermelonosis Irregular light to gray brown macule and patch Irregular light to gray brown macule and patch Ill defined margin Ill defined margin Involved sun exposure area Involved sun exposure area Most common in women Most common in women

9 Melasma is a common acquired pigmentary disorder that occurs mainly in women (more than 90% of cases) of all racial and ethnic groups, but particularly affects those with Fitzpatrick skin types IV–VI Melasma is a common acquired pigmentary disorder that occurs mainly in women (more than 90% of cases) of all racial and ethnic groups, but particularly affects those with Fitzpatrick skin types IV–VI

10 Distribution of melasma Central facial pattern (63%) : cheek, forehead, nose, chin Central facial pattern (63%) : cheek, forehead, nose, chin Malar pattern (21%) : cheek, nose Malar pattern (21%) : cheek, nose Mandibular pattern (16%) :chin Mandibular pattern (16%) :chin

11 Cause of melasma Light : UVA, UVB, visible light Light : UVA, UVB, visible light Hormone : pregnancy, contraceptive pill Hormone : pregnancy, contraceptive pill Drug : dilantin, anti-malarial drug, tetracycline, minocycline Drug : dilantin, anti-malarial drug, tetracycline, minocycline Cosmetic : perfume, color Cosmetic : perfume, color Genetic Genetic Malnutrition : liver dysfunction, B12 def. Malnutrition : liver dysfunction, B12 def.

12 Type of melasma Epidermal melasma Epidermal melasma Dermal melasma Dermal melasma Mixed epidermal dermal melasma Mixed epidermal dermal melasma

13 The use of a Wood’s lamp can often be very beneficial in determining the location of melanin deposition showing enhancement of color contrast in lesional skin for the epidermal type, but not the dermal types. The mixed type has enhancement in some areas of lesional skin, but not in other areas.2 The use of a Wood’s lamp can often be very beneficial in determining the location of melanin deposition showing enhancement of color contrast in lesional skin for the epidermal type, but not the dermal types. The mixed type has enhancement in some areas of lesional skin, but not in other areas.2

14 Estrogen may play a role in melasma induction(OCP,HRT,pregnancy) Estrogen may play a role in melasma induction(OCP,HRT,pregnancy) Pregnancy induced melasma will recover after some months Pregnancy induced melasma will recover after some months

15 Epidermal melasma Light or dark brown color Light or dark brown color Melanin deposition in basal, suprabasal layer of epidermis Melanin deposition in basal, suprabasal layer of epidermis Larger melanocyte with more noticeable dendritic process Larger melanocyte with more noticeable dendritic process

16 Dermal melasma Blue gray color Blue gray color Perivascular melanophage at superficial and middermis Perivascular melanophage at superficial and middermis Melanin granule in dermis Melanin granule in dermis

17 Whether the melanin is deposited in the epidermis or dermis is important therapeutically because dermal hyperpigmentation is much more challenging to treat Whether the melanin is deposited in the epidermis or dermis is important therapeutically because dermal hyperpigmentation is much more challenging to treat

18 Postinflammatory Hyperpigmentation (PIH) PIH represents a pathophysiologic response to cutaneous inflammation, such as acne, atopic dermatitis, lichen planus, and psoriasis. Similar to melasma, it is more obvious in patients with brown or black skin. It has no gender or age predominance. PIH represents a pathophysiologic response to cutaneous inflammation, such as acne, atopic dermatitis, lichen planus, and psoriasis. Similar to melasma, it is more obvious in patients with brown or black skin. It has no gender or age predominance.

19 The lesions are characteristically limited to the site of the preceding inflammation and have indistinct, feathered borders.7 Melanocytes can either be stimulated by the inflammatory process to become hypertrophic, thus secreting more melanin, or the number of melanocytes can increase The lesions are characteristically limited to the site of the preceding inflammation and have indistinct, feathered borders.7 Melanocytes can either be stimulated by the inflammatory process to become hypertrophic, thus secreting more melanin, or the number of melanocytes can increase

20 . Epidermal hyperpigmentation (e.g., associated with acne) occurs when increased melanin is transferred to keratinocytes while dermal pigmentation (e.g., associated with lichen planus and cutaneous lupus erythematosus) occurs when the basement membrane is disrupted and melanin falls into the dermis and resides within melanophage. Epidermal hyperpigmentation (e.g., associated with acne) occurs when increased melanin is transferred to keratinocytes while dermal pigmentation (e.g., associated with lichen planus and cutaneous lupus erythematosus) occurs when the basement membrane is disrupted and melanin falls into the dermis and resides within melanophage

21 Therapeutic goals for hyperpigmentation include promoting the degradation of melanosomes, inhibiting the formation of melanosomes, and retarding the proliferation of melanocytes. Therapeutic goals for hyperpigmentation include promoting the degradation of melanosomes, inhibiting the formation of melanosomes, and retarding the proliferation of melanocytes.

22 Because sun exposure is an important etiologic factor in hyperpigmentation, all patients should use daily, broad-spectrum, high SPF sunscreens and minimize sun exposure. Because sun exposure is an important etiologic factor in hyperpigmentation, all patients should use daily, broad-spectrum, high SPF sunscreens and minimize sun exposure.

23 Effective therapy Retard melanocyte proliferation Retard melanocyte proliferation Inhibit melanosome formation Inhibit melanosome formation Promote melanosome degradation Promote melanosome degradation

24 Treatment Avoidance Avoidance Sunscreen Sunscreen Medication : hydroquinone, azelaic acid, retinoic acid Medication : hydroquinone, azelaic acid, retinoic acid Chemical peeling Chemical peeling Dermabrasion Dermabrasion Laser Laser

25 Topical Treatments for Melasma In those patients with epidermal type melasma, there are multiple treatments available (see Table 2).6 Topical agents include phenols, e.g., hydroquinone (HQ); retinoids, e.g., tretinoin; azelaic acid; kojic acid (KA); and glycolic acid (GA). In those patients with epidermal type melasma, there are multiple treatments available (see Table 2).6 Topical agents include phenols, e.g., hydroquinone (HQ); retinoids, e.g., tretinoin; azelaic acid; kojic acid (KA); and glycolic acid (GA).

26 hydroquinon 2%–4% has been widely used for melasma therapy. 2%–4% has been widely used for melasma therapy. inhibits the conversion of dopa to melanin by inhibitin theactivity of tyrosinase. inhibits the conversion of dopa to melanin by inhibitin theactivity of tyrosinase. may interfere with DNA and RNA synthesis, degrade melanosomes, and destroy melanocytes. may interfere with DNA and RNA synthesis, degrade melanosomes, and destroy melanocytes.

27 Reports of contact dermatitis in up to 25% Reports of contact dermatitis in up to 25% As an itchy eruption it is best to be tested in a hidden part before use it is best to be tested in a hidden part before use Side-effects included irritant and allergic contact dermatitis, PIH, nail bleaching and rarely, ochronosis-like pigmentation.

28 retinoids % % inhibiting tyrosinase transcription,interrupting melanin synthesis. inhibiting tyrosinase transcription,interrupting melanin synthesis. While tretinoin may be effective in reducing melasma, it typically takes at least 24 weeks to see clinical improvement. While tretinoin may be effective in reducing melasma, it typically takes at least 24 weeks to see clinical improvement.

29 azelaic acid 1)15%–20%) a C9 dicarboxylic acid, is a reversible inhibitor of tyrosinase 2) shown to be as effective as HQ 4% but without its side effects. 3) The combination of azelaic acid with 0.05% tretinoin or 15%–20% glycolic acid may produce earlier, more pronounced skin lightening. Adverse effects include pruritus, mild erythema, scaling, and burning.

30 KOJIC ACID KA 2% is generally equivalent to other therapies but may be more irritating. KA 2% is generally equivalent to other therapies but may be more irritating.

31 Glycolic acid GA 5%–10% is an alpha-hydroxy acid GA 5%–10% is an alpha-hydroxy acid. It decreases pigment by many mechanisms including thinning the stratum corneum, enhancing epidermolysis, dispersing melanin in the basal layer of the epidermis, and increasing collagen synthesis in the dermis.. It decreases pigment by many mechanisms including thinning the stratum corneum, enhancing epidermolysis, dispersing melanin in the basal layer of the epidermis, and increasing collagen synthesis in the dermis.

32 , HQ 5%, tretinoin 0.1%, and dexamethasone 0.1%, was first introduced in 1975 and termed the Kligman formula, HQ 5%, tretinoin 0.1%, and dexamethasone 0.1%, was first introduced in 1975 and termed the Kligman formula combination of HQ 4%, tretinoin 0.05%, and fluocinolone acetonide 0.01% (Tri- Luma®, Galderma) proved better than any combination of two of the above agents, with 77% of patients showing complete or nearly complete clearing combination of HQ 4%, tretinoin 0.05%, and fluocinolone acetonide 0.01% (Tri- Luma®, Galderma) proved better than any combination of two of the above agents, with 77% of patients showing complete or nearly complete clearing

33 Clinically significant improvement was noted as early as 4 weeks with maximum results at 8 weeks. Clinically significant improvement was noted as early as 4 weeks with maximum results at 8 weeks. The most common adverse effects were mild local irritation, erythema, and skin peeling The most common adverse effects were mild local irritation, erythema, and skin peeling GA peels to a topical regimen of HQ 2%, GA 10% and tretinoin 0.05% cream in PIH patients GA peels to a topical regimen of HQ 2%, GA 10% and tretinoin 0.05% cream in PIH patients

34 Laser treatment for melasma Target chromophore is melanin Target chromophore is melanin Should destroy melanocyte in hair follicle Should destroy melanocyte in hair follicle Good in dermal and mix melasma Good in dermal and mix melasma

35 Laser treatment for melasma Epidermal melanin removal : lPL, PDL Epidermal melanin removal : lPL, PDL Dermal melanin removal : Q-switched Ruby, Q-switched Alexandrite, Q-switched Nd:YAG Dermal melanin removal : Q-switched Ruby, Q-switched Alexandrite, Q-switched Nd:YAG Fraxel Fraxel

36 Epidermal melanin removal No recovery time No recovery time Repigmentation after removal Repigmentation after removal

37 Dermal melanin removal Minimal downtime Minimal downtime Side effect : transient erythema, hypopigmentation Side effect : transient erythema, hypopigmentation Repigmentation from melanin in melanophage Repigmentation from melanin in melanophage

38 Fraxel Epidermal and dermal ablation Epidermal and dermal ablation MEND formation and eliminated through skin MEND formation and eliminated through skin Induce melanophage disruption and release melanin granule into dermis Induce melanophage disruption and release melanin granule into dermis Downtime 3-7 d Downtime 3-7 d Long term improvement Long term improvement

39 Chemical peeling With AHA like TCA,Salycilic acid,and … With AHA like TCA,Salycilic acid,and …


Download ppt "Melasma. Biology of melanocyte Dendritic cell at basal layer of epidermis Dendritic cell at basal layer of epidermis Produce melanin and send to surrounding."

Similar presentations


Ads by Google