Facts on File Encyclopedia of Health and Medicine

pattern of progression begins with loss of periph-
eral (outside) vision. Over time the field of vision
becomes increasingly narrow, which people often
describe as “tunnel vision.” Other symptoms
include excessive tearing (especially with close
focus tasks such as reading), halos around lights at
night, aching eyes, and headaches. Sudden throb-
bing PAIN in the eye, loss of vision, severe
HEADACHE, halos around lights, and a dilated pupil
in the affected eye are symptoms of acute closed-
angle glaucoma.

GLAUCOMA SYMPTOMS

Chronic (Open-Angle or
Closed-Angle) Acute Closed-Angle
slow loss of peripheral vision sudden, throbbing PAINin
“blind spots” in the field of the EYE
vision sudden, severe HEADACHE
halos around lights at night sudden restriction or loss
teary eyes with close focus of vision
tasks dilated pupil in affected
achiness in the affected eye eye
NAUSEAand vomiting

Though eye care practitioners routinely use
TONOMETRYto screen for increased intraocular pres-
sure, this test alone is not sufficient to detect glau-
coma. Detecting glaucoma requires a full

OPHTHALMIC EXAMINATIONincluding fundus exami-

nation to assess the condition of the optic disk.

The ophthalmologist will also conduct a visual

acuity test and a peripheral vision test. Other pro-

cedures that can help diagnose glaucoma in its

early stages or quantify the extent of damage in

moderate to advanced glaucoma are ULTRASOUNDof

the eye and OPTICAL COHERENCE TOMOGRAPHY(OCT).

Treatment Options and Outlook

Acute closed-angle requires emergency measures

to relieve intraocular fluid and the accumulation

of aqueous humor. Such measures typically

include a combination of procedures to open the

drainage angle, ophthalmic medications to lower

intraocular pressure, and systemic medications to

draw fluid from cells (osmotics). The ophthalmol-

ogist is also likely to administer medications for

pain and to minimize NAUSEAand vomiting. Ongo-

ing treatment with glaucoma medications or glau-

coma surgery is then necessary. Ophthalmic

medications (drops, inserts, and ointments) to

open the drainage angle and lower intraocular

pressure are the standards of treatment for chronic

glaucoma of either form, and typically can control

glaucoma for many years.

Surgery becomes an option to treat glaucoma

that becomes advanced or does not respond to

glaucoma 93

COMMON GLAUCOMA MEDICATIONS

Type of Drug Actions
alpha-blockers (apraclonidine, brimonidine)—topical reduce aqueous humor production by slowing function of
ophthalmic preparations ciliary processes; increase drainage of aqueous humor

beta-blockers (betaxolol, carteolol, levobunolol, reduce aqueous humor production by slowing function of the
metipranolol, timolol)—topical ophthalmic preparations; ciliary processes
oral products sometimes used

carbonic anhydrase inhibitors (brinzolamide, reduce aqueous humor production by blocking the action of the
dorzolamide)—topical ophthalmic preparations enzyme necessary for its production, carbonic anhydrase

miotics (pilocarpine, carbachol)—topical ophthalmic increase drainage of aqueous humor
preparations

prostaglandin analogs (latanoprost, travoprost, bimatoprost, increase drainage of aqueous humor via secondary routes
unoprostone)—topical ophthalmic preparations