No abstract

To investigate vessel coagulation depth and tissue damage in therapy with the flashlamp-pumped pulsed dye laser (585 nm, 5 mm spot size, 450 microsecond pulse duration, 6-8 J/cm2), we used the nitroblue-tetrazolium chloride stain in 22 post-treatment biopsy specimens from patients with port wine stain. With this method, thermally damaged tissue can be easily differentiated from unchanged tissue to the level of single cells. The results showed that in superficial port wine stain vessels up to 150 microns in diameter, vessel coagulation was complete and selective without further dermal damage. With the increase of vessel diameter, strong superficial hemoglobin absorption led to only partial vessel-wall coagulation and, in some cases, to superficial dermal damage. Likewise, deeper vessels were not coagulated because of shadow effects by superficial vessel layers. Thus, the overall vessel-wall coagulation depth of the flashlamp-pumped dye laser was limited to a maximum of 0.65 mm (mean 0.37 mm). In addition, some degree of epidermal damage was present in most specimens, which significantly increased with epidermal melanin content and resulted in epidermal coagulation and blistering in pigmented skin. Our results explain the occurrence of crusting, hyperpigmentation, and hypopigmentation in therapy with the flashlamp-pumped dye laser and its limited effect on dark or hypertrophic port wine stains in adults featuring large vessel diameters or multiple vessel layers.

We report a case of recalcitrant pruritus after infusion therapy with hydroxyethyl starch (HES) for sudden deafness. The diagnosis was confirmed by detection of typical HES storage vacuoles within dermal macrophages and perineural cells. Treatment with antihistamines and antipruritic agents, UVB irradiation, and neuroleptic drugs, was ineffective. Topical capsaicin (0.05%) twice daily produced excellent symptomatic relief, without side-effects.

We describe a 65-year-old woman who had had wart-like lesions on the hands, lower arms and forehead for about 45 years. She had already had several basal cell carcinomas excised. Histological study, electron microscopy and in situ hybridization [human papilloma virus (HPV)-types 5/8/12/14/19-23/25/36] of skin biopsies confirmed a diagnosis of epidermodysplasia verruciformis (EV). Photodynamic therapy (PDT) was performed using a 20% 5-aminolaevulinic acid ointment applied for 6 h to the lesions and irradiating using an incoherent light source (lambda = 580-740 nm, 160 mW/cm2, 160 J/cm2). Following PDT, blistering and crusting of the lesions occurred, but these healed completely within 2-3 weeks without scarring, and the cosmetic result was excellent. Six months after PDT a skin biopsy was taken. In situ hybridization was positive for HPV type 8 in skin which was clinically and histologically normal. Twelve months after PDT a few lesions had recurred on the hands. Although permanent cure of EV cannot be achieved by any therapy at present and single lesions continue to appear in this patient, topical PDT might result in better control of HPV-induced lesions.

The flashlamp-pumped pulsed dye laser (FPDL) was the first laser system specifically developed for the treatment of cutaneous vascular lesions such as port-wine stains (PWS), telangiectases and haemangiomas. Its theoretical advantages have been verified by numerous excellent clinical results. As there are few systematic studies on the adverse effects of this laser system, we investigated 100 consecutive patients who received FPDL therapy of PWS. Pain during and after laser therapy was a common complaint. Post-treatment erythema occurred in 29%, oedema in 73%, formation of bullae in 1%, and serous crusting in 46-83% of patients (based on our observations and the patients histories, respectively), all of which lasted for a maximum of 7 days. Furthermore, complications such as impetigo-like crusting occurred in 25%, bleeding in 12%, a pyogenic granuloma in 1%, hyperpigmentation in 27%, hypopigmentation in 1%, atrophic scarring in 3%, and an hypertrophic scar in 1%. Although most of these changes were only focal, and were predominantly transient, our results indicate that the incidence of side-effects and complications produced by the FPDL (wavelength 585 nm, pulsewidth 450 microseconds) may be higher than previously documented in the literature.