Gustavo Teixeira Grottone

Usefulness of corneal esthesiometry for screening diabetic retinopathy

OBJECTIVE To assess the usefulness of corneal esthesiometry for screening diabetic retinopathy. METHODS A cross-sectional study was carried out comprising 575 patients attending a diabetic retinopathy-screening program in the city of São Paulo. Corneal esthesiometry was assessed with the Cochet-Bonnet esthesiometer. The presence of diabetic retinopathy was detected with indirect fundoscopy. The validity of corneal esthesiometry in identifying diabetic retinopathy was evaluated by the Receiver Operating Characteristic (ROC) curve. RESULTS Sensitivity and specificity analyses of the corneal esthesiometry for detecting the stages of diabetic retinopathy using different cut-offs showed values less than 80%. The best indices (72.2% sensitivity and 57.4% specificity) were obtained for the identification of patients with proliferative diabetic retinopathy. CONCLUSIONS In the study series, corneal esthesiometry was not a good indicator of diabetic retinopathy.

Endothelial keratoplasty: evolution and horizons

Endothelial keratoplasty has been adopted by corneal surgeons worldwide as an alternative to penetrating keratoplasty (PK) in the treatment of corneal endothelial disorders. Since the first surgeries in 1998, different surgical techniques have been used to replace the diseased endothelium. Compared with penetrating keratoplasty, all these techniques may provide faster and better visual rehabilitation with minimal change in refractive power of the transplanted cornea, minimal induced astigmatism, elimination of suture-induced complications and late wound dehiscence, and a reduced demand for postoperative care. Translational research involving cell-based therapy is the next step in work on endothelial keratoplasty. The present review updates information on comparisons among different techniques and predicts the direction of future treatment.

Descemet's membrane endothelial keratoplasty with a simplified technique and low complication rate: the samba technique

PURPOSE We report a simplified Descemets membrane endothelial keratoplasty (DMEK) technique that involves safe and effective preparation and introduction, correct orientation, and easy unfolding of the donor graft inside the recipient anterior chamber. METHODS In this retrospective study, we assessed the surgical outcomes of 26 eyes of 23 consecutive patients (mean age, 61.2 ± 11.4 yr; range, 39-82 yr) with Fuchs endothelial corneal dystrophy (n=19) or bullous keratopathy (n=7) who underwent the Samba technique, a simplified DMEK method, at the Sorocaba Ophthalmology Hospital, Sorocaba Eye Bank, Sorocaba, Brazil, between August 2011 and July 2012. RESULTS Of the 26 operated eyes, only two (7.7%) experienced partial graft detachment requiring rebubbling, and in those eyes, the graft was reattached successfully with one air bubble. There were no cases of primary graft failure, tissue loss, or pupillary block. All patients with good visual potential achieved a best-corrected visual acuity of 20/30 or better at 6 months, and 82.6% achieved a best-corrected visual acuity of 20/30 or better 1 month postoperatively. CONCLUSION In this retrospective study, the Samba technique, a simplified DMEK procedure, was safe and effective, with an acceptably low rebubbling rate and no incidence of primary graft failure or pupillary block. Moreover, rapid and nearly complete visual recovery was achieved. This simplified DMEK technique can be adopted by corneal surgeons worldwide as a primary treatment for endothelial dysfunction with a less steep learning curve and low rate of postoperative complications.

Alterações biomecânicas da córnea porcina com riboflavina fotossensibilizada por luz não-ultravioleta

OBJETIVO: Demonstrar a possibilidade de alterar a plasticidade do estroma corneano atraves da utilizacao do agente fotossensivel riboflavina associado ao uso de iluminacao nao-ultravioleta. METODOS: Experimento prospectivo duplo cego. Vinte e cinco olhos de porcos enucleados ate 24 horas antes do experimento, foram divididos nos seguintes grupos: Grupo RB01+L-Riboflavina 0,1% com irradiacao de luz azul; Grupo RB01-Riboflavina 0,1% sem irradiacao de luz azul; Grupo RB05+L-Riboflavina 0,5% com irradiacao de luz azul; Grupo RB05-Riboflavina 0,5% sem irradiacao; Grupo L-Solucao salina balanceada e irradiacao de luz azul. RESULTADOS: Apos o tratamento das informacoes dos grupos estudados, obtivemos diferencas estatisticamente significantes no grupos RB01+L e RB05+L(p<0,05). Os grupos sem irradiacao de luz azul e o grupo somente com irradiacao da luz azul sem riboflavina, nao apresentaram diferencas estatisticamente significantes. CONCLUSAO: A utilizacao de riboflavina para efetuar o processo de aumento de ligacoes covalentes entre as fibrilas colagenas pode ser uma das chaves para o controle de doencas da cornea como o ceratocone. Nas concentracoes estudadas e doses de irradiância concebidas, o processo de aumento das caracteristicas biomecânicas da cornea foram obtidas com sucesso.

Análise da pressão intra-ocular após ceratectomia fotorrefrativa com excimer laser

Objetivo: Comparar os valores pre-operatorios da pressao intra-ocular (Po) com os valores pos-operatorios em pacientes submetidos a ceratectomia fotorrefrativa com excimer laser, bem como, avaliar os efeitos do uso de corticosteroide topico na Po nesse grupo.Pacientes e metodos: Foram analisados retrospectivamente 122 pacientes submetidos a ceratectomia fotorrefrativa com excimer laser para correcao de miopia, no periodo de fevereiro de 1994 a dezembro de 1996. Esse grupo teve sua Po tomada com o tonometro de aplanacao de Goldmann no pre-operatorio, 30o e 60o dias e sexto mes pos-operatorio. Receberam cuidados pos-operatorios padronizados, incluindo o uso de corticosteroide topico.Resultados: Foi observado um aumento estatisticamente significante em relacao aos valores pre-operatorios nas medias da Po no 30o dia pos-operatorio, ao passo que no pos-operatorio de seis meses obteve-se diminuicao estatisticamente significante nos valores medios da Po em relacao ao pre-operatorio.Conclusao:Nas fases iniciais do periodo pre-operatorio, observou-se um aumento da Po possivelmente relacionado ao uso de corticosteroides. Apos 6 meses, os valores da Po foram estatisticamente menores que os pre-operatorios.