Ophthalmology Book

http://www.fpnotebook.com/

Glaucoma

Aka: Glaucoma
Advertisement
  1. See Also
    1. Open Angle Glaucoma
    2. Narrow Angle Glaucoma
  2. Definition
    1. Increased Intraocular Pressure with Optic Nerve injury
  3. Epidemiology
    1. Within top 3 causes of blindness in U.S.
      1. Leading cause of blindness in non-white
    2. Prevalence: 2 Million in United States
      1. Only 50% are estimated to now be under treatment
      2. 120,000 are blind due to Glaucoma
  4. Pathophysiology
    1. Elevated Intraocular Pressure (IOP)
      1. Increased production of Aqueous Humor by ciliary body
      2. Increased outflow resistance at Aqueous Outflow Angle
        1. Trabecular meshwork
        2. Canal of Schlemm
    2. Progressive changes in optic disc
      1. Nerve damage related to increased IOP is variable
        1. Glaucoma suspects (66% of those with high IOP)
          1. No damage despite high Intraocular Pressure (>21)
          2. Optic Nerve injury rate in suspects: 1% per year
        2. Normal-pressure Glaucoma (15% of Glaucoma patients)
          1. Normal Intraocular Pressure (21 mmHg or less)
          2. Glaucoma-related Optic Nerve damage
      2. Progressive Glaucomatous cupping at the optic disc
        1. IOP collapses Optic Nerve head structural support
        2. Axons destroyed by mechanical compression
    3. Peripheral visual field loss
      1. Open Angle Glaucoma: Slowly progressive
      2. Narrow Angle Glaucoma: Rapid Vision Loss
  5. Types
    1. Primary Glaucoma
      1. Open Angle Glaucoma (89%)
        1. Outflow blocked by microscopic outflow changes
        2. Results in progressive peripheral Vision Loss
        3. Usually asymptomatic until 40% of nerve loss
      2. Narrow Angle Glaucoma
        1. Outflow tract blocked by base of iris
        2. Permanent Vision Loss may occur in hours
        3. Presents as acute painful red eye with Vomiting
    2. Secondary Glaucoma
      1. Medications that increase IOP in those predisposed
        1. Corticosteroids (Systemic and Topical)
          1. Reversible
        2. Mild Adrenergic or Anticholinergic Medications
          1. Examples
            1. Cold Medications
            2. Antidepressants
            3. Antidiarrheals
          2. Effect: Dilate Pupil
            1. Theoretically worsen angle closure Glaucoma
            2. Not contraindicated in Glaucoma
  6. Resources
    1. Aging Eye Glaucomatrac (Glaucoma Management Tracking)
      1. http://www.agingeye.net/glaucomacharting.index
    2. Aging Eye Glaucoma Video
      1. http://www.agingeye.net/mainnews/video.php
    3. Glaucoma Foundation
      1. http://www.glaucoma-foundation.org
      2. Phone: 1-800-Glaucoma
  7. References
    1. Alward (1998) N Engl J Med 339:1298-307
    2. Distelhorst (2003) Am Fam Physician 67(9):1937-50
    3. Infeld (1998) Postgrad Med 74:709-15

Glaucoma (C0017601)

Definition (NCI) A disorder characterized by an increase in pressure in the eyeball due to obstruction of the aqueous humor outflow.
Definition (MEDLINEPLUS)

Glaucoma damages the eye's optic nerve. It is a leading cause of blindness in the United States. It usually happens when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Often there are no symptoms at first, but a comprehensive eye exam can detect it.

People at risk should get eye exams at least every two years. They include

  • African Americans over age 40
  • People over age 60, especially Mexican Americans
  • People with a family history of glaucoma

Early treatment can help protect your eyes against vision loss. Treatments usually include prescription eyedrops and/or surgery.

NIH: National Eye Institute
Definition (NCI) A condition in which there is a build-up of fluid in the eye, which presses on the retina and the optic nerve. The retina is the layer of nerve tissue inside the eye that senses light and sends images along the optic nerve to the brain. Glaucoma can damage the optic nerve and cause loss of vision or blindness.
Definition (MSH) An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
Definition (NCI) Increased pressure in the eyeball due to obstruction of the outflow of aqueous humor.
Definition (CSP) group of diseases characterized by increased intraocular pressure resulting in damage to the optic nerve and retinal nerve fibers.
Concepts Disease or Syndrome (T047)
MSH D005901
ICD9 365.9, 365
ICD10 H40, H40-H42.9, H40.9, H40-H42
SnomedCT 155120009, 194631001, 193569008, 23986001
English Glaucoma syndrome, Glaucomas, Glaucoma, Unspecified glaucoma, GLAUCOMA, GLAUCOMAS, Glaucoma, NOS, Glaucoma NOS, Glaucoma, unspecified, glaucoma (diagnosis), A-730-733 GLAUCOMAS, glaucoma, Glaucoma NOS (disorder), Glaucoma [Disease/Finding], glaucomas, Glaucoma (H40-H42), Glaucoma (disorder)
French GLAUCOME, Glaucome SAI, Glaucome, non précisé, Glaucome non précisé, Glaucome
Portuguese GLAUCOMA, Glaucoma NE, Glaucoma
Spanish GLAUCOMA, Glaucoma no especificado, Glaucoma NEOM, Glaucoma, glaucoma (trastorno), glaucoma, SAI (trastorno), glaucoma, SAI, glaucoma
German GLAUKOM, Glaukom, unspezifisch, Glaukom NNB, unspezifisches Glaukom, Glaukom, nicht naeher bezeichnet, Glaukom, Star, grüner
Dutch glaucoom NAO, glaucoom, niet-gespecificeerd, niet-gespecificeerd glaucoom, Glaucoom, niet gespecificeerd, glaucoom, Glaucoom
Italian Glaucoma NAS, Glaucoma non specificato, Glaucoma
Japanese 緑内障ＮＯＳ, 緑内障, 詳細不明の緑内障, 緑内障、詳細不明, ｼｮｳｻｲﾌﾒｲﾉﾘｮｸﾅｲｼｮｳ, ﾘｮｸﾅｲｼｮｳNOS, ﾘｮｸﾅｲｼｮｳｼｮｳｻｲﾌﾒｲ, ﾘｮｸﾅｲｼｮｳ
Swedish Grön starr, GLAUKOM
Czech zelený zákal oční, glaukom, Glaukom, Blíže neurčený glaukom, Glaukom NOS
Finnish Glaukooma, VIHERKAIHI
Russian GLAUKOMA, ГЛАУКОМА
Norwegian GRONN STAER/GLAUKOM
Danish Glaukom
Hungarian zoldhalyog, Glaucoma k.m.n., Glaucoma, nem meghatározott, Glaucoma, Nem meghatározott glaucoma
Korean 상세불명의 녹내장, 녹내장
Croatian GLAUKOM
Basque GLAUKOMA
Hebrew glaukoma
Polish Jaskra
Sources
Derived from the NIH UMLS (Unified Medical Language System)


Navigation Tree