Coring of Intravitreal Medication Vial Stoppers: A Report From the Research and Safety in Therapeutics Committee of the American Society of Retina Specialists

In 2024, the American Society of Retina Specialists (ASRS) Research and Safety in Therapeutics (ReST) Committee became aware of reports of coring of vial stoppers in relation to preparation of intravitreal injections. A literature review was performed to further understand and characterize this occurrence within the context of retina practice and the broader medical community. Relevant articles were identified through a systematic search of PubMed using predefined criteria. Coring can be observed when a needle punctures the rubber stopper of a medication vial, pushing a small piece or pieces of the stopper material into the container and introducing extrinsic particles into the drug product. Factors associated with coring include larger gauge needles, perpendicular needle entry, multiple-use vials, and thicker rubber stoppers. Rubber stopper thickness and composition also influence the likelihood of coring. To prevent patient safety issues from coring, filter needles are commonly used to draw up medications from vials because they are effective in mitigating particulate matter from entering syringes. No documented cases of clinical complications related to coring in ophthalmology have been identified. Coring represents an unreported phenomenon in the preparation of intraocular medications. Although there have been no safety implications in retina practice related to coring and intravitreal drug vials, these reports underscore the importance of careful medication preparation, inspection of vials, the use of appropriate needles, and adherence to best clinical practices.