Secondary Open Angle Glaucoma

 Secondary Open Angle Glaucoma

Definition

 

The anatomic relationships between the root of the iris, the trabecular mesh-work, and peripheral cornea are not disturbed. However, the trabecular mesh-work is congested and the resistance to drainage is increased.

The most important forms: 

Pseudoexfoliative glaucoma. This form occursparticularly frequently in Scandinavian countries. Deposits of amorphous acellular material form throughout the anterior chamber and congest the trabecular meshwork.

Pigmentary glaucoma. Young myopic men typically are affected. The dis-order is characterized by release of pigment granules from the pigmentary epithelium of the iris that congest the trabecular meshwork.

Cortisone glaucoma. Thirty-five to forty per cent of the population react tothree-week topical or systemic steroid therapy with elevated intraocular pressure. Increased deposits of mucopolysaccharides in the trabecular mesh-work presumably increase resistance to outflow; this is reversible when the steroids are discontinued.

Inflammatory glaucoma. Two mechanismscontribute to the increase inintraocular pressure:

1.        The viscosity of the aqueous humor increases as a result of the influx of pro-tein from inflamed iris vessels.

2.        The trabecular meshwork becomes congested with inflammatory cells and cellular debris.

Phacolytic glaucoma.This is acute glaucoma in eyes with mature or hyper-mature cataracts. Denatured lens protein passes through the intact lens cap-sule into the anterior chamber and is phagocytized. The trabecular meshwork becomes congested with protein-binding macrophages and the protein itself.

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