Periorbital Hyperpigmentation : Overcoming the Challenges in the Management

Periorbital hyperpigmentation, also referring as dark circles or periorbital melanosis, is not a medical problem but can be a significant cosmetic concern for a large number of individuals and they try to find a treatment for this condition. This condition affects individuals in a wide range of ages, both sexes and all races. The therapeutic approach must vary with cause as it is multifactorial. Possible causes include excessive pigmentation, volume loss, skin laxity, tear trough, increased prominence and density of subcutaneous vasculature and orbital structural problem. Treatment modalities include topical bleaching agents, chemical peeling, and lasers, injectable fillers, fat transfer, high intensity focused ultrasound and surgery as monotherapy or in combination therapy to target the contributing factors of periorbital hyperpigmentation.


Introduction
P eriorbital hyperpigmenta on (POH) is a common dermatological condi on, which is also known as periorbital melanosis, periocular hyperpigmenta on, dark circles under the eyes (DC), infraorbital discolora on, infraorbital darkening, or idiopathic cutaneous hyperchromia of the orbital region. 1,2It presents as bilateral, homogeneous hyperchromic macules and patches primarily involving the lower eyelids but also some mes extending towards the upper eyelids, eyebrows, malar regions, temporal regions and lateral nasal root. 3This condi on aff ects individuals with a wide range of age, both sexes and all races. 4The age of onset is usually a er puberty or in early adulthood (16-25 years).Females are frequently aff ected by POH because of either of the two reasons:1) More cosme cally concern and 2) Greater dermal vessels conges on and stasis related extravasa on during menstrual cycles.
POH is a condi on that does not cause morbidity but it makes the individuals look red, sad, or hung over. 1 There is popular demand for treatment of POH which is judged by the amount of adver sing of cosme cs marketed to treat this condi on.It is a cosme c concern for a large number of individuals especially women who are really bothered and concerned about it and rela ng it with signifi cant impairment on their quality of life. 5Concealing the lesions is almost mandatory for some individuals who depend on a well-cared and posi ve appearance for their work or social ac vi es. 3 Despite pa ents with POH o en seen by the dermatologists, there is not much a en on received in the dermatology literature.There are only a few published studies on its prevalence, causes, pathogenesis and evidence-based treatment modali es.The aim of the review is to highlight the clinical approach to a case of POH for the management. http://dx.doi.org/10.3126/njdvl.v16i1.19411

Gene c
Periorbital hyperpigmenta on is considered to have a gene c basis. 2 It is more dis nct in Mediterranean ethnic group and is also o en seen in mul ple members of the same family. 3cessive pigmenta on Excessive pigmenta on is seen in POH because of dermal melanocytosis and post infl ammatory hyperpigmenta on secondary to atopic derma s or allergic contact derma s.In allergic individuals (atopic and allergic contact derma s) frequent causes are due to rubbing or scratching the skin around the eyes and accumula on of fl uid due to facial allergy.3 Excessive pigmenta on can also be due to post infl ammatory hyperpigmenta on secondary to other dermatological condi ons (e.g., lichen planus pigmentosus) and can be drug induced.7 According to Gathers 8 chronic use of a few drugs such as hormone-replacement therapy, oral contracep ves, an psycho cs, chemotherapeu c compounds, gold can cause periorbital hyperpigmenta on.
Dermal melanocytosis can be due to congenital and environmental causes, which is histologically characterized by the presence of melanocytes in the dermis.Clinically, these lesions are iden fi able by the dis nc ve grey or blue-grey appearance. 2 Nevus Ota if infraorbitally located, it can be a cause of periorbital hyperpigmenta on. 1 Similarly, nevus of Hori may extend to involve the periocular area, causing POH. 2 Environmental causes that result in dermal melanocytosis include excessive sun exposure and drug inges on. 1

Periorbital edema
The eyelid region appears to have a 'sponge' property, which can help in the accumula on of fl uid in systemic or local edema causes.An eyelid fl uid deposit is characterized by its worsening in the morning or a er a salty meal, the purplish color, and the undefi ned outlines of the regional fat complements. 9nimal subcutaneous fat, thin skin and superfi cial loca on of vasculature Another important cause of POH may be due to the minimal infraorbital subcutaneous fat, superfi cial loca on of the orbicularis oculi muscle, and thin, translucent skin of the lower eyelid.This may lead to a violaceous appearance due to the visible prominence of the subcutaneous vascular plexus or vasculature contained within the muscle. 10It is more prominent in the inner aspect of the lower eyelids and is usually accentuated during episodes of physical and mental stress including menstrual period and pregnancy and thus may worsen periorbital hyperpigmenta on. 1

Orbital structural problem
Advancing age related anatomic changes of the midface so ssue include subcutaneous fat atrophy and volume loss, hypertrophy of orbicularis oculi muscle, pseudohernia on of suborbicularis oculi fi broadipose ssue and volume loss in the malar region.These features further the appearance of the POH.

Skin laxity and tear trough (Shadowing eff ect)
Shadowing due to the skin laxity and tear trough is another cause of POH.These are the result from a combina on of advancing age and chronic photodamage.Over me, collagen and elas n in the thin ssue of the eyelids and periorbital skin undergo degenera on. 11In addi on, the damaged epidermis releases collagenases also contribute to degenera on of collagen and therefore the skin laxity confers a shadow eff ect on the lower eyelids.The tear trough is a depression centered over the medial side of the inferior orbital rim.It deepens as the pa ent ages because infraorbital fat is displaced anteriorly due to the loss of periorbital subcutaneous fat with thinning of the skin over the orbital rim ligament that confers hollowness to the orbital rim area 9 along with pseudohernia on of the infraorbital fat that accentuate the shadowing eff ects.This shadowing eff ects is light dependent, o en masked with the use of direct fl ash photography. 12her causes Drugs: Ocular hypotensive eye drops drugs as prostaglandin analogues (latanoprost and bimatoprost, travoprost etc.) can also cause periorbital hyperpigmenta on a er 3-6 months of treatment. 13he possible mechanisms of the pigmenta on are increased melanogenesis in dermal melanocytes and increased transfer of melanin to basal epidermis, though rare, but an acquired orbital lipodystrophy may develop owing to the potent an androgenic eff ects of prostaglandin F2. 14 Underlying systemic, metabolic, hormonal disorders: It has been found that certain underlying systemic, metabolic, hormonal diseases, nutri onal defi ciencies may lead to pigmenta on of the periorbital area, however no substan al evidenced in the literature. 15fe style factors: Some life style factors such as sleep disorders, stress, alcohol consump on, smoking, frequent cosme c use, frequent eye rubbing and lack of correc on for errors of refrac on like myopia are also implicated to POH although not clinically substan ated. 16

Clinical Features
Clinically, POH is characterized by light to darkcolored, brownish black pigmenta on surrounding the eyelids.It may present as a curved band of brownish to black pigmenta on on the skin of the lower eyelids approxima ng the shape of the orbital rim with frequent involvement of the upper eyelids or it may present as irregular patches of brownish or grey pigmenta on on the skin on the upper, lower or both eyelids with features of lichenifi ca on, accentua on of skin creases, and eczematous papules or patches in the surrounding areas.Some mes it presents as erythema predominantly involving the inner aspect of the lower eyelids, with prominent capillaries or telangiectasia (capillaries) or the presence of bluish discolora on of the lower eyelid and visible bluish veins that becomes more prominent when the overlying skin is stretched. 17

Evaluation
The diagnosis of periorbital hyperpigmenta on is mainly clinically, however, a thorough history and clinical assessment is necessary to iden fy the contribu ng e ologic factors and thus provide the targe ng therapies for an individual pa ent of POH.
A detailed history including dura on of the condi on, family history, history of atopy or drug intake, associated faulty habit or lifestyle, use of cosme cs, precipita ng factor such as photosensi vity, allergies, seasonal varia ons, presence of associated other cutaneous disorder in other areas of the face and presence of any concomitant illness such as anemia, gastrointes nal diseases, hepato-biliary diseases, renal diseases, thyroid diseases, etc. should fi rst be elicited.
The cutaneous examina on should be evaluated to detect the involvement of eyelids, extend beyond the periorbital region, color of hyperpigmenta on, presence of any dermatological disease or scar in the periorbital region, presence of any visible bulging, skin laxity, tear trough, superfi cial visible vasculature (i.e., capillaries or veins) in the infraorbital region, pallor in palpebral conjunc va, presence of pigmenta on in other areas a er washing the face with soap and water.
The pa ent must be examined under the direct light to iden fy the POH due to shadow eff ect.Tear trough gets accentua on with hard light from direct fl ash digital photography while masking with 45-degree so light from a strobe light source.The medial and central aspects of the tear trough may be accentuated with an upward gaze, whereas the lateral border may be accentuated with an upward outward gaze contralaterally. 18 possible, ask the pa ent to provide the prior photographs that can help to dis nguish the normal anatomic varia on from age-related changes.

Eyelid stretch test
Eye lid stretch test or manual stretching of the lower eyelid skin can help to diff eren ate between true pigmenta on and shadowing eff ect.Although the former retains its appearance with stretching, the la er improves or resolves en rely.if the violaceous hyperpigmenta on on manual stretching of the lower eyelids is worsen, then it is because of subdermal vascularity. 14od's lamp examina on Some mes, there may be a problem in diff eren a ng brown or blue purple hue in mixed type of POH because the blue hue may be missed at fi rst site due to hyperpigmented background that's when wood's lamp examina on is done to diff eren ate between the epidermal and dermal pigmenta on. 19The varia ons in epidermal pigmenta on become more apparent under Wood's light.For dermal pigmenta on, this contrast is less pronounced 2 .The Wood's lamp is also assisted in the diff eren a on of the pigmented (P) and mixed (M) types from the vascular type (V) of POH.However, there is no change in vascular, structural and vascular-structural of mixed type. 21her tests that are useful in the diagnosis of periorbital hyperpigmenta on are dermatoscopy, histopathology and imaging.

Dermatoscopy: It is a noninvasive diagnos c technique
for the in vivo observa on of pigmented skin lesion allowing a be er visualiza on of surface and subsurface structures and being easy and feasible to use.It can be used to diff eren ate the type of POH whenever there is doubt while examining with naked eyes.The dermatoscopic fi ndings of POH are-a) Vascular type: diff use erythema pa ern or mul ple thin blood vessels or diff use vascular network, b) Pigmented type: a pa ern of mul ple dots with diff erent sizes and colors or a diff use network of pigments and c) Mixed type: Combina on of vascular and mixed type. 21stopathology: Histopathologic evalua on of epidermal characteris c, increase melanocytes pigmenta on in the epidermis itself and increase in dermal melanocytes or pigmenta on is the gold standard for a be er understanding of the underlying e opathogenesis. 22However, it has certain limita on in the form of development of scar at the site of the biopsy, which may be a concern for the pa ent.
Imaging: imaging with VISIA system (Canfi eld Scien fi c, Inc, Fairfi eld, NJ) can highlight blood vessels and pigmenta on with UV light and cross-polarized fl ash photography Digital photography: Standardized, high-quality pretreatment and pos reatment digital photography with appropriate light is needed for the assessment of the treatment response.

Clinical Pattern Classifi cation of POH
The classifi ca on of diff erent pa erns and severity score of POH are important in introducing the therapeu c modali es on the basis of POH type, as diff erent types of POH respond to diff erent types of treatment.

Ranu et al in 2011 classifi ed Periorbital hyperpigmenta on on the basis of four parameters:
Color pa ern, boundaries, skin texture, associated skin disorders on and around the eyelids in order to determine the primary cause of POH. 17 a.Cons tu onal -The presence of a curved band of brownish to black pigmenta on on the skin of the lower eyelids approxima ng the shape of the orbital rim with frequent involvement of the upper eyelids.b.Post infl ammatory -Presence of irregular patches of brownish or grey pigmenta on on the skin on the upper, lower or both eyelids with features of accentua on of skin creases, lichenifi ca on and eczematous papules or patches in the surrounding areas.Personal and/or family history of atopy may or may not be present.c.Vascular -Presence of erythema predominantly involving the inner aspect of the lower eyelids, with prominent capillaries or telangiectasia (capillaries) or the presence of bluish discolora on of the lower eyelid and visible bluish veins that becomes more prominent when the overlying skin is stretched.This type of dark circle appears to be due to a combina on of transparency of the overlying skin and dermal vascularity.d.Shadow eff ect -Presence of a dark shadow under an overhanging tarsal muscle, eye bags, or the presence of a deep tear trough over the medial aspect of the inferior orbital rim, which disappear with direct light.e.Others -POH from other causes, including anemia, hormonal disturbances, nutri onal defi ciencies, acanthosis nigricans, skin laxity, associated chronic illness, habits, etc.
Recently Huang et 20 proposed a classifi ca on on the basis of clinical pa ern of pigmenta on and vasculature as the hue of POH poten ally indicates its cause and pathogenesis and can be well prac ced in clinical consulta on.The Periorbital hyperpigmenta on is classifi ed into pigmented type (brown color), vascular type (blue/pink/purple color with or without periorbital puffi ness), structural type (skin color structural shadows formed by facial anatomic surface contours due to loss of fat or so ssue volume with bony prominence that disappear a er illumina ng with front light), and mixed type (combines two or three of the above appearances).The mixed type of dark eye circle includes four subtypes as pigmentedvascular (PV), pigmented-structural (PS), vascularstructural (VS), and a combina on of the three (PVS).

POH Severity Assessment
Severity score of POH is done in comparison to the surrounding skin and has been scored as 0 -skin colour comparable to other facial skin areas, 1 -faint pigmenta on of infraorbital fold, 2 -pigmenta on more pronounced, 3 -deep dark color, all four lids involved and 4 -grade 3+ pigmenta on spreading beyond infraorbital fold. 15

Association of other Pigmentary Conditions with POH
There are various condi ons, which may be associated with periorbital hyperpigmenta on such as pigmentary line of demarca on, Acanthosis nigricans, melasma, Erythema dyschromicum perstans, fi xed drug erup on, ecchymosis, amyloidosis, dermatomyosi s etc.Therefore, these underlying health issue must be evaluated prior to formula ng a treatment plan for the POH.

Treatment
Despite a great number of available medica ons and therapies to a enuate periorbital hyperpigmenta on, there is lack of evidence-based studies to support their use. 1 Periorbital hyperpigmenta on is o en refractory to the treatment.Therefore, the pa ent may be treated either as monotherapy or in combina on therapy targe ng the contribu ng factors.These include bleaching creams, topical re noic acid, chemical peels, platelet rich plasma therapy, lasers and light therapy, so ssue augmenta on by autologous fat injec on and hyaluronic acid so ssue fi llers, micro-focused ultrasound therapy and surgery.

General measures
Sun protec on is a cornerstone of therapy.It is essen al by avoiding peak hours of sunlight (in the tropics, between 11 AM 4 PM), using shady side for ac vi es and making use of sunshades like parasols and broad brimmed hats.Use of opaque sunscreens containing zinc oxide, 10% (and SPF of 30) have the dual benefi t of camoufl aging and preven ng photoinduced darkening.
Cosme c camoufl age may be used during treatment to improve the quality of life.

Topical Applications
Topically applied products are the most suitable treatment to start with for the majority of pa ents. 23hese have been considered to improve the blood circula on and/or reduce melanin.Bleaching agents may be used as a monotherapy or combina on therapy with other procedures.The most bleaching agents inhibit tyrosinase ac vity, inhibit DNA synthesis in hyperac ve melanocytes, reduce the epidermal content of melanin, and thickening of the epidermis. 24e various topical bleaching agents are hydroquinone, kojic acid, a triple combina on, azelaic acid, arbu n, topical vitamin C. Out of these topical agents the most widely used is hydroquinone, used in a strength of 2% to 6% with the eff ect of treatment being evident a er 5 to 7 months of treatment.Some mes, it is associated with fewer side-eff ects like mild skin irrita on, itching, transient hypochromia, post-infl ammatory hyperpigmenta on.
Triple combina on (hydroquinone, tre noin and steroid), though available in the market in various combina on and is being used for the treatment of melasma and other pigmentary condi ons, there is no evident based study on its use in the POH.Kojic acid is a natural occurring fungal deriva ve produced by aspergillus species and penicillium species, has been tried in trea ng POH anecdotally in a concentra on ranging from 1 to 4% and has been found to be eff ec ve with side-eff ects like erythema and contact derma s though there are no studies yet.
Azelaic acid was ini ally developed for trea ng acne but because of its eff ect on tyrosinase and further with no development of leukoderma and exogenous ochronosis on prolonged use, it has been used for facial post-infl ammatory hyperpigmenta on and thus it is a poten ally promising agent for periocular hyperpigmenta on due to post-infl ammatory hyperpigmenta on.
Arbu n is an extract of leaves from bearberry shrub and cranberry, pear or blueberry leaves has been found eff ec ve in trea ng melasma.So, it can be used in other hyperpigmenta on including POH but with cau on as high doses may lead to hyperpigmenta on.It is available in a concentra on of 3%.Topical vitamin C is an an oxidant that scavenges free oxygen radicals in aqueous compartment which triggers melanogenesis and promotes collagen produc on and conceals color of blood stasis, which improves the appearance of POH.But as ascorbic acid is unstable, esterifi ed deriva ves in the form of L-ascorbic acid, 6-palmitate and magnesium ascorbyl phosphate are used. 2Ohshima and colleague 25 studied 14 subjects with dark circles of the lower eyelids and applied sodium ascorbate 10% or ascorbic acid glucoside 10% in a split faced manner for 6 months.They conclude that sodium ascorbate may improve dark circles by thickening the eyelid dermis and concealing dark colora on due to congested blood but there was no change in the melanin index.

Chemical peels
Chemical peels may be used alone or in combina on with topical bleaching agents.Glycolic acid is the most widely used alpha hydroxy acid for chemical peeling.Glycolic acid 20% can also be used for periorbital hyperpigmenta on however higher concentra on should be avoided to remove melanin from dermis.This may lead to dyspigmenta on and scarring as the skin is thin in this area.Lac c acid 15% has been used in periorbital hyperpigmenta on in combina on with trichloroace c acid (TCA) 3.75% every week for four treatments and it was found that almost all the pa ents showed signifi cant esthe c improvement. 26For treatment of POH in medium to darker skin, it is best to extend the peel to the en re face to avoid post-peel demarca on.For op mal outcome, pretreatment with a tre noin and hydroquinone bleaching agent for 2 to 4 weeks is recommended before undergoing a chemical peel.The most disturbing side eff ect of chemical peels can be post-infl ammatory hyperpigmenta on.This may be minimized with the help of priming agents, such as hydroquinone and tre noin.

Lasers
Periorbital hyperpigmenta on has been successfully treated with various lasers that target pigment, vascularity and skin laxity and tear trough.

Q-switched lasers
Q-switched lasers with nanosecond (and recently picosecond) pulse dura ons and wavelengths within the absorp on range of melanin are useful for targe ng the pigmenta on in POH.The typical clinical endpoint of these treatments is immediate lesion whitening without pinpoint bleeding.Lower energy se ngs should be used ini ally to minimize the occurrence of PIH. 3

Q switched ruby lasers (QSRL)
Rapid delivery of high-intensity energy at the 694-nm wavelength of QSRLs is moderately absorbed by melanin but poorly absorbed by hemoglobin, which disrupts melanosomes within kera nocytes, melanocytes, and melanophages and is considered as fi rst-line treatment for both dermal and epidermal pigmenta on in Fitzpatrick skin types I-II.
QRSL treatment is performed with 2 to 4 J/cm 2 using a 5-mm spot size (or varied accordingly) at 1.5 Hz.Watanabe et al 27 showed good response in infraorbital hyperpigmenta on a er 1 to 5 treatments sessions with the Q switched ruby laser (694nm).Combining Q switched ruby laser (694nm) with a bleaching agent containing 0.1% tre noin and 5% hydroquinone has also led to signifi cant improvement in this site.The purpose of this treatment is to improve epidermal pigmenta on by accelerated discharge of epidermal melanin by tre noin and suppressing new epidermal melanogenesis by hydroquinone cream. 28

Q switched alexandrite lasers (QSAL)
The Q-switched alexandrite laser (755-nm wavelength) penetrates deeper with a lower absorp on coeffi cient for melanin and is emi ed over a longer pulse dura on (50-70 ns) than that of QSRL, which may serve to decrease adverse events (eg, PIH) in dark-skinned pa ents as a result of milder melanosomal hea ng.Fitzpatrick skin types of IV or lower are performed with 3-to 5-mm spot sizes and 4 to 8 J/cm 2 .Lower fl uences may lead to equal effi cacy with decreased PIH. 29switched Nd-YAG lasers Q switched Nd-YAG laser with a wavelength of 1064 nm allow for much deeper energy penetra on and minimal melanin absorp on compared with QSRL or QSAL.Therefore, Fitzpatrick skin types V and VI can be treated with minimal risk of pos reatment dyspigmenta on.In a study conducted by Xu et al 30 in thirty Chinese female pa ents with under-eye circles, 8 low-fl uence treatments (3.5-mm spot size, 4.2 J/ cm 2 , 2 passes) at 3-to 4-day intervals showed a mean global improvement of 50% to 75% at 3 and 6 months, and 93.3% subjects reported good to excellent results without signifi cant adverse events.

Pulsed-Dye Lasers
Pulsed-dye lasers (585 and 595 nm wavelengths and pulse widths less than or equal to 40 ms) allow for selec ve photothermolysis of larger, deeper ecta c vessels and a far greater purpuric threshold. 31Dark skinned pa ents should be treated with longer pulse dura ons and lower fl uences.Treatment endpoint is immediate vessel spasm and transient purpura indica ve of intravascular coagula on.Care should be taken when using cryogen cooling, because the cryogen is likely to enhance PIH.
Pulse stacking and mul ple passes at subpurpuric fl uences with adequate epidermal protec on (cryogen or convec on cooling) lead to signifi cant improvement in vessel clearance without added adverse events, but mul ple treatment sessions may be needed.Superfi cial telangiectasias are treated with pulse dura ons and fl uences of 6 ms and 7 to 9 J/cm 2 (less than 0.6 mm) or 10 ms and 8 to 12 J/cm 2 (greater than 0.6 mm) using a 7-mm spot size, with marginally overlapping pulses.Thicker facial vessels require 20 to 40 ms pulse widths and sub-purpuric fl uences as high as 13 to 15 J/cm 2 .One to 3 sessions at 4-to 8-week intervals are o en needed.

Long-pulsed Nd-YAG Lasers
Long-pulsed 1064 nm Nd:YAG lasers are ideal for the treatment of larger, deeply situated facial vessels (eg, re cular veins) due to the more penetra on of laser energy at this wavelength.Fitzpatrick skin types V and VI can be treated with low risk of epidermal injury NJDVL.Vol 16, No.1, 2018 because of the low absorp on coeffi cient for melanin at 1064 nm.Treatment parameters for periorbital veins are based directly on vessel size and a 3.5-mm (range, 2 to 10) spot size; 1-mm re cular veins are treated with a 25-ms pulse dura on and fl uences of 160 to 190 J/ cm 2 , whereas 1-to 3-mm veins require up to 50 ms and 190 to 210 J/cm 2 .Vessel spasm or thrombosis is the endpoint of treatment, demonstrated by immediate vessel blanching or darkening.
In a study, twenty-six Chinese subjects with undereye dark circles having prominent re cular veins (1.0 to 2.5 mm) were treated with a 6-mm spot size, 120 to 140 J/cm 2 fl uence, and 6-to 10-ms double-pulsing with a 20-ms delay at monthly sessions using a contact cooled long-pulsed Nd:YAG laser. 32At 12-month followup, all subjects were found to have complete vessel resolu on.A retrospec ve study confi rmed nearly 100% subjec ve and objec ve improvement a er 1 to 2 sessions with appropriate se ngs.

Abla ve Tradi onal and Frac onal Lasers Tradi onal Abla ve Lasers
Pulsed CO 2 and erbium: YAG lasers preferen ally absorbed by water, leading to confl uent epidermal vaporiza on and thermal damage of the superfi cial dermis, leads to contrac on and denatura on of collagen.Alster and Bellew 33 treated 67 pa ents with dermatochalasia and periorbital rhy des using CO 2 laser resurfacing and found a signifi cant improvement.

Abla ve Frac onal Lasers
Frac onated lasers create columnar microthermal treatment zones, which leave up to 95% of the cutaneous surface intact and thus provide an endogenous reservoir for rapid healing and barrier to infec on.Signifi cant improvement in deep wrinkles, fi ne lines, texture irregularity, laxity, and dyschromia can be achieved with a single treatment.Tierney and colleagues 34 treated twenty-fi ve subjects with lower eyelid laxity with 2 to 3 sessions of abla ve frac onal resurfacing (AFR) using a CO 2 laser (25% coverage, 30 W, 1-ms dwell me).A mean improvement of 65.3% and 62.1% in laxity and rhy des, respec vely were found at 6-month follow-up.However, abla ve lasers are associated with greater discomfort, side eff ects, a weeklong down me, and an intense postopera ve care.

Non-abla ve Frac onal Lasers (NAFR)
NAFR laser causes dermal coagula on necrosis limited to microthermal treatment zones eventua ng in collagen remodeling but spares the overlying epidermis, leading to rapid recovery and reduced adverse events a er the procedure A study by Sukal and colleagues 35 found 50% to 100% improvement in eyelid skin ghtening in 55% of subjects a er 3 to 7 sessions (17 to 20 mJ, 500 to 750 microthermal treatment zones per cm 2 ) with a 1550-nm NAFR.

Intense Pulsed Light (IPL)
IPL can be used for periorbital pigmenta on and vascularity.For telangiectasia and re cular veins in infraorbital area, minimal pressure should be applied against the skin with the hand piece to avoid compression of target vessels.A typical pa ent requires 1 to 3 sessions to achieve signifi cant improvement, with subsequent semiannual maintenance treatments.
Inappropriate use of lasers and light in periorbital area may result in eye problems, including blindness, dryness and photophobia.Therefore, safety should be emphasized when trea ng periocular area with lasers and light by the use of proper eyewear (eye shields). 1

Soft tissue augmentation by autologous fat transplantation and soft tissue fi ller
The violaceous appearance of POH which is due to li le or no subcutaneous fat is treated by using autologous fat transplanta on or so ssue fi ller.

Autologous fat transplanta on
It is a technique by which fat ssues are removed from other parts of the body, usually thigh, bu ock, belly by liposuc on and then the ssues are processed into liquid and injected into the lower eyelid skin overlying the orbicularis oculi muscle.Roh and Chung 1 treated 10 pa ents with infraorbital dark circles due to increased vascularity and translucency of the skin by at least one autologous fat transplanta on, and followup evalua ons was done at least 3 months a er the last treatment.These pa ents showed an average of 78% improvement.

Fillers
Hyaluronic acid gel is used as a fi ller for threedimensional reshaping of periorbital complex.The ease of use, minimal incidence of complica ons and lack of down me associated with this product makes it nearly ideal for trea ng infraorbital volume loss.Though, pa ent sa sfac on is high, some pa ents may get darker pigmenta on a er hyaluronic acid gel.
Bosniak et al, 36 treated 12 pa ents with POH, tear trough deformity, or prominent nasojugal groove with the hyaluronic acid push technique.All pa ents experienced immediate improvement a er the procedure.

Platelet-rich plasma
Platelet rich plasma is a therapy using blood with high levels of platelet containing growth factors, esp.for accelera on in healing and regenera on.Recently.platelet-rich plasma has been used in trea ng dark circles due to tear trough deformity and wrinkles.A single session with intradermal injec ons of 1.5ml platelet-rich plasma was given into the tear trough area and wrinkles of crow's feet.The eff ect was compared to three months a er treatment with baseline.The improvement in infraorbital color homogeneity was sta s cally signifi cant. 37

Micro-focused ultrasound
Micro-focused (or intense focused) ultrasound corrects mild to moderate skin and so ssue laxity by short dura on (25 to 50 ms) pulses of transcutaneous ultrasound energy with frequencies in the megahertz (MHz) range to create precise areas of spa ally focused, chromophore-independent thermal coagula ve damage, sparing intervening ssues or overlying skin. 38A single treatment session of intense focused ultrasound for infraorbital laxity treatment has shown increase re cular dermal collagen and thickness. 39

Surgery
Blepharoplasty helps in elimina ng dark circles caused by shadows that are cast by fat deposits or excess skin.Transconjunc val blepharoplasty is a be er approach than transcutaneous blepharoplasty so that no external visible scar is created.Targe ng the contribu ng causes for infraorbital dark circles, the combina on of transconjunc val blepharoplasty and deep-depth phenol chemical peel for pseudohernia on of the orbital fat and treatment of hyperpigmenta on of the skin have found be er outcome. 40

Others
Carboxytherapy: Carboxytherapy employs injec ons to infuse gaseous carbon dioxide below the skin into subcutaneous ssue through a needle and Paolo et al 41 found a signifi cant improvement in fi ne lines and POH a er the use of subcutaneous injec ons of carbon dioxide once a week for seven weeks in the periorbital area.
Normobaric oxygen therapy: Recently oxygen was administered via a nasal cannula at a rate of 1lt/min, for 1 hour twice weekly for 3 weeks.The major clinical changes following treatment included lightening of the color and reduc on in size of darkened area and decrease in pigmenta on and erythema on dermascopy. 42

Conclusion
POH is a common benign facial cosme c problem with mul ple factorial e ology.Though, there are a number of treatment op ons available for periorbital hyperpigmenta on, there is a lack of evidencebased studies for the treatment.It is important to iden fy the pa ern of POH to adapt the treatment modali es in the individual pa ent.Pigmented POH may be eff ec vely treated with bleaching agents (hydroquinone, a triple combina on, kojic acid etc.), chemical peels, pigmented lasers, whereas vascular POH may be treated with topical vitamin K products, vascular lasers and IPL.Structural POH may be treated with Platelet rich plasma, frac onal lasers, fi llers, autologous fat transplanta on, blepharoplasty and mixed POH may be treated with the combina on of the above-men oned modali es to improve the quality of life of the pa ents.