H-Content Is Not Predictive of Perfluorocarbon Ocular Endotamponade Cytotoxicity in Vitro

Abstract

In recent years, cases of retinal toxicity occurred in some European, Middle Eastern, and South American countries following the use of perfluorocarbon liquids (PFCLs) on vitreoretinal surgeries owing to impurities in the product. Moreover, Spanish ophthalmologists reported several toxic cases on the use of perfluoro- n -octane Ala Octa (Alamedics, Dornstadt, Germany), raising the necessity of reviewing the current validated methods used for assessing the safety of PFCLs. We proved that in samples of PFCLs contaminated on purpose with impurities previously detected in Ala Octa devices, the determination of the so-called H-content using a 1 H NMR quantitative assay implemented with the electronic reference to access in vivo concentrations 2 technology failed to demonstrate a correlation between the H-content and in vitro cytotoxicity test in ARPE-19 and BALB 3T3 cell lines. Therefore, direct information on the safety of PFCLs was provided only by the cytotoxicity test in vitro validated according to ISO 10993-5, and the H-content was not predictive of perfluorocarbon ocular endotamponade cytotoxicity in vitro.

Toxicity Threshold of Perfluorocarbon Liquids for Intraocular Use: Dose–Response Assessment of In Vitro Cytotoxicity of Possible Contaminants

“…The findings in this study are in agreement with the results obtained by Ruzza et al, 18 who studied the extent of ARPE-19 and BALB3T3 cell mortality after the application of 1H-PFO, PFOA, and 5H-PFO at three of the concentrations tested in this study and Romano et al's. 15 The toxicity threshold assessed for PFOA and DFH in this study only slightly differed from those evaluated by Srivastava et al, 17 who found that PFOA at 0.06 mM was close to the toxicity limit, which corresponded to 25 ppm versus CC 30 of 17 ppm determined in our study, and DFH was toxic at 4.48 mM (corresponding to 1488 ppm vs. 1173 ppm in our study).…”

“…The risk of presence or appearance of potentially toxic substances in PFCL-based medical devices used as vitreous tamponades needs to be excluded by the manufacturers using accurate analytical methods and adequate safety criteria for their clinical use. 6 - 8 , 11 , 18 , 21 …”

“…The ISO 10993-5 reference cell line, murine fibroblast cells BALB3T3 clone A31 (ATCC CCL163), and the human retinal pigment epithelial cell line ARPE-19 (ATCC CRL-2302) were obtained from the American Tissue Culture Collection (ATCC, Manassas, VA, USA) and used as previously described. 15 , 18 In particular, after thawing, BALB3T3 and ARPE-19 cells were grown as a monolayer in Dulbecco's modified Eagle medium (DMEM) with high glucose, L-glutamine, sodium pyruvate, and sodium bicarbonate (Sigma-Aldrich Corp) and Dulbecco's modified Eagle medium/Nutrient Mixture F-12 medium with L-glutamine without 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES; Gibco, Waltham, MA, USA), respectively, each supplemented with 10% of newborn calf serum (Sigma-Aldrich Corp) and 1% penicillin–streptomycin (Sigma-Aldrich Corp), in 75 cm 2 culture flasks in an incubator (Memmert, Schwabach, Germany) at 37°C ± 1°C, 90% ± 10% humidity, 5.0% ± 1.0% CO 2 /air. The cultures were used after two passages.…”

Intraocular toxicity caused by MEROCTANE perfluorocarbon liquid

“…These, and other examples with other medical devices for intraocular use, have resulted in our insistence that, in addition to chemical analyses ensuring an acceptable degree of purity, companies should be forced to carry out cytotoxicity studies on each batch. Toxicity, in our opinion, is not a simple matter related to the percentage of purity (obviously, the purer the better) but mainly to the nature of the contaminants, which, depending on the compound, can be highly cytotoxic even at very low concentrations; this has been demonstrated for acids or side products from manufacturing as in the case of BIO OCTANE PLUS 2,6 . Table 2 summarizes information on reported toxicity cases of PFO from the three different manufacturers, Meran, AlaMedics and Biotech.…”

The Safety of Medical Devices Used During Intraocular Surgery

“…Although it may be a desirable kind of index, a direct relationship between H index and toxicity has not yet been demonstrated. 14,15 Some companies seem to find it difficult to accept that there have been hundreds, probably thousands, of cases of blindness with these products (e.g. from toxic batches of AlaOcta ® more than 1,000 samples were distributed in Spain alone, although there is information only on 117 officially affected cases), and that a close collaboration between industry and clinicians is of paramount importance.…”