الفهرس 
• Anatomy of the anterior chamber angleOnly 14 pages are availabe for public view
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Abstract
eovascular glaucoma is a secondary glaucoma that results from growth of fibrovascular tissue over the iris surface and trabecular meshwork.
Many disorders result in the development of neovascularization of the iris and NVG. Almost all of these disorders are characterized by retinal hypoxia and retinal capillary nonperfusion, the same factors involved in the development of retinal neovascularization clinically.
Hypoxia is the stimulus for neovascularization in the eye. Vasoproliferative factors, produced by hypoxia, lead to retinal neovascularization then diffuse into the anterior segment causing rubeosis iridis.
An extremely important angiogenic factors is a substance called vascular endothelial growth factor (VEGF). Basic fibroblast growth factor (BFGF) may also play a role in retinal and anterior segment neovascularization.
Neovascular growth occurs in a wide variety of disease as ischemic central retinal vein occlusion, diabetic retinopathy, carotid artery obstructive diseases, central retinal artery occlusion, rhegmatogenous retinal detachment, radiation retinopathy, intraocular tumours and uveitis.
The clinical and histologic events that lead from a predisposing factor through rubeosis iridis to advanced neovascular glaucoma may be thought of in four stages (Prerubeosis stage - Rubeosis iridis- Open-angle glaucoma stage- Angle-closure glaucoma stage).
Several examination are used to diagnose iris neovascularization and neovascular glaucoma such as high magnification slit lamp examination, assessment of intraocular pressure, gonioscopic examination, fluorescein angiography and ophthalmoscopy.
Prophylactic treatment for NVG is to treat the ischaemic retina due to CRVO or DR by PRP if media clear, Pan retinal cryotherapy is used if media are opaque. In CAOD, prophylactic treatment may be life saving by preventing stroke.
Management of NVG is by attacking the ischemic retina by PRP or peripheral retinal cryo and the new iris vessels may directly closed by mean of photodynamic therapy. Goniophotocoagulation may be used also.
Antiangiogenesis is tried. It includes: α-interferon, squalamine and intravitreal injection of crystalline cortisone.
Intravitreal bevacizumab recently has been reported to have a beneficial short-term effect in CRVO. Bevacizumab has also proven to be an effective therapy in anterior-segment neovascularization. Marked regression of iris neovascularization and improvement of neovascular glaucoma after anterior-chamber injection of bevacizumab.
Medical treatment used either to control the pressure and quieting the eye before surgery or as a palliative measure in cases with no useful vision.
Conventional filtration with antimetabolites is indicated when there is angle closure and remaining useful vision. The first operation of choice is aqueous drainage tube shunts.
Ciliary destructive procedures such as cyclocryotherapy, cyclophotocoagulation and ultrasound therapy may be done in cases of failure of valve implants or in cases with no useful vision.
In end stage NVG retrobulbar alcohol injection or even enucleation may be done.