Argon e YAG laser no tratamento de neovascularização de córnea

Argon and YAG laser in the treatment of corneal neovascularization

RESUMO

Neovascularização de córnea (NC) é considerado um dos maiores fatores de risco para rejeição em transplantes de córnea. Várias formas de tratamento para NC tem sido sugeridas incluindo esteróides, irradiação, tiotepa, ciclocrioterapia e outros. Tratamento para NC usando Argon e YAG laser, tem melhorado o prognóstico de transplante de córnea e parece ser seguro e efícaz. Não há porém, na literatura pesquisada, estudo comparando as duas formas de tratamento. Em estudo randomizado, comparamos as duas formas de tratamento para NC usando Argon e YAG laser para avaliar sua segurança e eficácia, em pacientes com NC refratária ao tratamento convencional.

Em nosso estudo, Argon laser mostrou ser terapia alternativa e/ou complementar útil no tratamento de NC refratária aos tratamentos convencionais. Pacientes tratados com Argon tiveram melhora clínica estatisticamente significativa dos parâmetros analisados (diminuição da neovascularização por quadrante e diminuição da deposição de lipídios), em comparação ao grupo tratado com YAG laser (x² =14,87).

Palavras-chave:
Neovascularização corneana; Transplante de córnea; Tratamento com laser; Argônio; YAG

SUMMARY

Corneal neovascularization (CN) is a major risk factor for corneal graft rejection. Many forms of treatment have been suggested including steroids, irradiation, thiotepa, cyclocriotherapy and others.

Lasertherapy for CN, using Argon and YAG laser, is a new modality of treatment, that it is told to be safe and effective, improving penetrating keratoplasty results. In this paper, we compare two forms of treatment for CN using Argon and YAG laser to access their safety and effectiveness in a randomized study.

In our study, Argon laser has shown being an effective alternative and/or complementary therapy in the treatment of refractory CN. Patients treated with Argon laser had statistically significant improvement of the analyzed parameters (improvement of the neovascularization per quadrant and decrease of the corneal lipid deposition), compared to the group treated with YAG laser (x² =14.87).

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• Departamento de Oftalmologia da Santa Casa de São Paulo - Secção de Córnea e Doenças Externas

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Datas de Publicação

• Publicação nesta coleção
  Oct 1997