Conceptual and geographical shifts in minimally invasive neurosurgery: a bibliometric perspective

The “keyhole approach” in minimally invasive neurosurgery (MINS) utilizes precise anatomical corridors to access intracranial targets with minimal collateral footprint. This study performs a bibliometric analysis to elucidate the field’s evolutionary trends, hotspot shifts, and research gaps over the past two decades. Literature explicitly indexed under the keyhole concept from 2003 to 2025 was retrieved from the Web of Science Core Collection (WoSCC) using a focused topic search strategy. VOSviewer, CiteSpace, and Bibliometrix were utilized to visualize spatial-temporal networks, author influence, and thematic clusters. A total of 590 articles exhibited a robust upward trajectory. The USA dominates in output and impact, while China ranks second, showing emerging stewardship through high corresponding authorships (e.g., Qing Lan). World Neurosurgery is the most prolific journal. Crucially, keyword evolution signifies a paradigm shift from a “vascular/eyebrow” era to an “oncological/endonasal” era. Thematic clustering confirms a “target-centric” maturation where surgical modalities are inextricably tethered to pathologies, distinguishing established supratentorial corridors from the nascent, isolated transorbital frontier. Over the past 20 years, the keyhole concept has metamorphosed from an “access-centric” technique to a “target-centric” neuro-oncological pillar, driven by the fusion of endoscopy and neuronavigation. Future research must bridge the identified “bibliometric void” by prioritizing digital augmentation (robotics, AR) and functional validation to maximize patient quality of life. The field has undergone a robust trajectory, transitioning from an “experimental novelty” to a “standardized neurosurgical pillar” over the last two decades. While the United States maintains structural hegemony and technological capitalization, a significant geopolitical shift has occurred post-2022, with research hotspots migrating toward developing nations such as Turkey and India. This dispersion signals the “global democratization” of MINS, implying that the steep learning curve has flattened sufficiently to allow integration into resource-constrained healthcare systems. The literature reveals a fundamental logical shift from an “Access-Centric” paradigm—defined by where the incision is made (e.g., “eyebrow incision”)—to a “Target-Centric” paradigm focused on disease management (e.g., “tumor resection”). Technical innovation is no longer occurring in a vacuum but is now strictly dictated by specific pathological requirements. This suggests that the novelty of the approach itself has yielded to a pragmatic focus on clinical outcomes. There has been a distinct metamorphosis in clinical indications, moving from a “Vascular Era”—which prioritized the feasibility of aneurysm clipping through limited corridors—to an “Oncological Era”. This is evidenced by the dominance of clusters related to meningiomas and tumor management. The integration of the endoscope has fundamentally altered the scope of treatable pathologies, allowing surgeons to shift their focus from the convexity to the complex ventral skull base. The conceptual coalescence of the Endoscopic Endonasal Approach (EEA) with traditional transcranial keyhole microsurgery has broken down traditional sub-specialty silos. This evolution points toward the emergence of the “Corridor-Agnostic” surgeon, for whom the choice between open, keyhole, or endonasal approaches is strategic rather than dogmatic. In this modern framework, the optimal minimal-access route is tailored strictly to the lesion’s geometry. Despite advances in anatomical feasibility, the analysis identifies a conspicuous “bibliometric void” regarding robotics, augmented reality (AR), and automated segmentation. The current research landscape remains focused on physical technique rather than digital augmentation. Consequently, the next epoch of innovation must pivot from “how to reach the target” to enhancing surgical perception via AR and validating functional outcomes.