Eye
Glaucoma
Primary glaucoma

Author: Nat Pernick, M.D. (see Authors page)

Revised: 8 May 2018, last major update February 2014

Copyright: (c) 2004-2018, PathologyOutlines.com, Inc.

PubMed Search: Primary glaucoma [title] pathology

Cite this page: Pernick, N. Glaucoma: primary glaucoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/eyeglaucomaprimary.html. Accessed October 17th, 2018.
Definition / general
  • Primary means no known antecedent disease
  • Either open angle (chronic simple) or angle closure type
  • Angle refers to angle of anterior chamber formed by junction of uveal tract with corneoscleral coat, an important site of aqueous drainage
Primary open angle glaucoma
  • Most common form of glaucoma
  • Due to degenerative changes in trabecular meshwork and connective tissue of Schlemm canal
  • Insidious process, usually does not produce pain or require enucleation
  • Some patients have mutations in trabecular meshwork inducible glucocorticoid response gene (TIGR, GLC1A) which produces myocilin, found in trabecular meshwork, other anterior segment tissue and optic nerve
Primary angle closure glaucoma
  • Due to anatomic or physiologic abnormalities of tissue and anterior chamber that predispose to blockage of outflow channels by iris root, often in patients with hyperopia
  • Increased posterior chamber pressure also bows iris forward and occludes trabecular meshwork
  • Increased pressure on lens damages its epithelium with minute anterior subcapsular opacities (glaukomflecken)
  • Multiple attacks may cause extensive anterior synechia and pain and lead to enucleation
Trabeculectomy
  • Excision of 1 mm or smaller fragment of trabecular meshwork to enhance drainage of aqueous from eye
  • Must embed specimen in paraffin using dissecting microscope