OBJECTIVES: To describe the indications for and visual outcomes of intrastromal corneal ring segment implantation. METHODS: A large retrospective case-series chart-review study was conducted using Sorocaba Ophthalmological Hospital medical records. This study included 1222 eyes (1196 patients) that were surgically treated between November 2009 and December 2012. The following preoperative data were collected: age, gender, type of medical care and funding source, surgical technique, best-corrected visual acuity, manifest sphere and cylinder refractive error, maximum and minimum central keratometry, and pachymetry measurements of the cornea at the thinnest point and at the ring channel. The postoperative best-corrected visual acuity and patient satisfaction were also determined. The cases were classified into six groups: four keratoconus groups (severe, advanced, moderate and mild), a pellucid marginal degeneration group and a post-graft irregular astigmatism group. This study was approved by the Brazilian Registry of Clinical Trials (UTN number 1111-1182-6181, TRIAL RBR-6S72RF). RESULTS: The age (mean±standard deviation) of the patients was 31.0±10.0 years. The most prevalent pathology was keratoconus (1147 eyes, 93.8%). A correlation was found between ectasia severity and medical assistance (p<0.001), and the most serious cases was treated by the Brazilian public health system. No complications were found in a total of 1155 surgeries, and after surgery, 959 patients were satisfied. Among the 164 dissatisfied patients, the majority failed to show improved best-corrected visual acuity. CONCLUSION: Patients in the public health system underwent surgical intervention for keratoconus later than those with private sources of funding. In the vast majority of operated cases, the patients reported improvements in vision.

OBJETIVO: Investigar se há diferença no peso e volume das gotas de colírios análogos das prostaglandinas em ângulos de gotejamento de 45º e 90º com relação ao plano horizontal. MÉTODOS: Foi realizado estudo experimental utilizando os colírios latanoprosta, travoprosta e bimatoprosta, pelo qual se gotejava as soluções com angulação de 45º e 90º. Estes colírios foram escolhidos em virtude do seu uso rotineiro em oftalmologia e do seu custo. A primeira gota e dez gotas seguintes foram pesadas em ângulo de 45º e 90º. A análise estatística foi realizada por meio do programa SPSS® 12.0 (Microsoft), utilizando o teste de variância ANOVA, sendo considerada diferença estatisticamente significante um valor P<0,001. RESULTADOS: Verificou-se que há diferença no peso, e conseqüentemente no volume, das gotas instiladas a 45º e a 90º dos colírios de travoprosta e bimatoprosta. Para o colírio travoprosta o gotejo a 45º produz uma gota menor que em 90º. O inverso ocorre para o colírio de bimatoprosta. Já para o colírio de latanoprosta, não houve diferença estatisticamente significante. CONCLUSÕES: Como houve diferença estatística no peso das gotas de dois colírios análogos das prostaglandinas e em outro não se verificou esta variação, - e como este possui relação direta com o volume - infere-se que devemos ser críticos diante de estimativas de custo ou duração da terapia com base no gotejamento dos colírios considerando número de gotas por frasco e volume.

PURPOSE: To investigate if there is any difference in volume and drop weight of prostaglandin analogs when adopting drip angles of 45º and 90º, regarding a horizontal line. METHODS: An experimental study was conducted using the follow ophthalmic solutions: latanoprost, travoprost and bimatoprost. In this study the ophthalmic solutions were dripped according to an angle of 45º or 90º. Prostaglandin analogs were chosen due to their common use in ophthalmology and their cost. The first drop and other ten drops were weighed, alternating the drip angle (45º or 90º). Statistical analysis was done with SPSS® 12.0 (Microsoft), using quantitative comparisons with the ANOVA test. An odds value (P) below 0.001 was considered a statistical significant difference. RESULTS: We verified differences in weight and size of the travoprost and bimatoprost drops instilled at 45º and 90º. The drip at 45º produces a smaller drop of travoprost (P<0.001), and the inverse occurs for bimatoprost. There were no statistical significant differences in weight of latanoprost drops according to the instillation angle. CONCLUSIONS: Once there was statistical difference in weight - which has direct relationship with size - of the drops of two kinds of prostaglandin analogs and in another one we did not observe this variation, we infer that cost and therapy duration estimates should be analyzed carefully, especially if this kind of drip measure is used.