Drug Delivery Research Related to Posterior Segment Eye Diseases: A Bibliometric Analysis of Global Trends and Therapeutic Hotspots.

PURPOSE: Drug delivery to the posterior segment remains constrained by ocular barriers, short intraocular residence, repeated administration, and safety concerns. We mapped the global research structure of drug delivery research related to posterior segment eye diseases and identified major contributors, knowledge foundations, and therapeutic hotspots.

METHODS

English-language articles and reviews published from 1999 to 2024 were retrieved from the Web of Science Core Collection using a predefined topic search combining drug-delivery and posterior segment terms. Bibliometrix, VOSviewer, and CiteSpace were used to analyze publication growth, contributors, journals, highly cited articles, cocited references, keyword co-occurrence, citation bursts, thematic evolution, and conceptual structure.

RESULTS

The dataset contained 4,055 publications and showed sustained growth, with a higher output phase after 2020. The United States and China were the leading national contributors, while the University of Helsinki, University of Eastern Finland, Johns Hopkins University, and Emory University were prominent institutional contributors. Keyword, burst, and thematic analyses indicated a shift from permeability, pharmacokinetics, and sustained-release platforms toward macular degeneration, anti-VEGF-related therapy, injection burden, nanoparticles, long-acting systems, and clinically oriented formulation strategies.

CONCLUSION

Research has shifted from barrier characterization, pharmacokinetics, and sustained-release platforms toward macular degeneration, anti-VEGF-related therapy, injection burden, long-acting systems, and clinically oriented formulation strategies. These bibliometric signals indicate research activity rather than clinical effectiveness.