Dr. Grossman’s Blog

Scientists have determined that glaucoma patients who have damage to both hemifields (half of the visual field) of their eye will experience more rapid progression of the disease than patients who have damage to a single hemifield.

The study, published in the September 2009 journal Archives of Ophthalmology, reviews data from 205 patients.  79 were found with an initial superior defect, 61 with an initial inferior defect, and 65 with both hemifields affected.  

Analysis showed significantly higher baseline intraocular pressure and thinner central corneal thickness in patients with initial damage to both hemifields.

The study authors concluded that initial damage to both hemifields increases the risk of glaucoma progression, and that doctors should consider more aggressive therapy for these patients.

Learn more about glaucoma, including natural ways to help prevent and care for glaucoma at the Natural Eye Care website

SOURCE:  Glaucoma With Early Visual Field Loss Affecting Both Hemifields and the Risk of Disease Progression, De Moraes, et al,  Arch Ophthalmol. 2009;127(9):1129-1134.

A study by Alcon Research Ltd. and the University of Iowa suggests that increased expression of the protein sFRP-1, an inhibitor of cell signaling through WNT proteins, may be responsible for elevated IOP in individuals with glaucoma.

Glaucoma is a major cause of visual impairment and blindness throughout the world. An important risk factor for the disease is an increase in the intraocular pressure (IOP). IOP, the fluid pressure in the eye, is determined by the rate of production of the clear fluid in the eye and the rate at which this fluid flows out of the eye. Although it is thought that impaired outflow of fluid from the eye causes the increased IOP in individuals with glaucoma, the exact molecular mechanisms of the disease are not fully understood.

Researchers found increased expression of sFRP-1 in eye tissue from patients with glaucoma; when they treated donor human eyes with sFRP-1 ex vivo, these eye tissues had less outflow of fluids compared to untreated eyes. The sFRP-1-treated donor eyes also had reduced expression of a WNT-related protein.

To further support this relationship, mice manipulated to express sFRP-1 in the eye displayed increased IOP. When a downstream suppressor of WNT signaling was inhibited, the problem was resolved.

The authors believe that restoring WNT signaling might provide a new method for treating patients with glaucoma in the future.

Read more about glaucoma, including information on lifestyle choices and nutrition for maintaining healthy vision.

SOURCE: “Increased expression of the WNT antagonist sFRP-1 in glaucoma elevates intraocular pressure”, Wang, et al, Journal of Clinical Investigation, 118(3): 1056-1064 (2008).