Internal Medicine

(Wang) #1

0521779407-08 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:47


Glaucoma 627

■prevalence increases 5 times in African-Americans
■nearsightedness is a risk for open angle
■farsightedness is a risk for closed angle
■main risk is high intraocular pressure (usually over 20)
■glucocorticoid use also a risk factor (usually topically or intrana-
sal)

Signs & Symptoms
■Open angle glaucoma is without symptoms
■Closed angle glaucoma preceded by periodic misty vision or rainbow
colored haloes
■Acute closed angle causes sudden, severe trigeminal pain, blurring
and often associated nausea
■intraocular pressure (I0P) is usually elevated
■optic nerve cup is expanded – loss of rim tissue
■A thin cornea (<555 microns) triples risk of glaucoma
■visual acuity is usually normal in chronic glaucomas
■secondary glaucomas may mimic primary disease, angle recession,
exfoliation, pigmentary, steroid induced

tests
■Tonometry to check IOP-tonopen or Applanation
■Visual field testing-automated
■Optic nerve visualization
■Gonioscopy to visualize open and normal angle

differential diagnosis
■Ocular hypertension
■Inaccurate pressure readings
■Physiologic cupping of the optic nerve
■Angle closure glaucoma
■Acute glaucomas mimic other causes of painful red eye: corneal
ulcers, keratitis, iritis

management
General Measures
■Obtain accurate pressure data
■Determine degree of damage by nerve appearance and field testing
■Photography of optic nerve
■Optic nerve analysis with HRT, OCT or GDX
■Baseline threshold visual field
■Determine target pressure level (depends on damaging pressure
level and presenting degree of damage)
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