Biomedical Engineering Reference
In-Depth Information
(
A
)
(
B
)
Figure 9.22
(
A
) Hypertrophic scarring developed following dermabrasion of the upper lip. (
B
) Complete resolution of hypertrophic scarring was seen after treat-
ment with intralesional 5-FU (45 mg/cc) and triamcinolone (1 mg/cc) in conjunction with treatment of wrinkling with Fraxel Re:Pair.
Three publications from China reported the clinical success
of low-dose (<10 mg/cc) IL 5-FU. Two publications (220,221)
were published in the Chinese literature. The fi rst article
(220) reported 35 patients with 51 keloids treated with 5-FU
(2-5 mg/cc) biweekly followed after 3-6 injections with IL ste-
roid. After 6 months, 45.7% had complete remission, 48.6 had
a great remission, and 2.9% had partial remission—a 97%
response rate.
The second article (221) reported 83 patients with bilateral
ear keloids. The keloids were excised and then treated with IL
low-dose 5-FU (not defi ned) and corticosteroid (not defi ned)
every 3-4 weeks. The mean treatment time was 7 months and
the mean follow-up after treatment was 9 months. There was a
100% response rate, with 47% having complete resolution and
53% having “effective” response.
The third study is a case report (222) of a 53-year-old
woman with a 28-year history of a chest keloid having 4+
pain, 4+ itching, 4+ erythema, and 2+ induration and mea-
suring 10 cm × 7 cm × 0.3 cm thickness. The lesion had failed
steroid therapy and cryotherapy. IL 5-FU was used in dosages
of 3.45-1.42 mg/cc given at 2-week intervals. TAC was also
used intralesionally at doses of 8.3-3.77 mg/cc. Fourteen
months after treatment, there was dramatic improvement in
the scar that had regressed to normal looking skin and was
asymptomatic.
As a consequence of the success of these low-dose stud-
ies and publications in the Chinese literature, Huang et al.
from Hong Kong proposed to alter the focus from cell destruc-
tion to the promotion of apoptosis and inhibition of fi broblast
proliferation with 5-FU (223). They studied the cellular
response of keloid fi broblasts at a range of doses as low as
1 mg/cc. At a dose of 25 mg/cc, there was complete inhibition
of cell proliferation and 80% cell mortality. In contrast, lower
doses (1-10 mg/cc) induced signifi cant inhibition of prolifera-
tion and cell apoptosis in a dose-dependent fashion but did
not cause immediate cell death. They found that 5-FU causes
G2/M cell cycle arrest and induces dramatic p53 and p21
accumulation together with a decrease in cyclin B1 and Bcl-2
levels. Both p53 and p21 are associated with cellular apoptosis.
After reading these studies, the senior author (REF) has
treated a small number of scars with low dose 5-FU (5 mg/cc)
successfully (Fig. 9.23).
conclusion
The treatment of scarring is very complex and cannot be
accomplished successfully by the use of a single modality. It is
a constant reality that each case must be analyzed carefully and
a specifi c approach is developed for that individual and for
each scar treated.
The availability of various vascular lasers, such as the V-beam
Perfecta, has defi nitely enhanced our ability to successfully
treat scars, particularly those with signifi cant erythema. In a
similar fashion, the advent of fractional lasers, such as the
Fraxel lasers, has added a new dimension to the treatment of
scars using both NAFR and AFR.
As far as dyspigmentation is concerned, the use of pigment
lasers such as the alexandrite laser to remove excessive pigment
and the use of the bimatoprost to stimulate pigment in areas of
hypopigmentation give us greater control over these issues.
There are numerous studies documenting the superiority of
IL 5-FU over corticosteroids in the treatment of hypertrophic
scarring and keloids. Greater effi cacy and dramatically lower
incidence of side effects have been seen. It is hoped that the use
of this drug in both prevention and treatment of scars becomes
more widespread.
By combining these modalities for use simultaneously, we
can achieve tremendous success (Figs. 9.24 and 9.25).
Early intervention has also been found to be critical and
has the potential to prevent scarring when done properly.
The optimum time for treatment has not been fi rmly estab-
lished, but various studies as well as the clinical experience of the
senior author are convincing that the earlier the better. It appears
clear that treatment at the fi rst signs of potential hypertrophic
scarring is critical in preventing and minimizing scarring.
