Luz intensa pulsada no fotoenvelhecimento: avaliação clínica, histopatológica e imuno-histoquímica

FUNDAMENTOS: A luz intensa pulsada tem sido muito utilizada no tratamento do fotoenvelhecimento sem completo conhecimento de seu mecanismo de acao. OBJETIVO: Estudar a acao da luz intensa pulsada no fotoenvelhecimento e na resposta imunologica cutânea por meio de estudo clinico, histopatologico, avaliando celulas de Langerhans (CD1), expressao da molecula de adesao intercelular, de linfocitos CD4 e CD8 e quantificacao de colageno e fibras elasticas. METODOS: Um total de 26 pacientes, com idades entre 40 e 65 anos, com fototipos II a III de Fitzpatrick, foram tratadas do fotoenvelhecimento usando LIP, em 5 sessoes, com intervalo mensal, durante o ano de 2006. Todas as pacientes foram submetidas a avaliacao histologica e imuno-histoquimica 6 meses apos o tratamento. RESULTADOS: Ao termino do tratamento, houve melhora clinica em 76,92 por cento dos casos, estando relacionada ao aumento significante de fibras colagenas (51,33 por cento) e elasticas (44,13 por cento). O tratamento com luz intensa pulsada promoveu reducao de linfocitos CD4 e nao alterou a intensidade de linfocitos CD8. Alem disso, promoveu aumento significante de pequenos vasos sanguineos, nao ectasicos, molecula de adesao intercelular positivos. CONCLUSAO: O tratamento facial com luz intensa pulsada promoveu intensa melhora clinica que foi comprovada pelo estudo histopatologico da pele, constituindo boa opcao de tratamento para o fotoenvelhecimento cutâneo, por ser tecnica nao- ablativa, segura e eficaz. BACKGROUND: Intense pulsed light has been used in the treatment of photoaging without a full understanding of its mechanism of action. OBJECTIVE: To study the effect of intense pulsed light on photoaging and on the skin immune response by means of a clinical and histopathological study, evaluating Langerhans cells (CD1), expression of intercellular adhesion molecule, of CD4 and CD8 lymphocytes and quantification of collagen and elastic fibers. METHODS: In 2006 a total of 26 patients, aged 40 to 65 years, with phototypes II to III (Fitzpatrick scale), were treated for photoaging using intense pulsed light in five sessions with a monthly interval. All the patients were subjected to histological and immunohistochemical evaluation 6 months after treatment. RESULTS: At the end of the treatment clinical improvement was observed in 76.92 percent of cases. This improvement was associated to a significant increase of collagen (51.33 percent) and elastic (44.13 percent) fibers. Intense pulsed light treatment led to a reduction of CD4 lymphocytes and did not alter the amount of CD8 lymphocytes. It also led to a significant increase of small, nonectatic blood vessels, positive intercellular adhesion molecule. CONCLUSION: Facial treatment with intense pulsed light promoted major clinical improvement that was confirmed by histological examination of the skin. This technique is a good treatment option for skin photoaging because it is non-ablative, safe and effective.