percutaneous collagen induction versus full-concentration...
TRANSCRIPT
Percutaneous Collagen Induction Versus Full-ConcentrationTrichloroacetic Acid in the Treatment of Atrophic Acne Scars
TAHRA LEHETA, MD,� AMIRA EL TAWDY, MD,� RANIA ABDEL HAY, MD,� AND SALLY FARID, MSCy
BACKGROUND Percutaneous collagen induction (PCI) promotes removal of damaged collagen andinduces more collagen immediately under the epidermis. The chemical reconstruction of skin scars(CROSS) method is a focal application of full-concentration trichloroacetic acid (TCA) to atrophic acnescars. The CROSS method has the advantage of reconstructing acne scars by increasing dermalthickening and collagen production.
OBJECTIVE To compare the safety and efficacy of PCI and the 100% TCA CROSS method for thetreatment of atrophic acne scars.
MATERIALS AND METHODS Thirty participants were randomly equally divided into two groups; group 1underwent four sessions (4 weeks apart) of PCI, and group 2 underwent four sessions (4 weeks apart) of100% TCA CROSS.
RESULTS Acne scarring improved in 100% of patients. Scar severity scores improved by a mean of68.3% (po.001) in group 1 and a mean of 75.3% (po.001) in group 2. The difference in the degree ofimprovement was not statistically significant between the groups (p = .47).
CONCLUSIONS PCI and 100% TCA CROSS were effective in the treatment of atrophic acne scars.
The authors have indicated no significant interest with commercial supporters.
Acne scarring causes problems cosmetically and
psychologically. Unfortunately, there has been
no standard treatment option for the treatment of
acne scars. Various therapeutic options have been
described with variable clinical outcomes and
complications, such as surgical techniques (punch
graft, punch excision, subcision), resurfacing tech-
niques (dermabrasion, ablative laser treatment,
chemical peels), nonablative laser treatment, auto-
logous fat transfer, and injection of dermal fillers.1
Skin needling, also known as percutaneous collagen
induction (PCI), with Dermaroller (a needling tool) is
an addition for managing postacne scars. The treat-
ment is an office procedure2 that creates thousands of
microclefts through the epidermis into the papillary
dermis. These tiny wounds in the papillary dermis
create a confluent zone of superficial bleeding that
is a powerful stimulus to initiate the normal process
of wound healing3 with release of several growth
factors that stimulate the migration and proliferation
of fibroblasts that promote collagen deposition.4
Tissue remodeling continues for months after the
injury.5 Previous experiences with PCI in treating acne
scarring have demonstrated its effectiveness.2,4
Liebl6 explained the PCI mechanism of action and
stated that the fine microneedles do not create a
wound in the classic sense. When microneedles
penetrate the skin, cells react with a demarcation
current that is additionally increased by the needles’
own electrical potential. The wound healing process
is cut short, and this bioelectricity triggers a cascade
of growth factors that stimulate the healing phase.
Jaffe has proven this hypothesis.7
Chemical reconstruction of skin scars (CROSS) is a
technique consisting of the focal application of high
trichloroacetic acid (TCA) concentrations by press-
ing hard on the entire depressed area of atrophic
& 2011 by the American Society for Dermatologic Surgery, Inc. � Published by Wiley Periodicals, Inc. �ISSN: 1076-0512 � Dermatol Surg 2011;37:207–216 � DOI: 10.1111/j.1524-4725.2010.01854.x
2 0 7
�Dermatology Department, Faculty of Medicine, and yStudent Hospital, Cairo University, Cairo, Egypt
scars using a sharpened wooden applicator, max-
imizing the effect of TCA with rapid healing and
lower complication rate.8 Several studies have shown
the excellent effect of the CROSS method in the
treatment of acne scars.1,8–10 Improvement of acne
scars after TCA CROSS occurs because of coagula-
tive necrosis in the epidermis, necrosis of dermal
collagen, and fragmentation of elastin fibers in the
papillary dermis.11
Our aim was to compare the efficacy of PCI (using
Dermaroller) and high concentrated TCA CROSS
as different therapeutic modalities for the treatment
of atrophic acne scars. To our knowledge, there is no
reported study comparing the efficacy of these
techniques in the management of atrophic acne
scars.
Patients and Methods
This prospective, randomized study compared the
efficacy of PCI and 100% concentrated TCA CROSS
in the treatment of atrophic acne scars. The
Dermatology Research Ethical Committee, Faculty
of Medicine, Cairo University approved the study.
All patients provided written informed consent.
Because of the two interventions used, blinding of
study participants could not be achieved. The
assessor was blinded to the intervention used.
Thirty patients (16 men, 14 women) with different
types of atrophic acne scars were enrolled in this
study. The mean duration of acne scars was 4.8 years
(range 2–10 years). Exclusion criteria were systemic
retinoids or immunosuppressive drug intake during
the previous 6 months, coagulation defects or blood
diseases, evidence or history of keloid scars, preg-
nancy or lactation, and unrealistic expectations.
Postacne atrophic scar types in each patient were
classified according to Jacob and colleagues12 (Table
1). Participants were randomly divided into two
equal groups; group 1 (15 patients) underwent PCI
treatment, and group 2 (15 patients) underwent TCA
100% CROSS. Each patient received four sessions of
treatment at 4-week intervals.
Patients were instructed to avoid anticoagulant
medications such as aspirin and nonsteroidal anti-
inflammatory drugs (NSAIDs) for at least 1 week
before the session and to start using topical retinoid
and hydroquinone 4% 2 weeks before each session,
stopping 2 days before the session to avoid
irritation to the skin.
Group 1 (PCI Plus Dermaroller)
Local anesthetic cream (eutectic mixture of prilo-
caine and lignocaine) was applied to the face under
occlusion for approximately 45 to 60 minutes before
the procedure. Patients were treated using the
needling tool (Dermaroller MF 8, Horst Liebl CEO,
Fresenheim, France), which is a sterile plastic
cylinder with needles protruding from the surface
that rolls vigorously over the skin. The tool consists
of 24 circular arrays of eight needles (1,500 mm long)
each (total 192 needles) in a cylindrical assembly.
The needles are made of stainless steel, which is
mechanically strong and nontoxic.
The face was sterilized with povidone-iodine and
alcohol. (Proper wiping of povidone-iodine is ne-
cessary to prevent foreign body granuloma forma-
tion.) Ice packs were used throughout the procedure
to minimize pain. The treatment was then performed
by rolling the needling tool over the areas affected by
acne scars five times in the four directions (vertical,
horizontal, and diagonal) without pressing too hard
(lips and eyelids were avoided). In patients with deep
scars, an assistant stretched the skin perpendicular to
the Dermaroller movement to reach the base of the
scar. The skin bled for 30 seconds to 2 minutes,
which was less than normal clotting time, and wet
gauze swabs were used to soak up any fluid ooze.
Group 2 (100% TCA CROSS)
The skin was cleaned well and degreased with
acetone. Wooden applicators tips were sized to a
dull point approximately the size of the scars and
used to apply 100% TCA. Focal pressing by the
applicator was maintained until an even white
frosting formed in each scar. Topical antibiotic
D E R M AT O L O G I C S U R G E RY2 0 8
T R E AT M E N T O F AT R O P H I C A C N E S C A R S
cream and sunscreen were applied immediately after
the procedure.
After each session, all patients were instructed to
minimize sun exposure, trauma, and tension at the
scar site and to apply sunscreen daily with a sun
protection factor of 50 or more. Patients in group 2
were asked to apply antibiotic cream until focal crust
formation and to avoid disturbing the crusts.
The main outcome measures were overall disease
severity score, global response to treatment, and side
effects. Digital color facial photographs were taken
using a Sony Cyber-shot digital camera (DSC-W50,
TABLE 1. Types of Postacne Atrophic Scars and Overall Score Severity Before and After Treatment
Group 1
(Dermaroller)
Group 2 (Chemical Reconstruction
of Skin Scars Method)
Patient
Types of
Scars
Postacne Scar Score
Patient
Types of
Scars
Postacne Scar Score
Before
Treatment
After
Treatment
Before
Treatment
After
Treatment
1 Ice pick 70 42 1 Rolling,
boxcar,
ice pick
120 60
2 Rolling,
boxcar
60 12 2 Rolling,
boxcar,
ice pick
115 23
3 Rolling,
boxcar
100 20 3 Rolling,
boxcar,
ice pick
100 20
4 Rolling,
boxcar
25 5 4 Rolling,
boxcar
50 11
5 Ice pick,
boxcar
30 8 5 Boxcar 80 24
6 Boxcar 150 35 6 Rolling 50 15
7 Ice pick 120 90 7 Ice pick,
boxcar
80 16
8 Rolling 70 10 8 Ice pick,
boxcar
70 12
9 Ice pick,
boxcar
80 44 9 Ice pick,
boxcar
130 19
10 Rolling 50 13 10 Rolling 30 9
11 Ice pick 100 45 11 Ice pick 90 18
12 Ice pick,
boxcar
90 27 12 Rolling,
ice pick
40 9
13 Rolling,
boxcar
97 9
14 Ice pick,
rolling
30 12
15 Rolling,
boxcar
50 6
Mean7standard
deviation
74.87 35.6 25.27 23.0 79.67 32.8 19.77 13.7
P-value o.001
o.001
Weighted scale: 3 points for deep scars, 2 points for shallow scars, 1 point for superficial scars.
3 7 : 2 : F E B R U A RY 2 0 1 1 2 0 9
L E H E TA E T A L
Sony Corp, Tokyo, Japan). Left and right profile
views were obtained at baseline, during follow-up at
each visit, and at the end of follow-up 4 weeks after
the last session. A blinded observer evaluated clinical
response to treatment for each patient at each visit
(every 4 weeks) and at the end of follow-up (4 weeks
after the last session). The observer used the
following weighted scale (3 points for deep, 2 points
for shallow, 1 point for superficial scars),13 then
global response to treatment was rated using a
quartile grading scale (0, slight improvement,
o25%; 1, moderate improvement, 25–49%; 2,
significant improvement, 50–74%; 3, marked
improvement, � 75%).
Any side effects observed were recorded at each
treatment session and follow-up visit, and pain was
graded on a scale of 0 (none) to 9 (maximum).
Patients were asked to assess their percentage of
improvement using the same quartile grading scale
on a questionnaire completed at the end of the study.
Statistical Analysis
Data were coded and entered using SPSS version 17
(SPSS, Inc., Chicago, IL). Data were summarized
using means7 standard deviations for quantitative
variables and percentages for qualitative variables.
Comparisons between groups were made using
nonparametric tests (e.g., Mann-Whitney and Wil-
coxon signed-rank tests). Correlation was done to
test linear relation between quantitative variables.
pr.05 was considered statistically significant.
Results
This comparative study was conducted on 30
patients, 27 of whom completed the course of
treatment (Figure 1). Fifteen (55.6%) were skin type
III, 11 (40.7%) were skin type IV, and one (3.7%)
was skin type II. Patients in group 1 were aged 20 to
42 (mean 29.77 7.3), whereas those in group 2 were
aged 19 to 36 (mean 23.87 5.8); both groups
included patients with different types of atrophic
postacne scars (Table 1). No statistically significant
difference was found between the groups regarding
overall scar severity before treatment (p = .77).
There was statistically significant improvement in
degree of overall scar severity before and after
treatment for both groups (po.001 for both) (Table
2 and Figure 2), but there was no statistically
significant difference between the groups (p = .98),
indicating that both modalities had comparably
similar net results (Table 3). There was also decline
in the percentage of overall improvement after each
treatment, measured separately, that was slightly
higher in group 2 (mean7 SD 75.379.44 than in
group 1 (mean 68.37 19.3), although this difference
was not statistically significant (p = .51) (Table 2).
Regarding global response, in group 1 (Figures 3 &
4), seven patients (46.7%) showed significant
improvement, five (33.3%) showed moderate im-
provement, two (13.3%) showed mild improvement,
Figure 1. Trial profile of patients included in the study.
TABLE 2. Overall Scar Severity Score and Per-
centage Improvement After Treatment
Mean7Standard Deviation
Group
Scar Severity
Score
Percentage
Improvement
1 25.27 23.0 68.37 19.3
2 19.77 13.7 75.37 9.4
p-value .98 .51
D E R M AT O L O G I C S U R G E RY2 1 0
T R E AT M E N T O F AT R O P H I C A C N E S C A R S
and one (6.7%) showed minimal improvement. In
group 2 (Figures 5 & 6), eight patients (66.7%)
showed significant improvement, three (25%)
showed moderate improvement, and one (8.3%)
showed mild improvement. There was no statisti-
cally significant difference between the groups
(p = .25). Seventy percent of patients reported sub-
jective improvement of their acne scars (range 50–
80%), in agreement with improvement in scar
severity score, and they were satisfied with their
treatment results.
In each patient, before and 4 weeks after the fourth
session, there was a statistically significant greater
mean percentage improvement in rolling scars in
group 1 (87.8%) than in group 2 (66.5%) (po.001)
and showed a statistically significant greater mean
percentage improvement in ice pick scars in group 2
(86.2%) than in group 1 (52.5%) (p = .001). There
was no statistically significant difference in mean
percentage improvement in boxcar scars between the
groups (p = .16) (Table 3).
Side Effects
Although all patients in group 1 received topical
anesthesia for 1 hour before the session, and ice
packs were used throughout the procedure, they
experienced pain during the sessions (mean pain
score 5.47 1.9). Transient erythema and edema
were noted that lasted for a mean of 3.070.8 days,
and overall mean downtime was 3.771.0 days
(Table 4). Two of the patients in group 1 observed a
few new acne lesions, although they had been free of
acne for the last 6 months; they were treated with
combination of topical benzoyl peroxide 5% and
retinoic acid 0.5% for 4 weeks with complete
recovery and then completed their sessions.
In group 2, all patients noted burning pain (mean
pain score 3.87 1.6). Cosmetic discomfort was
noticed in all patients due to the presence of
brownish crusts within 2 days that lasted for 7 to 10
days. Postcrust erythema lasted for a mean of
15.974.3 days. Overall mean downtime was
9.673.1 days (Table 4). Transient postinflamma-
tory hyperpigmentation lasting 2 to 6 months
occurred in six patients (50%; three of whom were
skin type III) in group 2 and was treated with topical
hydroquinone 4%.
Pain scale scores were statistically significantly lower
(p = .03), post-treatment erythema lasted statistically
significantly longer (po.001), and overall downtime
was statistically significantly longer (po.001) in
group 2 than in group 1.
Discussion
To our knowledge, this is the first study comparing
PCI using the Dermaroller with 100% TCA CROSS
in the management of atrophic acne scars. Our
study revealed statistically significant overall
improvement of atrophic acne scars in both groups
of patients (po.001); there was no statistically
significant difference between the groups, indicating
that the procedures gave comparably close results.
This study revealed that PCI (Dermaroller) improved
atrophic acne scars in 100% of patients, with overall
scar improvement of up to 91.7% (mean 68.37
19.3). Our results were consistent with a previously
published study using the collagen induction tech-
nique (CIT).4 Fabbrocini and colleagues4 showed
that the severity of the acne scars in all patients was
greatly reduced after only two sessions with an
8-week interval, without any side effects apart from
redness and swelling, which disappeared in 2 to 3
74.879.58
25.219.67
0
10
20
30
40
50
60
70
80
90
Group 1 Group 2
Before After
Figure 2. Mean scar severity score before and after treat-ment in both groups.
3 7 : 2 : F E B R U A RY 2 0 1 1 2 1 1
L E H E TA E T A L
TA
BLE
3.
Scar
Severi
tyS
co
rean
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erc
en
tag
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pro
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en
tfo
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Acn
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car
Typ
e
Typ
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fS
car
Pati
en
t
Gro
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1
Pati
en
t
Gro
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2
Acn
eS
car
Severi
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core
Perc
en
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e
Imp
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en
t
Acn
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Severi
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Perc
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Imp
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Befo
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atm
en
t
Aft
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Tre
atm
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t
Befo
re
Tre
atm
en
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Aft
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Tre
atm
en
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Ro
llin
g2
33
487.9
145
42
6.7
357
787.7
238
14
63.1
410
190
335
17
51.4
870
10
85.7
428
871.4
10
50
13
74
650
15
70
13
45
393.3
930
776.7
14
10
280
10
30
970
15
20
195
12
19
763.1
Mean7
SD
36.9
722.3
5.1
74.4
86.77
6.9
34.4
79.9
14.97
11.6
59.07
22.0
Bo
xca
r2
27
870.4
125
964
343
13
69.8
239
392.3
415
473.3
333
293.9
515
473.3
422
386.4
6150
35
76.6
580
24
70
936
18
50
726
580.1
12
32
778.1
830
486.7
13
52
688.5
940
10
75
Mean7
SD
46.2
743.8
11.9
710.5
72.57
10.8
36.9
718.6
7.57
7.2
781.07
10.7
Ice
pic
k1
70
42
40
150
982
515
473
238
392.1
7120
90
25
332
196.9
980
44
45
754
11
79.6
11
100
45
55
840
880
12
58
20
65.5
960
296.7
14
20
10
50
11
90
18
80
15
30
583.3
12
21
290.5
Mean7
SD
57.1
737.8
30.5
728.7
53.57
19.7
48.1
721.0
6.77
5.9
87.27
7.6
SD
=st
an
dard
devia
tio
n.
D E R M AT O L O G I C S U R G E RY2 1 2
T R E AT M E N T O F AT R O P H I C A C N E S C A R S
days. After PCI, our patients experienced transient
erythema and edema that lasted for a mean of
3.070.8 days, and overall mean downtime was
3.771.0 days, which was consistent with other
studies.2,4 Imran2 studied the efficacy of PCI through
the Dermaroller in treatment of atrophic facial scars
of varying etiology and reported excellent response
in 72.2% of patients. Fernandes and Signorini14
showed that CIT had advantages over conven-
tional methods. Most important is that the
epidermis remains intact, eliminating most of the
risks of laser resurfacing. Histological examination
in their study showed that the skin became
thicker, with much greater collagen deposition and
significantly more elastin. Aust and colleagues15
also showed considerably greater collagen and
elastin deposition 6 months postoperatively, which
might explain why rolling scars characterized by
Figure 3. A male patient in group 1 (A) before and (B) 4 weeks after four sessions of percutaneous collagen induction.
Figure 4. A female patient in group 1 (A) before and (B) 4 weeks after four sessions of percutaneous collagen induction.
3 7 : 2 : F E B R U A RY 2 0 1 1 2 1 3
L E H E TA E T A L
dermal tethering12 showed better results with the
Dermaroller in our study (a statistically significantly
greater mean percentage improvement in group 1
(87.8%) than in group 2 (66.5%) (po.001).
Major advantages of PCI are that patients had no
open wound and consequently required only a short
healing phase, which is encouraging for many
patients. Because the epidermis and stratum
corneum were never removed, there was no risk
of photosensitivity or any postinflammatory
dyschromia.16 Disadvantages were the surgeon’s
exposure to blood, the need for complete anesthesia
of the skin when performing needling, swelling
and bruising for the first few days, and that the
final result took a long time because new collagen
continues to be laid down for approximately 3
months.15,16
Figure 5. A male patient in group 2 (A) before and (B) 4 weeks after four sessions of 100% chemical reconstruction of skinscars, with no reported side effects.
Figure 6. A male patient in Group 2 (A) before and (B) 4 weeks after four sessions of 100% chemical reconstruction of skinscars, with no reported side effects.
D E R M AT O L O G I C S U R G E RY2 1 4
T R E AT M E N T O F AT R O P H I C A C N E S C A R S
On the other hand, improvement of atrophic acne
scars in our patients receiving CROSS was up to
85.3% (mean 75.379.4). Our results were consis-
tent with those of Lee and colleagues,8 who found a
mean improvement of 68% after three courses of
CROSS. In another study,10 50.5% of patients
showed improvement, with better clinical response
in deep than shallow boxcar scars. Yug and
colleagues11 used 95% TCA CROSS on patients
with ice pick scars and reported high patient
satisfaction. We used 100% TCA to achieve better
clinical improvement because Lee and colleagues8
studied the clinical effects of 65% and 100% TCA
CROSS on atrophic acne scars in dark-complexioned
patients and stated that application of a higher
concentration was more effective with no greater
frequency of complications. The number of CROSS
sessions in our study was four at 4-week intervals,
whereas the study done by Yug and colleagues9 used
six sessions at 6-week intervals. Lee and colleagues8
stated that the clinical improvement was propor-
tional to the number of courses of CROSS. That
study reported mean improvement of 68% after
three courses of CROSS.
In our study, ice pick scars showed a statistically
significantly greater mean percentage of improve-
ment in group 2 (86.2%) than in group 1 (52.5%)
(p = .001). The deep depth of the ice pick type
scars, which cannot be fully reached using the
Dermaroller and should be treated using a focally
concentrated treatment option such as CROSS,
could explain this. This was consistent with the
study of Kim and colleagues,1 a split-face trial in 20
patients with rolling and ice pick acne scars to
compare the efficacy of a 1,550-nm Er:Glass
fractional laser (three times with 6-week intervals)
and CROSS (two times with a 12-week interval) in
the treatment of acne scars. They reported significant
improvement of rolling scars on the side treated with
the laser and stated that there was no statistically
significant difference between the two treatment
sides in ice pick type scars (e.g., CROSS was more
effective treating the ice pick scars than the rolling
type).
In our study, patients treated with CROSS experi-
enced cosmetic discomfort due to the presence of
brownish crusts within 2 days that lasted for 7 to 10
TABLE 4. Side Effects
Pain Scale (0–9) Posterythema, Days Downtime, Days
Patient Group 1 Group 2 Group 1 Group 2 Group 1 Group 2
1 8 3 3 19 3 14
2 7 3 3 21 4 14
3 5 2 2 21 5 9
4 6 1 2 10 3 10
5 4 4 3 11 3 10
6 3 5 4 12 4 7
7 6 5 4 15 4 5
8 7 6 3 18 5 14
9 8 6 3 21 2 10
10 4 5 4 15 2 6
11 3 4 2 18 3 9
12 2 2 3 10 4 7
13 6 4 5
14 5 3 5
15 7 2 3
Mean7 standard
deviation
5.47 1.9 3.87 1.6 3.07 0.8 15.97 4.3 3.77 1.0 9.67 3.1
p-value .03 o.001 o.001
3 7 : 2 : F E B R U A RY 2 0 1 1 2 1 5
L E H E TA E T A L
days and postcrust erythema that lasted for a mean
of 15.974.3 days. The overall mean downtime was
9.673.1 days, transient postinflammatory hyper-
pigmentation occurred in six patients (50%) and
lasted for 2 to 6 months; three of these patients were
skin type IV, and the other three were skin type III.
The patients who experienced this transient postin-
flammatory hyperpigmentation had a history of
excessive exposure to sun without the application of
sunscreen after the procedure. This reported side
effect was consistent with previous studies.8,9
CROSS is an effective and cost-effective treatment of
acne scars on a focally treated area, especially in a
developing country such as ours.
In conclusion, we would recommend PCI over 100%
TCA CROSS for treatment of rolling acne scars,
although considering that this is an invasive
procedure, CROSS is a valuable and effective means
of treating rolling acne scars. We recommend 100%
TCA CROSS over PCI for treatment of boxcar and
ice pick acne scars, although in patients who cannot
tolerate prolonged downtime and need to get back to
a social life as soon as possible, PCI is a valuable
means of treating boxcar and ice pick scars. PCI may
be more suitable for patients with a history of skin
dyschromia because of a higher incidence of
consequent postinflammatory hyper- and hypopig-
mentation with 100% TCA CROSS. A lengthy
follow-up period before further intervention is
recommended because final response usually re-
quires an extended period of time. More than one
session is also recommended because greater im-
provement is achieved after multiple sessions with
both techniques, especially PCI. Combining both
procedures may have an even better response.
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Address correspondence and reprint requests to: Rania M.Abdel Hay, MD, 13th Abrag Osman, kornish El Maadi,Cairo, Egypt (11431), or e-mail: [email protected]
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