Mapping Half a Century of Global Brain Abscess Research: A Bibliometric Analysis of Output, Themes, and Collaboration (1975–2025)

Abstract

Brain abscess is an uncommon but life-threatening intracranial infection managed across neurosurgery, infectious diseases, microbiology and neuroradiology, for which no single unified international guideline exists; despite a large literature, the research field has been mapped only once, in a single-database study of 994 title-matched records. We performed a comprehensive bibliometric analysis of global brain-abscess research, retrieving journal articles (1975-2025) from the OpenAlex database using an exact-phrase title/abstract search and computing performance metrics, bibliometric laws and science mapping in R. Across 9,097 articles (35,138 authors; mean 4.5 authors per article; 12.6% single-authored), annual output grew at 4.07% per year (95% CI 3.78-4.36; quasi-Poisson regression), a doubling time of 17.4 years, with the 2020-2025 window already approaching the entire 2010s; this rate is statistically indistinguishable from the growth of the scientific literature as a whole, and the field’s share of world output fell between 1975 and 2015 before recovering after 2020. Output was led by the USA, India, Japan, China and the UK, with modest international co-authorship (7.2%), and publications spanned neurosurgical, infectious-disease, paediatric and microbiological journals. Themes shifted from computed tomography toward magnetic resonance imaging, retained a persistent microbiology-antibiotics-meningitis core, and showed the recent emergence of cardiology-related themes consistent with the endocarditis and cyanotic-congenital-heart-disease associations; author productivity was highly dispersed (88.8% single-paper authors), open access rose to 75% of recent output, only 6% of articles recorded funding, and Indian institutions led productivity. All metrics were regenerated from an archived copy of the dataset rather than the live database, which is continuously updated; relevance was validated by independent dual screening of a random sample (Cohen’s kappa = 0.95), and findings were robust in a title-only sensitivity analysis and cross-validated across three bibliographic databases. Brain-abscess research is sustained, distributed across venue types and internationally, with substantial output from institutions in lower- and middle-income settings. These findings describe publication patterns rather than research quality or clinical impact, derive principally from a single database, and identify questions for future work rather than recommendations for practice.