Eficacy of a Needling Device for the Treatment of Acne Scars

Copyright 2014 American Medical Association. All rights reserved.

Efficacy of a Needling Device for the Treatment of Acne ScarsA Randomized Clinical TrialMurad Alam, MD, MSCI; Sandra Han, MD; Marisa Pongprutthipan, MD; Wareeporn Disphanurat, MD;Rohit Kakar, MD; Michael Nodzenski, BA; Natalie Pace, BS; Natalie Kim, BS; Simon Yoo, MD; Emir Veledar, PhD;Emily Poon, PhD; Dennis P. West, PhD

IMPORTANCE Neocollagenesis can be achieved using a dermal rolling needle device, therebyreducing the appearance of acne scars.

OBJECTIVE To determine the efficacy of a needling device for treatment of acne scars.

DESIGN, SETTING, AND PARTICIPANTS We performed a single-center, rater-blinded, balanced(1:1), split-face, placebo-controlled, parallel-group randomized clinical trial at an urbanacademic institution. The study took place from November 30, 2009, through July 27, 2010.Twenty healthy adults (age range, 20-65 years) with acne scars on both sides of the face wereenrolled. Fifteen individuals completed the study, and no enrolled participants werewithdrawn for adverse effects.

INTERVENTIONS For each participant, one side of the face was randomized for needling.Three needling treatments were performed at 2-week intervals.

MAIN OUTCOMES AND MEASURES Two blinded dermatologists separately rated participants’acne scars based on standard digital photographs obtained at baseline and at the 3-monthand 6-month follow-up visits on the quantitative global scarring grading system.

RESULTS Mean scar scores were significantly lower in the treatment group compared withbaseline at 6 months (mean difference, 3.4; 95% CI, 0.2-6.5; P = .03) and nominally but notsignificantly lower compared with baseline at 3 months (mean difference, 2.4; 95% CI, −0.01to 4.8; P = .052). In the control group, mean scar scores did not vary significantly frombaseline at 3 months (mean difference, 1.0; 95% CI, −1.4 to 3.4; P = .96) and at 6 months(mean difference, 0.4; 95% CI, −2.3 to 3.5; P > .99). The needling procedure was notparticularly painful, with a mean pain rating of 1.08 of 10. Participants perceived a 41% meanimprovement in overall scar appearance on the treated side. No adverse events werereported.

CONCLUSIONS AND RELEVANCE After 3 needling treatments, there was improvement in theappearance of acne scars over time compared with the control group, with minimal painreported.

TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00974870

JAMA Dermatol. 2014;150(8):844-849. doi:10.1001/jamadermatol.2013.8687Published online June 11, 2014.

Author Affiliations: Department ofDermatology, Feinberg School ofMedicine, Northwestern University,Chicago, Illinois (Alam, Han,Pongprutthipan, Disphanurat, Kakar,Nodzenski, Pace, Kim, Yoo, Poon,West); Department ofOtolaryngology, Feinberg School ofMedicine, Northwestern University,Chicago, Illinois (Alam); Departmentof Surgery, Feinberg School ofMedicine, Northwestern University,Chicago, Illinois (Alam); Departmentof Medicine, Emory University Schoolof Medicine, Atlanta, Georgia(Veledar); Center for Research andGrants, Baptist Health South Florida,Miami (Veledar).

Corresponding Author: Murad Alam,MD, MSCI, Department ofDermatology, Feinberg School ofMedicine, Northwestern University,676 N St Clair St, Ste 1600, Chicago, IL60611 ([email protected]).

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A cne scarring has been associated with significant psy-chological consequences.1 Treatment of acne scarringremains a therapeutic challenge, with treatment ap-

proaches that include a range of possible options. In recentyears, fractional laser resurfacing has been used successfullyto reduce scars associated with acne. Nonablative and abla-tive lasers can be used to either remove or perforate skin in afine pinpoint pattern, with resulting neocollagenesis; only afraction of the skin is treated with each treatment, and a se-ries of treatments are required to treat the entire affectedsurface.2

It has been suggested that neocollagenesis and improve-ment of acne scars can also be achieved using needle rollers,3

which use a mechanical, macroscopic approach to induce smallepidermal and dermal perforations. Needle rollers are cylin-drical objects with a circumferential array of perpendicularlyplaced needles and a rotational axle affixed to a handle. Likepaint rollers, such devices can be moved back and forth alongthe skin.

Needling as a possible treatment for acne scarring was in-troduced by Camirand and Doucet,4 who described use of atattoo gun to abrade acne scars. Fernandes5,6 subsequently as-serted that needling with a roller led to percutaneous colla-gen induction. Aust et al7 retrospectively reported needlingused to treat various skin textural complaints, including scar-ring. In a prospective trial of rolling acne scars, Fabbrocini etal8 reported a benefit in patients treated with needle rollers.We describe the results of a randomized clinical trial to assessthe degree of benefit of needle rollers for treatment of acnescars, including macular, rolling, ice pick, boxcar, and hyper-trophic scars.9,10

MethodsStudy DesignThis study was a single-center, rater-blinded, balanced (1:1),split-face, placebo-controlled, parallel-group randomized clini-cal trial. The study was approved by the Northwestern Uni-versity Institutional Review Board, and written informed con-sent was obtained.

Participant SelectionParticipants were enrolled (N.K.) and data were collected froma university-based urban dermatology clinic, using approvedpostings, from the nearby university community. Inclusion cri-teria were as follows: age of 18 to 70 years, good general health,Global Acne Scarring Classification grades 2 through 4, and atleast two 5 × 5-cm areas of acne scarring on the face (with atleast 3 definable acne scars in each area). Exclusion criteria wereas follows: history of keloids or hypertrophic scars, skin in-fection or active skin disease other than mild acne in or aroundthe study areas, active systemic or local skin disease likely toalter wound healing, treatment within the last 6 months orpending treatment within the subsequent 6 months with in-jectable fillers or ablative or nonablative laser resurfacing tothe study areas, medication with isotretinoin or other oral reti-noids within the past 12 months, current treatment with an-

ticoagulants or antithrombotics, or allergy to topical anesthet-ics (eg, lidocaine and prilocaine).

Study ProceduresAt the screening and baseline visit (week 0), each partici-pant’s medical history was recorded, and baseline standard (ie,anterior and 45° lateral view in a custom device that stabi-lizes the chin and forehead) digital photographs were ob-tained with a digital camera (Powershot G10; Canon). Partici-pants were instructed to stop using any topical peelingmedications and topical vitamin A treatments on their face 1week before treatment and to keep this treatment discontin-ued until at least 4 weeks after their final treatment.

Three treatment visits were performed at 2-week inter-vals (ie, weeks 1, 3, and 5). At each of these visits, needling wasperformed on the study treatment area, and topical anes-thetic was only massaged into the control area. Digital photo-graphs and adverse events (eg, infection, prolonged ery-thema, prolonged edema, serosanguineous drainage, bleeding,ulceration, erosion, and pigmentation), including their dura-tion, resolution, intensity, relationship to the study proce-dure, and any curative actions taken, were recorded before eachtreatment.

At 3 and 6 months after the first treatment, participantsreturned for follow-up visits. Digital photographs of the studyareas were again obtained, any adverse events were re-corded, and a participant satisfaction questionnaire was ad-ministered.

Needling InterventionAt each treatment visit, topical anesthetic (a 5% emulsionpreparation that contained 2.5% each of lidocaine and prilo-caine, AstraZeneca) was applied to the treatment area for 1 hourunder occlusion. After the topical anesthetic was washed off,the skin was cleaned with chlorhexidine and needling treat-ment was administered (MTS Roller, CR10 [1.0 mm] or CR20[2.0 mm]; Clinical Resolution Laboratory). The roller depth wasdetermined by clinical evaluation of skin thickness and scarseverity. Specifically, if scars appeared to be very fine and theparticipant had less sebaceous, fine skin, as was the case insome female participants, then a 1.0-mm device was used; oth-erwise, a 2.0-mm device was used. During each procedure, thedevice was rolled over the skin back and forth in each of 8 lin-ear directions around the midpoint of the study treatment area(eg, north to south and back, northeast to southwest, east towest, southeast to northwest, and so on), such that the treat-ment area was traversed a total of 16 times, end to end. Painlevel was recorded based on a 10-point visual analog scale af-ter the procedure. Immediately after each treatment, gentlemanual pressure with gauze was applied for 5 minutes to con-trol pinpoint bleeding and serum secretion. The skin wassoaked with saline swabs for an hour to facilitate hydrationwhile the individuals were educated regarding the need forhome care. For prophylaxis, participants with a history of her-pes simplex virus were treated with oral antivirals (acyclovir,400 mg 3 times a day for 5 days), and participants with an in-creased risk of bacterial infection as determined by the phy-sician (eg, prior history of inflammatory acne or folliculitis)

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were treated with an oral antibiotic (eg, cephalexin, 1 g 3 timesa day for 5 days). For wound care, a bland emollient (Aqua-phor Healing Ointment [Eucerin]; Beiersdorf Inc) was recom-mended for continual application at least twice daily for 7 days.Participants were instructed to avoid direct sun exposure andthe use of any potentially irritating topical products (eg, gly-colic acid–containing products, scrubs and foams, or topicalretinoids) on their face for 1 week.

After the first treatment visit and before and after all sub-sequent treatment visits, the MTS Roller was cleaned thor-oughly by repeated immersion in glutaraldehyde and/or ethylalcohol. The device was then further cleaned by gas steriliza-tion, stored in a closed package, and labeled with the partici-pant’s name and the first treatment date on the box until thenext treatment. This sterilization process was followed to en-sure a high level of infection control in this research setting.

OutcomesThe primary outcome measure was the quantitative global scar-ring grading system, developed by Goodman and Baron.9 Thissystem assesses scar appearance by counting the number ofmild, moderate, severe, and hyperplastic lesions; an algo-rithm is then used to assign a specific point score based on thetypes and frequencies of the lesions observed, with higherscores indicating more scarring. Two blinded dermatologists(S.H. and M.P.) separately rated participants’ acne scars basedon standard digital photographs obtained at baseline and atthe 3-month and 6-month follow-up visits. Forced agree-ment was used to reconcile ratings.

Given that this was an early pilot trial, we considered it ap-propriate to consider acne scars collectively, not separately, byvarious morphologic subtypes (eg, rolling, boxcar, ice pick, andso on). Therefore, we did not record data pertaining to the dif-ferent types of acne scars, and we did not power our study forsubgroup analysis.

Secondary outcome measures included tolerability ofeach treatment as assessed by participant-reported pain ona visual analog scale. Participant-reported or investigator-

observed adverse events, such as infection, prolonged ery-thema, prolonged edema, serosanguineous drainage, bleed-ing, erosions, ulcerations, hyperpigmentation, andhypopigmentation, were recorded at each treatment visitand at the 3-month follow-up. Participant satisfaction wasassessed with a questionnaire administered at the 6-monthfollow-up.

Sample SizeThe sample size of 20 participants would have had 80% powerto detect an effect size between 2 time points of 0.89, whereeffect size is defined as the mean difference between time pointsdivided by the time point–specific SD.

RandomizationRandomly generated 1’s and 2’s were sealed separately inopaque envelopes (N.K.) and used to assign the leftmost la-beled acne scar area on a given participant to the treatment arm(1) or the control arm (2), with the contralateral side then re-ceiving the remaining assignment.

BlindingGiven that the control arm was easily distinguished by visualand tactile cues from the treatment arm during treatment, par-ticipants and the treating dermatologist (M.A.) were notblinded. The 2 dermatologist raters of photographs (S.H. andM.P.) did not participate in randomization or treatment andtherefore were able to be blinded regarding assignment.

Statistical AnalysisChanges in mean scar scores from baseline to 3 and 6 months,respectively, were computed for the treatment and control arms.Repeated-measures analysis of variance with pairwise com-parisons with Sidak adjustment were performed to test whetherthe scar score varied on treatment type, time, or the interac-tion between the two. Means were also computed for painscores, and repeated-measures analysis of variance was usedto test whether pain scores varied on time. The Wilcoxon signedrank test was used to assess whether the difference in overallacne scar appearance was associated with treatment type.

ResultsThe study took place from November 30, 2009, through July27, 2010. Twenty individuals consented, and 5 dropped out be-fore the first treatment. The remaining 15 completed all treat-ments and are analyzed. The mean age of analyzed partici-pants was 33.7 years (range, 20-65 years), 9 were men, 3 hadreceived prior treatment for acne scars, and Fitzpatrick skintypes ranged from I to V (1 participant had type I, 4 partici-pants had type II, 6 participants had type III, 3 participants hadtype IV, and 1 participant had type V).

Scar scores were lower in the treatment group comparedwith baseline at 3 and 6 months (Figure 1). In the control group,mean scar scores did not vary significantly from baseline at 3months (mean difference, 1.0, 95% CI, −1.4 to 3.4; P = .96) andat 6 months (mean difference, 0.4, 95% CI, −2.8 to 3.5; P > .99).

Figure 1. Graph of Mean Scar Scores

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6

Sca

r S

core

Time

Baseline 3 mo 6 mo

Control

Needling

Mean scar scores were significantly lower at 6 months compared with baselinein the needling group (P = .03) and nominally but not significantly lower at 3months in the needling group (P = .052).

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However, in the needling group, scar scores were signifi-cantly lower at 6 months compared with baseline (mean dif-ference, 3.4, 95% CI, 0.2-6.5; P = .03) (Figure 2). At 3 monthscompared with baseline, the reduction in scar score in the nee-dling group was nonsignificant (mean difference, 2.4, 95% CI,−0.01 to 4.8; P = .052) (Figure 3).

The needling procedure was not particularly painful.The mean pain rating was 1.08 of 10. Pain ratings increasedslightly over time (P = .01), with week 4 pain ratings(mean, 1.75; 95% CI, 0.90-2.60) significantly higher thanweek 2 (mean, 0.78; 95% CI, 0.40-1.20) and week 0(mean, 0.71; 95% CI, 0.40-1.00).

Participants perceived a 41% mean improvement in over-all scar appearance on the treated side. When asked to esti-mate the discomfort experienced during and in the days aftertheir procedure, participants commonly reported no discom-fort. Most participants were very satisfied with their proce-dure, replied yes when asked if they would do this procedureagain to treat additional scars, and said they would recom-mend needling to their friends.

No adverse events were reported. Mild transient ery-thema and edema, which were not classified as adverse eventsand hence not formally tracked, were routinely observed bythe investigator (M.A.) and reported by participants after treat-ments.

DiscussionThis study reveals some improvement in acne scars after a se-ries of 3 treatments of needling. There is a statistically signifi-cant improvement in such scars in the treatment group frombaseline to 6 months and no significant improvement duringthis period in the control group. Pain associated with the treat-ment is mild, ranging from 1 to 2 on a standard 10-point visualanalog scale. Adverse events were not observed.

We believe this is the first randomized clinical trial to as-sess scar outcomes after needling. In addition, unlike priorstudies on acne scars, this study did not limit the types of acnescars assessed but rather included the complete range of dif-ferent acne scar types.

More important, although acne scars are notoriously dif-ficult to rate in a standardized manner, the rating scale usedby the blinded raters in this study incorporated informationabout scar type and number. Mild, moderate, severe, and hy-perplastic scars were included, as were macular, erythema-tous, and pigmented scars; atrophic scars with shallow anddeep bases; punched-out scars; linear scars; and troughed orrolling scars. For each major scar type, the total count was char-acterized by a numerical score. Inherent in the structure of thescale was the possibility that future ratings could be better orworse than past ratings. As such, the scale used differed fromimprovement scales, which only allow for positive changes orlack of change.

Intraoperative pain was very low but increased on the treat-ment side over time. This finding may suggest an inflamma-tory process, which may have been triggered by early treat-ments and increased over time with subsequent closely spaced

treatments to eventually yield the desired clinical result. Dif-ferences in reported pain perception may be associated withparticipant characteristics and the specific pain regimen used.

Because improvement on the treated sides was better at6 months than after 3 months, there is some evidence that nee-dling provides more than a transient benefit for acne scars. Itremains unclear how many treatments would be optimal andto what extent, if any, more than 3 treatments might have re-sulted in greater cumulative benefit.

As with many studies of this type, participant satisfac-tion was high. Participants reported an approximately 40% re-duction in acne scarring on the treated side, with this beingsignificantly higher than the 22% improvement based on mea-surements by blinded dermatologist raters. Participant satis-faction may have been affected by a placebo effect, as well asa desire to please the investigator, optimism, and cognitive dis-sonance associated with the mild discomfort and inconve-nience associated with the treatment.

We found 2 randomized controlled studies of nonabla-tive fractional laser for treatment of acne scars with meth-

Figure 2. Clinical Response in a Representative Male Participant

A

B

Compared with baseline (A), acne scar reduction can be seen at 6 months (B)for the needling side.






ods similar to those of the current study. In a split-facestudy of a nonablative 1540-nm laser, participants were ran-domized to receive either 3-monthly treatments with laseror no treatment.11 On a scar scale from 0 (absent) to 10(worst possible), at 12 weeks after treatment, the meanblinded rater score of the treated sides was 4.5 vs 6.5 for theuntreated sides, and half of the participants judged theirscars to be moderately or significantly improved. In a ran-domized split-face study of a nonablative 1550-nm frac-tional laser vs a 10,600-mm fractional carbon dioxide laserthat entailed one treatment with each laser, clinical assess-ment by blinded raters was measured on a scale of 1 to 4 (1indicating <25% improvement; 2, 26%-50%; 3, 51%-75%; and4, >75%) and patient satisfaction on a word scale (very satis-fied, satisfied, slightly satisfied, and unsatisfied).12 Threemonths after treatment, the mean improvement on thenonablative fractional side was 2.0, and most participantswere slightly satisfied. Although direct comparison of these2 fractional laser studies to the current study is complicatedby differences in the scales used to assess results, in these

studies and the current one, modest to significant improve-ments were detected by both participants and blindedraters.

Limitations of this study included the loss of powerassociated with participant dropouts. It is possible thatmore definitive results may have been obtained regardingchange after treatment at 3 months and overall differencebetween the treatment and control arms had dropouts beenfewer. However, despite this problem, the treatment armwas found to be associated with a significant improvementin scarring at 6 months compared with baseline. In addition,because some participants with finer scars and skinreceived treatment with 1.0-mm rollers, which would havepenetrated less deeply than 2.0-mm rollers, these partici-pants may have benefited to a lesser extent from neocolla-genesis induced by the associated mechanical injury. Hadall participants received treatment with 2.0-mm rollers, it ispossible the mean overall improvement may have beengreater. We would expect that the results seen at the end ofthe study would be due to long-term skin remodeling and

Figure 3. Clinical Response in a Representative Female Participant

A B

C D

Acne scars at baseline (A) and 3 months (B) for the control side. Compared with baseline (C), acne scar reduction can be seen at 3 months (D) for the needling side.

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not transient edema or erythema: the latter could beexpected to resolve in a few days to weeks at the most, andin our study outcomes were assessed at 3 and 6 monthsafter treatment.

ConclusionsNeedling may be a useful therapy for treatment of acne scars.This treatment resembles a macroscopic, nonthermal ver-sion of so-called fractional nonablative laser resurfacing. Po-tential indications for needling may include use as a stand-alone therapy by patients and physicians who either preferneedling or do not have access to laser therapy or adjuvant useas a supplementary treatment in combination with fractional

laser treatments. The latter use may be more practical in theshort term, given the well-established role of fractional laseras an effective modality for acne scar therapy. With regard tosafety, one theoretic advantage of needling compared with frac-tional laser is there is probably a lesser risk of pigmentationchanges in patients with Fitzpatrick skin type III or greater. Cur-rently, the volume of data and studies on the effects of nee-dling for acne scars is far less than that for fractional laser treat-ment. Side-to-side studies of needling and fractionalnonablative laser for acne scarring are entirely lacking, so nostrong assertions can be made regarding their relative ben-efits. Further studies are needed to better understand the di-ameter of needles, as well as the density (eg, surface area) anddepth (eg, depth in millimeters) of needling treatments, thatare optimal for treatment of acne scarring.

ARTICLE INFORMATION

Accepted for Publication: December 12, 2013.

Published Online: June 11, 2014.doi:10.1001/jamadermatol.2013.8687.

Author Contributions: Dr Alam had full access tothe data in the study and takes responsibility for theintegrity of the data and the accuracy of the dataanalysis.Study concept and design: Alam, Pongprutthipan,Kim, West.Acquisition, analysis, or interpretation of data:Alam, Han, Pongprutthipan, Disphanurat, Kakar,Nodzenski, Pace, Kim, Yoo, Veledar, Poon.Drafting of the manuscript: Alam, Pongprutthipan,Kakar.Critical revision of the manuscript for importantintellectual content: Alam, Han, Pongprutthipan,Disphanurat, Nodzenski, Pace, Kim, Yoo, Veledar,Poon, West.Statistical analysis: Veledar.Obtained funding: Alam.Administrative, technical, or material support: Alam,Han, Pongprutthipan, Disphanurat, Kakar,Nodzenski, Pace, Kim, Poon, West.Study supervision: Alam.

Conflict of Interest Disclosures: Dr Alam isemployed at Northwestern University.Northwestern University has a clinical trials unitthat receives grants from corporate andgovernmental entities to perform clinical research.Dr Alam has been a consultant for Amway and LeoPharma, both unrelated to this research. Dr Alamhas been principal investigator on studies funded in

part by Allergan, Medicis, Bioform, and Ulthera. Inall cases, grants and gifts in kind have beenprovided to Northwestern University and not DrAlam directly, and Dr Alam has not received anysalary support from these grants. Dr Alam receivesroyalties of less than $5000 per year from Elsevierfor technical books he has edited.

Funding/Support: This study was supported byDepartmental Research Funds, Department ofDermatology, Northwestern University, Chicago,Illinois (Dr Alam).

Role of the Sponsor: The funding source had a rolein the design and conduct of the study; collection,management, analysis, and interpretation of thedata; the preparation, review, and approval of themanuscript; and the decision to submit themanuscript for publication.

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Eficacy of a Needling Device for the Treatment of Acne Scars