Glaucoma

Neovascular Glaucoma

Tufts of neovascularization at the peripupillary margin.
  • Usually predisposed by hypoxia or ischemic state of the tissue.
  • Most common predisposing conditions include diabetic retinopathy and central retinal vein occlusion.
  • Other causative factors include retinal detachment and other retinal ischemic diseases.

Clinical Features

  • Early detection of rubeosis is usually around the region of the pupillary margin and is best performed with an undilated pupil. However, it maybe difficult to detect the new iris vessels in a darkly pigmented iris.
  • New fibrovascular tissue proliferation onto the chamber angle may compromise the aqueous outflow and result in increased IOP.
  • When the proliferation becomes more extensive, peripheral anterior synechiae may occur with resultant secondary angle-closure glaucoma.
  • Peripheral anterior synechiae may further cause a radial traction along the surface of the iris and pull the pigment layer around the iris pupillary margin anteriorly (ectropion uveae).

Work Up

  • Gonioscopic examination is of great clinical importance to detect potential early angle vessel proliferation (prior to the development of iris neovascularization).
  • Iris or angle angiography and ERG may be useful to identify early anterior segment neovascularization and peripheral retinal ischemia prior to their obvious clinical presentation.

Management

  • Treatment of the underlying disease and control of IOP.
  • Prophylactic panretinal photocoagulation (PRP) in eyes with proliferative diabetic retinopathy or ischemic central retinal vein occlusion with new onset rubeosis.
  • Medical therapy with topical ß-adrenergic antagonists, a-2 agonists, and topical or oral carbonic inhibitors are beneficial in lowering the IOP.
  • Intraocular inflammation may be treated with topical corticosteroids.
  • Pilocarpine and phospholine iodide are contraindicated because they may increase inflammation, cause miosis, and worsen synechial angle closure.
  • Glaucoma surgery such as aqueous tube shunt surgery, cyclodestruction, or antimetabolite-enhanced filtration surgery is indicated to optimally control IOP if medical therapy has proven to be inadequate.
  • For blind painful eyes with uncontrollable IOP, options include continued medical therapy, cyclodestruction, retrobulbar alcohol injection, or enucleation.