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Comparison between direct contact and extract exposure methods for PFO cytotoxicity evaluation.
Girish K Srivastava1,2,3, Maria L Alonso-Alonso4, Ivan Fernandez-Bueno4,5,6
1Instituto Universitario de Oftalmobiologia Aplicada (IOBA), Universidad de Valladolid, Valladolid, Spain. girish@ioba.med.uva.es.
Scientific Reports
|January 25, 2018
Summary
New cytotoxicity tests accurately detect toxic perfluoro-octane (PFO) lots linked to blindness after eye surgery. This method ensures patient safety by identifying harmful PFO batches missed by older tests.
Area of Science:
- Ophthalmology
- Biomaterials Science
- Toxicology
Background:
- Acute blindness cases post-retinal detachment surgery linked to perfluoro-octane (PFO).
- Existing cytotoxicity tests (ISO norms, extract dilution, indirect contact) failed to identify toxic PFO lots.
- International health alerts issued due to PFO-related blindness.
Purpose of the Study:
- To develop a novel cytotoxicity test method for volatile substances like PFO.
- To address limitations of current methods in detecting PFO toxicity.
- To improve the safety certification of medical devices used in ophthalmology.
Main Methods:
- Proposed a new cytotoxicity test requiring direct contact with relevant cells.
- Incorporated specific technical steps crucial for detecting cytotoxicity of volatile substances.
- Utilized cell lines similar to those exposed clinically to PFO.
Main Results:
- The new method successfully detected toxic PFO lots.
- Identified PFO lots that correlated with reported clinical blindness cases.
- Demonstrated superior sensitivity compared to existing ISO-standard methods.
Conclusions:
- The developed direct contact cytotoxicity test is effective for volatile substances.
- Implementing this new method can prevent blindness associated with PFO use.
- Revising PFO safety testing protocols is recommended to enhance patient safety.
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