Unveiling the silent link: Normal-tension glaucoma's enigmatic bond with cardiac blood flow

Abstract

This comprehensive review embarks on a captivating journey into the complex relationship between cardiology and normal-tension glaucoma (NTG), a condition that continues to baffle clinicians and researchers alike. NTG, characterized by optic nerve damage and visual field loss despite normal intraocular pressure, has long puzzled clinicians. One emerging perspective suggests that alterations in ocular blood flow, particularly within the optic nerve head, may play a pivotal role in its pathogenesis. While NTG shares commonalities with its high-tension counterpart, its unique pathogenesis and potential ties to cardiovascular health make it a fascinating subject of exploration. It navigates through the complex web of vascular dysregulation, blood pressure and perfusion pressure, neurovascular coupling, and oxidative stress, seeking to uncover the hidden threads that tie the heart and eyes together in NTG. This review explores into the intricate mechanisms connecting cardiovascular factors to NTG, shedding light on how cardiac dynamics can influence ocular health, particularly in cases where intraocular pressure remains within the normal range. NTG's enigmatic nature, often characterized by seemingly contradictory risk factors and clinical profiles, underscores the need for a holistic approach to patient care. Drawing parallels to cardiac health, we examine into the shared vascular terrain connecting the heart and the eyes. Cardiovascular factors, including systemic blood flow, endothelial dysfunction, and microcirculatory anomalies, may exert a profound influence on ocular perfusion, impacting the delicate balance within the optic nerve head. By elucidating the subtle clues and potential associations between cardiology and NTG, this review invites clinicians to consider a broader perspective in their evaluation and management of this elusive condition. As the understanding of these connections evolves, so too may the prospects for early diagnosis and tailored interventions, ultimately enhancing the quality of life for those living with NTG.

Keywords: Normal tension glaucoma, Vascular dysregulation, Ocular blood flow, Blood pressure, Perfusion pressure, Oxidative stress

Core Tip: Cardiovascular disease and glaucoma may appear unrelated at first glance, but recent research suggests a potential link between the two seemingly distinct health issues. This review delves into the complex interplay of vascular dysregulation, blood pressure, perfusion pressure, neurovascular coupling, and oxidative stress. Furthermore, certain medications frequently prescribed for managing cardiovascular disease and high blood pressure, such as beta-blockers, may influence blood flow to the eyes. This, in turn, could potentially increase the risk of glaucoma in some individuals. This research highlights how cardiac dynamics can impact ocular health, even when intraocular pressure remains within the normal range.