Port-wine stains (PWS)
are tender vascular (blood
vessel) deformities in
the surface of the dermis.
PWS is a congenital vascular
deformity and is of the
capillary kind.
PWS is present at birth
and do not obscure on their
own. It occurs as a permanent
stain, which grows darker
at the age of 10–14
years. If it is not treated
at this early stage, by
the age of 20 the lesions
mature into a blemishing
hypertrophy accompanied
by varying nodular formations.
Lasers are considered
an effective means of correcting
PWS by lightening the scars
and decreasing their number
and size, though achieving
only a partial clearance.
The pulsed tuneable dye
laser (PDL) has become
the standard treatment
of PWS proving high effectiveness
and minimum side-effects.
The first-generation PDLs
with 577 nm or 585 nm wavelengths
and 0.45 ms pulse width,
have proved the safest
and most efficient among
PDLs. However, in many
patients where the PWS
scars are unmanageable,
various other wavelengths
have also been experimented
with.
The search for better
correction of the resistant
types, has led to research
and improvisation of the
initial PDL formulations.
Many other types of lasers
and non-coherent light
sources have also been
tried out in PWS treatment,
with varying results. Despite
the laser types, the number
of laser applications required
to achieve a satisfactory
outcome is still variable.
However, before we go into
the details of the various
treatment options, it is
important to know certain
key diagnostic principles
involved in laser treatment
of PWS.
Morphological prognostic
factors: This includes
the location of the blood
vessels that require treatment.
The ones with superficial
depth respond better to
the lasers. The location
helps determine how well
the PWS will respond to
the laser.
The gross color of PWS:
Lasers are supposedly more
effective on red lesions
than pink or purple ones.
Location and size of PWS:
PWS lesions on the head
and neck are considered
more receptive to lasers,
than other body locations.
Then again, wider lesions
require to be subjected
to greater laser exposure
than thinner lesions.
Age of the patient: This
is still a debated factor.
Though some early studies
have reported that treatment
of PWS is more effective
at younger ages, there
has been a counterpoint
that treatment at an early
stage would be futile since
there is bound to be PWS
enlargement during the
growing years.
Once these prognostic
factors have been dealt
with, the various laser
therapy options are:
Second generation pulsed
dye lasers
Second-generation pulsed
dye lasers are adaptations
of the original PDL mechanisms.
The key areas of adaptations
are in longer pulse widths,
longer wavelengths, higher
fluences and use of potent
cooling mechanisms. Some
of these lasers wavelengths
(with variations in other
parameters such as pulse,
fluences, exposure period
etc.) that been experimented
with and have proved effective
in the treatment of PWS
are:
- The Sclerolaser with
595 nm wavelength
- PDL
with 600 nm wavelength
- Second-generation
long-pulsed tuneable
dye laser (LPTDL)
with wavelengths
between 585 to 600 nm.
However, in most of the
cases one cannot pinpoint
the exact modification
that has improved the effectiveness
of the therapy, especially
if there is a variation
in various settings simultaneously
and the study group is
small. Moreover, theses
modifications are also
case specific with different
patients responding to
different alterations in
wavelengths, pulse widths
and fluences.
Second-generation PDLs
have also proved significantly
beneficial in the treatment
of PWS cases that have
failed to respond to first-generation
PDLs. These second-generations
PDLs are:
- PDL with a longer pulse
width
- High fluence
long-pulsed dye laser
with cryogen
cooling, but with greater
side effects. LPTDL
at 595 nm with dynamic
cooling
proved substantially
effective, with the
highest fluence
and shortest pulse
showing best results.
Multiple pass treatment
Multiple pass laser irradiation
is a current development
in laser-assisted PWS correction.
This process implements
two PDL pulses for every
laser sitting, the first
of 590–600 nm of
1.5 ms and the second of
585 nm of .45 ms. Hypothetically,
the first application aims
the vessels at greater
depth and the second pass
aims the superficial and
smaller vessels. This method
was reported to be highly
effective in four hypertrophic
PWS patients, who were
subjected to three to five
laser sessions. They also
showed maximum tolerance
and minimum side-effects.
Other lasers
Despite the effectiveness
of PDLs in PWS treatment,
there are various lesions
that remain unmanageable
and resistant. The alternative
laser-assisted options
applicable in such cases
are:
- The potassium titanyl
phosphate (KTP) laser
of 532 nm wavelength
- Longer
wavelength lasers such
as the Alexandrite
(wavelength of 755
nm) and Nd:YAG (wavelength
of 1064 nm), especially
in patients with large,
deeper PWS warps and
advanced
cases.
Laser treatment of PWS
is evolving each day with
more research to comprehend
vascular responses of PWS
to various lasers types.
The aim is to customize
laser therapy to individual
patient requirements by
adapting both the kind
of laser and its associated
settings. Moreover, this
also includes the very
vital factor of patient
comfort and satisfaction,
as at the end of it all
this is what makes a treatment
dynamic and effective.
