Method and Apparatus to Identify and Treat Neovascular Membranes in the Eye
Associated with a number of pathological conditions is the growth of ocular neovascular membranes. These membranes are often in close proximity to the sensory retina of the eye. If the abnormality arises from the retinal vessels, it is called a retinal neovascularization. If it is from the choroidal vessels, it is called a choroidal neovascularization (CNV). Both kinds of neovascularizations can diminish vision: in the case of retinal neovascularization by blocking light focused by the eye's lens into the retina, and in the case of CNV by distorting the ordinarily flat sensing retina. CNV is particularly difficult to identify and treat, especially when it lies beneath the retinal pigment epithelium or RPE, a layer of pigmented cells between the retina and the choroid since the RPE does not readily transmit visible light ordinarily used to examine the retina.
The method and apparatus of the invention allow a neovascular membrane in the ocular vasculature of the fundus of the eye to be identified and treated while minimizing damage to the sensory retina. First, a bolus of fluorescent dye is injected and allowed to circulate through the ocular vasculature. When the fundus is diffusely irradiated with laser energy, dye present in the vasculature fluoresces. A neovascular membrane is identified when a particular area of fluorescence differs from the fluorescence of the surrounding normal vasculature. To treat the neovascular membrane, a second laser is focused on the site of the membrane and a second bolus of fluorescent dye is injected. When the presence of the second injection of dye is detected, energy from the focused laser is applied to damage or destroy the neovascular membrane.
Patent Status: U.S. patent(s) 5,279,298 issued. International patents issued.
Mr. E. Chalfin
Phone: (443) 778-7473