Cheuk Hung Lee, MBBS (HK), FHKAM (MED), FHKCP, MScPD (Cardiff), MRCP (UK), DPD (Wales), DipDerm (Glasgow), PGDipClinDerm (London), MRCP (London), GradDipDerm (NUS), DipMed (CUHK)1 , Kar Wai Alvin Lee, MBChB (CUHK), DCH (Sydney), Dip Derm (Glasgow), MScClinDerm (Cardiff), MScPD (Cardiff), DipMed (CUHK), DCH (Sydney)1 , Lisa Kwin Wah Chan, MBChB (CUHK), MScPD (Cardiff), PgDipPD (Cardiff), PGDipClinDerm (Lond), DipMed (CUHK), DCH (Sydney)1 , Kar Fai Victor Lee, MBBS (UCL, University of London), MRCP (UK), FRCP (Glasgow), FHKCP, FHKAM (Medicine)2
1Ever Keen Medical Centre, Hong Kong
2London Heart Practice, Hong Kong
Correspondence to :
Lisa Kwin Wah Chan
E-mail: lisa827@gmail.com
© Korean Society of Korean Cosmetic Surgery & Medicine
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Photoaging is a process in which ultraviolet radiation damages the normal skin architecture. Topical chemical peeling is used to treat this condition. The authors aimed to understand the mechanism and level of evidence of the different depths of chemical peeling used to treat photoaging. Various topical chemical peelings have been used in cosmetic medicine for many years to treat photodamaged skin. This review compares the efficacy and the level of evidence. This systematic review evaluates the efficacy of different chemical peeling methods. Keywords included “Photoaging,” “Alpha-hydroxy acid,” “Lipo-hydroxy acid,” “Trichloroacetic acid,” “Jessner’s solution,” and “Phenol” were typed on Ovid, PubMed, MEDLINE for relevant studies published on photoaging treatment. There is a wealth of Level I evidence supporting the use of topical retinoic acid, vitamin B, and vitamin C. The evidence behind the use of topical vitamin E exists but is mainly drawn from studies from the Level IV of the evidence hierarchy. Topical vitamins can effectively treat photodamaged skin.
Keywords: hydroxy acids, lactic acid, phenol, salicylic acid, skin aging, trichloroacetic acid
The principle of the ablative resurfacing technique is the process of regenerating tighter and even healthier skin. It is characterized by a predefined skin layer-controlled elimination. Skin regeneration is stimulated by caustic chemicals that destroy the skin layers prior to skin regeneration [1]. Since the time of Cleopatra, her anti-aging purposes were accomplished by pouling sour milk on her face. Even the ancient Greeks and Romans used the same technique during their time. In 1874, the first recorded chemical peeling treatment was performed by Von Hebra, who treated freckles, Addison’s disease, and melasma with chemical peels [2]. Eller and Wolff [3] treated scars with carbon dioxide, salicylic acid, resorcinol, and phenol, whereas Kligman et al. [4] treated post-acne scars with phenol.
Newer chemical peels, such as lipohydroxy acid, Jessners solution, alpha-hydroxy acids (AHA), and trichloroacetic acid (TCA), were later developed. Jessner’s solution contains ethyl alcohol, resorcinol, salicylic acid, and lactic acid, whereas AHA include tartaric, citric, malic, lactic, and glycolic acids, which are foods of origin. The usual course of treatment was six treatments every half or a whole month, with no significant downtime. Skin rejuvenation effects include acceleration of desquamation and epidermal remodeling.
The following keywords were searched in the Ovid, PubMed, and MEDLINE databases for relevant studies published on photoaging treatment: photoaging, superficial peel, medium peel, deep peel, alpha-hydroxy acid, lipo-hydroxy acid, TCA, Jessner’s solution, and phenol. Some studies were further reviewed based on objective endpoint measurements, a double-blind approach, control usage, randomization usage, and sample size. All studies were classified according to the Oxford Center for Evidence-Based Medicine Evidence Hierarchy (Fig. 1) [5].
Ditre et al. [6] conducted a histological double-blind placebo-controlled study on patients’ forearms, with one arm having a control lotion and another arm having AHA peel (citric, lactic, or 25% glycolic acids). After six months, skin biopsies were taken from both arms, which demonstrated an increased density of collagen, better elastic fiber quality, raised acid mucopolysaccharides in the papillary dermis and epidermis, and increased skin thickness by 25% on the AHA peel side compared to the control arm (Level IIb evidence). With a double-blind design and vehicle control, this is a high-quality study, and with an objective histological endpoint, this study is of good strength [6].
Butler et al. [7] used photoaged mouse skin treated with chemical peels for histological analysis. One hundred hairless mice were exposed to ultraviolet B light to photoage their skin for fourteen weeks. Five comparable groups were formed: phenol peel vs. control, 50% TCA vs. control, 30% TCA vs. control, 50% glycolic acid vs. control, and control vs. control. Except for the last comparable group (control vs. control), at 28 days, an increase in collagen content was observed in all of the chemical peel groups (p<0.05). Furthermore, at 60 days, collagen reorganization was observed in the papillary and reticular dermis in all the chemical peel groups, although the collagen content returned to normal. In addition, there was an increased dermal layer thickness in the phenol and 50% TCA groups compared to that of in the control group (Level IV Evidence).
Yamamoto et al. [8] performed a histological study on skin treated with AHA, including acetic acid, citric acid, lactic acid, and glycolic acid, once daily for 42 days. With the exception of acetic acid, all other acids increased the levels of procollagen I and collagen I (level IV) in the upper dermis.
Newman et al. [9] provided the best-quality evidence for the benefits of chemical peels on photoaged skin. They enrolled 41 subjects in their double-blind split-face study, with vehicle lotion on one side of the face and 50% glycolic acid on the other side for four weeks. Objective histological assessment of the skin biopsy and subjective assessment of photoaging were performed as endpoints. The objective histological assessment revealed an increase in epidermal thickening and collagen content, improvement in stratum corneum thinning, and granular layer enhancement on the side of the 50% glycolic acid peel. Subjective assessment also showed that solar lentigine lightening, less solar keratosis, fine wrinkle reduction, and less rough skin texture were noted on the side treated with 50% glycolic acid peel compared to the side treated with vehicle lotion only (Level IIb Evidence).
Kligman and Kligman [10] conducted a research with a number of case series about chemical peeling on patients with photoaged skin. The authors found that salicylic acid with AHA peels caused fine rhytide reduction, reduced roughness of the skin surface, and fading of pigmented spots when treated at four weekly intervals (Level IV Evidence). Nevertheless, the endpoint assessment in this study was non-objective and this was a non-blinded study with a small a number of patients.
Reed et al. [11] conducted a single-blind study of 24 patients with facial perioral wrinkles. This was a split-face study, with carbon dioxide laser treatment on one side of the face and medium-depth TCA on the other side. Both treated sides showed improvement, with a higher wrinkle score reduction on the side treated with laser, although post-treatment erythema lasted shorter on the peel-treated side. The wrinkle score reduced from 4.13 to 3.29 (Level IV Evidence).
Contrary to the results of the previous study, Chew et al. [12] performed a single-blind study of 20 subjects with facial perioral wrinkles. This was also a split-face study in which every subject was treated with a carbon dioxide laser on one side of the face and Baker’s phenol (deep chemical peel) on the other side. Before treatment and at six-month intervals, a blinded investigator was asked to rate the rhytides on a five-point scale. Both sides experienced wrinkle score reduction, with peel treated side experienced more dramatic wrinkle score reduction from 4.3 to 0.47 at six months interval (Level IV Evidence).
Chemical peels are classified as deep (limited to the reticular dermis), medium (limited to the papillary dermis), and superficial (limited to the epidermal layer). The deep peel ablates the reticular layer of the dermis and destroys the superficial dermis and epidermis. A study on phenol peeling showed that during deep peeling, novel collagen bands and fibers parallel to the skin surface appeared in the dermal layer, the basal cell melanin grains were homogenized, the melanocytes were distributed uniformly, and the architecture of the epidermis normalized [13].
Deep peels such as phenol and medium peels such as TCA can restore the architecture of the dermal layer by triggering regeneration, destroying the dermal layer, and stimulating membrane protein coagulation. Furthermore, phenol stops the transfer of melanocytes from melanosomes to the nearby keratinocyte [14].
Research has shown that superficial peels such as LHA and glycolic acid can disrupt the stratum corneum desmosome, stimulating the stratum corneum to break down [15,16], creating a new epidermal layer through epidermal cell multiplication and regeneration, resulting in skin desquamation. Furthermore, AHA has been shown to stimulate the production of epidermal cytokines, inducing elastin production, and collagen types I and IV. It can also induce exfoliation and epidermolysis, and increase enzyme activity in the epidermal layer [17].
Skin priming is an important step before chemical peeling. This process uses cosmeceutical or pharmaceutical agents prior to peeling procedure [18]. Sunscreens, hydroquinone, AHA, and tretinoin are typical skin-priming agents. Patients with a history of herpes skin infection were better prepared with oral acyclovir before the chemical peeling procedure, which was continued for seven days after treatment.
Furthermore, chemical peeling for photoaging is not without risks and side effects. Patients may experience skin infection, especially if the skin is not properly cleaned and cared for after the treatment. Scarring can also be seen in rare cases, particularly if the chemical solution is too strong or if the skin is not properly cared for after the treatment. Moreover, Pigment changes can be seen in patients with darker skin tones, which clinically the treated area may become darker or lighter than the surrounding skin. Skin sensitivitiy can be seen in some patients who complain of becoming more sensitive to sunlight after the treatment. Thus, it is recommended to wear sunscreen and avoid direct exposure to the sun after chemical peeling. Skin irritation is commonly seen as well, which is a normal response to the chemical solution. Clinically, some patients experience erythema, swelling, and pruritus in treatment area. The potential benefits of chemical peels must be balanced against the risks and side effects [19].
There are alternative treatments for photoaging besides chemical peels: Retinoids, which are topical creams or gels that contain vitamin A derivatives, which help reduce the appearance of fine lines, wrinkles, and other signs of aging [20]; Microneedling, which uses a small, handheld device to create tiny punctures in the skin, stimulate collagen production, and promote skin rejuvenation [21]; Light therapy, also known as phototherapy, which uses different wavelengths of light to target specific skin concerns, such as fine lines and wrinkles [22]; Laser resurfacing: which uses a laser to remove damaged skin cells and stimulate the growth of new skin cells [23]; last but not least, microdermabrasion, which is a non-invasive procedure that uses a special device to exfoliate the top layer of skin, revealing fresher, younger-looking skin [24]. It is important to note that the effectiveness of these treatments may vary depending on the severity of the photoaging and individual skin type. It is always best to consult with a dermatologist or skincare professional to determine the best treatment plan to fulfill the patient need.
Furthermore, there are a few limitations which should be addressed in future studies in chemical peeling treating photoaged skin:
1. Absence of established protocols: Chemical peeling for the treatment of photoaged skin still lacks a standardized protocol. Because of this, it is challenging to evaluate the findings of many studies and choose the best method and treatment parameters.
2. Small sample sizes: The findings from many studies in this field cannot be generalized due to their small sample size.
3. Short follow-up times: Because some trials had relatively short follow-up times, it is difficult to determine if chemical peels are safe and effective in treating photoaged skin over the long term.
4. Absence of objective metrics: Several studies rely on subjective evaluations of the success of the treatment, such as patient reported outcomes or physician ratings. Data from objective measurements, such skin biopsies or imaging tests, would be more trustworthy.
5. Restricted diversity: Because most studies have been done on Caucasian populations, we know very little about how chemical peeling might affect people of diverse racial and ethnic backgrounds.
6. Lack of comparison to other treatments: Chemical peeling has not been extensively studied in contrast to other treatments for photoaging, such as dermabrasion or laser resurfacing. The relative efficacy and safety of these various techniques could be ascertained with the aid of comparative research.
In conclusion, there are a number of studies with level IV evidence supporting the use of chemical peeling in photoaging treatment. The included studies have limitations, such as small sample sizes and some without any objective endpoint measurements. Nevetheless, there is one good double-blind split-face controlled study (by Newman et al [9], using 50% glycolic acid) with level IIb evidence supporting the use of chemical peeling in photoaged patients. More high-quality studies with larger sample sizes and extended follow-up periods are required to determine the best approach for treating photoaging.
The authors have nothing to disclose.
J Cosmet Med 2023; 7(1): 1-5
Published online June 30, 2023 https://doi.org/10.25056/JCM.2023.7.1.1
Copyright © Korean Society of Korean Cosmetic Surgery & Medicine.
Cheuk Hung Lee, MBBS (HK), FHKAM (MED), FHKCP, MScPD (Cardiff), MRCP (UK), DPD (Wales), DipDerm (Glasgow), PGDipClinDerm (London), MRCP (London), GradDipDerm (NUS), DipMed (CUHK)1 , Kar Wai Alvin Lee, MBChB (CUHK), DCH (Sydney), Dip Derm (Glasgow), MScClinDerm (Cardiff), MScPD (Cardiff), DipMed (CUHK), DCH (Sydney)1 , Lisa Kwin Wah Chan, MBChB (CUHK), MScPD (Cardiff), PgDipPD (Cardiff), PGDipClinDerm (Lond), DipMed (CUHK), DCH (Sydney)1 , Kar Fai Victor Lee, MBBS (UCL, University of London), MRCP (UK), FRCP (Glasgow), FHKCP, FHKAM (Medicine)2
1Ever Keen Medical Centre, Hong Kong
2London Heart Practice, Hong Kong
Correspondence to:Lisa Kwin Wah Chan
E-mail: lisa827@gmail.com
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Photoaging is a process in which ultraviolet radiation damages the normal skin architecture. Topical chemical peeling is used to treat this condition. The authors aimed to understand the mechanism and level of evidence of the different depths of chemical peeling used to treat photoaging. Various topical chemical peelings have been used in cosmetic medicine for many years to treat photodamaged skin. This review compares the efficacy and the level of evidence. This systematic review evaluates the efficacy of different chemical peeling methods. Keywords included “Photoaging,” “Alpha-hydroxy acid,” “Lipo-hydroxy acid,” “Trichloroacetic acid,” “Jessner’s solution,” and “Phenol” were typed on Ovid, PubMed, MEDLINE for relevant studies published on photoaging treatment. There is a wealth of Level I evidence supporting the use of topical retinoic acid, vitamin B, and vitamin C. The evidence behind the use of topical vitamin E exists but is mainly drawn from studies from the Level IV of the evidence hierarchy. Topical vitamins can effectively treat photodamaged skin.
Keywords: hydroxy acids, lactic acid, phenol, salicylic acid, skin aging, trichloroacetic acid
The principle of the ablative resurfacing technique is the process of regenerating tighter and even healthier skin. It is characterized by a predefined skin layer-controlled elimination. Skin regeneration is stimulated by caustic chemicals that destroy the skin layers prior to skin regeneration [1]. Since the time of Cleopatra, her anti-aging purposes were accomplished by pouling sour milk on her face. Even the ancient Greeks and Romans used the same technique during their time. In 1874, the first recorded chemical peeling treatment was performed by Von Hebra, who treated freckles, Addison’s disease, and melasma with chemical peels [2]. Eller and Wolff [3] treated scars with carbon dioxide, salicylic acid, resorcinol, and phenol, whereas Kligman et al. [4] treated post-acne scars with phenol.
Newer chemical peels, such as lipohydroxy acid, Jessners solution, alpha-hydroxy acids (AHA), and trichloroacetic acid (TCA), were later developed. Jessner’s solution contains ethyl alcohol, resorcinol, salicylic acid, and lactic acid, whereas AHA include tartaric, citric, malic, lactic, and glycolic acids, which are foods of origin. The usual course of treatment was six treatments every half or a whole month, with no significant downtime. Skin rejuvenation effects include acceleration of desquamation and epidermal remodeling.
The following keywords were searched in the Ovid, PubMed, and MEDLINE databases for relevant studies published on photoaging treatment: photoaging, superficial peel, medium peel, deep peel, alpha-hydroxy acid, lipo-hydroxy acid, TCA, Jessner’s solution, and phenol. Some studies were further reviewed based on objective endpoint measurements, a double-blind approach, control usage, randomization usage, and sample size. All studies were classified according to the Oxford Center for Evidence-Based Medicine Evidence Hierarchy (Fig. 1) [5].
Ditre et al. [6] conducted a histological double-blind placebo-controlled study on patients’ forearms, with one arm having a control lotion and another arm having AHA peel (citric, lactic, or 25% glycolic acids). After six months, skin biopsies were taken from both arms, which demonstrated an increased density of collagen, better elastic fiber quality, raised acid mucopolysaccharides in the papillary dermis and epidermis, and increased skin thickness by 25% on the AHA peel side compared to the control arm (Level IIb evidence). With a double-blind design and vehicle control, this is a high-quality study, and with an objective histological endpoint, this study is of good strength [6].
Butler et al. [7] used photoaged mouse skin treated with chemical peels for histological analysis. One hundred hairless mice were exposed to ultraviolet B light to photoage their skin for fourteen weeks. Five comparable groups were formed: phenol peel vs. control, 50% TCA vs. control, 30% TCA vs. control, 50% glycolic acid vs. control, and control vs. control. Except for the last comparable group (control vs. control), at 28 days, an increase in collagen content was observed in all of the chemical peel groups (p<0.05). Furthermore, at 60 days, collagen reorganization was observed in the papillary and reticular dermis in all the chemical peel groups, although the collagen content returned to normal. In addition, there was an increased dermal layer thickness in the phenol and 50% TCA groups compared to that of in the control group (Level IV Evidence).
Yamamoto et al. [8] performed a histological study on skin treated with AHA, including acetic acid, citric acid, lactic acid, and glycolic acid, once daily for 42 days. With the exception of acetic acid, all other acids increased the levels of procollagen I and collagen I (level IV) in the upper dermis.
Newman et al. [9] provided the best-quality evidence for the benefits of chemical peels on photoaged skin. They enrolled 41 subjects in their double-blind split-face study, with vehicle lotion on one side of the face and 50% glycolic acid on the other side for four weeks. Objective histological assessment of the skin biopsy and subjective assessment of photoaging were performed as endpoints. The objective histological assessment revealed an increase in epidermal thickening and collagen content, improvement in stratum corneum thinning, and granular layer enhancement on the side of the 50% glycolic acid peel. Subjective assessment also showed that solar lentigine lightening, less solar keratosis, fine wrinkle reduction, and less rough skin texture were noted on the side treated with 50% glycolic acid peel compared to the side treated with vehicle lotion only (Level IIb Evidence).
Kligman and Kligman [10] conducted a research with a number of case series about chemical peeling on patients with photoaged skin. The authors found that salicylic acid with AHA peels caused fine rhytide reduction, reduced roughness of the skin surface, and fading of pigmented spots when treated at four weekly intervals (Level IV Evidence). Nevertheless, the endpoint assessment in this study was non-objective and this was a non-blinded study with a small a number of patients.
Reed et al. [11] conducted a single-blind study of 24 patients with facial perioral wrinkles. This was a split-face study, with carbon dioxide laser treatment on one side of the face and medium-depth TCA on the other side. Both treated sides showed improvement, with a higher wrinkle score reduction on the side treated with laser, although post-treatment erythema lasted shorter on the peel-treated side. The wrinkle score reduced from 4.13 to 3.29 (Level IV Evidence).
Contrary to the results of the previous study, Chew et al. [12] performed a single-blind study of 20 subjects with facial perioral wrinkles. This was also a split-face study in which every subject was treated with a carbon dioxide laser on one side of the face and Baker’s phenol (deep chemical peel) on the other side. Before treatment and at six-month intervals, a blinded investigator was asked to rate the rhytides on a five-point scale. Both sides experienced wrinkle score reduction, with peel treated side experienced more dramatic wrinkle score reduction from 4.3 to 0.47 at six months interval (Level IV Evidence).
Chemical peels are classified as deep (limited to the reticular dermis), medium (limited to the papillary dermis), and superficial (limited to the epidermal layer). The deep peel ablates the reticular layer of the dermis and destroys the superficial dermis and epidermis. A study on phenol peeling showed that during deep peeling, novel collagen bands and fibers parallel to the skin surface appeared in the dermal layer, the basal cell melanin grains were homogenized, the melanocytes were distributed uniformly, and the architecture of the epidermis normalized [13].
Deep peels such as phenol and medium peels such as TCA can restore the architecture of the dermal layer by triggering regeneration, destroying the dermal layer, and stimulating membrane protein coagulation. Furthermore, phenol stops the transfer of melanocytes from melanosomes to the nearby keratinocyte [14].
Research has shown that superficial peels such as LHA and glycolic acid can disrupt the stratum corneum desmosome, stimulating the stratum corneum to break down [15,16], creating a new epidermal layer through epidermal cell multiplication and regeneration, resulting in skin desquamation. Furthermore, AHA has been shown to stimulate the production of epidermal cytokines, inducing elastin production, and collagen types I and IV. It can also induce exfoliation and epidermolysis, and increase enzyme activity in the epidermal layer [17].
Skin priming is an important step before chemical peeling. This process uses cosmeceutical or pharmaceutical agents prior to peeling procedure [18]. Sunscreens, hydroquinone, AHA, and tretinoin are typical skin-priming agents. Patients with a history of herpes skin infection were better prepared with oral acyclovir before the chemical peeling procedure, which was continued for seven days after treatment.
Furthermore, chemical peeling for photoaging is not without risks and side effects. Patients may experience skin infection, especially if the skin is not properly cleaned and cared for after the treatment. Scarring can also be seen in rare cases, particularly if the chemical solution is too strong or if the skin is not properly cared for after the treatment. Moreover, Pigment changes can be seen in patients with darker skin tones, which clinically the treated area may become darker or lighter than the surrounding skin. Skin sensitivitiy can be seen in some patients who complain of becoming more sensitive to sunlight after the treatment. Thus, it is recommended to wear sunscreen and avoid direct exposure to the sun after chemical peeling. Skin irritation is commonly seen as well, which is a normal response to the chemical solution. Clinically, some patients experience erythema, swelling, and pruritus in treatment area. The potential benefits of chemical peels must be balanced against the risks and side effects [19].
There are alternative treatments for photoaging besides chemical peels: Retinoids, which are topical creams or gels that contain vitamin A derivatives, which help reduce the appearance of fine lines, wrinkles, and other signs of aging [20]; Microneedling, which uses a small, handheld device to create tiny punctures in the skin, stimulate collagen production, and promote skin rejuvenation [21]; Light therapy, also known as phototherapy, which uses different wavelengths of light to target specific skin concerns, such as fine lines and wrinkles [22]; Laser resurfacing: which uses a laser to remove damaged skin cells and stimulate the growth of new skin cells [23]; last but not least, microdermabrasion, which is a non-invasive procedure that uses a special device to exfoliate the top layer of skin, revealing fresher, younger-looking skin [24]. It is important to note that the effectiveness of these treatments may vary depending on the severity of the photoaging and individual skin type. It is always best to consult with a dermatologist or skincare professional to determine the best treatment plan to fulfill the patient need.
Furthermore, there are a few limitations which should be addressed in future studies in chemical peeling treating photoaged skin:
1. Absence of established protocols: Chemical peeling for the treatment of photoaged skin still lacks a standardized protocol. Because of this, it is challenging to evaluate the findings of many studies and choose the best method and treatment parameters.
2. Small sample sizes: The findings from many studies in this field cannot be generalized due to their small sample size.
3. Short follow-up times: Because some trials had relatively short follow-up times, it is difficult to determine if chemical peels are safe and effective in treating photoaged skin over the long term.
4. Absence of objective metrics: Several studies rely on subjective evaluations of the success of the treatment, such as patient reported outcomes or physician ratings. Data from objective measurements, such skin biopsies or imaging tests, would be more trustworthy.
5. Restricted diversity: Because most studies have been done on Caucasian populations, we know very little about how chemical peeling might affect people of diverse racial and ethnic backgrounds.
6. Lack of comparison to other treatments: Chemical peeling has not been extensively studied in contrast to other treatments for photoaging, such as dermabrasion or laser resurfacing. The relative efficacy and safety of these various techniques could be ascertained with the aid of comparative research.
In conclusion, there are a number of studies with level IV evidence supporting the use of chemical peeling in photoaging treatment. The included studies have limitations, such as small sample sizes and some without any objective endpoint measurements. Nevetheless, there is one good double-blind split-face controlled study (by Newman et al [9], using 50% glycolic acid) with level IIb evidence supporting the use of chemical peeling in photoaged patients. More high-quality studies with larger sample sizes and extended follow-up periods are required to determine the best approach for treating photoaging.
The authors have nothing to disclose.
Arthur Yu, MBBS (HK), Cheuk Hung Lee, MBBS (HK), FHKAM (MED), FHKCP, MScPD (Cardiff), MRCP (UK), DPD (Wales), DipDerm (Glasgow), PGDipClinDerm (London), MRCP (London), GradDipDerm (NUS), DipMed (CUHK), Kar Wai Alvin Lee, MBChB (CUHK), DCH (Sydney), Dip Derm (Glasgow), MScClinDerm (Cardiff), MScPD (Cardiff), DipMed (CUHK), DCH (Sydney), Lisa Kwin Wah Chan, MBChB (CUHK), MScPD (Cardiff), PgDipPD (Cardiff), PGDipClinDerm (Lond), DipMed (CUHK), DCH (Sydney)
J Cosmet Med 2023; 7(2): 88-93 https://doi.org/10.25056/JCM.2023.7.2.88Cheuk Hung Lee, MBBS (HK), FHKAM (MED), FHKCP, MScPD (Cardiff), MRCP (UK), DPD (Wales), DipDerm (Glasgow), PGDipClinDerm (London), MRCP (London), GradDipDerm (NUS), DipMed (CUHK), Kar Wai Alvin Lee, MBChB (CUHK), DCH (Sydney), Dip Derm (Glasgow), MScClinDerm (Cardiff), MScPD (Cardiff), DipMed (CUHK), DCH (Sydney), Kwin Wah Chan, MBChB (CUHK), MScPD (Cardiff), PgDipPD (Cardiff), PGDipClinDerm (Lond), DipMed (CUHK), DCH (Sydney), Kar Fai Victor Lee, MBBS, MRCP (UK), FRCP (Glasgow), FHKCP, FHKAM (Medicine), Kar Wai Phoebe Lam, MBCHB (OTAGO), MRCS (EDIN), MSCPD (CARDIFF)
J Cosmet Med 2022; 6(2): 67-71 https://doi.org/10.25056/JCM.2022.6.2.67Preamjit Saonanon, MD , Krit Rattanakit, MD , Patnapa Vejanurug, MD , Apichaya Thanyavuthi, MD
J Cosmet Med 2021; 5(1): 30-35 https://doi.org/10.25056/JCM.2021.5.1.30