Port-wine stains (PWSs) are benign congenital vascular malformations that most commonly occur as isolated lesions on the face, neck and trunk. The major indication for therapy in most patient, regardless of age, is psychological burden imposed by
the
PWSs.
A Candela SPTL-1 flashlamp-pumped pulsed dy laser (Candela Corp. Wayland, Mass.) using the principle of selective photothermolysis was used. Selective cutaneous vascular damages are influenced by the wavelength. pulse duration and energy density
of
the
laser.
To evaluate histopathological changes according to energy densities are essential to treat cutaneous benign vascular lesion by the iaser.
5 patients with PWSs were treated with the Candela SPTL-1 laser. Lesions were biopsied and analized immediately after laser exposure. 2 days and 7 days after laser exposure.
@ES The results were as follows :
@EN 1. Depth of penetration
The penetration depth was increased from .2mm to 1.9mm with energies ranging from 6J/㎠ to 10J/㎠ respectively.
2. Nonvascular damages of epidermis & dermis
Focal epidermal vacuolization has been observed in biopsy specimens immediately after laser exposure with energy density 6J/㎠. As energy densities increased from 6J/㎠ to 10J/㎠, histopathological changes got worsened with appearance of
vesicles.
subepi dermal seperations and epidermal necrosis.
2. Vascular damages of dermis
Multiple foci of agglutinated RBC, fibrin and platelet thrombi within the dermal blood vessels have been observed in biopsy specimens immediately after laser exposure.
There was a pattern of "acute vasculitis" in the upper dermis and a prominent perivascular neutrophilic responses in the mid-dermis 2 days after laser exposure.
Dermal vessels with smaller lumen and granulation tissue have been observed in biopy specimens 7 days after laser exposure.
In summary, penetration depth of laser beam and nonvascular epidermal and dermal damages were directly proportional ot the energy density of the laser. But 7 days after laser exposure, epidermis and dermis showed normal appearance without
detectable
scarring. This study suggested that Candela SPTL-1 laser is safe and has no scar formation on the treatment of PWSs. (Kor J Dermatol 1992;30(6):880-885)
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