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Skin Phototypes:
Evolution and Present Status
Fitzpatrick, Thomas1,2
Massachusetts General Hospital1
Harvard Medical School2
Abstract-
When I introduced the concept of skin types (later called skin phototypes)
in 1975 (J Med Esthet 1975, 2:33-34) it was a practical proposal. At
that time (1974) we were introducing a new type of phototherapy utilizing
a new high intensity ultraviolet light source (UVA) plus and oral photoactive
drug (8-methoxypsoralen). This was a new concept of the beneficial action
of drug psoralen + UV (PUVA) which we called photochemotherapy. We conducted
a large multicenter trial with over 1000 participants in the USA and
the skin type classification was a practical method of estimating the
dose of UVA (in joules) based on the skin phototype. This proved to
be a successful method and less then 3.0% of the patients developed
phototoxic burns. The skin phototype classification has been criticized
for not being quantitative and objective methods were necessary to precisely
estimate the UV sensitivity. Subsequent studies have proved, however,
that, using image analysis and optical methods for melanin density of
surface corneocytes it has been shown that skin phototype and melanin
content have a significant correlation (Lu et al. Brit J Dermatology,
1996, 135:263-7). The skin phototype is not based on ethnicity but on
1) the skin color of a light-unexposed area, such as the inner arm and
2) the patients responses to average sun exposure: ease of sunburn and
depth of tan. light white SPT I burn easily with no suntan light
white SPT II burn easily with minimal suntan white SPT III
initial sunburn with moderate suntan light brown SPT IV } brown
SPT V } no burn and deep tan dark brown SPT VI } The term fair
or light commonly used for white skin include three different skin phototypes.
Keywords: Skin
phototype, UVA, Psoralen
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