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Acute retinal toxicity associated with a mixture of perfluorooctane and perfluorohexyloctane: failure of another indirect cytotoxicity analysis
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  • Jose C. Pastor, Girish K. Srivastava, Ivan Fernandez-Bueno, Cristina Andrés-Iglesias, Jesús Medina, Fernando Rull, Antonio Dueñas and Rosa M. Coco
    Published on:
  • Yalcin Karakucuk, Berker Bakbak and Saban Gonul
    Published on:
  • Published on:
    Letter to Editor
    • Jose C. Pastor, Professor and Ophthalmologist Instituto Universitario de Oftalmobiología Aplicada (IOBA), Eye Institute, University of Valladolid, Valladolid, Spain
    • Other Contributors:
      • Girish K. Srivastava, Principal Investigator
      • Ivan Fernandez-Bueno, Principal Investigator
      • Cristina Andrés-Iglesias, Post doc
      • Jesús Medina, Professor
      • Fernando Rull, Professor
      • Antonio Dueñas, Professor
      • Rosa M. Coco, Professor

    We have read with great interest the e-letter from Karakucuk et al. published in BJO responding to our paper titled ‘Acute retinal toxicity associated with a mixture of perfluorooctane and perfluorohexyloctane: Failure of another indirect cytotoxicity analysis ’ and we appreciate their positive appreciation of our research work.
    We consider extraordinarily important that they have reported four more cases in their country, thus, supporting that acute toxicity cases were not a Spanish problem as has been stated by some retinologist at an European congress (Barcelona, September 2017).
    We believe that this letter should encourage other colleagues from other countries from all over the world to report cases that certainly exist, according to non-official information from several companies.
    We completely agree that the ISO (the International Organization for Standardization) guidelines to determine the in vitro cytotoxicity of intraocular medical devices should be immediately changed. These guidelines should adopt direct cytotoxicity methods to be performed with finished, sterilized, and ready for release products. The analytical method utilized should include cells or tissues close to those of the retina to guarantee specific sensitivity and should be scientifically validated.
    We support the suggestion of increasing chemical research, because some companies are promoting chemical tests, as a “safety guarantee”, whose scientific validity and their direct...

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    Conflict of Interest:
    None declared.
  • Published on:
    Letter to Editor
    • Yalcin Karakucuk, Doctor Selcuk Universitesi opthalmology Selcuk university faculty of medicine Konya
    • Other Contributors:
      • Berker Bakbak, Doctor
      • Saban Gonul, Doctor

    Dear Editor:

    We read the article ‘Acute retinal toxicity associated with a mixture of perfluorooctane and perfluorohexyloctane: Failure of another indirect cytotoxicity analysis ’ by Coco et al. with great interest.[1] In this study, the authors reported on ocular toxicity due to perfluorooctane (PFO). They advised that the protocols used to determine the cytotoxicity of intraocular medical devices (which have been approved by the Organisation for the Standardisation of International Standards based on indirect methods) should be revised to ensure safety. We congratulate Coco et al.1 for their report because we believe that it has the potential to be a significant contribut or to the literature on this topic.

    As is commonly known, PFO is saturated with PFO liquids, which have highly stable carbon-fluorine bonds that consequently make them inert. PFO has highly specific gravity, low viscosity, optical clarity immiscibility in water and interface tension towards water. It is regularly used in vitreoretinal surgery for complex retinal detachment repair because it displaces subretinal fluid and blood anteriorly, unfolds the retina in giant retinal tear cases and provides counter traction and retinal stabilisation during membrane peeling in eyes with proliferative vitreoretinopathy.[2,3] These properties make PFO useful for intraocular surgery. However, some limitations exist regarding PFO use as a long- term tamponade such as amaurosis, a lack of light perce...

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    Conflict of Interest:
    None declared.