New Method Gives Glaucoma Researchers Control Over Eye Pressure: Study

Pressure in the eye is enough to cause and explain glaucoma. This has been the conclusion of a new study following the development of a method that permits continuous regulation of pressure without damaging the eye. The findings of the study are published in the journal Scientific Reports.

Researchers were able to manipulate pressure by implanting a tiny tube in the eye of an animal model and connecting the tube to a pressure source and pressure sensor. The pressure source infused fluid into the eye via a saline reservoir or a portable micropump built by the researchers. The pressure sensor took measurements every few seconds around-the-clock for up to two months, during which time the tube remained fixed in place even though the eye blinked and rotated, and the animal freely moved.

‘A glaucoma is a heterogeneous group of ocular disorders characterized by progressive and preferential loss of retinal ganglion cells (RGCs), resulting in visual field deficits and, ultimately, blindness. ’

The study found that raising the pressure of an otherwise healthy eye resulted in patterns of the retina and optic nerve damage like that seen in human glaucoma.

"The technique offers a significant advancement in glaucoma research," said Chris Passaglia, Ph.D., professor of medical engineering at USF. "All studies to date have elevated pressure by blocking fluid outflow from the eye, whereas ours adds fluid as necessary to produce the desired pressure without damaging outflow pathways. Now researchers can have direct knowledge and control of eye pressure."

A longstanding challenge with existing methods of glaucoma induction is that eye pressure changes are unpredictable and generally irreversible. Pressure may rise to unrealistic levels or not change at all if induction procedures are unsuccessful. Pressure can also settle at a stable value, fluctuate irregularly over time, or return abruptly to normal. Passaglia says the new tools can help speed research progress by removing such experimental variability and by enabling systematic studies of unanswered questions like the role of eye pressure history in disease onset and progression. Putative glaucoma drugs can also be concurrently infused by the system into the eye of animal models and screened for therapeutic effectiveness.

Source: Eurekalert