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J Cosmet Dermatol. 2021;00:1–9. wileyonlinelibrary.com/journal/jocd
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1© 2021 Wiley Periodicals LLC
1 | INTRODUCTION
Axillary hyperpigmentation (AH) is a common condition in
dark- skinned individuals that can cause cosmetic concerns, espe-
cially in A sian populations . In a study by James et a l, histopatholo gical
analysis has shown that the most common cause of AH is postin-
flammatory hyperpigment ation (PIH), which in turn can result from
several factors.1 Another study by Evans et al pointed out that ax-
illary tissue differs from other body tissues.2 Axillary tissue consti-
tutes extra hair follicles, extra sweat glands, extra sebaceous glands,
Received: 24 November 2020
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Revised: 20 Ja nuary 2021
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Accepted: 2 Februar y 2021
DOI: 10.1111/jocd.13981
ORIGINAL CONTRIBUTION
Comparison between the use of intense pulsed light and
Q- switched neodymium- doped yttrium aluminum garnet laser
for the treatment of axillary hyperpigmentation
Watinee Amornpetkul MD1 | Silada Kanokrungsri MD1,2 |
Nanticha Kamanamool MD, PhD3 | Montree Udompataikul MD1 |
Salinee Rojhirunsakool MD, MSc1,2
1Skin Center, Faculty of M edicine,
Srinakharinwirot University, Bangkok,
Thailand
2Graduate School, Srinakharinwirot
University, Bangkok, Thailand
3Department of Preventive and Social
Medicine, Srinakharinwirot University,
Bangkok, Thailand
Correspondence
Salinee Rojhirunsakool, Graduate School,
Srinak harinwirot University, 114 Soi
Sukhumvit 23, Khlong Toei Nuea , Watthana,
Bangkok, Thailand.
Email: salinee.roj@gmail.com
Funding information
Srinakharinwirot University
Abstract
Background: Axillary hyperpigmentation (AH) is a condition in which axillary skin is
darker than the adjacent areas. To date, there is no standard treatment for AH. The
Q- switched neodymium- doped yttrium aluminum garnet 1064- nm(QS) laser and in-
tense pulsed light (IPL) are two effective modalities for the treatment of pigmentary
disorders; however, the efficacy and safety levels of both treatments for AH have not
yet been compared in a controlled study.
Aims: To evaluate and compare the efficacy and safety of the QS laser and IPL in the
treatment of AH.
Methods: A randomized, split- side study was conducted on 22 subjects; all subjects re-
ceived a total of five split- side treatments every 2 weeks. The efficacy was determined
using the melanin index (MI), color chart level using the Pantone SkinTone™ Guide, im-
provement grading scale (IGS), and patient satisfaction scores at weeks 2, 4, 6, 8, and 10.
Results: The results showed that there was no significant difference in MI, color chart
level, IGS, and patient satisfaction scores between the two treatments. Both treat-
ments significantly improved AH after three sessions. However, the pain score was
lower for IPL treatment. The adverse effects were transient and were found after IPL
treatment in one participant (4.45%) who developed hyperpigmentation and another
participant (4.45%) who developed erythema.
Conclusions: Intense pulsed light therapy is safe and effective for the treatment of
AH, with no significant difference in the outcome compared with QS laser treatment.
KEY WORDS
axillary hyperpigmentation, intense pulsed light, PIH, postinflammatory hyperpigmentation,
Q- switch Nd: YAG 1064 nm
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AMORNPETKU L ET AL.
and higher transepidermal water loss values that cause weaker skin
barriers. Moreover, the axilla is a flexural area susceptible to con-
stant skin friction, chemical exposure, and frequent shaving, which
can damage the skin tissue and cause irritation, causing PIH.2,3
To date, there is no standard treatment for AH, and studies on
its treatment are limited.4,5 Topical whitening agents are most fre-
quently used for this condition. However, variability in ef ficacy, pro-
longed treatment, and local irritation can hinder the use of these
topical agents. Currently, lasers and energy- based devices have a
great role in the treatment of hyperpigmentation. For the axillary
area, only the Q- switched neodymium- doped yttrium aluminum
garnet 1064- nm wavelength (QS) laser method has been studied.
Robredo and Ghannam et al have shown that QS is clinically effec-
tive for the treatment of AH.5,6 The observational study conducted
by Robredo IGC involved nine patient s who underwent a total of
four sessions of QS treatment every 2 weeks.6 The results were ex-
cellent in 33.3% of patients, and 55.5% of patients showed signifi-
cant improvement, with no side ef fect s. Ghannam et al conducted
an obser vational study in 17 patients, in whom QS treatment was
performed ever y 2 weeks. The number of treatments varied be-
tween 3 and 12 sessions. The treatment results showed a good im-
provement score of 4 ± 0.44 (51% to 75% change), with one patient
developing hypopigmentation. The QS mechanism of ac tion is the
generation of nanosecond- range laser pulses that results in rapid
thermal expansion and fragmentation of the targeted melanosome.
Omi et al demonstrated the effect of low- fluence QS, which can re-
duce melanin granules and melanosomes in patients with melasma,
as revealed by a histologic study.7 Meanwhile, no study in the liter-
ature has described intense pulsed light (IPL) as a treatment for AH.
Intense pulsed light has been widely used as a treatment for hy-
perpigmentation, including PIH. According to recent studies, PIH
can have both epidermal and dermal pigmented components.8 IPL,
which is a broad spectrum of light, can target various chromophores
in the skin, including melanin and hemoglobin. It has been shown to
improve various pigmented lesions, especially epidermal pigmenta-
tion.9- 14 Although there is no evidence- based information supporting
the use of IPL on the axillary area, there are several existing studies
that have used IPL as a treatment for pigmented lesions, especially
on the facial area.1 0- 1 5 Additionally, these studies have demonstrated
its good outcomes. Park et al conducted an observational study
using IPL to treat facial PIH in 25 patients. The study revealed good
improvements (>50% improvement) in 23 patients (92%). Moreover,
IPL has also been used as adjunctive therapy for PIH. For example,
Siadat et al conducted a study on 14 patients to compare modified
Kligman's formula alone and modified Kligman's formula combined
with IPL treatment in postburn hyperpigmentation.16 Modified
Kligman's formula combined with IPL treatment showed clinical
improvement score (>50%) in 78% of subjects compared with 31%
for modified Kligman's formula alone, and higher satisfaction scores
were rated by patients. Based on previous literature supporting the
use of IPL for hyperpigmentation, this study aimed to evaluate and
compare the efficacy and safety levels of IPL and QS to determine an
effective and safe treatment for AH in the future.
2 | MATERIALS AND METHODS
This was a randomized, experimental, split- side controlled, and
assessor- blinded study. The study protocol and informed consent
documents were approved by the Ethical Committee of the Strategic
Wisdom and Research Institute. The par ticipants understood the re-
quirements of the study and voluntarily signed an informed consent
document prior to participation.
2.1 | Subject selection
Twenty- two subjects were enrolled in the study. The participants
were patients with AH aged between 20 and 60 years. The axillary
skin was evaluated for skin color level using the Pantone SkinTone™
Guide. The inclusion criteria were participants with axillary skin
darker than the normal periaxillary skin by at least two levels. The
exclusion criteria included the following: (a) participants with sys-
temic diseases, skin diseases on the axillae, acanthosis nigricans, or
skin diseases that correlated with abnormal hyperpigmentation (eg,
Riehl melanosis, lichen planus pigmentosus); (b) participants receiv-
ing heavy metals (eg, silver), chemotherapy, or antiretroviral drugs
that can cause hyperpigment ation; (c) par ticipants who are preg-
nant or breastfeeding; (d) par ticipants with ongoing treatment with
topical lightening agents (eg, vitamin C, hydroquinone, or retinoids
within 2 weeks prior to the study); and (e) participants who under-
went laser or procedural treatments on the axillary area 8 weeks
prior to the study. Participants experiencing shoulder pain or stif f-
ness were also excluded due to potential difficulty in performing the
treatments and evaluations.
2.2 | Treatment protocol
All participant s received both treatments, with a random allocation
of one side of the axilla to the IPL treatment and the other side
to the QS treatment. The study design comprised a total of five
treatments every 2 weeks (weeks 0, 2, 4, 6, and 8) and a follow-
up session 2 weeks after the last treatment (week 10). The sub-
jects were instructed to shave their axillary hair 1 day prior to the
treatments. Before the treatment procedure, the axillary skin was
cleaned with water, and any remaining hair was shaved off. The
IPL (Lumecca®; InMODE, Lake Forest, CA, USA) treatment set-
tings using the handpiece (550- 120 0 nm) was set at 30- mm spot
size, single- shot frequency, and 5- 8 J/cm2 fluence, with 1 pass
treatment. The endpoint was mild erythema. The QS (MedLite C6;
HOYA ConBio, Fremont, CA, USA) treatment setting included a
spot size of 6 mm, frequency of 10 Hz, and fluence of 2.0- 2.5 J/
cm2, with 3- 5 pass treatments, until the skin appeared of mild ery-
thema, without petechiae.
In this study, participants could continue using any products (eg,
cleansers, over- the- counter deodorants) that had been used for lon-
ger than 3 months and had not caused any signs of dermatitis or
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AMORNP ETKUL E T AL.
irritation. However, any new products were not allowed. Before the
day of treatment, par ticipants were instructed to shave the axillar y
hair and were not allowed to use any other epilation methods (eg,
plucking, waxing, or hair removal laser).
2.3 | Clinical assessments
Clinical assessments were evaluated at baseline (week 0), before
each treatment (weeks 2, 4, 6, and 8), and at the follow- up visit
(week 10). Photographs of the axillar y area were taken using a
standard photographic setting. Using the improvement grading
scale (IGS), the skin conditions were evaluated by two dermatolo-
gists who were not involved in this study. They evaluated the im-
provement s using randomly selected photographs of the visits and
then compared the photographs with those taken at the baseline.
The grading was per formed using a 5- point scale, with 1 = little or
no improvement (0%– 10% change), 2 = minute improvement (11%-
25% change), 3 = fair improvement (26%- 50% change), 4 = good
improvement (51%- 75% change), and 5 = excellent improvement
(>75% change).
The change in skin color was also assessed using the Pantone
SkinTone™ Guide, which is coded by a 4- digit alphanumeric number
(Figure 1). The first two positions (digits) reflect the hue or under-
tone of the skin (Y = yellow, R = red), while the last two positions
(01- 15) represent the lightness or darkness of the skin. The larger
the number, the darker the skin tone. The subject's axillary skin was
assessed by two dermatologists blinded to the study and was re-
corded as digit number codes at ever y visit to define the changes in
the skin color.
2.4 | Melanin index
The MI was assessed at baseline, before each treatment, and at
the follow- up visit. The measurements were performed using the
Mexameter MX 16® (Courage + Khazaka Electronic, Cologne,
Germany).17- 19 Each axilla was divided into four quadrants, and the
measurement was recorded from the middle of the axilla plus the
middle of each quadrant area to reflect the average value change.
Furthermore, to ensure the same spot measurements at every
visit, the areas for measurement were mapped out on a transpar-
ent film as a frame of reference for measurements at the following
visits.
2.5 | Subject's satisfaction
The participant 's satisfaction level was assessed at 2 weeks after the
last treatment (week 10). Using a visual analog scale (VAS) of 0- 10,
a satisfaction range from “not satisfied” (0) to “very satisfied” (10)
was obtained.
2.6 | Pain score and adverse effects
Pain scores were recorded after every treatment visit using the
VAS ranging from 0 (for no pain at all) to 10 (for unbearable pain).
The adverse effects of the treatments were noted by the par tici-
pants’ own reports and through the physician's evaluation. Both
the immediate adverse events (the side effects observed dur-
ing the treatment visits) and the late adverse effects (the side
FIGURE 1 Pantone SkinTone™
Guide
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AMORNPETKU L ET AL.
effects observed at the next visit) were recorded, including signs
of burning, erythema, erosion, petechiae, blister, depigmentation,
and hyperpigmentation. Every outcome was recorded on the split
side.
2.7 | Statistical analyses
Categorical variables of baseline characteristics are presented as
frequency and percentage, whereas continuous variables are pre-
sented as mean ± standard deviation. A paired t- test was used
to compare the average mean for continuous data between the
two treatment methods. A mixed linear model was used to com-
pare the mean for continuous data between the baseline visit and
every other visit for the same axillary group. Statistical analyses
were performed using STATA version 13 (StataCorp). A P- value of
.05 or less was considered statistically significant.
3 | RESULTS AND DISCUSSION
3.1 | Results
Twenty- two subjects with AH were recruited and randomly allo-
cated a side of their axilla for each treatment (QS or IPL). Six sub-
jects missed the last follow- up visit due to the coronavirus 2019
(COVID- 19) lockdown. All participants were women, with 2 (9.1%) of
the Fitzpatrick skin type III and 20 (90.9%) of skin type IV. The mean
FIGURE 2 Improvement grading scale
of the IPL and the QS group. * Significant
differences (P <.05) between baseline and
the follow- up visit. †P- value between t wo
treatments. IPL , intense pulsed light; QS,
Q- switched neodymium- doped yttrium
aluminum garnet 1064- nm wavelength
laser
FIGURE 3 Thirty- two- year- old woman with AH is randomly treated with IPL (right axilla) and QS laser (lef t axilla). (A, C) At baseline. (b,
d) Two weeks after five treatment sessions (week 10). IPL, intense pulsed light; QS, Q- switched neodymium- doped yttrium aluminum garnet
1064- nm wavelength laser; AH, axillary hyperpigmentation
(A) (B) (C) (D)
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AMORNP ETKUL E T AL.
age of the subjects was 30.64 ± 9.65 years. The causes of AH in the
participants were the use of deodorants, preceding dermatitis, hair
removal procedures, and idiopathic conditions. The baseline aver-
age MI of the axillary area was 533.64 ± 28.78 and 533.63 ± 31.55
in the IPL and QS groups, respectively, which was not significantly
different (P =.999). The average score of skin color level measured
by Pantone SkinTone™ of the axillary area was 8.41 ± 2.17 in the IPL
group and 8.27 ± 1.98 in the QS group. There was no significant dif-
ference between the two groups (P =.266).
3.2 | Improvement grading scale
Both treatments demonstrated significant improvement in AH
(Figure 2). The IGS of the IPL- treated side showed significant im-
provement at week 6 (after three treatments). After five treatments
(week 10), the IGS of the IPL group according to a physician's as-
sessment was 2.35 ± 1.01 (25% improvement). For the QS group, a
significant improvement in the IGS was also found at week 6 (af ter
three treatments). The IGS of the QS- treated side was 2.4 ± 1.02
(25% improvement) at the end of the study (week 10). The IGS be-
tween the two treatment groups showed no significant difference
(P =.879). Figures 3 and 4 demonstrate clinic al photographs of rep-
resentative subjects at baseline and the end of study.
3.3 | Skin color level
The skin color level assessment using the Pantone SkinTone™ Guide
for the IPL group showed a reduction from 8.41 ± 2.17 at baseline
to 7.47 ± 1.58 at the end of the study (week 10). A significant differ-
ence in the skin color level from baseline (P <.001) was obser ved at
weeks 8 and 10 (after treatments 4 and 5). The QS group's average
skin color level also decreased from the baseline level of 8.27 ± 1.98
to 7.73 ± 1.71 and 7.58 ± 1.57 at weeks 8 and 10, respectively, which
shows a significant difference (P =.011 and P =.005, respectively)
compared with the baseline value. When comparing the two treat-
ments, the skin color level did not show any statistically significant
differences bet ween the IPL- treated and the QS- treated groups
(0.673) (Figure 5).
3.4 | MI
In the IPL group, the MI gradually decreased from 533.64 ± 28.78
at baseline to 528.37 ± 31.97 at week 10. The reduction in
MI from baseline showed a statistical difference (P =.020) at
week 10. Similarly, for the QS group, the MI decreased from
533.63 ± 31.55 to 529.06 ± 29.13. After five treatments (week
10), the results indicated a statistical significance (P =.007) com-
par ed with the baseline. More ove r, th e re duction in the MI for the
two groups showed no significant difference (P =.811) at any visit
(Figure 6).
3.5 | Subject satisfaction level, pain score, and
adverse effects
The mean subject satisfaction score assessed using VAS for the
IPL and the QS treatment groups was 8.31 ± 1.7 and 8.22 ± 1 .7,
FIGURE 4 Twenty- five- year- old woman with AH is randomly treated with IPL (right axilla) and QS laser (left axilla). (A, C) At baseline
(B, D). Two weeks after five treatment sessions (week 10). IPL , intense pulsed light; QS, Q- switched neodymium- doped yttrium aluminum
garnet 1064- nm wavelength laser; AH, axillary hyperpigmentation
(A) (B) (C) (D)
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AMORNPETKU L ET AL.
respectively, which does not show any significant difference
(P =.707). The treatment- related pain in the QS group was higher
than that in the IPL group. In QS- treated group, the mean subjec t
pain scores from the first to fifth treatments were 2.25, 1.89, 1.45,
1.75, and 1.03, and the pain scores of those in the IPL- treated
group were 1.09, 1.22, 0.86, 1.39, and 0.82, respectively. Adverse
effects were observed in the IPL- treated group, where one par-
ticipant (4.45%) developed erythema 24 h after the treatment,
and another participant (4.45%) developed hyperpigmentation,
which was observed at 2 weeks after the second IPL (Figure 7).
Hyperpigmentation showed improvement at the next visit after a
repeated IPL treatment and did not result in a dropout of the pa-
tient. Conversely, there were no detectable adverse effects in the
QS group.
4 | DISCUSSION
The results of this randomized, split- side, controlled study dem-
onstrated that both the IPL and QS laser treatments are effec tive
and have comparable ef ficacy in the treatment of AH. After three
sessions, the IGS revealed a significant improvement from both
treatments. The skin color level significantly improved after four
sessions (week 8), with the mean MI significantly decreasing after
five sessions (week 10). The subject satisfaction levels were com-
parably high for both treatments. Adverse effects were obser ved in
two participants (9%) in the IPL- treated group. The pain score, how-
ever, was higher in the QS group.
To our knowledge, there is no previous study in the literature
that has researched the use of IPL therapy for the treatment of AH.
Nevertheless, IPL has been extensively studied for various cases of
hyperpigmentation in the facial area. Park et al conducted a pro-
spective study using IPL to treat facial PIH in skin ty pes III– V,12 with
four treatments every week, followed by four treatments every
2 weeks. The results of the study showed that 92% of participant s
had more than 50% improvement, as assessed using the Validated
Investigator Global Assessment. Another study by Augustyniak
et al used IPL in the treatment of facial and neck hyperpigmenta-
tion,14 with three treatments every 3 weeks. Assessments using
the median MI showed a significant reduction of 11% (184 ± 3 9. 6
to 162.2 ± 31.0) after three sessions. Although the present study
also used IPL therapy to treat hyperpigmentation, previous studies
FIGURE 5 Skin color level using the
Pantone SkinTone™ Guide of the IPL and
the QS group. * Significant differences
(P <.05) between baseline and the
follow- up visit. †P- value between two
treatments. IPL , intense pulsed light; QS,
Q- switched neodymium- doped yttrium
aluminum garnet 1064- nm wavelength
laser
FIGURE 6 Melanin index of the
IPL and the QS group. * Significant
differences (P <.05) between baseline and
the follow- up visit. †P- value between t wo
treatments. IPL , intense pulsed light; QS,
Q- switched neodymium- doped yttrium
aluminum garnet 1064- nm wavelength
laser
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AMORNP ETKUL E T AL.
have shown better improvements in pigmentation after IPL ther-
apy. It is possible that the discrepancy in result s is due to the
differences in the anatomical areas that were treated. The facial
area is thin, and most of the pigmentation is frequently caused by
ultraviolet- induced melanogenesis. Moreover, the AH usually de-
velops due to irritation and PIH, which causes the adaptation of
axillar y skin to be thicker and darker.2,20 Therefore, the difference
in location and pathogenesis might lead to a lower response of the
axillar y area to energy- based devices compared with that of the
facial area.
The efficacy of QS for the treatment of AH has been evaluated
by Ghannam et al, who conducted an observational study with
17 patients who underwent QS laser treatment every 2 weeks.5
The number of treatments varied between 3 and 12 sessions. The
treatment results showed a good improvement score of 4 ± 0.4 4
(51%– 75% change), with one patient developing hypopigmentation
(5.9%). Another study by Robredo IGC demonstrated that 33.3%
of the participants exhibited excellent improvement and 55.5%
showed good improvement with no side effects, using the Global
Aesthetic Improvement Scale satisfaction assessment.6 Our study
also showed the efficacy of the QS in the treatment of AH with
a 25% improvement using IGS. In this study, we used a Pantone
SkinTone™ color level guide and a Mexameter, which also showed
significant improvement of AH after QS treatment. Although our
levels of improvement seem to be lower in comparison, it demon-
strates a visible change in clinical results. The use of different mod-
els of laser machines, different operators, severity of the condition
being treated, and skin types in different races can cause the results
to vary between studies. However, our study also demonstrated
that QS managed to obser vably improve the AH condition after 3- 4
treatment sessions.
In the present study, the minimum number of treatments for a
significant improvement was observed at three sessions when as-
sessed using IGS. However, when assessed using skin color level and
MI, a significant improvement was seen only af ter sessions 4 and 5.
This finding correlates with a previous study by Ghannam et al, who
found a good to excellent improvement af ter a minimum of three
sessions of QS laser.5 Moreover, Robredo IGC observed a marked
reduction in pigmentation after four sessions of QS laser treatment.6
This suggests that a minimum of three or four treatment sessions
are required for a significant reduction in AH for both the IPL and
QS treatments. Furthermore, our study demonstrated that AH im-
proved with an increasing number between three and five sessions
of treatments for both IPL and QS lasers.
Currently, IPL is a widely used procedure in dermatology be-
cause of its cost- effective nature and multiple applications, includ-
ing the treatment of hyperpigmentation. Our study demonstrated
that IPL treatment has comparable efficacy to the QS laser for the
FIGURE 7 Adverse effects of the IPL
treatment; (A) before treatment and (B)
the development of hyperpigmentation
after the second IPL sessions. IPL, intense
pulsed light
(A) (B)
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AMORNPETKU L ET AL.
treatment of AH for ever y outcome criterion. In terms of adverse
effects, there are some concerns in using IPL for individuals of
dark skin t ype, especially in the axillary area. However, this study
observed only one participant (4.45%) who developed hyperpig-
mentation after treatment and one participant (4.45%) who devel-
oped erythema, which was transient and did not yield permanent
sequelae. Moreover, no side effects were observed in the QS-
treated group. In terms of pain during the procedure, the subject s
also rated the pain score for IPL to be much lower than that for
the QS laser. With regard to the side effects of IPL when used
in dark skin, such as skin burn and hyperpigmentation, this study
demonstrated that IPL had few reversible side effec ts when used
in the axillary area, but was not significantly different from QS
laser treatment.
Some limitations are present in this study. First, because of
COVID- 19, some participants could not attend the last scheduled
visit at week 10. Therefore, we analyzed the outcomes using the
intention- to- treat method. Second, the participants in this study
were all women. Whether the results of this study can be replicated
with men will require further investigation. We also suggest that fur-
ther studies should include a large number of subjec ts and expand
the duration of the follow- up period. Future studies on combined
treatments, such as the use of topical lightening agent s or chemical
peeling with laser therapy, should be conduc ted to improve the re-
sponse to treatment.
In conclusion, IPL is as ef fective and safe as the QS laser for the
treatment of AH in patients with skin types III– IV.
COMPLIANCE WITH ETHICAL STANDARDS
This study was approved by the Clinical Research Ethical Commit tee
of Srinakharinwirot University on January 15, 2020, with Certificate
No. SWUEC- 311/2562F. The study protocol followed the guidelines
of the 1964 Declaration of Helsinki.
ACKNOWLEDGMENTS
We would like to thank the Faculty of Medicine, Srinakharinwirot
University, for providing us with the research grant. Additionally, we
would like to thank Astraco Medical Net works Ltd. for providing the
IPL machine.
CONFLICT OF INTEREST
The researchers declare no conflict of interest.
AUTHOR CONTRIBUTIONS
WA and SR contributed to conceptualization, methodology, and data
collection. NK, WA, and SR performed formal analysis. WA and SR
prepared the original draft. SK, MU, and SR reviewed and edited the
manuscript. SR underwent study supervision. All authors read and
approved the paper.
INFORMED CONSENT
Informed consent was obtained from all individual participants in-
cluded in the study.
DATA AVAIL ABI LIT Y S TATEM ENT
The data that support the findings of this study are available from
the corresponding author upon reasonable request.
ORCID
Silada Kanokrungsri https://orcid.org/0000-0003-0837-2725
Salinee Rojhirunsakool https://orcid.org/0000-0001-9284-4355
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How to cite this article: Amornpetkul W, Kanokrungsri S,
Kamanamool N, Udompataikul M, Rojhirunsakool S.
Comparison between the use of intense pulsed light and
Q- switched neodymium- doped yttrium aluminum garnet
laser for the treatment of axillary hyperpigmentation. J
Cosmet Dermatol. 2021;00:1– 9. https ://doi.or g/10.1111/
jocd.13981
