Glaucoma

[liveonearth]

GLAUCOMA
--second leading cause of blindness in the world: COMMON
--fluid pressure inside eye damages optic nerve
--fluid is called aqueous humor, it's the gel that fills everybody's eyeballs
--aqueous humor is constantly produced, drained, recycled, NORMALLY
--when drainage system fails-->glaucoma

--mb ASx in early stages
--approx 1/2 4 million + Americans with glaucoma do not know they have it

CHRONIC, OPEN ANGLE GLAUCOMA
--called “silent thief of sight” because it's usually gradual
--by he time you have vision loss, the damage mb permanent
--may occur when eye pressure is normal (uncommon), dt? atherosclerosis/other circ problem
--most common type: open-angle (chronic) glaucoma
--Sx: blurry peripheral vision first-->tunnel vision-->blindness
--eye is NOT red

ACUTE, CLOSED-ANGLE GLAUCOMA
--10% of cases, sudden increase in pressure
--Sx: severe pain, halos around lights, red eye, nasea
--Sx: sudden blurring of vison or blindness
--usu presents with peri-orbital pain and visual deficits
--pain is boring in nature and asociated with an IPSILATERAL HEADACHE
--in large % of pts, extraocular symptoms and systemic manifestations are chief complaint
--PE: reveals ability to detect hand movmeents but not ID digits on distance or near charts
--here's acute in a pet:

--may be precipitated by drugs (sympathomimetics, anticholinergics, antidepressants), dim light, rapid correction of hyperglycemia
--DDX: conjunictivitis, acute iritis
--Tx: refer immediately to optometrist, eyesight may be lost permanently within 24 ours

RISK FACTORS
--being African American (6-8x more common than in whites)
--also Mexicans, Asians, Japanese have higher risk
--age: over 60, but can occur in younger folks!
--diabetes
--high blood pressure
--heart disease
--hypothyroidism
--family hx
--eye injuries: retinal detachment, tumors, inflam, surgery
--near sightedness
--prolonged use of corticosteroids esp eye drops
--smoking is more of a risk factor for macular degeneration

DIAGNOSIS
--"air puff" test = tonometry, test each 3-5 years or with fam hx annually

--10-21mm Hg = normal, 25-50 = high
--eye pressure has normal variations of 3-4 mm Gh or more
--one borderline Normal test does not rule out glaucoma
--need to test corneal thickness too, new test: pachmyetry


--thin cornea-->easy to dent with puff-->missed diagnoses
--thick cornea-->hard to dent with puff-->incorrect diagnosis
--cupping may be visible on opthalmoscopic exam



TREATMENTS
--conventional: drugs, surgery-->increased cataract risk, both, eye drops with SE's incl blurred vision, resp probs, forgetfulness, lowered HR, burning/stinging
--if pressure is 18-20 mm Hg, Dr Thom recommends 1 drop/day
--two most important preventative measures (per Mercola) are: lower your insulin levels and exercise regularly
--also helpful: take an animal-based omega-3 supplement, this also helps prevent macular degeneration
--get lots of lutein from green, leafy veggies
--get lots of zeaxanthin from raw egg yolks (destroyed by cooking)
--these two nutrients are fat soluble so eat some fat with the meal (yes even with the greens)
--avoid trans fats
--eat dark-colored berries in moderation: blueberry, bilberry, cranberry-->strengthen capillaries

SOURCES:

6 Sure-Fire Tips to Prevent Glaucoma Naturally
by Dr. Mercola
http://articles.mercola.com/sites/articles/archive/2009/03/31/Six-Natural-Strategies-to-Stop-Glaucoma-from-Robbing-You-Blind.aspx

also: Dr Thom's eye notes, CPD fall 2008