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A multicenter clini-cal evaluation of the treatment of mild to moderate inflammatory acne vulgaris of the face with visible blue light in comparison to topical 1% clindamycin antibiotic

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20 Lee WL, Shalita AR, Poh-Fitzpatrick MB Comparative

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21 Ashkenazi H, Malik Z, Harth Y et al Eradication of

Propionibacterium acnes by its endogenic porphyrins after illumination with high intensity blue light FEMS Immunol Med Microbiol 2003;35:17–24.

22 Kjeldstad B, Johnsson A An action spectrum for blue and

near ultraviolet inactivation of Propionibacterium acnes;

with emphasis on a possible porphyrin photosensitization.

Photochem Photobiol 1986;43:67–70.

23 Kjeldstad B Photoinactivation of Propionibacterium acnes

by near-ultraviolet light Z Naturforsch [C] 1984;

39:300–302.

24 Melo TB Uptake of protoporphyrin and violet light

pho-todestruction of Propionibacterium acnes Z Naturforsch [C] 1987;42:123–8.

25 Elman M, Lebzelter J Light therapy in the treatment of

acne vulgaris Dermatol Surg 2004;30:139–46.

26 Charakida A, Seaton ED, Charakida M et al Phototherapy

in the treatment of acne vulgaris: What is its role? Am J Clin Dermatol 2004;5:211–16.

27 Mills OH, Porte M, Kligman AM Enhancement of

comedogenic substances by UV radiation Br J Dermatol 1978;98:145–50.

28 van Weelden H, de Gruihl FR, van der Putte SC et al.The

carcinogenic risks of modern tanning equipment: is UV-A safer than UV-B? Arch Dermatol Res 1988;280:300–307.

29 Kawada A,Aragane Y, Kameyama H et al.Acne

photother-apy with a high-intensity, enhanced, narrow-band, blue light source: an open study and in vitro investigation.

J Dermatol Sci 2002;30:129–135.

30 Omi T, Bjerring P, Sato S et al 420 nm intense continuous

light therapy for acne J Cosmet Laser Ther 2004;6:156–162.

31 Shalita AR, Harth Y, Elman M et al Acne phototherapy

using U.V.-free high intensity narrow band blue light: 3 centres clinical study Proc SPIE 2001;4244:61–73.

32 Elman M, Slatkine M, Harth Y.The effective treatment of

acne vulgaris by a high-intensity, narrow band 405–420 nm light source J Cosmetic & Laser Ther 2003;5:111–117.

33 Tzung TY,Wu KH, Huang ML Blue light phototherapy in

the treatment of acne Photodermatol Photoimmunol Photomed 2004;20:266–69.

34 Gold MH, Rao J, Goldman MP et al A multicenter

clini-cal evaluation of the treatment of mild to moderate inflammatory acne vulgaris of the face with visible blue light in comparison to topical 1% clindamycin antibiotic solution J Drugs Dermatol 2005;4:64–70.

35 Sigurdsson V, Knults AC, van Weelden H Phototherapy of

acne vulgaris with visible light Dermatology 1997;194:

38 Edwards C, Hill S, Anstey A A safe and effective yellow light-emitting diode treatment for mild to moderate acne: A within-patient half-face dose ranging study Abstract J Am Acad Dermatol AB15; March 2006.

39 Gupta A Efficacy and safety of intense pulsed light apy using wavelengths of 400–700 nm and 870–1200 nm for acne vulgaris J Am Acad Dermatol AB27, March 2006.

ther-40 Elman M, Lebzelter J Evaluating pulsed light and heat energy in acne clearance Radiancy White paper, June

2002 Retrieved from http://www.radiancy.com/USA/ appdocs.htm.

41 Herd RM, Dover JS, Arndt KA Basic laser principles Dermatol Clinic 1997;15:355–72.

42 International Union of Pure and Applied Chemistry Compendium of Chemical Terminology 2nd edition,

1997 Retrieved from book/A00446.pdf.

http://www.iupac.org/gold-43 Elman M, Lask G.The role of pulsed light and heat energy (LHE) in acne clearance J Cosmet Laser Ther 2004;6: 91–95.

44 Gregory AN,Thornfeldt CR, Leibowitz KR et al A study

on the use of a novel light and heat energy system to treat acne vulgaris Cosmet Dermatol 2004;17:287–300.

45 Baugh, WP and Kucaba WD Nonablative phototherapy for acne vulgaris using the KTP 532 nm Laser Dermatol Surg 2005;31:1290–6.

46 Bowes LE, Manstein D, Anderson RR Effects of 532 nm KTP laser exposure on acne and sebaceous glands Lasers Surg Med 2003;18:S6–S7.

47 Lee CMW Aura 532nm laser for acne vulgaris – a 3 year experience, Annual Combined Meeting of the American Society for Dermatologic Surgery and the American Society for Mohs Micrographic Surgery and Cutaneous Oncology, New Orleans, LA, October 2003.

48 Seaton ED, Charakida A, Mouser PE et al Pulsed-dye laser treatment for inflammatory acne vulgaris: ran- domised controlled trial Lancet 2003;362:1347–52.

49 Orringer J, Kang S, Hamilton T et al Treatment of acne vulgaris with a pulsed dye laser: a randomized controlled trial.JAMA 2004;291:2834–9.

50 Chu A Pulsed dye laser treatment of acne vulgaris JAMA 2004;292:1430.

51 Alam M, Peterson SR, Silapunt S et al Comparison of the 1450nm diode laser for the treatment of facial acne: a left-right randomized trial of the efficacy and adverse effects Lasers Surg Med 2003;32:S30.

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52 Ortiz A, Van Vilet M, Lask GP,Yamauchi PS A review of

laser and light sources in the treatment of acne vulgaris.

J Cosmetic and Laser Therapy 2005;7:69–75.

53 Ashkenazi H, Malik Z, Harth Y et al Eradication of

Propionibacterium acnes by its endogenic porphyrins after illumination with high-intensity blue light FEMS Immunol Med Microbiol 2003;35:17–24.

54 Gold MH, Bradshaw VL, Boring MM et al The use of a

novel intense pulsed light and heat source and ALA-PDT

in the treatment of moderate to severe inflammatory acne vulgaris J Drugs Dermatol 3(6 Suppl):S15–9, 2004 Nov-Dec.

55 Hongcharu W, Taylor CR, Change Y et al Topical

ALA-photodynamic therapy for the treatment of acne vulgaris.

J Invest Dermatol 2000;115:183–92.

56 Itoh Y, Ninomiya Y, Tajima S et al Photodynamic therapy

for acne vulgaris with topical 5-aminolevulinic acid Arch Dermatol 2000;136:1093–1095.

57 Itoh Y, Ninomiya Y, Tajima S et al Photodynamic therapy

for acne vulgaris with topical delta-amenolevulinic acid and incoherent light in Japanese patients Br J Dermatol 2001;144:575–579.

58 Goldman MP Using 5-aminolevulinic acid to treat acne

and sebaceous hyperplasia Cosmet Dermatol 2003;16:

57–58.

59 Gold MH, Bradshaw VL, Boring MM et al The use of a

novel intense pulsed light and heat source and ALA-PDT

in the treatment of moderate to severe inflammatory acne vulgaris J Drugs Dermatol 2004;3:S15–S19.

60 Pollock B,Turner D, Stringer MR et al.Topical

amenole-vulinic acid-photodynamic therapy for the treatment of acne vulgaris: a study of clinical efficacy and mechanism

of action Br J Dermatol 2004;151:616–22.

61 Kimura M, Itoh Y, Tokuoka Y et al Delta-aminolevulinic

acid-based photodynamic therapy for acne on the body.

J Dermatol 2004;31:956–60.

62 Hwang EJ and Seo K Topical photodynamic therapy for

treatment of acne vulgairs: comparison of two IPL cators and different application times of ALA Abstract

appli-290 American Society for Laser Medicine and Surgery Abstracts pg 86.

63 Alexiades-Armenakas, M Long-pulsed dye laser-mediated

photodynamic therapy combined with topical therapy for mild to severe comedonal, inflammatory, or cystic acne.

J of Drugs in Dermatol 5(1); 2006 January 45–55.

64 Parrish JA New concepts in therapeutic photomedicine:

Photochemistry, optical targetings, and the therapeutic windown J Invest Dermatol 1981;77:44–50.

65 Tuchin VV, Genina EA, Bashkatov AN, et al A pilot study

of ICG laser therapy of acne vulgaris: photodynamic and photothermolysis treatment Lasers Surg Med 2003;33:

296–310.

66 Genina EA, Bashkatov AN, Simonenko GV, et al intensity indocyanine-green laser phototherapy of acne vulgaris: pilot study J Biomed Opt 2004;9:828–34.

Low-67 Lloyd JR and Mirko M Selective photothermolysis of the sebaceous glands for acne treatment Lasers Surg Med 2002;31:115–20.

68 Paithankar DY, Ross EV, Saleh BA, et al Acne treatment with a 1,450nm wavelength laser and cryogen spray cool- ing Lasers Surg Med 2002;31:106–114.

69 Mazer JM.Treatment of facial acne with a 1450 nm diode laser: a comparative study Lasers Surg Med 2004:34: S67.

70 Mazer JM and Fayard V Eighteen months results after treatment of facial acne with the 1450 nm diode laser Abstract 103 American Society for Laser Medicine and Surgery.

71 Santhanam A, Shah A and Kumar P The 1450-nm diode laser in the treatment of inflammatory facial acne vulgaris

in Indian patients – A pilot study J Am Acad Dermatol Abstract P45.

72 Jih MH, Friedman PM, Goldberg LH et al.The 1450-nm diode laser for facial inflammatory acne vulgaris: dose- response and 12-month follow-up study J Am Acad Dermatol 2006;55:80–7.

73 Bernstein EF Lower-energy double-pass 1450 nm laser treatment of acne dramatically decreases discomfort with similar efficacy as compared to standard high-energy treatment Abstract 104 American Society for Laser Medicine and Surgery Abstracts.

74 Friedman PM, Jih MH, Kimyai-Asadi A, et al.Treatment of inflammatory facial acne vulgaris with the 1450 nm diode laser: a pilot study Dermatol Surg 2004;30:147–51.

75 Astner S, Anderson R and Tsao S.

76 Glaich A, Friedman P, Jih M, et al Treatment of matory facial acne vulgaris with combination 595-nm pulsed-dye laser with dynamic-cooling-device and 1450-

inflam-nm diode laser Lasers Surg Med 2005;Epub May 2005.

77 Wang SQ, Counter JT, Flor Me and Zelickson BD Treatment of inflammatory facial acne with the 1,450 nm diode laser alone versus microdermabrasion pluse the 1,450 nm laser: a randomized, split-face trial Dermatol Surg 2006;32:249–55.

78 Lupton JR,William CM, Alster TS Nonablative laser skin resurfacing using a 1540nm erbium glass laser: a clinical and histologic analysis Dermatol Surg 2002;28:833–5.

79 Fournier N,Dahan S, Barneon G, et al Nonablative remodeling: clinical, histologic, ultrasound imaging, and profilometric evaluation of a 1540 nm Er:glass laser Dermatol Surg 2001;27:799–806.

80 Boineau D, Angel S, Nicole A, et al Treatment of active acne with an Er:glass (1.54 um) laser Lasers Surg Med 2004;34:S55.

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81 Kassir M, Newton D, Maris M et al Er:glass (1.54 um)

laser for the treatment of facial acne vulgaris Lasers Surg Med 2004;34:S65.

82 Angel S, Boineau D, Dahan S, Mordon S Treatment of

active acne with an Er:Glass (1.54 um) laser: A 2-year follow-up study Journal of Cosmetic and Laser Therapy 2006;8:171–6.

83 Ruiz-Esparza J, Gomez JB Nonablative radiofrequency

for active acne vulgaris: the use of deep dermal heat in the

treatment of moderate to severe active acne vulgaris (thermotherapy): a report of 22 patients Dermatol Surg 2003;29:333–9.

84 Avram, DK and Fitzpatric RE Treatment of active acne and acne scars with SmoothBeam (1,450 nm) and Thermage (radio frequency): A comparative study ASLMS abstracts 56.

85 Retrieved from http://www.myzeno.com.

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Optimal treatment of acne scarring is prevention of

the same by aggressive treatment of active acne.1,2

Failing that, the treatment of acne scarring may require

the sequential application of several corrective

proce-dures Even so, the degree of improvement is

typi-cally incomplete, as scar can be concealed but not

removed

DEFINITION AND CLASSIFICATION

OF ACNE SCARS

Before appropriate therapies can be selected, acne

scar-ring needs to be qualitatively and quantitatively assessed.3,4

The simplest operational definition of acne scar is a

visi-ble textural abnormality that was historically preceded

by active acne at the same site, and if biopsied, would

reveal histological evidence of a scar In practice, it may

be difficult to confidently assert the provenance of a

particular scar, since the active process – acne or

some-thing else – leading to its creation may be temporally

remote.Yet there are typical configurations of scarring

that are usually believed, based on visual inspection

alone, to be highly likely to have been caused by acne

Acne scars can be classified based on shape and

depth One recently proposed classification recognizes

three types of scars (Fig 8.1):4

• ice-pick scars are V-shaped nicks with a pinpoint

base that may culminate in the shallow papillarydermis or in the deep reticular dermis

• boxcar scars are rectangular scars with vertical

walls and a flat base, and these may also be shallow

or deep

• rolling scars are gently undulating scars that ble hills and valleys, are less well-demarcated, andtend to be less focally deep

resem-Alternatively, acne scars can be considered trophic, atrophic, or a combination thereof:3,5

hyper-• grade 1 acne scarring is distinguished by tous, hypopigmented, or hyperpigmented macules(Fig 8.2)

erythema-• grade 2 is distinguished by mild atrophy or phy, similar to the rolling scars described previously

hypertro-• grade 3 is distinguished by moderate hypertrophy

or atrophy that is visible at social distances of 50 cm

or greater, and rolling and shallow box car scars, aswell as moderate hypertrophic and keloidal scars

• grade 4 is distinguished by severe atrophy or trophy that cannot be flattened by stretching theskin between thumb and forefinger

hyper-8 Treatment of acne scarring

Murad Alam and Greg Goodman

Fig 8.1 Stylized cross-sectional view of ice-pick, rolling,shallow boxcar, and deep boxcar scars (from left to right).Theupper horizontal dashed line denotes the normal depth ofablation with resurfacing procedures, the three lines in apyramidal array represent fibrous bands securing the rollingscar to the dermal–subcutaneous junction (Based on the acneclassification popularized by Jacob, Dover, and Kaminer.)

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The classification of acne scarring as a function of

indi-vidual skin type is less well described It is known that

some individuals are more prone to develop scarring

following resolution of acne papulopustules or cysts,

whereas others may only have transient erosions

or discoloration that eventually remits In general,

patients who have previously developed acne scarring

remain at risk for further scarring following active

acne in the future Acne scarring of equivalent depth

and type may also be more noticeable on patients with

darker skin types or pigmentary abnormality For

instance, the light and shadow of darker skin may

accentuate the apparent depressions associated with

acne scarring; similarly, rosacea or centrofacial redness

may demarcate and define the borders of acne scars on

the cheeks

AGE OF ACNE SCARS AND

ACTIVE ACNE

To some extent, the appropriate treatment for acne

scars is predicated on their age Specifically, if scars are

red, a series of laser treatments with pulsed-dye laser

or intense pulsed light may be especially useful for

reducing this blush if the scars are not more than a fewyears old.6,7 In cases when active acne has resolvedduring the past 6–12 months, caution should be exer-cised when approaching the treatment of scarring It ispossible that the superficial resolution of acne may not

be indicative of a cessation of the deep process, andinvasive procedures such as subcision or resurfacingmay restimulate cyst formation

It is essential to adequately treat and inactivate allongoing acne before treatment on any scarring cancommence The presence of active acne strongly mili-tates against the treatment of any coexisting acnescars.These acne scars may either not be mature – andhence may be susceptible to exacerbation or inflam-mation – or mature themselves but their treatmentmay trigger nearby active acne An in-depth consulta-tion with the patient is required to convey this con-cern It should be explained that the deferment of acnescar treatment does not indicate reluctance to treatacne scars or lack of expertise in such treatment;rather, the postponement is necessary because imme-diate treatment may worsen the combined adversevisual effect and symptomatology of the active acneand acne scarring Active acne cysts may enlarge anddrain, or become painful, and the active acne inflamed

by manipulation may lead to further acne scarring

A final caveat entails the treatment of acne scarring

in patients with pre-existing conditions that may lead

to poor scar healing Such conditions may be managedlike acne scarring in the context of active acne: treat-ment of the scars may be delayed or embarked uponvery gingerly so as to preclude inadvertent exacerba-tion Most authorities suggest that invasive proceduresfor acne scarring be undertaken only 1 year after com-pletion of oral isotretinoin treatment for resistant cys-tic acne A complete history should elicit informationabout such treatment; the timing, type and degree ofsuccess associated with prior acne scarring improve-ment procedures; any tendency to produce keloids orhypertrophic scars after surgery or injury; any ten-dency to hyperpigment after injury; disorders, such ascollagen vascular diseases, that impede wound healing;bleeding diatheses; disorders that predispose to infec-tion; recurrent cold sores; allergies to antibiotics andmedications; and psychological disorders, includingdepression, anxiety, factitial disorders (e.g., compulsiveFig 8.2 Postinflammatory hyperpigmented macules of the

cheek after resolution of active acne

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picking, self-mutilation, etc.) and medication for these.

Picking behaviors are exceedingly common, especially

in young women who have an obsessive need to ensure

the perfection of their skin, and a consequent urge to

extirpate pimples and textural abnormalities with their

nails and other implements.The physician should

care-fully explain that picking after procedures to reduce

acne scarring will worsen this scarring and be highly

counterproductive If the patient seems unable or

unwilling to grasp this concept, or appears unlikely to

to adhere to a postoperative regimen, expert

consulta-tion with a psychologist or psychiatrist is desirable

prior to proceeding with surgery

PATHOGENESIS OF ACNE SCARRING

The pathogenesis of acne scarring is too complex an

issue to discuss fully here, but recent research indicates

that intensity of scarring may be associated with the

extent of inflammation associated with active acne

Specifically, the type and timing of the cell-mediated

immune response may be associated with the degree of

post-acne scarring.8In one study, the cellular infiltrate

and nonspecific immune response were initially greater

but later reduced in patients who did not subsequently

develop scars However, in patients who did develop

post-acne scarring, the initially smaller specific immune

response later increased

MANAGEMENT OF ACTIVE ACNE

If the patient does have active acne, a brief discussion

about treatment of acne scars should be followed by

implementation of a plan to stop the production of

new acne lesions Treatment of active acne can take

12–18 months or more before a steady state of

near-clearance is reached If prior measures to control

active acne have included the use of isotretinoin, a

minimum of 12 months and as much as 18 months

should elapse prior to treatment of acne scarring

Once patients understand that treatment of active acne

is a necessary prerequisite for treatment of acne

scar-ring, they may be more compliant with acne treatment

than in the past

Lack of new acne lesions for a few weeks or 1–2months does not necessarily presage a remission ofactive acne.This may simply be a cyclical or fortuitousreduction in acne that may not persist If some degree

of active acne remains persistent, continuing efforts tomanage this should continue even as invasive treat-ments for acne scarring are commenced Sometimespatients will continue to develop one or two smallpapules every few weeks even when on maximal ther-apy for acne At some point, after treatment with topi-cal and oral antibiotics and retinoids, the surgeon mayhave to decide to proceed with acne scarring treat-ment despite the occasional occurrence of active acne

TYPES OF TREATMENTS FOR ACNE SCARRING: RESURFACING,

NONABLATIVE THERAPY, INCISIONAL SURGERY, INJECTION, CYTOTOXIC THERAPIES

The number and range of treatments for acne scarring

is vast Indeed, the options are so plentiful that evenexperienced practitioners need to group and classifytherapeutic options to simplify decision-making Onegrouping recognizes four major categories:

• treatments for altering the color of the acne mark

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in near-total resolution of scarring, a series of

treat-ments that work synergistically should be selected

Some procedures are more risky and may be

associ-ated with delayed healing, and the practitioner should

determine the level of risk preferred by the patient In

sum, for best outcomes, it is preferable to be (1)

expert at a few procedures rather than to be passably

familiar with a large number and (2) collaboratively

with the patient, develop a rational, sequential

treat-ment plan that cumulatively provides the best possible

outcome

‘Resurfacing’ denotes treatments that entail removal

or destruction of the epidermis and partial-thickness

dermis Subsequent to resurfacing procedures, dermal

and epidermal re-epithelialization occurs, usually over

a period of 1–2 weeks Post treatment, there is a

reduc-tion in acne scars that occurred in the skin strata that

were resurfaced Resurfacing is associated with risk of

hypopigmentation and scar, which can occur if the

depth of ablation reaches the bulge region of the hair

follicle Common resurfacing procedures can rely on

thermal, chemical, or mechanical injury, and include

laser ablation, medium to deep chemical peels,

dermabrasion, and plasma resurfacing

‘Nonablative’ therapies are those that do not fully

de-epithelialize the epidermis and dermis but rather deliver

subdestructive energies that induce skin remodeling

Most commonly, nonablative therapies induce thermal

injury by application of a range of laser and light sources,

but other energy devices, such as bipolar and

mono-polar radiofrequency (RF), may be used

Between resurfacing and nonablative therapies are

an intermediate set of treatments referred to as

‘par-tially ablative’ or ‘minimally ablative’ Typically, these

create a penetrating epidermal and dermal injury only

over a small percentage of the treated skin surface

area Downtime is consequently reduced over that of

resurfacing, but efficacy may be better than for

non-ablative treatments Common examples of partially

ablative therapies are fractional resurfacing as well

as skin needling and rolling

‘Incisional surgery’ entails cutting into the skin, and

may also include removal of skin, or excision Pitting

or ‘ice-pick’ scarring can be treated by punch excision,

punch grafting, or punch elevation Rolling scarring

can be improved by subcision: minute cuts in the skin

followed by abrasion of the underside of the dermis

Large, mixed acne scarring in a linear array can beremoved by standard elliptical excision

In some cases, the skin may be pierced but not cut aspre-packaged injectable fillers or autologous fillers areinstilled under acne scars to raise them flush to theskin ‘Injection’ therapy for acne scars has advancedsince the introduction of a range of new soft-tissueaugmentation materials over the past decade Suchmaterials include autologous fat, human collagen,hyaluronic acid derivatives, calcium hydroxyapatite,silicone, and other agents

Cytotoxic therapies may be most relevant for trophic acne scars Either medical or radiation thera-pies may be used to mitigate the growth of exuberantscars on the chest, face, and back Intralesional agentssuch as 5-fluorouracil (5-Fu), bleomycin, and verapamil,topical agents such as imiquimod, as well as radiationtreatment may help flatten scars

hyper-ACNE SCAR TREATMENT BY RESURFACING

Resurfacing is commonly accomplished by laser, cal application, or dermabrasion To some extent, thechoice of procedure is a function of the age of thetreating dermatologist, and prevailing fashions when

chemi-he or schemi-he trained

Laser resurfacing remains a gold standard for safety

in ablative resurfacing In this procedure, a carbondioxide (CO2), erbium : yttrium aluminum garnet (Er:YAG), or hybrid laser device is used to vaporize theepidermis and partial-thickness dermis.As a calibratedlaser is used, tissue removal is precise, reproducible,and minimally operator-dependent; especially when acomputerized pattern generator (CPG) is used, evenand consistent skin removal is achieved.The CO2laserprovides the deepest injury, some immediate tissuecontraction, hemostasis through its cauterizing effect,and the overall best clinical effect achievable by laser,but downtime with multiple-pass resurfacing can be1–2 weeks The Er:YAG laser is associated with lessinvasive ablation that is more suited to the treatment offine acne scarring or photoaging, but downtime untilcomplete re-epithelialization can be half as long Sinceintraoperative bleeding can complicate and hencelimit multiple-pass Er:YAG laser resurfacing, some

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hybrid devices include a small CO2laser to facilitate

coagulation; alternatively, a low-power and

high-power Er:YAG laser can be paired in the same box for

this purpose Hybrid devices may also provide a

clini-cal effect intermediate between classic Er:YAG and

CO2 laser resurfacing Using an Er:YAG laser after

CO2laser resurfacing can remove a thin layer of debris

and devitalized tissue, and speed healing Notably,

post-treatment erythema after CO2laser resurfacing

can last 2–3 months, although it can be concealed with

make-up Outcome data indicate that most patients are

very pleased with the outcome of their laser

resurfac-ing procedure at 3 months post treatment, and remain

so at 18 months; in the immediate postoperative

period, the anxiety associated with wound-healing

and temporary disfigurement causes mild, transient

concern in some.9

In dermabrasion, the skin is smoothened by

mechani-cal abrasion analogous to sanding The skin is scraped

away with a wire brush or a spinning disk-like burr

covered with diamond particles; in some cases, true

medium- or fine-grit sandpaper that has been

auto-claved and wrapped around the finger or instrument

like a thimble may be used to treat small areas

Dermabrasion has become less popular since the advent

of HIV and other bloodborne infectious diseases that

can be spread by aerosolized particles of skin and blood

Unlike laser resurfacing, dermabrasion is more

opera-tor-dependent, as the pressure applied can modify the

depth of treatment.Acquiring and maintaining adequate

anesthesia during dermabrasion can be challenging, and

certain areas, including the eyelids, nose, malar

promi-nence, and jawline, can be difficult to treat.There are no

controlled studies comparing laser resurfacing with

der-mabrasion for acne scarring, but in the anecdotal

expe-rience of the authors, laser resurfacing appears to be

more consistently efficacious Dermabrasion may,

how-ever, be less prone to cause post-treatment erythema

than laser resurfacing Hypopigmented macules

associ-ated with acne scars (Fig 8.3) have in some cases been

reported to be improved following needle

dermabra-sion (using a tattoo gun without pigment) or focal

manual dermabrasion.10,11

Medium and deep chemical peels are another

resur-facing technique Medium-depth peels typically consist

of sponge application of trichloroacetic acid (TCA),

20–35%, after degreasing of the skin; sometimes, a

prepeel with Jessner’s solution may be performed toimprove even peel penetration Depending on theduration of application and the number of layers ofsolution, a deeper or shallower effect can be achieved.The benefits of medium-depth peeling are that noexpensive machinery, such as a laser, is required Also,there is no aerosolization of infectious particles At thesame time, peels are relatively operator-dependent,and pooling of solution in facial crevices can result inuneven treatment from less experienced practitioners

In general, medium-depth peels provide a shallowerablation than CO2laser resurfacing Deep chemicalpeels, most notably the Baker–Gordon or phenol peel,are deeper-penetrating but carry two potential risks:(1) the potential cardiotoxicity of phenol requiresintraoperative monitoring during full-face peeling;and (2) porcelain-white hypopigmentation will occurafter treatment For patients with focal acne scarringwho always wear make-up, deep peels may be a safeoption due to the small surface area treated and theability to conceal depigmentation post-operatively Aspecial localized case occurs when a toothpick, or thesharp wooden end of a cotton-tip applicator createdafter the applicator has been deliberately broken, isdipped in a very concentrated solution of 95% or100% TCA and then applied to the base of an ice-pick scar This resurfaces the pinpoint base of thescar, and permits repair by granulation, which can fill

in the scar.12Fig 8.3 Hypopigmented cheek scars that are slightlyatrophic

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A more recent variant of resurfacing is plasma

resur-facing.This uses the ‘fourth state of matter’ to precisely

injure epidermis and underlying dermis without

induc-ing immediate sloughinduc-ing of the epidermis As such,

plasma resurfacing has similarities to single-pass CO2

laser resurfacing A plasma cloud of electrons removed

by radiofrequency sparking of nitrogen gas is absorbed

by the skin, but the epidermis is not truly ablated In

process, it seems to resemble a medium-strength TCA

peel, but may give deeper and more impressive

results, seemingly without much risk of

hypopigmen-tation and scarring, although it is a comparatively new

technique The gentler approach, and the persistence

of partially injured epidermis as a biological dressing,

minimizes fluid loss, crusting, and delayed healing

Healing usually occurs within a week

There are some similarities regardless of the

resur-facing technique used Tumescent or local anesthetic,

combined with nerve blocks and at least oral sedation,

is usually employed Beyond this, conscious sedation

or general anesthetic may be used, especially for laser

resurfacing Post treatment, some method of dressing

(either closed or open) is used to protect the

de-epithelialized skin as it heals For at least 1 week, the

patient cannot be present at work or social

engage-ments In darker-skinned patients, post-inflammatory

hyperpigmentation is a virtual certainty; in Asian and

African-American patients, such color change may last

a year or longer before gradually resolving.The risk of

infection is mitigated by initiating oral antibiotics and

antivirals before the resurfacing procedure

ACNE SCAR TREATMENT BY

NONABLATIVE THERAPY

During the past 5 years or so, nonablative therapy has

largely replaced ablative therapy for the treatment of

acne scars In nonablative therapy, directed energy,

usually thermal, is used to induce tissue modification

and collagen remodeling in the dermis The benefits

compared with ablative therapy are that skin

de-epithelialization does not occur, and nonablative

therapy is therefore a ‘lunchtime’ procedure that is

associated with little or no downtime Transient

ery-thema and mild edema resolving over hours to days

are often the only post-treatment effects Since

nonablative therapy tends to be a milder procedurethan ablation, multiple treatments may be requiredand/or these treatments may be combined with otheracne treatment methods

Since heating of the dermis can induce remodeling ofthe dermis and improvement of embedded acne scars,

a range of laser and light devices can be used Indeed,virtually any laser or light device, used appropriately,can achieve modest improvement in acne scars Amongthose that have been used in this capacity are thepulsed-dye laser, the potassium titanyl phosphate(KTP) laser, and intense-pulsed light These are vascu-lar-selective machines that, apart from improving sur-face topography, can also reduce the erythema that mayencircle and hence accentuate acne scars of the centralface Multiple treatments, often 3–6 or more about amonth apart, are needed to reduce redness and causesome textural change

A class of nonablative lasers has been especially cessful at improving acne scars These mid-infraredlasers include the 1064 nm neodymium (Nd):YAG,13

suc-1320 nm Nd:YAG (Cool Touch),14–181450 nm diode(Smoothbeam),19and 1540 nm Er:glass (Aramis), aswell as intense-pulsed light machines with a similarrange (Titan, 1100–1800 nm) Such devices have beenshown in numerous studies to significantly improverolling, boxcar, and ice-pick scars of the cheeks, peri-oral areas, and elsewhere.The main limitation is intra-operative discomfort, which may be sufficient to requiretopical and oral pain medications In darker-skinnedpatients, the risk of postinflammatory hyperpigmenta-tion is significant and may suggest the use of the

1540 nm device

Nonablative therapy can also be performed with RFdevices, including those using monopolar and bipolartechnologies RF energy, in cadaver skin, can shrink thefibrous septae,20and may also have collagen-remodelingeffects.While it is typically used for tightening saggingfacial or body skin rather than for rectification of acnescars, RF treatment, like treatment with broadbandinfrared light, may ameliorate acne scars

When acne scars are mild, textural abnormalitymay be minimal, and the primary visual feature may be ahalo of erythema that highlights the scar Such rednesscan be removed by a series of treatments with vascular-selective lasers or light sources,21such as the pulsed-dyelaser, the KTP laser, and the intense-pulsed light device

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Post-treatment effects are minimal erythema and

edema, which resolve within a few hours to a day Such

treatments may be also appropriate for patients who

desire a very minimal intervention, and can tolerate

little or no downtime Acne excoriée, which may be

associated with erythematous macules, has also been

successfully treated with vascular laser and

psychother-apy.22 It is believed that erythematous acne scars can be

treated even when they are immature, by pulsed-dye

laser immediately after suture removal.23Unlike

erythe-matous macules, hyperpigmented and hypopigmented

macules are better managed passively Q-switched lasers

for pigment and tattoos are minimally effective in

reduc-ing post-inflammatory hyperpigmentation, and may

even exacerabate such pigmentation at high fluences;24,25

gentle nonablative glycolic acid, salicylic acid, Jessner’s

solution, and retinoic acid peels may be less prone to

aggravate brown areas.26,27In general, pigmentation of

scars in olive-skinned patients will fade gradually over

3–18 months, if strict sun avoidance and sun protection

are practiced in association with a topical preparation,

such as hydroquinone, kojic acid, and azelaic acid.28,29

White macules may be very difficult to treat, and may

only be transiently repigmented with repeated

treat-ments with the 308-nm excimer laser, phototherapy, or

application of autologous cultured melanocytes

Microdermabrasion, a topical therapy that entails

spraying of aluminum oxide crystals on the epidermis,

is popular and frequently touted as beneficial for acne

scarring.30However, objective evidence of the efficacy

of microdermabrasion for treatment of acne scarring

is minimal What little improvement can be achieved

appears to require repeated, intense sessions and the

elicitation of pinpoint bleeding, which is seldom

induced Microdermabrasion should not be confused

with dermabrasion, a highly effective ablative therapy

for acne scars

ACNE SCAR TREATMENT BY

PARTIALLY ABLATIVE THERAPY

For treatment of acne scars, resurfacing provides

max-imal improvement and nonablative therapy offers the

promise of convenience and safety To wed these two

desirable outcomes in a single therapy, so-called

‘par-tially ablative’ treatments have been devised These

methods are used to resurface only a portion of theskin area treated, thus allowing maintenance of skinintegrity, fewer side-effects, and more rapid healing.One pioneering method of partially ablative therapy

is fractional resurfacing Using a diode-pumped 1550 nmerbium laser, fractional resurfacing (Fraxel, ReliantTechnologies, Mountain View, CA) creates a gridpattern of microthermal zones of tissue coagulationbut an intact stratum corneum.31,32 Over a period ofdays after treatment, microscopic epidermal and der-mal necrotic debris is expelled, and collagen remodel-ing occurs at the affected areas A series of treatmentscan resurface virtually the entire surface area, but byfractionating treatments, downtime is minimized andthe serous crusting of typical resurfacing is avoided Ithas been shown that high-energy treatments are moreeffective for the treatment of acne scarring; such treat-ments do not ablate more surface area, but provide agreater volume of thermal injury

A simpler, less precise approach to partially ablativetherapy is skin rolling or needling These procedurespurport to achieve on a macroscopic level what frac-tional resurfacing can do on a microscopic level Inneedling,11a fine 30-gauge needle held by a hemostat

is used to serially puncture a 2–3 mm deep grid tern on the skin, including epidermis and dermis.Fibrous bands holding down acne scars are released,and the coagulum resulting from the pinpoint intra-dermal bleeding can raise depressed scars and instigategranulation tissue For larger scars, a tattoo gun with-out pigment11or a rolling pin may be used Rolling isperformed with a needle-studded rolling pin33 – ametal cylinder implanted with needle-like protrusions– that is pressed against the facial or extrafacial skinand rotated around the long axis to make an array ofmicroperforations until some bruising is observed Inboth rolling and needling, pinpoint bleeding occursand is managed by application of pressure Epidermalhealing occurs with minimal crusting in a few days,and dermal trauma culminates in collagen remodeling.This process, also referred to as ‘collagen inductiontherapy’ can be repeated a few weeks later.Anatomicalareas that respond poorly to this treatment include thenose and periorbital regions Synergies may accrue ifrolling is used in combination with other treatments,such as nonablative laser, vascular laser, subcision, orblood transfer

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pat-ACNE SCAR TREATMENT BY

INCISIONAL SURGERY

Apart from ablative, partially ablative, and nonablative

external smoothening techniques, cutting surgery can

be used to treat acne scars One minimally invasive

surgical technique for rolling scars is subcision, which

is preceded by instillation at the site of scarring of

anesthesia – local for small areas and tumescent

for larger areas Developed by Norman and David

Orentreich,34,35 subcision (Figs 8.4 and 8.5) requires

insertion of an 18–26-gauge Nokor or similar needle,

or even a blunt canula, into the superficial subcutis

Depth of insertion is contingent on the degree of scar

indentation, with intradermal positioning more

appro-priate for shallow scars and deep dermal placement for

deeper scars The needle is then rotated so that the

spearlike tip is parallel to the skin, and the needle is

used to tent the skin Back-and-forth rasping

move-ment of the needle along the underside of the dermis

releases fibrous attachments holding down scars and

stimulates the growth of reactive fibrosis that gradually

fills the deadspace underlying newly loosened scars In

a manner similar to liposuction, fanning movement of

the needle and triangulation of each scar from

differ-ent differ-entry sites helps elevate scars Especially if

wide-spread treatment is being performed, intraoperative

bruising and bleeding is minimized by using tumescent

anesthesia, or copious quantities of a dilute 0.5% caine with 1:200 000 solution, and allowing the anes-thesia to sit for 20–30 minutes before commencing

lido-Fig 8.4 Rolling scars amenable to subcision can occur

periorally, on the upper and lower cheeks, and at the temples

Subcision can also be highly effective for nasal scars (not

shown)

Fig 8.5 (a) In subcision, the rasping needle is used torelease the fibrous bands connecting rolling scars to the deepskin structures (b) Simultaneous tenting of the skin with theneedle minimizes the risk of injury to neurovascularstructures

a

b

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needle insertion Postoperative ecchymoses and edema

can last 1–3 weeks.To avoid a flare of cystic acne after

treatment, susceptible patients with some active acne

may be treated with oral tetracyclines for several

weeks before and after subcision

Individual deep boxcar or ice-pick scars can be

resis-tant to nonsurgical treatment At times, the best

approach can be to cut these out A time-honored

tech-nique uses a biopsy punch to treat such scars If the

targeted scar fits precisely within the punch,

circumfer-ential cutting with the punch can cause elevation of the

scar as lateral and deep fibrous bands are severed and the

plug containing the scar spontaneously elevates This is

referred to as punch elevation Alternatively, if the scar

is very deep and well embedded, the central plug may

be removed, as in the case of a punch biopsy Then the

created defect may either be sewn end-to-end, to create

a slit-like scar (i.e., punch excision), or filled with a

sim-ilar shaped plug harvested from an uninvolved scar (i.e.,

punch grafting) At times, a series of deep scars may be

present in a linear or curvilinear array Such scars may

be revised by removal of a strip of epidermis and dermis

using the techniques of elliptical excision and bilayered

closure with eversion If a patient requires punch or

lin-ear excision as well as resurfacing for treatment of acne

scars, it is preferable to perform the excisions first, as

the re-epithelialization following the ablative procedure

will conceal the excision lines

Perifollicular hypopigmentation of acne scars,

espe-cially those of the trunk, remains highly resistant to

treatment If papular and facial, hypopigmented scars

may be treated with fine-needle diathermy, and ing procedures useful in vitiligo may also be consid-ered Minigrafting is limited in efficacy, since thespread in pigment from the graft sites to the surround-ing scars appears to be restricted,36,37 but epidermalsuspensions of cultured and noncultured cells arepromising new therapies Newly available automatedcommercial kits for trypsin epidermal separation (Re-Cell) may simplify the grafting process.37,38

graft-ACNE SCAR TREATMENT BY FILLERS

Filler injection is a minimally invasive method ofscar improvement that can be combined with othertreatments Also known as soft-tissue augmentationmaterials, fillers can be autologous, heterologous, orsynthetic; additionally, they can be prepackaged orharvested prior to use

Until the 21st century, the primary Food and DrugAdministration (FDA)-approved prepackaged aug-mentation material was bovine collagen Since then,human-derived collagen (Cosmoderm and Cosmoplast),hyaluronic acid derivatives (Restylane, Juvederm,Hylaform, Hylaform Plus, and Captique), calciumhydroxyapatite (Radiesse – pending FDA approval,used off-label), and liquid silicone (used off-label)39have been used frequently (Table 8.1) While bovinecollagen required skin testing to exclude allergy,none of the newer fillers do, although they shouldnot be used in patients with known sensitivity to their

Table 8.1 Common fillers for acne scarring (USA)

Filler type Filler name Method of use Persistence

Human-derived

Autologous Blood aspirate Can be injected deep or superficially Weeks to months

Fat Injected deep for rolling scars Weeks to months, portion of effect

may be permanent Heterologous Human collagen Fine superficial scars, or layering in 2–3 months

dermis Non-human-derived

Temporary Hyaluronic acid Versatile, for deep and medium injection 6–9 months

Calcium Deep, for rolling scars (off-label) 1 year hydroxyapatite

Permanent Liquid silicone Rolling scars (not FDA-approved) Many years

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