Efeito da remoção seletiva da sutura no astigmatismo nos transplantes de córnea pós-ceratocone The effect of selective suture removal on astigmatism following penetrating keratoplasty in keratoconus

OBJETIVO: Demonstrar o efeito e os resultados da remoção seletiva da sutura sobre o astigmatismo nos três primeiros meses de transplante de córnea pós-ceratocone. MÉTODOS: Realizamos um estudo longitudinal observacional retrospectivo, revisando aleatoriamente os prontuários médicos de 50 pacientes, submetidos à transplante penetrante de córnea por ceratocone, realizados pelo mesmo cirurgião, no período entre 2000 e 2002, no Instituto de Oftalmologia Tadeu Cvintal. Os transplantes foram realizados com a mesma técnica cirúrgica com oito pontos isolados e sutura contínua e controle ceratoscópico per-operatório. Em todas as visitas foram mensuradas a melhor acuidade visual corrigida, ceratometria e refração. A remoção seletiva da sutura e redistribuição da sutura contínua ocorreu invariavelmente no primeiro mês de pós-operatório. RESULTADOS: No primeiro mês de pós-operatório, antes do início de remoção de suturas a acuidade visual média pré-remoção foi de 0,4 log MAR. Após remoção seletiva escalonada de suturas e estabilização do astigmatismo, a acuidade visual média pós-remoção foi de 0,07 log MAR, diferença estatisticamente significativa (pPURPOSE: To analyse the corneal astigmatism after transplantation as well as to demonstrate how post-surgical handling of sutures affects the refractive and visual outcome in patients submitted to cornea transplantation by keratoconus with three to six years of follow-up. METHODS: Non-controlled longitudinal observational secondary clinical study. Fifty records of patients submitted to penetrating keratoplasty between 2000 and 2002 have been reviewed, including 50 eyes of 50 patients operated under the same surgical technique by the same surgeon. Follow-up time ranging from three to six years. Main outcome measures were keratometry, static refraction and computadorized keratometry. Tstudent and Wilcoxon tests were used for paired samples to assess respectively possible differences between means and medians. RESULTS: The average patient age was 24.8 years. The average of the pre-visual sharpness was 0.8 log MAR and changed to 0.4 log MAR before removing the sutures and to 0.4 log MAR after the handling/removal of sutures (p< 0.0001). The topographic astigmatism varied from 2.8D before transplantation to 3.8D in the following 30 days and reached an average of 2.8 after the handling/removal of sutures (p= 0.0229). The corneal curvature changed from 51.5 to 45.2 (p= 0.0000001). 23.3% of the patients presented myopic and hypermetropic deviation averages of respectively -3.17D and +2.07D. 113 days was the average for the beginning of the suture removal. CONCLUSION: Although the selective and stepwise removal of sutures requires more visits of the patient to the doctor in the first months that follow the penetrating keratoplasty, the good visual and refractive results corroborate not only the importance of the post-surgical attendance, but also the identification and immediate intervention in the selective suture removal of keratoplasty