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Ocular Histoplasmosis

Definition:
Ocular histoplasmosis is  an eye disease that is a leading cause of vision loss, due to the spread of spores of the fungus Histoplasma capsulatum (histo) from the lungs to the eye where they lodge in the choroid (a layer of blood vessels that provides blood and nutrients to the retina).

click to see the pictures

There the spores cause fragile, abnormal blood vessels to grow underneath the retina. These abnormal blood vessels form a lesion known as choroidal neovascularization (CNV). If left untreated, the CNV can turn into scar tissue and replace the normal retinal tissue in the macula (the central part of the retina that provides sharp central vision. If these abnormal blood vessels grow toward the center of the macula, they may affect a tiny depression called the fovea (the region of the retina with the highest concentration of special retinal nerve cells, called cones, that produce sharp, daytime vision). Damage to the fovea and the cones can severely impair, and even destroy, straight-ahead vision. Since the syndrome rarely affects side, or peripheral vision, the disease does not cause total blindness.

It’s a common problem in the USA, particularly in a region now known as the ‘Histo belt’, which includes Arkansas, Kentucky, Missouri, Tennessee and West Virginia, where as many as 90 per cent of the population have had the infection.

Symptoms:
Many patients with histo spots in their eyes have no symptoms. Others may experience the following:

*Distorted vision..
*Blind spots
*Scars in the retina, ranging in severity

Causes:
Histoplasmosis is caused by a fungus commonly found in the dust and soil of the Mississippi-Ohio River Valley region.  Approximately 62% of the adult population living in this region are carriers. It affects men and women equally.

Histoplasmosis is contracted by inhaling dust that carries the fungal spores. Its effect on the body can vary widely in severity from one person to another.  Many carriers have no symptoms at all, but those with mild exposure may experience flu-like symptoms and mild respiratory infections. Histoplasmosis is more likely to become a serious problem in people who already have a weakened immune system.

The fungus may affect the eye by causing small areas of inflammation and scarring of the retina. These are called “histo spots” and may be found in both eyes. Their affect on vision depends on the location of the scars.  Scarring in the peripheral area of the retina may have little or no impact on vision, while a central scar affecting the macula may cause a prominent blind spot.

Most people with histo spots in the retina are totally unaware of their presence unless the central vision is affected. Studies indicate that only about 5% of those with histo spots are at risk of losing vision. Scientists have been unable find a link between the patients with minor histo spots and those who develop a severe loss of their central vision.

The syndrome is thought to be linked to hypersensitivity to Histoplasma capsulatum, rather than a direct exposure of the eyes to the micro-organism, but some experts have found DNA or genetic material from the fungus in a layer of the eyeball known as the choroid, and suspect fungal spores may lodge here and cause problems.

Risk Factors:
Some people go on to develop symptoms – usually of lung disease, although the fungus may spread to other organs – known as disseminated histoplasmosis and this can be fatal.

Very rarely the organism can spread to the eye to cause acute ocular histoplasmosis, which needs urgent treatment with antifungal medicine.

Ocular histoplasmosis can cause blindness, although it mostly affects central vision and rarely involves peripheral vision so total blindness is rare. Anyone who has lived in an area where they may have been exposed to histoplasmosis and develops eye problems must be checked for the condition.The loss of vision in POHS is caused by choroidal neovascularization.

Diagnosis:
Ocular histoplasmosis is detected with a dilated examination of the retina using ophthalmoscopy. It is usually diagnosed based on its distinctive appearance and characteristics. Fluorescein angiography is required for diagnosis and follow-up of patients with POHS.

Treatment:
Treatment requires careful consideration of FA findings and few cases may respond to corticosteroids and laser photocoagulation. A vitreo-retinal specialist should be consulted for proper management of the case.

Presumed ocular histoplasmosis syndrome and age-related macular degeneration (AMD) have been successfully treated by the drug Bevacizumab (trade name Avastin, Genentech/Roche). Ophthalmologists are using Avastin “off-label” to treat AMD and similar conditions since research indicates that vascular endothelial growth factor (VEGF) is one of the causes for the growth of the abnormal vessels that cause these conditions. Some patients treated with Avastin had less fluid and more normal-appearing maculas, and their vision improved. Avastin injections into the affected eye have been used by retina specialists since early 2005. Thus there is no long term 10 to 15 year follow up data for possible late complications. Early treatment is critical to maintaining vision.

Other treatments include Ranibizumab (trade name Lucentis) which is approved by the FDA for intraocular use. Lucentis uses a smaller molecule compared to Avastin and according to GenenTech, the smaller molecule helps lower the systemic toxicity of the drug, thereby lowering the overall risks compared to Avastin. However, Lucentis costs approximately $1,600 per injection compared to less than $100 per injection for Avastin. Research has shown  that Avastin and Lucentis to be equally effective in the treatment of POHS and AMD.

To get the best effect, the whole area affected by ocular histoplasmosis has to be treated.

Once a person has ocular histoplasmosis, they have it for life.

Regular eye exams and routine use of an Amsler Grid to monitor central vision is recommended for anyone with histo spots.

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Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose

Resources:
http://en.wikipedia.org/wiki/Presumed_ocular_histoplasmosis_syndrome
http://www.medterms.com/script/main/art.asp?articlekey=24114
http://www.stlukeseye.com/Conditions/histoplasmosis.html
http://www.bbc.co.uk/health/physical_health/conditions/ocularhistoplasmosis.shtml

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New Hope for Natural Weight Loss

Researchers have discovered that mice given curcumin experience a reduction in the formation of fat tissue and the blood vessels that feed it. Curcumin is the major polyphenol in the spice turmeric..

The growth and expansion of fat tissues requires new blood vessels, a process known as angiogenesis. In fat tissue, this process is mediated by the secretion of adipokines, such as leptin, adiponectin, resistin, interleukin-6 and vascular endothelial growth factor (VEGF). The researchers first investigated the effect of curcumin in cultured human cells to which adipokines had been added to stimulate angiogenesis. They found the ability of curcumin to inhibit angiogenesis was partly due to the reduced expression of VEGF.

They then fed mice a high-fat diet supplemented with 500 milligrams curcumin per kilogram diet for 12 weeks. Weight gain was reduced in mice that received curcumin. The researchers attributed this reduction to a decrease in total body fat in the curcumin-fed animals. Mice that received curcumin also had lower liver weights, and experienced a reduction in VEGF, indicating reduced angiogenesis.

Furthermore, total cholesterol, triglycerides, and free fatty acids were lower in mice that received curcumin compared with groups of unsupplemented animals.

Resources:

Life Extension Magazine April 21, 2009
Journal of Nutrition May 2009;139(5):919-25

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Fluorescein Angiography (Test for Diabetic Retinopathy)

Alternative Names: Retinal photography; Eye angiography

Definition:
Fluorescein angiography is an eye test that uses an special dye and camera to look at blood flow in the retina and choroid……...CLICK & SEE

By looking into the back of your eye (the retina), eye doctors can see changes in the blood vessels there that show whether you are at risk for losing vision from diabetes or other causes. The earliest changes can be seen only with a special test called fluorescein angiography. For this test, a chemical that temporarily makes the blood vessels fluorescent and shows very tiny leaks in them is injected into one of your arm or hand veins while you are having your eyes examined.

This test is used to determine if there is proper circulation in the blood vessels of the retina. It can also be used to diagnose problems in the eye or to determine how well treatment is working.

Preparation  for the test:
You should arrange to have someone else drive you home from the eye doctor, because your eyes will be dilated; this can make your eyes sensitive to the sun and your vision blurry for a while.

You may be told to discontinue drugs that could affect the test. results. Tell your health care provide about any allergies, particularly reactions to iodine.

You must sign an informed consent form. You must remove contact lenses before the test.

Tell the health care provider if you may be pregnant.


How the Test Is Performed

Eye drops that make the pupil dilate will be given. You will be asked to place your chin on a chin rest, and your forehead against a support bar to keep your head still during the test.

Fluorescein angiography->…..CLICK & SEE

The health care provider will take pictures of the inside of your eye. After the first group of pictures are taken, a special dye called fluorescein is injected into your vein, usually at the bend of the elbow. A special camera takes pictures of the dye as it moves through the blood vessels in the back of the eye.

More photographs are taken up to 20 minutes after the injection.

What happens when the test is performed?
You have drops put into your eye to make the pupil dilate (open), and you have to wait for about half an hour while the drops take effect. Before giving you any other medicine, your doctor might first examine your eyes for signs of bleeding or debris outside of your retina arteries; these are signs of more advanced eye disease from diabetes. Then a nurse inserts a small needle into one of the veins in your arm or hand so that you can have a dose of medicine injected. Your doctor uses a special eye camera to take pictures of your retina. You look into one side of the camera while your doctor looks through the other side. The camera shines a dim blue light into your eye, which causes the dye flowing through the retina arteries to show up as fluorescent green. The doctor takes a collection of pictures of your eyes to review more closely later.

This color retinal photograph demonstrates nonproliferative diabetic retinopathy. The image is centered on the macula (the part of the retina responsible for central fine vision) with part of the optic nerve seen on the left of the photo (left eye). There are hemorrhages within the retinal tissue on the right side of the photograph.

How the Test Will Feel
When the needle is inserted , some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

When the dye is injected, you may have mild nausea and a warm sensation. These symptoms are usually very brief.

Normal Results:
A normal result means the vessels appear a normal size and there are no blockages or leakages.
Back to TopWhat Abnormal Results Mean
If blockage or leakage is present, the pictures will map the location for possible treatment.

An abnormal value on a fluorescein angiography may be due to:

*Blood flow (circulatory) problems
*Cancer
*Diabetic or other retinopathy
*Inflammation or edema
*Macular degeneration
*Microaneurysms — enlargement of capillaries in the retina
*Tumors
*Swelling of the optic disc

Additional conditions under which the test may be performed:

Retinal detachment
Retinal vessel occlusion
Retinitis pigmentosa

Risk Factors:
There are no special risks from this test, although your vision may be blurry for an hour or more after the test because your pupils are dilated. The dye fluorescein is excreted from your body in your urine, which might give your urine a bright or discolored appearance for a day.

There is a slight chance of infection any time the skin is broken. Rarely, a person is hypersensitive to the dye and may experience:

*Dizziness or faintness
*Dry mouth or increased salivation
*Hives
*Increased heart rate
*Metallic taste in mouth
*Nausea and vomiting
*Sneezing
*Serious allergic reactions are rare.

Your urine will be darker, and possibly orange in color, for a day or two after the test.

Must you do  after the test is over?

You will need to wear sunglasses for a few hours until your pupils are no longer dilated.

Considerations:
People with cataracts will have less accurate test results.

How long is it before the result of the test is known?
Your doctor can often discuss the results of the test with you at the end of your visit. He or she might recommend treatment (such as eye laser treatments) if your test reveals retina disease.

Click to see:->How does diabetes affect the retina?

Resources:
https://www.health.harvard.edu/diagnostic-tests/fluorescein-angiography.htm
http://health.nytimes.com/health/guides/test/fluorescein-angiography/overview.html

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Ginger Inhibits Ovarian Cancer Cell Growth

Ginger may be useful for treating and preventing ovarian cancer, according to a new study.

……………………………>....click & see

The spicy root not only has antioxidant and cancer-fighting properties, but the study also found that the ginger component gingerol exerts anti-inflammatory effects by mediating NF-KB, a protein complex that regulates your immune system’s response to infection.

In the study of cultured ovarian cancer cells, ginger inhibited growth and modulated secretion of angiogenic factors, which is a fundamental step in the transition of tumors from a dormant state to a malignant state.

The ginger also inhibited vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8), two compounds that are related to cancer growth.

Sources:
Chinese Medicine News January 2, 2008
BMC Complementary and Alternative Medicine December 20, 2007, 7:44