Comparison of Fractional Erbium-Doped 1,550-nm Laser and a Bipolar Fractional Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A Randomized Split-Face Controlled Pilot Study
Phase: NA
Conditions: Acne Scars
Sponsor: Massachusetts General Hospital

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
 
Official  Title:  Comparison  of  Fractional  Erbium-­Doped  1,550-­nm  Laser  
and  a  Bipolar  Fractional  Radiofrequency  Microneedle  Device  for  the  
Treatment  of  Atrophic  Acne  Scars  in  Ethnic  Skin:  A  Randomized  Split-­
Face  Controlled  Pilot  Study   
                 
NCT  number:  NCT03380845  
 
 
     Document  Date:  1/31/2018  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
Detailed Protocol 
1/31/2018  
 
I.  
Background and Significance 
Acne is a highly prevalent disease and post-acne scaring has shown to have detrimental 
effects on a person’s physical, mental, and social well-being.1  Acne scars can be divided in 
general categories of hypertrophic or keloid scars, atrophic scars (icepick, rolling, boxcar), 
and pigmentation alterations (redness, hypo and hyper-pigmentation). This study will focus 
on treatment of moderate to severe grades of atrophic acne scarring. Our aim is to compare 
the efficacy and safety of a erbium-doped 1,550-nm non-ablative fractional laser and a 
bipolar fractional radiofrequency microneedle device for the treatment of atrophic acne scars 
in ethnic skin (Fitzpatrick Skin Phototypes III-VI) by performing a split-face randomized 
controlled trial.  
 
 
Both devices in this study are already FDA approved treatment modalities for acne scarring.  
History of erbium-doped 1,550-nm non-ablative fractional laser (Fraxel® Restore Laser 
System, Solta Medical, Inc., Hayward, CA): 
Non-ablative fractional lasers work via the theory of fractional photothermolysis, which creates 
hundreds to thousands of microscopic thermal zones (MTZs), or columns of thermally injured 
skin, while sparing the surrounding tissue. The pixilated nature of treatment and the functionally 
unimpaired stratum corneum allow for rapid tissue healing and allows for safer treatments of our 
patients.2 Mechanistically, fractional photothermolysis allows controlled amounts of high energy 
to be delivered deep within the dermis resulting in collagenolysis and neocollagenesis, which 
smoothes the textural abnormalities of acne scarring. 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
Multiple published studies have demonstrated that erbium-doped 1,550-nm non-ablative 
fractional laser (“NAFL”) can be successfully utilized in the treatment of all forms of atrophic 
acne scarring – ice-pick, boxcar, and rolling scars – with a very favorable safety profile in all 
skin types, and thus, has been cleared by Food and Drug Administration (FDA) for that 
particular indication.3-6  According to the manufacture manual (reference attached in the 
“Documents and Attachments” section), NAFL is indicated for “use in skin resurfacing 
procedures as well as treatment of acne scars, surgical scars, lentigos (age spots), solar lentigos 
(sun spots), actinic keratosis, and melasma.” 
History of the fractional radiofrequency microneedle device (Fractora; Invasix 
Ltd./InMode MD Ltd., Israel): 
Fractional radiofrequency is not a laser. Instead, these devices use an array of electrodes that 
allows for zones of thermal wounds to be created between areas of unaffected zones, thus 
stimulating dermal remodeling and allowing for a supply of reservoir cells to promote healing.7 
Variations of fractional radiofrequency exist that employ microneedles to deliver electrical 
current to a particular depth within the dermis that decreases damage to the epidermis. These 
fractional radiofrequency microneedle devices provide an alternative to conventional methods of 
acne-scar treatment (such as NAFL). Great interest has been culminating over the recent years 
for the use of such devices in acne scars due to the absence of light scattering and the absence of 
chromophore-specific targets traditionally needed with laser treatments. As melanin is not a 
target, it is felt to have a higher safety profile in darker skin phototypes.8,9  
A recent study investigated the safety and efficacy of a specific bipolar fractional radiofrequency 
microneedle device (Fractora; Invasix Ltd./InMode MD Ltd., Israel) for acne and acne scarring.10 
In this study, Hellman reported on 8 patients with acne scars and noted that all patients 
(regardless of their skin phototypes) had improvement in their active acne and acne scars after 4 
treatments and a 1 month, on average follow-up period. The treatment was well tolerated without 
any side-effects. Skin biopsies from this study showed reduction in scar depth and new collagen 
formation with an increase in elastic fibers and adnexal structures noted. In a follow-up report, 
Hellman11 showed that 4 out of 8 patients who were in the original study returned for a long term 
follow-up from 1 to 2 years, that showed ongoing clinical improvements in these patients. This 
specific bipolar fractional radiofrequency microneedle (“FRM”) device has been FDA-approved 
for acne scars and skin rejuvenation.   
To this date the efficacy and safety of 1,550-nm fractionated photothermolysis system has not 
been compared to a fractional radiofrequency microneedle device for atrophic acne scars in 
ethnic skin in a randomized split-face controlled trial.12 A major advantage of a split-face self-
controlled design would be to minimize any confounding factors. Laser resurfacing has been 
well studied and is widely used in individuals with fair skin - Fitzpatrick skin phototypes (SPT) 
I to II. However, there is a paucity of published studies involving individuals with darker skin 
types (SPT III–VI)—a population that has a higher risk of laser-associated dyspigmentation.  
Thus, we would like to compare these two devices (NAFL vs FRM) in the treatment of acne 
scarring in Fitzpatrick skin phototypes III-VI by performing a split faced randomized trial with 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
three treatments each spaced 4 weeks apart. Photographs will be taken prior to and after each 
treatment as well as after final follow up. Blinded reviewers will perform photographic review to 
evaluate for efficacy and safety. 
II.  
Specific Aims 
 
The hypothesis of this study is that both erbium-doped 1,550-nm non-ablative fractional laser 
and the bipolar fractional radiofrequency microneedle device are equally effective for the 
treatment of atrophic acne scars in ethnic skin (SPT III-VI). However, the bipolar fractional 
radiofrequency microneedle device has less adverse effects than erbium-doped 1,550-nm non-
ablative fractional laser due to the absence of scattering and the absence of chromophore-specific 
targets - predominantly melanin - traditionally needed with laser treatments; hence the fractional 
radiofrequency microneedle device will have a higher safety profile in darker skin types .   
Objective: To compare efficacy and safety of a erbium-doped 1,550-nm non-ablative fractional 
laser and a bipolar fractional radiofrequency microneedle device for the treatment of atrophic 
acne scars in ethnic skin (SPT III-VI) by performing a split-face randomized controlled trial.  
Primary Endpoint: Improvement in acne scarring will be measured by two blinded evaluators 
both by in-person assessments and by photographic review (digital photography will be used 
under standardized conditions). A quartile grading scale (1 = 1% to 25%, 2 =26% to 50%, 3 
=51% to 75%, 4 = >76% improvement) will be used to measure acne scar improvement.  
Exploratory Objective: Comparing side effects of the different lasers. 
Exploratory Endpoint: measure side effects by patient reported adverse events and blinded 
physician assessment of adverse effects on follow up visits 4 weeks after each treatment as well 
as at final follow up 3 months after last treatment. Wound healing will be graded on a 2-point 
scale (0=appropriate, 1=non-appropriate). Parameters, including erythema, edema, blistering, 
crusting, scarring, hypopigmentation, and hyperpigmentation, will be graded on a 4-point scale 
(0  =  absent, 1=  mild, 2  =  moderate, and 3  =  severe). Patients will also be evaluated the intensity 
of pain during each treatment session using a visual analogue scale (0 = absence of pain, 10 = 
most-severe pain). Mild discomfort, erythema, and edema lasting 4-7 days is expected and usual 
side effects for both of these treatment modalities.  Unexpected adverse events may include 
blistering, hypopigmentation, hyperpigmentation, severe discomfort, bleeding, erosions, ulcers, 
scabbing, scarring. 
 
 
III.  
Subject Selection 
 
Inclusion criteria: Men and women with Fitzpatrick skin types III through VI and facial 
acne scarring of grades III-IV (moderate to severe – see grading chart below) will be enrolled. 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Both sides of the participants’ face should have similar amount and severity of acne scarring. 
Participants will be over 18 years old.  
 
Exclusion criteria: Patients have to be overall healthy without a history of keloidal scarring, 
localized or active infection in the treatment region, immunodeficiency disorders, porphyria or 
light sensitivity, and connective tissue disorders. Per PI discretion, any serious medical condition 
that may interfere with the study. In addition, pregnant or nursing women, patients who have 
been taking isotretinoin for a period of 6 months before treatment, and patients who have 
received any cosmetic treatment (lasers, dermabrasion, chemical peels, etc) in the previous 6 
months will be excluded. Also, patients with renal disease and any allergies to Lidocaine, 
Tetracaine, or Valtrex will be excluded. 
 
Recruitment/Participant Identification Process: Patients recruited will mostly be current 
patients of MGH Department of Dermatology. Providers in and outside of our institution 
regularly send patients to be considered for studies and these patients will be pre-screened by 
study personnel (coordinators and investigators). We will send out an email to all current 
dermatologists within the department asking for referrals to this study. If they have patients with 
acne scarring who are interested in participating in this study, they will refer the patients to the 
study by providing the PI and sub-investigator with patient's name and DOB. There will also be a 
flyer about the study available in the MGH Dermatology clinics. The patient's medical record 
will then be reviewed by the PI or sub-investigator in order to determine if patient meets 
inclusion criteria. Possible participants will be called by the PI or sub-investigator to invite them 
to an introductory visit during which they will be given details about the study and their 
eligibility will be determined by the PI. If the patients are interested in participating in the study 
at this visit, they will be asked to sign the consent form.  

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
The subjects may be enrolled among the PI or sub-investigators own patients. In those instances, 
we will avoid the possibility of patients feeling obligated to participate by offering patients the 
opportunity to take home the consent form and call back to speak with Dr. Sandeep Saluja if they 
want further information about the study or wish to participate.  
IV.  
Subject Enrollment 
Informed Consent Procedure: 
Location: MGH Dermatology, Laser and Cosmetic Center at 50 Staniford St, Stuire#250, 
Boston, MA - 02114. This clinic has private patient rooms where consent will be obtained. 
 
Screening visit and Consent Process: For screening, subjects who meet inclusion/exclusion 
criteria will be asked to read and sign the informed consent document. The consent process is 
conducted and completed prior to conducting any study procedures. Typically, a summary of 
the study is presented by the study staff to patients who are interested and appear to be 
eligible for the study. There is no mandatory waiting period, but sometimes patients are 
informed of the study during clinic or over the phone, and an appointment is then scheduled 
in the dermatology clinic to conduct the formal consent process.  
 
During this appointment, which is conducted in the clinic in a private and quiet study clinic 
room, the study staff will present an overview of the study. They are given the Informed 
Consent Form (ICF) and asked to read it. We allow them to read it in private and we remain 
immediately available (outside the door of the clinic room) and ask them to alert us when 
they are finished. We will step in to monitor their progress periodically. The ICF is then 
reviewed with the study staff who will ensure that the patients questions are answered. The PI 
is also available to answer questions. If the patient feels that they have had ample opportunity 
to review the ICF, understand the study, and want to participate, then the ICF is signed and 
dated by both parties.  
 
At any point in the process, if the participant wants more time to consider the study, the ICF, 
or other standard treatment options, that participant is encouraged to take the ICF home to 
discuss with family and/or friends. Patients who sign the informed consent will be enrolled in 
the study.  
  
Once the patient has been consented, patient will be randomly assigned (via coin flip by 
study coordinator) to have one side of their face treated with a non-ablative fractional 1550 nm 
erbium-doped fiber laser (Fraxel® DUAL Laser System, Solta Medical, Inc., Hayward, CA), 
while the other side of the face treated with a fractional radiofrequency microneedle device 
(Fractora; Invasix Ltd./InMode MD Ltd., Israel). All laser treatments were performed by the 
same dermatologist. 
V.  
Study Procedures 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
Screening Visit 
 
. Participants will be screened based on inclusion and exclusion criteria, Fitzpatrick skin type 
will be determined, and full details of study are explained. If participation is desired, patients will 
sign the consent form at this time.  For patients with documented histories of herpes labials (cold 
sores), antiviral prophylaxis (oral valacyclovir 500 mg twice a day for 5 days, starting the day 
before each laser treatment) will be prescribed. All patients will be instructed to apply Lidocaine 
7%, Tetracaine 7% ointment to the entire face one hour prior to treatment.  
Treatment phase 
Week 0: 
§  
Baseline full face photographs taken 
§  
Blinded evaluators will assess the patient’s photographs. To ensure blinded evaluations, 
the same unblinded investigator will perform all the laser treatments, whereas efficacy 
evaluations will be performed by two trained and experienced evaluators who are blinded 
to the treatment assignment. 
§  
Subjects will apply topical anesthetic (Lidocaine 7%/ Tetracaine 7% Ointment) to the 
entire face one hour prior to the procedure. 
§  
Treatment #1 to both sides of the face (entire R and L sides of the face are each treated 
with one of the two study devices based on randomization). The participant will be 
blinded to which side of face receives which laser or device.  
§  
Review post-laser standard-of-care skin care with participants (sun avoidance, sunscreen 
use, moisturizer use) and provide patient with post-procedure hand-out.  
§  
Complete VAS pain assessment (see documents attached) ((0 = absence of pain, 10 = 
most-severe pain) 
§  
Prescription given for oral valacyclovir per protocol 
Week 4: 
§  
Full face photographs taken 
§  
Blinded evaluators will assess the patient’s photographs for any adverse events.  
§  
Review and evaluation of any adverse events from previous session and complete 
assessment of adverse events form (see attached documents) 
§  
Subjects will apply topical anesthetic (Lidocaine 7%/ Tetracaine 7% Ointment) to the 
entire face one hour prior to the procedures. 
§  
Treatment #2 to both sides of the face (entire R and L sides of the face are each treated 
with one of the two study devices based on randomization). The participant will be 
blinded to which side of face receives which laser or device.  
§  
Review post-laser standard-of-care skin care with participants (sun avoidance, sunscreen 
use, moisturizer use) and provide patient with post-procedure hand-out.  

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
§  
Complete VAS pain assessment (see documents attached) ((0 = absence of pain, 10 = 
most-severe pain) 
§  
Prescription given for oral valacyclovir per protocol 
Week 8: 
§  
Full face photographs taken 
§  
Blinded evaluators will assess the patient’s photographs for any adverse events. 
§  
Review and evaluation of any adverse events from previous session and complete 
assessment of adverse events form (see attached documents) 
§  
Subjects will apply topical anesthetic (Lidocaine 7%/ Tetracaine 7% Ointment) to the 
entire face one hour prior to the procedures. 
§  
Treatment #3 to both sides of the face (entire R and L sides of the face are each treated 
with one of the two study devices based on randomization). The participant will be 
blinded to which side of face receives which laser or device. 
§  
Review post-laser standard-of-care skin care with participants (sun avoidance, sunscreen 
use, moisturizer use) and provide patient with post-procedure hand-out.  
§  
Complete VAS pain assessment (see documents attached) ((0 = absence of pain, 10 = 
most-severe pain) 
§  
Prescription given for oral valacyclovir per protocol 
Week 20: 
§  
Full face photographs taken 
§  
Blinded evaluators will assess the patient’s photographs for any adverse events 
§  
Complete physician assessment of improvement of acne scarring (see documents 
attached) by two blinded evaluators.  
§  
Participants fill out final satisfaction survey (see documents attached) 
End of Study  
 
Post Study: There is a chance that acne scarring on one side of your face would significantly 
improve more than the other side (meaning that one laser was much more effective than the 
other). If this happens, the principal investigator (Dr. Sandy Tsao) will talk with you about using 
the laser that you feel worked the best on the other side after the study is over.  If you did choose 
to do additional treatments after the study for balancing out the treatments, you will have to pay 
for these additional treatments ($500 per laser treatment), since this is a cosmetic treatment and 
insurance will not pay for it.  
 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Version  Date:    1/31/2018  
VI.  
Biostatistical Analysis 
Statistical Methods  
 
The two devices will be randomized to the left and right side of the same patient.  To 
compare the devices, a paired sample t-test will be used.  
 
Sample Size Determination 
 
It would be important to know if one device is a whole category better than the other device, 
as a one category difference would be noticeable to the patient, but a smaller difference might 
not be noticeable.  The acne scar improvement scale has 4 categories (0 = <25% 
improvement, 1= 25 to 50%, 2 = 51 to 75%, 3 = >75%).  Assuming the standard deviation is 
one-half of the mean, with means of 1 and 2, to have 90% power to a detect a pairwise 
difference (left and right side of the face) of mean±SD, 1±0.5 vs 2±1, with a correlation of 
r=0.5 between the two sides of face, using an alpha 0.05 two-sided comparison, a sample size 
of n=20 patients is required. 
 
VII.  
Risks and Discomforts 
 
 Risks of the both types of devices used are similar and include redness, swelling, 
hyperpigmentation (temporary darkening of the skin), hypopigmentation (temporary lightening 
of the skin), scarring, crusting, bacterial skin infection, cold sore reactivation, and blistering of 
the skin. Even though topical numbing cream will be applied for one hour prior to treatment, 
participants will likely feel some discomfort or pain during the procedure. 
Valtrex (anti-viral medication for patient with history of herpes labialis/cold sores) taken one day 
prior to procedure for a total of 5 days has the following possible side effects: nausea, headache, 
vomiting, dizziness, abdominal pain, rash.  
There is a chance that acne scarring on one side of the face would show greater improvement 
than the other side (meaning that one laser was more effective than the other).  
We will offer patient care needed to treat any injury that directly results from taking part in this 
research study.  We reserve the right to bill patient’s insurance company or other third parties, if 
appropriate, for the care the patient get for the injury.  We will try to have these costs paid for, 
but the patient may be responsible for some of them.  For example, if the care is billed to 
patient’s insurer, the patient will be responsible for payment of any deductibles and co-payments 
required by the patient’s insurer. 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
Page  10  
Version  Date:    1/31/2018  
 
VIII.  
Potential Benefits 
 
Acne scarring can be disfiguring and can greatly impact one's social interactions and 
psychological wellbeing. This study helps improve our understanding of efficacy and safety of 
two lasers in treatment of acne scarring in darker skin phototypes. Patients will receive these 
FDA approved, treatments at no cost for their acne scarring that is likely to be very effective 
based on current data supporting efficacy of the two devices used in this study. Laser and 
energy-based treatments are the most effective way of minimizing acne scarring, however, such 
treatments are very expensive, this study would provide treatment at no cost to participants.  
Patients who enroll may also feel a sense of contributing to the benefit of others by participating 
in medical research.  
IX.  
Monitoring and Quality Assurance 
Immediate side effects from treatments will be monitored and recorded, such as redness, edema, 
blistering, hyperpigmentation, hypopigmentation, pain. Risks of the both types of lasers/devices 
used are similar and include redness, swelling, hyperpigmentation (temporary darkening of skin), 
hypopigmentation (temporary lightening of skin), scarring, crusting, bacterial skin infection, cold 
sore reactivation, and blistering of the skin.  
Safety of devices used will be monitored with attention to above side effects. Study progress for 
each patient will be recorded at each visit. 
There may be other unforeseeable risks to participants from the laser treatments that are currently 
unknown. Should these risks become known, patients will be informed about such risks, and 
would be given the option to decide whether they want to continue with the study or they would 
like to withdraw. 
Study could be stopped or modified if there are severe or irreversible unforseeable side effects of 
the two laser treatments used. 
The PI will review events and data for each participant on monthly basis during their monthly 
visits. 
The photographs taken during the study may be used in the future for presentations or 
publications by the study doctor. The photos will not be identifiable in presentations or 
publications as we will be masking the eyes in the photographs.  
 
X.  
References 
 
1.   Purvis D, Robinson E, Merry S, Watson P. Acne, anxiety, depression and suicide in teenagers: a 
cross-sectional survey of New Zealand secondary school students. Journal of Paediatrics and 

 
  
Title: Comparison of Fractional Erbium-Doped 1,550-nm laser and a Bipolar Fractional 
Radiofrequency Microneedle Device for the Treatment of Atrophic Acne Scars in Ethnic Skin: A 
Randomized, Split-Face Controlled Pilot Study 
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Child Health 2006;42(12):793–6. 
2.   Manstein D, Herron GS, Sink RK et al. Fractional photothermolysis: a new concept for cutaneous 
remodeling using microscopic patterns of thermal injury. Lasers Surg Med 2004; 34:426–38. 
3.   Alster TS, Tanzi EL, Lazarus M. The use of fractional laser photothermolysis for the treatment of 
atrophic scars. Dermatol Surg 2007;33:295–9.  
4.   Chrastil B, Glaich AS, Goldberg LH, Friedman PM. Second-generation 1,550-nm fractional 
photothermolysis for the treatment of acne scars. Dermatol Surg 2008;34(10):1327-32. 
5.   Mahmoud B, Srivastava D, Janiga J, Yang J, Lim HW, Ozog D. Safety and efficacy of erbium-
doped yttrium aluminum garnet fractionated laser for treatment of acne scars in type IV to VI 
skin. Dermatol Surg 2010;36(5): 602–609. 
6.   Alexis AF, Coley MK, Nijhawan RI, Luke JD, et al. Nonablative fractional laser resurfacing in 
the treatment of acne scarring in patients with fitzpatrick skin phototypes IV-VI. Dermatol Surg 
2016;42(3):392-402. 
7.   Hruza G, Taub AF, Collier SL, et al. Skin rejuvenation and wrinkle reduction using a fractional 
radiofrequency system. J Drugs Dermatol. 2009;8(30:259-265. 
8.   Chandrashekar, B.S., Sriram, R., Mysore, R., et al. Evaluation of Microneedling Fractional 
Radiofrequency Device for Treatment of Acne Scars. Journal of Cutaneous and Aesthetic 
Surgery. 2014;7:93-97.  
9.   Chae WS, Seong JY, Jung HN, Kong SH, Kim MH, Suh HS, et al. Comparative study on efficacy 
and safety of 1550 nm Er: Glass fractional laser and fractional radiofrequency microneedle device 
for facial atrophic acne scar. Journal of Cosmetic Dermatology 2015;14(2):100–6. 
10.  Hellman J. Retrosceptive study of the use of a fractional radiofrequency ablative device in the 
treatment of acne vulgaris and related acne scars. J Cosmet Dermatol Sci App. 2015;5(4):311-
316. 
11.  Hellman J. Long-term follow-up results of a fractional radiofrequency ablative treatment of acne 
vulgaris and related acne scars. J Cosmet Dermatol Sci App. 2016;6(3):100-104. 
12.  Abdel Hay R, Shalaby K, Zaher H, et al. Interventions for acne scars. Cochrane Database Syst 
Rev. 2016 Apr 2016, Issue 4. Art. No.: CD011946.