Retinal Toxicity of Medical Devices Used during Vitreoretinal Surgery: A Critical Overview

Abstract

Retinal toxicity/biocompatibility of medical devices in direct contact with the retina is an important subject for clinicians and scientists. As these effects are not very frequent, there is also a relative lack of information for many clinicians. The past has taught us multiple times that there is a significant safety problem associated with severe loss of vision in affected patients. In this review, we want to classify medical products that are used in the back of the eye, describe recent examples of toxicity, critically reflect on the regulations that exist and suggest improvements that can be done to ensure patient safety without hindering innovation. Methods: Critical review of the recent papers and personal experience of the authors in this issue. Medical devices used in the back of the eye and recent examples of toxicity are described, regulations that exist are critically reflected and improvements suggested that can ensure patient safety without hindering innovation. Results: There is clear evidence of toxicity after intraocular surgery in any category. Some cytotoxic indirect methods have failed in detecting this toxicity. Some ISO rules do not seem appropriate. Postmarketing safety is missing. There is little data on this issue. Conclusions: The absence of a clear regulation of the production, purification and evaluation of the toxic effects of the medical devices supposes the possibility that products are not sufficiently safe to obtain the CE mark.

Metal–Organic Frameworks as Drug Delivery Platforms for Ocular Therapeutics

“…suggest that cell lines derived from retinal cells such 661W or ARPE19 cells are the most accurate to evaluate retinal toxicity. 45 Thus, cytotoxicity of MOFs and their components was assessed in 661W cells (Figure 4). As it can be appreciated in Figure 4, except in the specific case of HKUST-1, the cell viability evaluated after 48h exposure is, in all cases, very close to Interestingly, these numbers are a priori within the theoretical threshold that human eye can hold.…”

Hydrofluoric Acid and Other Impurities in Toxic Perfluorooctane Batches

“…The damaging mechanisms, such as inhibition of the enzymatic system by HF, its long-lasting penetration into deeper tissue layers, and damage along vascular and neuronal structures seem to be of particular interest in view of the symptoms of retinal toxicity reported after the use of contaminated PFO batches 23. The progressive damage, long-lasting corrosiveness, terrible healing potential, and severe necrosis associated with HF burns reveal remarkable parallels to the ocular damage that has been observed 22,23…”

New Brilliant Blue G Derivative as Pharmacological Tool in Retinal Surgery

“…The ILM removal has been introduced as adjuvant surgical procedure to improve anatomic and functional outcomes during surgery for macular hole (Lois et al, 2011) and epiretinal membrane (Schechet et al, 2017). Vital dyes for the ILM staining are commonly used in vitreoretinal surgery as ultrashort-acting pharmacological tools, that are used once or more times during the surgery, and then removed few seconds after administration (Januschowski et al, 2018). Despite the widespread use of these molecules in retinal surgery, unmet medical needs still remain unsolved, such as selectivity for ILM and safety.…”