Glaucoma is a slowly progressing deterioration of the optic nerve, associated with elevated intraocular pressure (IOP) and associated compromise to visual acuity. There are four types of glaucoma. Chronic open-angle glaucoma (COAG), the most common type, accounts for 90% of the cases in the United States. Juvenile open-angle glaucoma is essentially the same disease but occurs in patients under 40 years of age and is largely genetic in origin. Acute angle-closure glaucoma (AACG) is less common but presents a medical emergency. Congenital glaucoma is a rare form of open-angle glaucoma, affecting children from birth to age 3. COAG affects about 4% of the population over 40 years of age and is the leading cause of blindness for African-Americans. If diagnosed early and treated appropriately, less than 10% of glaucoma patients will proceed to blindness.

Elevated IOP causes optic nerve cupping and damage. Etiology may be related to age, head trauma, or other diseases, but is not entirely understood.

• Increased age
• Family history
• African-American descent
• Eyes with shallow anterior chambers—risk for angle-closure glaucoma
• Diabetes
• Myopia
• Drugs: antihistamines, antihypertensives, corticosteroids
• Food sensitivities
• Stress
• Sedentary lifestyle
• Hypothyroidism

COAG:

• Typically asymptomatic until well advanced, with loss of visual acuity
• Loss of peripheral vision
• Elevated IOP
• Cupping of optic nerve

AACG:

• Dramatically elevated IOP
• Eye appears red
• Pain
• Edema
• Cloudy cornea
• Blurred vision
• Colored halos around lights
• Nausea, vomiting
• Headache

Congenital glaucoma:

• Corneal edema confirmed by corneal haziness
• Corneal diameter > 12 mm
• Visual impairment
• Light sensitivity
• Corneal tearing

• Anterior uveitis
• Cerebral or ocular malignancy

Diagnosis includes measuring the optic disk and IOP as well as testing the visual field. A disk ratio of 0.7 or greater requires diagnostic screening. Serial examinations revealing a steady increase in optic cup size are diagnostic of glaucoma. Patients with elevated IOP may not have glaucoma, and, conversely, a surprising number of patients with glaucoma have normal pressure. Therefore, IOP tests only help to confirm diagnosis. Benefits outweigh risks for full dilation to evaluate presence of a fundus lesion.

• Elevated IOP—increased vascular resistance and decreased vascular perfusion cause optic nerve damage
• Nerve fiber and supporting tissue destruction cause shrinkage or notching of the rim and enlargement of the cup of the optic disk
• Arcuate scotomas—area of lost or depressed vision
• Aqueous humor reabsoption is impaired by a block in the trabecular meshwork with COAG; iris obstructs the trabecular meshwork with closed-angle glaucoma

• Opthalmoscopy—measures cup-to-disc ratio
• Photographic or scanning laser images—reveals optic nerve damage
• Gonioscopy—reveals narrowed chamber angle, distinguishing closed- from open-angle glaucoma; uses a specially mirrored contact lens with high magnification

• Perimetry—measures loss of peripheral vision
• Schiøtz, applanation, or Goldmann's applanation tonometer—measures IOP

Although glaucoma is not curable, visual loss can be minimized with early detection and IOP control. IOP needs to be reduced by 25% to 30% of pretreatment levels, generally about 15 to 17 mm Hg. Medications are usually begun in the affected eye, and the non-affected eye is treated prophylactically at a later point. Often a combination of medications is used until the IOP is lowered. Adjustments are made as side effects develop. Laser surgery is about as effective as drug treatment.

COAG:

• Prostaglandin agonist—new class of drugs to lower IOP (e.g., latanoprost 0.005% qhs); more effective than beta-blockers with fewer side effects; side effects include thicker, darker lashes and hazel eyes becoming more brown
• Topical beta-blockers—reduces IOP approximately 25% (e.g., timolol 0.5%/day); systemic side effects from drops—bradycardia, hypotension, bronchospasm, impotence, depression
• Topical pilocarpine—contracts ciliary body, opening the trabecula to increase aqueous outflow, thus reducing IOP; side effects—miotic pupil with vision dimming, myopia, conjunctival hyperemia, retinal detachment, diaphoresis, diarrhea, leukocytosis
• Topical adrenergic agonists—helps lower IOP by increasing endogenous cholinergic effects; ocular side effects similar to pilocarpine, plus cataracts
• Topical and oral anhydrase inhibitors—reduce aqueous production (e.g., topical dorzolamide); side effects: topical—metallic taste; oral—malaise, gastrointestinal upset, renal stones

AACG:

• Attempt to induce miosis with topical beta-blockers, topical or oral acetazolamide, or topical pilocarpine
• Intravenous mannitol used to promptly lower IOP; 1 to 2g/kg body weight
• Solution of isosorbide 45% used to promptly lower IOP; 1 to 2g/kg body weight

Laser:

• Argon laser trabeculoplasty—opens aqueous outflow by burning the surface of the trabecular meshwork in the anterior chamber angle
• Argon laser peripheral iridoplasty—performed prophylactically or emergently for angle-closure to break an attack; pulls iris out from the trabecular meshwork
• Yttrium aluminum garnet (YAG) laser—for acute angle-closure glaucoma to relieve pupillary block by making a hole in the pupillary iris; also done prophylactically

Trabeculectomy—surgically constructed filter controls release of aqueous outflow; about 80% effective, 5% to 10% risk of reoperation or diminished vision

Nutrients and herbs strengthen the vasculature of the eye and provide antioxidant protection. Homeopathy may be effective for acute pain relief. Regular aerobic exercise may help treat the condition as well.

• Exposure to allergens may produce altered vascular permeability and increase IOP. All known food allergens should be eliminated. Reduce foods that may dramatically alter blood glucose, such as sugars, fruits, and refined foods.
• Include foods rich in bioflavonoids and carotenes, such as dark berries, dark leafy greens, and yellow and orange vegetables.
• Vitamin C (500 to 1,000 mg tid) may help reduce IOP.
• Vitamin E (400 to 800 IU/day) and vitamin A (10,000 IU/day) or beta carotene (25,000 IU/day) for antioxidant protection.
• Thiamine (10mg/day) is often deficient in glaucoma.
• Coenzyme Q10 (100 mg once or twice daily) is a powerful antioxidant and may help minimize cardiovascular side effects of beta-adrenergic blocking agents.
• Ocular tissue is rich in trace minerals, and supplementation with zinc (30 mg/day) and selenium (200 mcg/day) should be considered.
• Omega-3 fatty acids (300 to 500 mg daily)
• Melatonin (2 to 5 mg before bed)

Herbs may be used as dried extracts (pills, capsules, or tablets), teas, or tinctures (alcohol extraction, unless otherwise noted). Dose is 1 heaping tsp. herb/cup water steeped for 10 minutes (roots need 20 minutes).

• Bioflavonoids have collagen-stabilizing effects and may reduce IOP.
• Bilberry (Vaccinium myrtillus) 100 to 200 mg bid
• Rutin 20 mg tid, especially with associated allergies
• Hawthorn berries (Crataegus monogyna) 200 mg bid, especially with concurrent hypertension
• Ginkgo (Ginkgo biloba) 120 mg bid, especially with compromised circulation
• Combine equal parts of ginkgo, hawthorn, bilberry, and elderberry (Sambucus nigra) in a tea (three cups/day) or tincture (60 drops bid) to strengthen vascular tissues and improve circulation.

The following eye drops are toxic in large doses and should be used only under a health care provider's supervision. Adverse reactions are diarrhea, nausea, salivation, perspiration, and vomiting. Drops should be diluted in an eyecup filled with distilled water. Both herbs reduce IOP.

• Calabar bean (Physostigma venenosum) one to two drops tid
• Jaborandi (Pilocarpus microphyllus) two to five drops tid

An experienced homeopath would consider the individual's constitution. Some of the most common acute remedies are listed below. Acute dose three to five pellets of 12X to 30C every one to four hours until symptoms resolve.

• Phosphorus for glaucoma, especially with vertigo
• Physostigma for glaucoma, especially with muscle spasms and neurological problems
• Spigelia for glaucoma, especially left-sided with sharp pains

• Use gonioscope to insure that drainage angle of the eye is visibly open after angle-closure treatment or laser surgery
• Careful follow-up reduces complications

Glaucoma is not preventable, but early detection and IOP control reduces visual loss. Drugs that increase IOP should be avoided in patients at risk for glaucoma. May consider prophylactic laser treatment of eye not yet affected.

• Acute angle-closure glaucoma—may result in permanent vision loss or blindness
• Damaged optic nerve—increasingly more vulnerable to elevated IOP
• Falls—occur significantly more in elderly patients with visual impairment

Because central field vision is spared until end-stage disease with COAG, serious damage may occur before it is diagnosed.

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