New Perspectives in Glaucoma, Cataract, and Antioxidants
Kimberly K. Reed, O.D., FAAO
I.
Introductory Remarks
a. Glaucoma is multifactorial
b. Discrepancies
i. Why do racial differences exist?
ii. Why do some patients progress with treatment,
and some patients don’t progress even without
treatment?
iii. If IOP is the only mechanism, “how low can you
go?”
II.
Definitions
a. Complementary Medicine: Used together with
conventional medicine
b. Alternative Medicine: Used in place of conventional
medicine
III.
Currently accepted theories of the pathogenesis of
glaucoma
a. Increased IOP
i. Most research historically in this area
ii. Pharmaceutical therapy focused in this area
iii. Is high IOP the cause, or the result?
b. Oxidative damage
i. Free radicals: Review
1. Reactive Oxygen Species (ROS)
a. Generated from utilization of oxygen in
normal processes
b. Formed in higher-than-usual numbers in
several circumstance
2. Current understanding of oxidative damage
in glaucoma
a. Ganglion cell mitochondria appear to
be most affected by ROS damage
ii. Parallels in other disease
1. AMD
2. Vascular disease
3. Neurological disease
4. “Aging” skin and joints
c. Vascular dysregulation
i. Review of vascular supply to the optic nerve
ii. Repeated vascular nonperfusion is proposed
mechanism
1. fluctuations in systemic blood pressure
2. several mechanisms downstream of mild
nonperfusion events
a. oxidative stress
b. others
3. glaucoma patients vs non-glaucoma patients
characteristics
4. Timing factors: overnight vs daytime
5. Age factors: elderly vs young
IV.
Proposed Complementary and alternative therapies
a. Antioxidants
i. mechanism of action
ii. examples
1. red wine
2. green tea
3. dark chocolate
4. coenzyme Q10
5. turmeric
6. ginkgo biloba
b. Salt (sodium chloride)
i. Increases systemic blood pressure
ii. Contraindicated in vascular disease or pre-existing
HTN
c. Omega-3 fatty acids
i. Promote overall vascular health
ii. Usually associated with mild reduction in systemic
BP
1. despite this, benefits seen in many studies
with glaucoma
2. probably due to overall stabilization rather
than reduction of BP
d. Magnesium
i. May enhance vascular regulation
e. Melatonin
i. Improves regulation of seasonal and circadian
rhythms
ii. Involved in dynamics of aqueous humor
iii. Reduction in IOP shown in several animal studies
iv. Also is an antioxidant, giving secondary potential
mechanism
v. Systemic effects largely unknown
f. Acupuncture
i. Lowers IOP in several animal studies
ii. Small human study had mild IOP lowering result
iii. No large-scale studies currently support
g. Sleeping position
i. IOP usually increases when supine
1. may be more pronounced in glaucomatous
eyes
ii. Moderate IOP reduction overnight achieved with
slight head elevation (two or three pillows)
h. THC
i. Active ingredient in marijuana
ii. Well-known, reliable, and impressive IOP-lowering
effects
iii. CNS effects make widespread use impractical
iv. Legislation issues
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