Newly identified lymphatic network could fundamentally shift how we understand and treat leading causes of blindness.
Researchers at the University of British Columbia and the University of Toronto have discovered a previously unknown waste-drainage system at the back of the eye, a finding that could reshape how scientists understand — and eventually treat — some of the leading causes of blindness.
The newly mapped pathway, called the posterior ocular lymphatic outflow (POLO) pathway, allows fluid and waste to exit the eye and drain into the body’s broader lymphatic system. The discovery adds a missing piece to the puzzle of how the eye clears debris, a process whose breakdown is linked to conditions such as age-related macular degeneration, which affects an estimated 2.5 million Canadians.
“This changes how we think about the eye’s relationship to the rest of the body,” said Dr. Neeru Gupta, professor and head of ophthalmology and visual sciences at UBC.
In 2009, Gupta and Dr. Yeni Yücel, professor and director of ophthalmic pathology at the University of Toronto and a pathologist-scientist at St. Michael’s Hospital, discovered a similar “uveolymphatic” pathway at the front of the eye. The new study extends that work to the back of the eye, mapping lymphatic vessels within the choroid — the vascular layer beneath the retina — that drain into orbital tissue and nearby lymph nodes within minutes.
“Finding a lymphatic drainage system in the back of the eye gives us a new way to think about diseases we’ve struggled to treat for decades,” said Yücel.
The team used MRI, near-infrared fluorescence imaging, microscopic analysis, and fluorescent tracers in mice to trace the pathway and confirm that it functions as an active drainage route rather than a passive structural feature.
Journal: Translational Vision Science & Technology
DOI: 10.1167/tvst.15.7.23
Article Title: Identification and Mapping of a Posterior Ocular Lymphatic Outflow (POLO) Pathway Through Choroidal Lymphatics
Publication Date: 17-Jul-2026
Source: EurekAlert