Combined Therapy Using Q-Switched Ruby Laser andBleaching Treatment With Tretinoin and Hydroquinone
for Acquired Dermal Melanocytosis
A KIRA M OMOSAWA , MD, n K OTARO Y OSHIMURA , MD, n G ENTARO U CHIDA , MD, n
K ATSUJIRO S ATO , MD, n E MIKO A IBA , MD, n D AISUKE M ATSUMOTO , MD, n
H ISAYO YAMAOKA , MD, n S AORI M IHARA , P H D, w K ATSUHIKO T SUKAMOTO , MD, z
K IYONORI H ARII , MD, n TAKAO A OYAMA , P H D, § AND TATSUJI I GA , P H D §Department of Plastic and Reconstructive Surgery, University of Tokyo,wBiomaster, Inc.,zDepartment of Dermatology,
Yamanashi Prefectural Central Hospital, Yamanashi, and §Department of Pharmacy, University of Tokyo, Graduate
School of Medicine, Tokyo, JapannBACKGROUND AND OBJECTIVE. Acquired dermal melanocytosis(ADM; acquired bilateral nevus of Ota-like macules) is known
for its recalcitrance compared with Nevus of Ota, and weassume that one of the reasons is a higher rate and degree of
postinflammatory hyperpigmentation (PIH) seen after laser
treatments.
METHODS. Topical bleaching treatment with 0.1% tretinoin
aqueous gel and 5% hydroquinone ointment containing 7%
lactic acid was initially performed (4 to 6 weeks) to discharge
epidermal melanin. Subsequently, Q-switched ruby (QSR) laser
was irradiated to eliminate dermal pigmentation. Both steps
were repeated two to three times until patient satisfaction was
obtained (usually at a 2-month interval for laser sessions). This
treatment was performed in 19 patients with ADM. Skin biopsy

was performed in six cases at baseline, after the bleaching
pretreatment, and at the end of treatment.
RESULTS. All patients showed good to excellent clearing after
two to three sessions of QSR laser treatments. The totaltreatment period ranged from 3 to 13 (mean of 8.3) months.
PIH was observed in 10.5% of the cases. Histologically,
epidermal hyperpigmentation was observed in all specimens
and was dramatically improved by the topical bleaching
pretreatment.
CONCLUSION. QSR laser combined with the topical bleaching
pretreatment appeared to treat ADM consistently with a low
occurrence rate of PIH and lessen the number of laser sessions
and total treatment period and may also be applied to any otherlesions with both epidermal and dermal pigmentation.

A. MOMOSAWA, MD, K. YOSHIMURA, MD, G. UCHIDA, MD, K. SATO, MD, E. AIBA, MD, D. MATSUMOTO, MD,
H. YAMAOKA, MD, S. MIHARA, PHD, K. TSUKAMOTO, MD, K. HARII, MD, T. AOYAMA, PHD, AND T. IGA, PHD HAVE
INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS.

NEVUS OF OTA, first described in 1939 by Ota andTanino1 as nevus fuscocaeruleus ophthalmo-maxillaris, is usually unilaterally located in the area
innervated by the ophthalmic and maxillary branchof the trigeminal nerve. A typical nevus of Ota is a flat
blue-black or slate-gray macule intermingled withsmall, flat, and brown spots. Pigmented macules arealso often present in ocular, oral, and nasal mucous
membranes. On the other hand, acquired bilateralnevus of Ota-like macules (Hori’s nevus) is a pigmented lesion involving bilateral grayish brown facialmacules that was first reported by Hori et al.2 in 1984.
This condition and similar ones have been referred toAddress correspondence and reprint requests to: Kotaro Yoshimura,MD, Department of Plastic and Reconstructive Surgery, Graduate
School of Medicine, University of Tokyo, 7-3-1, Hongo, Bunkyo-Ku,
Tokyo 113–8655, Japan, or e-mail: yoshimura@cosmetic-medicine.jp.

as acquired dermal melanocytosis (ADM) by someJapanese dermatologists.3,4 ADM onsets later in life,
usually after the age of 20 years, and represents bilateralinvolvements, with the malar regions almost always
affected, and a lack of mucosal and optic involvement.2 It is rare in whites but is relatively common in
Asian females and is seen much more frequently thannevus of Ota.5 There is a report that it occupied 7.5%of cosmetic skin complaints in Japan.6 Clinically, it canbe easily distinguished from nevus of Ota by bilateralpresentation, spot distribution, and difference in color,whereas in some atypical cases, it can be misdiagnosed
as melasma. ADM on bilateral cheeks usually has around spot distribution and is more grayish in color
than melasma, although we experienced several cases
in which melasma-like lesions were initially seen on
both cheeks, and round grayish spots were detected
only after tretinoin bleaching was completed.

r 2003 by the American Society for Dermatologic Surgery, Inc.  Published by Blackwell Publishing, Inc.
ISSN: 1076-0512/03/$15.00/0  Dermatol Surg 2003;29:1001–1007

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The authors previously described an aggressive andoptimal use of tretinoin along with hydroquinone forvarious kinds of skin hyperpigmentation.7–9 This
topical bleaching treatment was very effective forremoval of epidermal pigmentation. Therefore, we
tried the bleaching pretreatment before Q-switchedruby (QSR) laser for ADM in order to eliminate
epidermal hyperpigmentation and decrease the risk of
postinflammatory hyperpigmentation (PIH) after QSR
laser treatment. This combination therapy was applied
for patients with ADM, and its efficacy and usefulness
were evaluated.

Methods

Preparation of Ointments
Tretinoin aqueous gels (tretinoin gel) at three different
concentrations (0.1%, 0.2%, and 0.4%) were originally prepared at the Department of Pharmacy, University of Tokyo, Graduate School of Medicine. The
precise regimen of tretinoin aqueous gel was described
before.8 These gels can be prepared relatively easily
because the tretinoin powder (Sigma Chemical,
St. Louis, MO) is commercially available. Aqueous gel
is most suitable for ointment base of tretinoin becauseof its good permeability. An ointment, including 5%hydroquinone and 7% lactic acid (HQ-LA ointment),
and one including 5% hydroquinone and 7% ascorbic
acid (HQ-AA ointment), were also prepared. Plastibase (petrolatum polyethylene ointment base; Taisho
Pharmacology, Osaka, Japan) was used as the ointment base of the HQ-LA ointment, whereas thehydrophilic ointment was used for the HQ-AA ointment. Because tretinoin gel, HQ-LA, and HQ-AA ointments (especially tretinoin gel) are pharmacologicallyunstable, fresh ointments were prepared at least once amonth and were stored in a dark and cool (41C) place.

Evaluations of Results
Photographs were taken for every patient at baseline
and after treatment with a high-resolution digital
camera (Canon EOS-D30). The percentage of pigmentary clearance was evaluated via the photographs by
two experienced plastic surgeons who did not perform
this treatment. The mean data of the pigmentary
clearance of each patient were classified into four
categories: ‘‘excellent’’ (80% or more clearance), ‘‘good’’(50% to less than 80% clearance), ‘‘fair’’ (0% to lessthan 50% clearance), and ‘‘poor’’ (no change or worse).

Patients
Nineteen Japanese patients with ADM were treatedwith our treatment protocol. All patients were women.

29:10:October 2003

The patient age at the start of the treatment ranged
from 24 to 50 years old (mean7SD, 37.978.7). The
age of onset of ADM was 15 to 40 years old(mean7SD, 24.777.5). Pigmented lesions were located bilaterally on the malar area in all 19 cases(100%), on the nose in 4 cases (21%), on the temporal
area in 2 cases (11%), and on the forehead in 1 case(5%). The follow-up time after the final laser session
ranged from 3 to 13 months (mean7SD, 8.373.7).

Treatment Methods
Our treatment was composed of two steps. The firststep was a topical bleaching treatment using tretinoin
gel and hydroquinone ointment (6 to 8 weeks), and thesecond step was QSR laser irradiation. Both steps wererepeated until patient satisfaction was obtained.

Topical Bleaching Treatment
The purpose of this treatment is to improve epidermal pigmentation by accelerating discharge of
epidermal melanin (by tretinoin) and suppressing
new epidermal melanogenesis (by hydroquinone).
The two-phased (bleaching and healing) treatment
was performed as follows.

Bleaching Phase
Both 0.1% tretinoin gel and HQ-LA ointment were
initially applied to the skin lesions twice a day.
Tretinoin gel was carefully applied only on pigmented
spots using a small cotton-tip applicator, whereas HQLA ointment was widely applied with fingers (e.g., allover the face) a few minutes later, after allowing theapplied tretinoin aqueous gel to dry. The method of
ointment application is critical in this aggressive
treatment in order to obtain maximal bleaching effects
with minimal irritant dermatitis. In case severe irritantdermatitis was induced by HQ-LA ointment, HQ-AA
ointment was used instead. Patients were requested tovisit our hospital at 1, 2, 4, 6, and 8 weeks after
starting this treatment and every 4 weeks thereafter.
When the appropriate skin reaction (i.e., mild erythema and scaling) was not observed at 1 week, theconcentration of tretinoin was changed to 0.4%
because 0.2% tretinoin gel was usually not strong
enough to get a sufficient reaction in these cases. The
concentration of tretinoin and frequency of its
application were appropriately modified according to
the skin condition and degrees of erythema andscaling. In most cases, it took 4 to 6 weeks to finish
this phase. In the second bleaching step, tretinoin gelof the final strength used in the first step was used fromthe beginning.

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Healing Phase

Table 1. Clinical evaluations (Clearance of pigmentation)

After the 4- to 6-week bleaching phase, the applicationof tretinoin gel and HQ-LA ointment was discontinued, and application of HQ-AA ointment was used inorder to prevent PIH until the redness was sufficiently
reduced. It usually took 2 to 4 weeks to complete thisphase. Topical corticosteroids were not employed ineither the bleaching or healing phase.

Excellent
Good
Fair
Poor

15/19
4/19
0/19
0/19

Total

78.9%
21.1%
0.0%
0.0%
100.0%

Table 2. Number of QSR laser treatments performed

QSR Laser Treatments
In all patients, topical anesthesia (lidocaine patch;
Penles, Wyeth Lederle Japan Inc., Tokyo, Japan) wasapplied 60 to 120 minutes before the laser treatment.
For QSR 694.5-nm laser (Model IB101; Niic Co.,Tokyo, Japan) treatment, a spot size of 5 mm, a 1-Hz
repeat rate, a pulse duration of 20 ns, and fluences
ranging from 4.0 to 5.0 J/m2 were used. After laser
treatment, topical gentamicin sulfate ointment (Gentacin, Schering-Plough, NJ) was applied twice a day
until a scale or thin crust disappeared (usually for 5 to
7 days). At 2 weeks after laser treatment, applicationof HQ-AA ointment was started.
At 4 weeks after each laser treatment, the topicalbleaching treatment with tretinoin gel of appropriate
concentration (usually same as the final concentrationin the bleaching phase) and HQ-AA ointment werestarted as a pretreatment of the next laser irradiation
and also as a treatment of postlaser PIH in some cases.
In most cases, the bleaching phase for 2 weeks waslong enough, and we can usually estimate the clinicalresult at 8 weeks after each laser treatment. Whensome hyperpigmentation remained, we can go for the
next session. An example of the typical time course
was demonstrated in Figure 1.
Skin biopsy of pigmented regions with a diameter of
2 mm was performed in six cases at baseline, just after
the first bleaching treatment, and at the end of thetreatment. Sections were stained with Masson-Fontana
staining for visualization of melanin granules.

Results

Clinical Results
In the topical bleaching treatment, erythema wasusually seen in a few days, followed by continual

Once
Twice
Three times

0/19
7/19
12/19

0.0%
36.8%
63.2%

scaling during the first week. Erythema and scaling
were usually seen continually throughout the bleaching phase. On the other hand, erythema gradually
declined with time in the healing phase. The differencein color of the macules was usually observed between
before and after the first topical bleaching treatment,
for example, a color change from brown to graybrown or from gray-brown to bluish black, suggesting
clearance of epidermal pigmentation.
All patients showed ‘‘good’’ to ‘‘excellent’’ clearing
after two or three laser treatments without any
complications such as scarring and persistent depigmentation. Fifteen of 19 cases were evaluated as‘‘excellent’’ and the other 4 cases as ‘‘good’’ (Table 1).
No cases were regarded as ‘‘fine’’ or ‘‘poor.’’ QSR laser
treatments were performed twice in 7 of 19 cases, and3 times in the other 12 cases (Table 2). Although PIH
apparently occurred in 2 of 19 cases (10.5%) after the
first laser treatment, PIH was not clearly seen in any
cases after the second and third laser treatments. We
diagnosed pigmentation as PIH at 4 weeks after laser
treatment when the pigmentation got worse than
before or 1 to 2 weeks after laser treatment. The
average treatment period was 24.873.6 (mean7SD)
weeks, and the average number of QSR laser treatment
was 2.6370.5 (mean7SD) times. Although patients
had unpleasing irritant dermatitis during the topicalbleaching treatment, all achieved sufficient satisfaction
with the final results, and they were followed for
8.373.7 (mean7SD) months (3 to 13 months) without any evidence of recurrence. The representative
three cases are shown in Figures 2–4.

Histologic Results
Figure 1. A representative time course of the combined treatment.
Tretinoin is used for 4 weeks in the initial bleaching pretreatment andfor 2 weeks in the following pretreatments. QSR laser treatment isperformed three times, and the total treatment period is 30 weeks.

At baseline, not only dermal melanocytosis but also
epidermal melanosis around the basal layer was seenin all six samples (Figure 5). In the upper dermis,
elongated, slender, and pigment-bearing melanocytic
cells dispersed between the collagen fibers were1004

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Figure 2. Case 1. (A and B) Baseline photos of a 24-year-old woman with ADM. (C and D) Just after the bleaching treatment with tretinoin andhydroquinone. The color change of the macules was moderate, but the histologic change was apparent, as shown in Figure 6. (E and F) Six months
after the third QSR laser treatment. Note the complete clearance of pigmentation.

observed. In addition, all six specimens showeddisappearance of rete ridges. In most cases, epidermalmelanin granules were significantly cleared after the
initial bleaching treatment, whereas dermal pigmentation appeared not to change at all (Figure 6).

Discussion
The first reported treatment of ADM was cryotherapy,10 but it showed an unpredictable result with ahigh risk of permanent scarring and hypopigmentation. Kunachak et al.11 treated ADM using dermabrasion with successful results. Despite its advantage as asingle session procedure, this approach is invasive.12
Therefore, QS lasers are considered to be main
treatments of ADM today as well as nevus of Ota.
Although previous reports of QS laser treatments
showed good clearance of ADM,12–16 it has been
pointed out that PIH and hypopigmentation are
frequently observed afterward. In ADM, it is known
that PIH occurs 2 to 4 weeks after laser irradiation inhigher degrees and frequency than in nevus of Ota.
Kunachak et al.12 employed repetitive treatment
sessions at only 1- to 2-week intervals. They performed
the second laser session before PIH appeared andreported successful clearance of ADM but relatively
high (5.7%) risk of hypopigmentation. Polnikorn
et al.13 and Kunachak and Leelaudomlipi14 both used
QS Nd:YAG laser to treat ADM and reported that therate of PIH was 71% and 50%, respectively. Polnikorn
et al.13 waited for disappearance of PIH before thenext session of laser treatment, which was 3 to 6
months. Lam et al.15 used QS alexandrite laser withthe mean session number of seven, and most patients
showed postlaser PIH. In our own experience using
QSR laser for ADM without any pretreatments, PIH
was almost always observed 2 to 4 weeks after the firstlaser treatment.
The typical color of ADM is grayish brown.2–5 It is
more brownish than typical nevus of Ota (blue black
or slate gray). There are two significant differences inhistology between nevus of Ota and ADM: (1)Melanocytes are distributed diffusely throughout theDermatol Surg

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Figure 3. Case 2. (A) A baseline view of a 29-year-old woman with
ADM. (B) Ten months after the third QSR laser treatment. The clinicalresult was evaluated as ‘‘excellent.’’

Figure 4. Case 3. (A) A baseline view of a 46-year-old woman with
ADM. (B) Three months after the third QSR laser treatment. The resultof the clearance was evaluated as ‘‘good.’’entire dermis in nevus of Ota,17 whereas they arelocated only in the upper dermis in ADM,2 and (2)epidermal hyperpigmentation is not usually seen in

MOMOSAWA ET AL.: COMBINED THERAPY FOR ADM

1005

Figure 5. Histology of ADM before treatments. Both sections
demonstrated epidermal hyperpigmentation around the basal layer,melanocytosis in the upper dermis, disappearance of rete ridges, andslight thinning of the epidermis (Masson-Fontana staining, 100).

nevus of Ota, whereas it is always prominent in ADM;
the latter was not well documented before, but we
confirmed epidermal hyperpigmentation in all specimens examined in this study (Figure 5). The differencein color between nevus of Ota and ADM is due tothese histologic differences. Although nevus of Ota
responds to Q-switched lasers very well,18–22 ADM is
known for its recalcitrance to conventional treatments,13–16 and one of the reasons seems to be a highrate of PIH seen after laser treatments.13–15 The
authors assumed that it was mainly due to the presenceof epidermal hyperpigmentation in ADM.
In addition, all biopsy specimens showed disappearance of rete ridges, whereas surrounding intact
skin had normal rete ridges in some cases. This finding
may clinically mean suppression of both epidermal
turnover and discharge of epidermal melanin and may
be related to the epidermal hyperpigmentation seen in
ADM, whereas the reason for epidermal hyperpigmentation in ADM is not clarified, and we suspect thatthe epidermal hyperpigmentation in ADM is mainly
due to abnormal melanin production by melanocytes
like melasma.
In this study, we confirmed histologically that
accumulated melanin granules around the basal layer
were cleared up after treatment with tretinoin andhydroquinone, but the melanin deposits (dermalmelanocytes) in the dermis appeared not to change in1006

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Figure 6. Histology of ADM in case 1. (A) at baseline and (B) just after the topical bleaching pretreatment. (A) At baseline, the section demonstrated
epidermal hyperpigmentation as well as the scattered dermal melanocytes featuring a highly pigmented, elongated dendritic appearance. (B) Just
after the topical bleaching pretreatment, epidermal pigmentation was significantly improved, whereas the dermal menlanocytosis appeared not tochange at all (Masson-Fontana staining, 200).

ADM (Figure 6). Taken together with our previous
studies,9,23–25 this finding supports our previous
hypothesis for mechanism of this topical bleaching
therapy: Tretinoin acts as a discharger of epidermalmelanin by accelerating epidermal turnover andpromoting keratinocytes proliferation, whereas hydroquinone suppresses new melanin production by
epidermal melanocytes.
It is considered that the present combination
therapy with QSR laser and the aggressive bleachingtreatment has the following advantages: (1) highefficiency of the QSR laser treatment in improving
dermal pigmentation (after the pretreatment removing
epidermal pigmentation [basal melanosis], the laser
radiation can be expected to more efficiently get to thedermis because its energy absorption by epidermalmelanins is thought to be lower), and (2) decreasing
the rate of PIH (we assume that if there is a significant
amount of epidermal pigmentation, considerable
inflammation would be induced in the entire epidermis, resulting in occurrence of PIH usually 2 to 4
weeks after laser irradiation). In this sense, therefore,
the pretreatment to discharge epidermal melanins
seems to be quite important. Indeed, with thebleaching pretreatment, the frequency of PIH after
initial laser treatment was as low as 10.6%, which issignificantly lower than other studies. In addition, PIH
was not clearly detected after the second or third laser
treatment.
Nevus of Ota, which can usually be well treated byseveral sessions of QSR laser, has predominantly
dermal pigmentation. This is because, unlike ADM,
it does not have significant epidermal hyperpigmenta-

tion, which induces PIH after laser treatments andmakes it more difficult to treat consistently. Therefore,
we prefer the topical bleaching therapy with tretinoin
and hydroquinone for epidermal pigmentation and QS
lasers for dermal pigmentation, with the exceptions ofhyperkeratotic lesions such as solar lentigines on
extremities and trunks (these lesions have thickstratum corneum) that we treat with a QSR laser first
and tretinoin bleaching for PIH induced by QSR laser
treatment. It may be desirable to perform laser
treatments after pretreatment of epidermal pigmentation for lesions with both epidermal and dermal
pigmentation, such as ADM, friction melanosis,
dermal melasma, and hyperpigmentation after atopic
dermatitis. The topical bleaching therapy can treat
almost any kinds of epidermal hyperpigmentation
without hyperkeratosis, including PIH and melasma,
which can not be treated with lasers.
For treatment of PIH after laser treatments, topicaltretinoin and hydroquinone appeared to be best, as weand others15 did, although the bleaching protocols are
not the same. Otherwise, we can wait for spontaneousclearance of PIH; however, the clearance is notguaranteed, and intervals between laser sessions
become much longer, such as 3 to 6 months.13 PIH is
one of the easiest pigmented lesions to treat with the
topical bleaching treatment,8 and in this study, a mild
treatment with tretinoin for only 2 weeks was usually
sufficient, whereas hydroquinone was used continuallyfor over 1 month. Even if the pretreatment isperformed, intervals between laser treatments can beshortened up to 6 to 8 weeks, therefore leading toshortening of the total treatment period comparedDermatol Surg

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with methods waiting for spontaneous disappearanceof PIH.

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