<i>In vivo</i> confocal microscopy in ophthalmology: research trends from a bibliometric analysis

In vivo confocal microscopy (IVCM) is a pivotal imaging tool in ophthalmology, enabling the non-invasive, real-time visualisation of corneal microstructures. Its clinical importance lies in its ability to diagnose and monitor a wide range of corneal and ocular surface conditions at a cellular level, enhancing early detection and treatment outcomes. IVCM enables detailed visualisation of corneal structures and has broad applications in diagnosing and managing corneal and ocular surface diseases. Despite its widespread use, no global bibliometric analysis of IVCM research in ophthalmology has been conducted to date. This study aims to bridge this gap by identifying influential articles, authors, institutions, and emerging trends in IVCM research. A bibliometric analysis was conducted using the Web of Science Core Collection database. Articles and reviews in the ophthalmology research area were identified by searching for ‘confocal microscopy’ within titles and author keywords. Sub-analyses focused on corneal nerves and immune cells. Data were visualised using VOSviewer to create overlay visualisation maps, highlighting research trends and connections. A total of 1,389 articles were identified, with 600 published in the last decade. Corneal nerve studies constituted 425 publications, with an h-index of 68 and 38.81 citations per article. Immune cell studies accounted for 182 publications, with an h-index of 36 and 25.79 citations per article. The United States, China, and Italy were the most productive countries, while Harvard Medical School and the Massachusetts Eye and Ear Department of Ophthalmology led institutional output. Emerging keywords included ‘limbal stem cell deficiency’, ‘deep learning’, and ‘artificial intelligence’. This study underscores the increasing impact and versatility of IVCM in ophthalmology. The findings highlight key contributors and trends, providing a roadmap for future research. The integration of artificial intelligence and novel analytical techniques will likely drive further advancements, enhancing the diagnostic and therapeutic potential of IVCM.