Pigmentation is a localized deepening of skin tone resulting in varying intensity and unevenness of facial tones, which is essentially a localized increase in pigmentation of the facial skin. The ultimate goal of pigmentation treatment is to make the entire facial complexion look consistent. In addition, the same patient often suffers from several different types of pigmentation in combination, and the corresponding combination of treatment should be carried out according to the different symptoms. Therefore, the key to pigmentation treatment is correct diagnosis with proper treatment.
There are seven kinds of common facial pigmentation in plastic surgery: freckles, coffee milk spots, inflammatory pigmentation, age spots, chloasma, acquired nevus of Ota and nevus of Ota.
I. Freckles
The onset of freckles is an autosomal dominant disorder. Most of the freckles are decided before birth, and their symptoms are tiny yellow-brown spots on the face, which develop at school age, become obvious at puberty, and turn inconspicuous at middle age. It is more common in women and the symptoms intensify during pregnancy, so it may be related to female hormones. The skin of patients is mostly fair and dry. Freckles tend to be scattered on the cheeks, lower eyelids, and the root of the nose, while some patients involve the upper eyelids, forehead, nose, perioral area, or even widely distributed over the whole body. Sunlight can aggravate the symptoms of freckles, so freckles are more obvious in summer, and freckle patients should use sunscreen in summer and on strong sunny days.
The pigmentation of freckles is located in the epidermis, and its pathological manifestation is the increase of melanin in the basal layer of the epidermis, while the number of melanocytes does not increase significantly.
Currently, the more effective treatments for freckles are intense pulsed light (photon) and Q-switched laser. Photon treatment does not break the skin, so there is no need for post-treatment vacation, and because of the large treatment head, the entire face can be treated without missing a beat. Q-switched laser (commonly used 532nm, 755nm, 694nm) is also very effective for freckle treatment, usually only 1-2 treatments are needed to achieve complete elimination, but the disadvantage is that the treatment will damage the epidermis, requiring a few days of rest and recovery time. In addition, for the very small and unidentifiable freckle lesions, the treatment cannot be done one by one. It is worth noting that most of the freckles will recur to varying degrees after treatment, and so far it is difficult to find a cure with long-term effect.
Coffee-milk spot
Coffee-milk spot is a kind of autosomal dominant disorder, which is a kind of congenital coffee-colored spot on the surface of the skin, with different size and shape, clear border and uniform color, just like coffee with milk, the texture of its surface skin is completely normal, and it can appear on the face or various parts of the body. This kind of pigmentation is not affected by ultraviolet radiation as freckles are. A coffee-milk spot that exists alone is only a birthmark and does not have adverse health effects. If more lesions are present at the same time, the presence of “neurofibromas” should be taken into account.
The pathological changes of coffee milk spots are similar to those of freckles, which are also pigmented changes located in the epidermis, with congenital localized pigment cells being active, but the total number of localized pigment cells does not increase.
For the treatment of coffee milk spots, Q-switched laser is preferred. The commonly used wavelengths are 532nm (frequency doubling Nd:YAG), 755nm (emerald) and 694nm (ruby), which are safe and will not produce scarring. However, the recurrence rate of some patients is beyond imagination. For some young children, if the Q-switched laser treatment cannot be implemented due to pain, you can use intense pulsed light multiple treatments, you can also receive certain results.
Third, inflammatory hyperpigmentation
In the case of skin damage such as trauma or burns, there will be varying degrees of hyperpigmentation, especially in the Oriental population, where the degree and duration of this hyperpigmentation is more severe than in Caucasians. In general, some dermal injuries (equivalent to second-degree burns) will heal in about 2 weeks, when the skin will appear pink and then turn dark red or maroon, with the red fading and the brown remaining for weeks to months, the duration of which is related to the extent of the skin injury, the site of the injury, the degree of inflammation during the healing process, and individual differences, and the shape of the hyperpigmentation is often The shape of this hyperpigmentation is often consistent with the shape of the skin injury.
The histological manifestation of PIH is an increase in melanin in the basal layer of the epidermis, which may, in addition, be accompanied by a histological pigmentation disorder in the superficial dermis, where melanin droplets are seen under the dermis as well as phagocytic melanocytes. In addition, there are non-specific inflammatory manifestations such as increased capillarity and cellular infiltration in the superficial dermis, as well as varying degrees of increased collagen fibers and decreased epidermal protrusions in the dermis.
The principle of treatment for PIH is “no treatment”, and in particular, all topical treatment of hyperpigmented areas should be avoided. Theoretically, all PIH will subside naturally, but only for a short or long time. It usually takes six months for PIH to fade on the face, and 1-2 years or more on the trunk and lower extremities. The use of invasive or irritating treatments, such as laser, grinding, peeling, etc., while PIH is not fading is often counterproductive, as these treatments can cause new skin trauma and inflammation to the area, resulting in new hyperpigmentation. If it is necessary to give patients some measures, conservative treatments such as oral vitamin C and avoiding ultraviolet radiation can be taken.
Age spots
Age spots, also known as senile pigmentation spots, seborrheic keratosis or heliotrophic nevus, are the most common facial pigmentation spots, which are acquired brown spots, varying in size from rice grains to several centimeters in diameter, single or multiple, with a tendency of slow expansion and gradual color deepening. Sometimes a small irritation can produce a transient inflammation with an increase in thickness, with elevations or lesions that remain flat. It can appear on the face as well as on the exposed parts of the upper limbs, slightly more on the sides than on the front. Once it occurs, it is difficult to fade away naturally, and may improve after the lesion is shed due to inflammation or trauma. The difference between the two is that the former is merely a pigmentary abnormality, while the latter is a prominent skin lesion, and many age spots evolve into seborrheic keratoses over the years. Seborrheic keratosis is a primary benign epidermal tumor, or “tumorigenic change”. Seborrheic keratosis is essentially a neoplastic change of the epidermis due to various damages. Among these damages, the largest and most important factor is ultraviolet light. Age spots may also appear after trauma or burns, but they account for a smaller percentage, and the main cause is still ultraviolet light.
Pathological manifestations of age spots. Initially, age spots only show simple epidermal hypertrophy and an increase of melanin granules in the basal and upper layers, after which basal cells proliferate and mild hyperkeratosis occurs. This basal cell proliferation starts from the basal layer and grows upward in the form of buds and cords, and after various differentiations, it may become various kinds of acanthocytes, after which various histological changes appear in seborrheic keratosis. The histological manifestations of seborrheic keratosis are classified into hypertrophic type, hyperkeratotic type, reticular type i.e. adenoid type, and irritated type. Their histological manifestations are different, and none of them even looks like the same disease, but their essence is the proliferation of basal cells, with spiny cells, and the cells do not appear to be mutated, and they are epidermal benign neoplastic lesions.
The treatment of age spots varies according to the degree of the lesion. For age spots that are not higher than the skin surface, the best treatment method is Q-switched laser, the commonly used wavelengths are 694nm (ruby), 755nm (emerald), 532nm (multiplier Nd:YAG), the treatment is safe and usually only one time is needed to cure. For those seborrheic keratoses that are above the skin surface, the best treatment is the CO2 laser with definite results. For some lesions with both flat and high skin surface, a combination of the above two treatments is possible.
V. Melasma
Melasma is a kind of acquired facial pigmentation, which is common in women and mostly develops in adulthood, especially after middle age, presenting as diffuse flocculent pigmentation with unclear boundary, sometimes it can be distributed in a network, often appearing in the cheekbone, forehead and around the mouth and lips, usually symmetrically distributed on the left and right, rarely appearing in the parts of hair, the pigmentation will change in intensity with time, and pregnancy and sun exposure will worsen the lesions. Pregnancy and sunlight will worsen the lesions, and the symptoms will gradually decrease after the patient grows old. The treatment of melasma is very difficult and there is no specific cure so far. Melasma needs to be diagnosed differently from acquired nevus of Ota (ADM), which is sometimes difficult to distinguish, and some patients suffer from both diseases, requiring careful differentiation and gradual treatment.
The histological manifestation of melasma is mainly an increase in melanin granules in the basal layer of the epidermis and its superficial layers. Of course, its degree is proportional to the degree of melasma lesion. Sometimes it is manifested as an increase in the number of pigment cells, but also as an increase in the size of individual pigment cells. It is not very clear whether the lesions of melasma are related to such melanocyte changes. The dermal changes are the degeneration of elastic fibers and the appearance of phagocytic melanocytes. The former is a normal change in the exposed parts of the skin of middle-aged and elderly people, and the latter is the result of inflammatory pigmentation and is not a histological change specific to melasma. Some melasma also has increased melanin in the dermis, so it is thought that it can also be divided into epidermal melasma and dermal melasma.
The etiology of melasma is still unclear and there are many speculations, including the endocrine theory that it is related to estrogen, but this theory is difficult to explain the appearance of melasma on the faces of some patients who have had their ovaries removed and male patients. There is also the stress theory, but this theory has difficulty explaining why the discoloration appears only in certain specific areas. A more novel explanation is that the pigmentation occurs due to chronic irritation of certain areas, resulting in a decrease in the skin barrier action in that area, similar to some specific inflammatory hyperpigmentation. Supporting this explanation is the fact that about 3/4 of patients have the habit of rubbing and washing the face vigorously at the time of history taking, and the symptoms of melasma improve after stopping the irritation of the skin; the use of some invasive treatments is often ineffective and aggravates the symptoms of melasma.
So far, there is no special treatment for melasma. If we use some invasive methods (such as laser, etc.) to treat melasma rashly, it will often produce the opposite effect and sometimes cause medical disputes. There are some treatments that are controlled at the epidermis layer that may temporarily relieve melasma at the epidermis layer, but have no effect on the deeper melasma layer, which will soon recur.
Currently, among all melasma treatments, oral tranexamic acid is the most effective conservative treatment. Tranexamic acid can be taken at low doses (250mg, Bid) for a long time (6-30 months), and the effect usually appears in 1-2 months with an efficiency of 80%. This method has been used in Japan for nearly 20 years, with very good results and minimal side effects, and has become the preferred treatment for melasma in Japan. Its therapeutic mechanism is not yet clear. It is generally believed that cytokinin has an activating effect on the proliferation of pigment cells or a certain link of melanin formation, while tranexamic acid may have an inhibiting effect on cytokinin, or it may have a direct therapeutic effect. In addition, it has also been suggested that tranexamic acid may be able to block a certain link in melanin formation. It is worth noting that while taking the drug orally, the patient must be instructed to stop all cosmetic operations that stimulate the skin and avoid continuing to over-stimulate the skin of the face, especially the melasma area, which some even consider more important than taking the drug itself.
VI. Acquired nevus of Ota
Acquired nevus of Ota has many aliases, such as acquired dermal melanocytosis , delayed bilateral maternal Ota-like pigmentation, delayed bilateral maternal Ota-like pigmentation, Hori’s mother spot and so on.
In 1984, Hori et al. reported a gray-brown discoloration appearing symmetrically on both sides of the cheek, temporal, nasal root, nasal flank, eyelid, and forehead, with histological changes of diffuse melanosis in the superficial dermis. This lesion is known as delayed bilateral Ota-like pigmentation. In the early stages, it was thought to be a subtype of nevus of Ota, but since then it has been found to have many symptoms different from those of nevus of Ota: many patients develop it after the age of 20, it has a typical distribution and morphology of pigmentation, it does not involve the palate or the eyes, and in addition, there are familial cases, so it is considered to be a separate disease from nevus of Ota. This disease is basically concentrated in Southeast Asian countries and regions such as Japan, Korea, Taiwan, Thailand, and Singapore, so it is considered to be a disease specific to the population in Asian regions, like nevus of Ota.
There are no official diagnostic criteria for ADM, but the following clinical manifestations can be referred to: discoloration of the face starting at the age of 13 years or older (mostly 20 years or older), with multiple lesions in six specific areas (zygomatic region, lower eyelid, nasal root, nasal flank, temporal region – lateral upper lid, lateral forehead), usually involving more than two areas at the same time, with most patients being symmetrical on both sides Most patients have bilateral symmetry; pathologic examination reveals increased melanin in the dermis; lesions rarely change over time.
Differential diagnosis between ADM and nevus of Ota: most nevus of Ota is under 15 years of age at the onset, whereas ADM is over 15 years of age (more common over 20 years of age); lesions located on the lower eyelid, nevus of Ota sometimes progresses to the medial aspect of the nose or even involves the upper eyelid, but ADM does not; lesions located on the upper eyelid, nevus of Ota is mostly located in the center or medial aspect of the upper lid and almost always presents as a diffuse lesion, whereas ADM For lesions on the root of the nose, nevus of Ota appears as a gradual fading with unclear borders, while ADM appears as a “bow-tie” with clear upper and lower borders and fading out from side to side. Nevus of Ota sometimes involves the palate and conjunctiva, while ADM is rare; Nevus of Ota rarely occurs in families, while ADM has a tendency to occur in families.
Differential diagnosis of ADM and melasma: for lesions located on the forehead, ADM is mostly located on both sides of the forehead, while melasma is mostly located in the center of the forehead or above the eyebrows. In addition, if located on both sides of the forehead where hair grows, ADM will grow across the area with hair, while melasma will not involve the area with hair growth; for lesions located on the outer part of the upper eyelid, ADM appears in the form of small blotches. Melasma is a diffuse lesion that exhibits a nail size that follows the same course as the eye sockets; lesions located in the zygomatic region, ADM mostly presents as small spots, and occasionally severe ADM is a diffuse lesion in which small spots are continuous into large patches. Melasma is a diffuse lesion; melasma does not usually appear on the nasal area; in terms of color, melasma is usually a slightly reddish yellow-brown color, while ADM is gray and mostly inconspicuous; melasma changes in various ways over time, while ADM generally has little change in terms of intensity. It is important to note that ADM and melasma often occur in combination.
The histologic change in ADM is melanin proliferation in the superficial dermis. Melanin in the dermis manifests as spindle-shaped cells with brown melanin granules that are encapsulated within the dermal collagen. The histologic changes in ADM often show hyperpigmentation in the basal layers of the epidermis, but this change is not specific to ADM and is likely to be a histologic change in melasma, which is often combined with ADM. The epidermis is largely uninvolved. However, histologic changes in ADM often reveal an increase in intracellular melanin granules in the basal layer of the epidermis and its superficial layers. Nevus of Ota, which is an intra-dermal melanoproliferative disease like ADM, also shows similar intra-epidermal changes, but they do not occur to the same extent as in ADM.
The treatment of ADM, like nevus of Ota, can completely remove its intra-dermal melanin using Q-switched lasers (694nm, 1064nm, 755nm). Depending on the depth of the lesion and the type of machine, 3-5 treatments are usually required, with an interval of 3-6 months between treatments.
VII. Comprehensive comments
1.The relationship between UV and pigmentation
UV is not the direct cause of discoloration in many cases. Although the deepening of pigmentation can be caused within just a few days after UV radiation, this deepening of pigmentation is comprehensive, not only deepening the area with pigmentation. In addition, after the aggravation of pigmentation caused by UV radiation, the whole facial skin tone including pigmentation will return to the state before the radiation when the sunlight condition improves. It is widely believed that the onset of age spots is related to UV exposure, but this relationship is based on the results of photoaging effects resulting from the accumulation of several years or even decades of exposure.
It is important to defend against UV rays in order to prevent the exacerbation of the symptoms of discoloration, as well as to prevent the long-term photoaging effect. The use of sunscreen is a common means, sunscreen has two key indicators SPF and PA. SPF is called sun protection index, which refers to the ability of sunscreen to fight against UVB, for example, if the skin reddens 10 minutes after the original exposure, it takes 200 minutes after applying sunscreen for the skin to redden, which is 20 times longer, then the sun protection index of this sunscreen is 20. PA is sun protection ability, which refers to Sunscreen against ultraviolet A ability, there are +, + + +, + + + three, the higher the level, the stronger the ability to resist tanning. It is important to note that the higher the index the better when buying sunscreen, because the higher the SPF, the more sunscreen agents (such as titanium dioxide and zinc oxide) it contains, which can irritate the skin and cause clogged pores. Therefore, you should choose the appropriate sunscreen according to the environment. People who work indoors only need to use the one with an index of 20 or less, while those who run around outdoors can choose the one with an index of 20-30.
2.The relationship between psychological stress and pigmentation
Some people think that mental stress will cause the aggravation of pigmentation, but there is no reliable basis for this statement. “Mental stress” has an effect on the higher nervous system, but it is hard to imagine that mental stress will directly cause skin discoloration. A more reasonable explanation is that when individuals are under excessive mental stress, they will have a serious face, poor sleep, no time to take care of their facial skin, or even endocrine disorders, which cause the dullness of facial skin tone and the deepening of the original pigmentation.
3.The relationship between age and pigmentation
Except for the congenital pigmentation, most of the pigmentation spots appear at a certain age and worsen with age. The congenital coffee milk spots, freckles and nevus of Ota appear at an earlier age, while melasma, acquired nevus of Ota and age spots appear at a later age, and they often become obvious and affect the appearance only after years of gradual accumulation. Therefore, differential diagnosis can be made when taking medical history. It should be noted that many patients’ complaints are not very reliable because they often do not notice them in the early stage of pigmentation, so when patients complain about the sudden appearance of pigmentation recently, or even overnight, we should analyze them specifically.
4.The relationship between skin texture and pigmentation
Skin quality refers to the nature of the skin, and compared with other diseases, the relationship between skin quality and pigmentation is closer. Some skin types are more prone to pigmentation, but the skin type prone to pigmentation does not mean that all pigmentation is easy to grow, but only that a specific pigmentation is easy to appear. Take freckles as an example, most freckle patients have fair and dry skin, and these people are not prone to freckle-like moles. Although age spots are also easy to grow on fair and dry skin, they seem to be more common in people with thinning hair. On the contrary, melasma tends to be seen in people with fair skin and thick hair who also tend to develop freckle-like nevi. The skin of people with nevus of Ota tends to be oily and darker in color.
5.Dark circles under the eyes
Dark circles under the eyes are darker than normal, giving people a feeling of not having a good rest or being “old”. From a medical perspective, there are several causes of dark circles under the eyes.
(1) Pigmentation or discoloration of the skin of the lower lid. Because the skin around the eyes is very thin and often exposed to various cosmetics, it is prone to inflammation, which over time leads to the formation of hyperpigmentation or discoloration.
(2) Subcutaneous thickened veins or venous stasis. Strain can lead to poor blood flow, dark venous blood stagnation in the orbicularis oculi muscle, through the skin on the formation of dark circles, those with fair and thin skin are more likely to appear this phenomenon;.
(3) the shadow of the bags under the eyes. Especially those more serious bags under the eyes, in the role of light will form a shadow below it.
(4) Fine wrinkles on the lower eyelids. Middle-aged women tend to have many tiny wrinkles in that area, and in the light, the wrinkled area will absorb more light than the smooth area, giving a darker look.