Acne affects 80% of people 11 to 30 years old with up to
95% of these patients ultimately left with some degree
of scarring.1 Acne is the most common cause of facial
scarring and results in considerable physical and psychiatric
morbidity. Of those patients who end up in our offices seeking
help, the choice of treatment is generally dictated by several
factors including the severity and morphology of lesions, patient
expectations, cost, and the side effect profile.
Before initiating treatment, it is important to give the patient
a handheld mirror and explain to them the difference
between active acne lesions, post-inflammatory hyperpigmentation
(PIH), and true scarring. Too often a patient is
frustrated by what they perceive as extensive scarring when
they truly have severe PIH, thus requiring a very different set
of treatments than those used for scarring. Acne scars can be
either hyertrophic or atrophic. Hypertrophic scars respond
well to repeated intralesional injections of corticosteroids,
which is generally considered the first-line therapy.2 Intralesional
5-fluorouracil (5FU), which has been shown to reduce
fibroblast proliferation, is also very effective, especially
when combined with the 585-595nm pulsed dye laser (PDL).3
Fitzpatrick describes a protocol of using 0.9cc of 50mg/cc of
5-FU (ie, 45mg) combined with 0.1cc of 10mg/cc of Kenalog
in the same syringe with 0.05cc injected per site, with 1cm
between sites.3 Injections are combined with PDL treatment
at 6 J/cm2 with the laser being performed first. Injections are
initially performed as often as 2 to 3 times per week until response
is noted at which point the interval can be increased
to every 2 to 4 weeks.
The majority of acne scars are atrophic and can be categorized
based on morphology as rolling, boxcar, or icepick.4 Rolling
scars are depressed, distensible scars that, of the three types,
are generally considered the most responsive to treatment.
Boxcar scars are punched-out, u-shaped scars that often require
punch excision techniques. Ice pick scars are narrow,
v-shaped scars that extend to the subcutaneous fat and also
often require surgical intervention. Approaches to the treatment
of atrophic acne scars can be divided into three general
categories: resurfacing techniques, dermal fillers, and surgical
techniques. It is critical when treating acne scars to appropriately
manage patient expectations, explaining that scarring
is permanent. Thus the goal of treatment is always improvement
of, not elimination of their scars. It is also important for
providers to keep in mind that what might seem like a minor,
even trivial improvement to us, may be life changing for a
patient who has had a face full of scars looking back at them
in the mirror for 20 years.
Resurfacing Techniques
Dermabrasion
Dermabrasion removes the epidermis and part of the upper dermis
and thus can be utilized to treat shallow, rolling, or boxcar
scars. The outcome is largely technique and operator dependent
with potential risks including sustained erythema and
PIH. The technique has somewhat fallen out of favor with the
advent of the fractional resurfacing lasers, but dermabrasion
still has a place in the armamentarium as a low-cost treatment
option with relatively little down time. Dermabrasion can also
be performed prior to chemical peels to increase the depth of
penetration of the peeling agent.
Chemical Reconstruction of Skin Scars (CROSS)
Trichloroacetic acid (TCA) CROSS involves the serial application
of 90 to 100% TCA to scars using a narrow wooden
applicator until a white frost appears. The application of TCA
results in necrosis of the epidermis and of dermal collagen
with subsequent reorganization of the dermis and an ultimate
increase in volume.5 The procedure is repeated at 4 week intervals
for 3 to 4 treatments. TCA CROSS is a relatively quick
and easy office procedure with minimal down time and low
cost to both patient and practitioner. TCA CROSS may offer
some degree of efficacy even for ice pick scars that would otherwise
require punch excision. Because the treatment area is
so focal, CROSS can be safely utilized in patients with skin of
color, although most advise priming with hydroquinone 4%
and tretinoin 2 weeks before treatment.6 Risks of TCA CROSS
include atrophy that typically improves spontaneously as
well as post-inflammatory hyperpigmentation (PIH), which