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Advances in technology and well documented clinical studies
continue to expand the list of disorders amenable to laser therapy. In this issue, Tan and Vinciullo report their study of
186 children and adults with port-wine stains (capillary
malformations) treated with a flashlamp-pumped tunable dye laser in
Perth, Western Australia. They confirm reports from other countries
of its efficacy and safety. Preferential uptake of yellow laser light
(wavelength, 585 nm) by haemoglobin, combined with very short
(450-µs) laser pulses, ensures maximum damage to small blood
vessels with minimum heat transfer to surrounding tissue (selective
photothermolysis).1
Good-to-excellent responses were seen in 78% of
patients. The results are similar to those of a recent study at Royal
Prince Alfred Hospital (RPAH), Sydney, and Flinders Medical Centre,
Adelaide.2 Treatment failures may be
related to depth and diameter of blood vessels, as the laser beam
penetrates only about 1 mm. Given the well documented, sometimes
severe but often hidden, psychological impact of a disfiguring
port-wine stain, its potential complications and the lack of
significant therapeutic alternatives, these results are
impressive.
However, critical issues apart from efficacy and safety include cost
and access to treatment. The RPAH/Flinders study estimated the cost
of treating a port-wine stain involving one cheek to be about
$700-$1800 in an adult. This cost includes staff and topical or local
anaesthesia, but not general anaesthesia, which is needed for most
children. We must also add the laser capital costs (currently $150
000-$200 000) and substantial running costs.
Will all patients with port-wine stains have access to a treatment now
proven to be efficacious and safe? Ideally, all affected patients
should be assessed at or soon after birth and treatment begun in the
first two years of life and completed before the potential
psychological impact of being a "marked child"3 has developed.
Until recently at RPAH the estimated time to completion of treatment
for children after assessment was 3.5 years. The service has been
advertised only to dermatologists, because resources are too
limited to treat the estimated potential number of patients,
although the recent purchase of a third generation laser may increase
the number able to be treated.
Public hospital dermatological laser services vary between States
and generally range from severely restricted to non-existent. Now
that Australian studies have addressed issues of efficacy and cost,
it is up to State Governments and the Federal Government to urgently
establish appropriate funding arrangements. There is a large
backlog of older children and adults who would benefit greatly from
treatment. In the medium to long term, even with current technology,
these patients could be treated, leaving a steady-state situation
with only children in their first 2-4 years needing treatment.
Treatment with the yellow-light laser is not confined to port-wine
stains, but can be used for many other conditions characterised by a
real or apparent excess of small blood vessels close to the surface of
the skin. Proliferating or ulcerating capillary haemangiomas that
affect vital structures (e.g., eyes, nose, mouth, pharynx and
genitalia) in babies and young children have been shown in both
Australia and other countries to respond to treatment with the
flashlamp-pumped dye laser. This treatment is often urgent or
semiurgent, depending on the rate of proliferation of the
haemangioma or rate of ulceration and tissue destruction.
Has technology in this area gone as far as it can? The answer is no. Newer
lasers are now available that are able to operate several times faster
than the initial pumped dye lasers and may require less maintenance.
We await lasers that are more portable, cheaper and able to treat at a
deeper skin level than current technology allows.
Timely and affordable access to treatment for any patient, young or
old, affected with a port-wine stain is the goal. Whether this is
realised depends on a commitment by State and federal health funding
bodies to recognise the extent of the problem, acknowledge the long
term benefits of early treatment and provide an adequate funding
mechanism.
Margaret M Stewart
Visiting Medical Officer, Department of Dermatology
Royal Prince Alfred Hospital, Sydney, NSW
- Anderson RR, Parrish JA. Selective photothermolysis: precise
microsurgery by selective absorption of pulsed radiation.
Science 1983; 220: 524-527.
-
Stewart M, Hailey D, Angel A. Yellow light lasers in dermatology.
Canberra: Australian Institute of Health and Welfare, 1995: 1-43.
-
Lanigan SW, Cotterill JA. Psychological disabilities amongst
patients with port wine stains. Br J Dermatol 1989; 121:
209-215.
©MJA 1999
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© 1999 Medical Journal of Australia.
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