A series of recent acute blindness cases following non–complicated retinal detachment surgery caused the release of several health alerts in Spain. The blindness was attributed to certain lots of perfluoro-octane (PFO; a volatile and transient medical device). Similar cases have been reported in other countries. This has raised questions regarding the validity of cytotoxicity test methods currently used to certify the safety of PFO lots. The tests were performed according to the International Organization for Standardization (ISO) norms, using the extract dilution method or the indirect contact method as applied to L929 cells, a line derived from mouse fibroblasts. The limitations of those methods have been resolved in this study by proposing a new cytotoxicity test method for volatile substances. The new method requires direct contact of the tested substance with cells that are similar to those exposed to the substance in the clinical setting. This approach includes a few new technical steps that are crucial for detecting cytotoxicity. Our new method detected toxic PFO lots that corresponded to the lots producing clinical blindness, which previous methods failed to detect. The study suggests applying this new method to avoid occurrence of such cases of blindness.

Aims: To compare anatomical and functional outcomes for 546 phakic and pseudophakic primary rhegmatogenous retinal detachments (RDs) treated by pars plana vitrectomy or scleral buckling. Methods: Prospective, non-randomised, interventional study in 15 centres in Spain and Portugal, with data from RDs consecutively treated from January 2005 to May 2007. Cases with preoperative proliferative vitreoretinopathy grade C-1 or higher and perforating trauma were excluded. Minimum follow-up was 3 months. Twenty-seven pre-, intra- and post-surgical variables for each patient were analysed. Multivariate analysis was carried out by logistic regression analysis with stepwise selection of variables. Results: Data from 546 patients were analysed. Global anatomical success was 94.7%. Logistic regression analysis showed that only the development of postoperative proliferative vitreoretinopathy was associated with a poor anatomical outcome. The poorest functional results were associated with macular involvement, extension of RD, previous RD surgery, time of evolution of RD, and age of patient. Hierarchical log-linear analysis showed no effect of the lens status (phakic versus pseudophakic) on the functional results. However, pars plana vitrectomy was most often performed in pseudophakic eyes and resulted in a worse final visual acuity (p<0.001). Conclusions: No differences in anatomical success between phakic and pseudophakic eyes were found in this series. Pars plana vitrectomy was most often performed in pseudophakic eyes and had a greater probability of a worse final visual acuity than scleral buckling.