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New Procedure Aims To Save Vision Of Children With Eye Cancer

Article Date: 07 May 2010

An ophthalmologist at Washington University School of Medicine in St. Louis is implanting radioactive discs in the eyes of children with a rare cancer in an attempt to save their vision and their eyes. J. William Harbour, MD, is one of only a few doctors nationwide to use the approach for treating a rare, childhood eye cancer, called retinoblastoma.

The Immune System, More Than Meets The Eye?

Article Date: 06 May 2010

For some years now a small group of scientists have been pioneering a revolutionary idea that the vertebrate immune system could have a role in the regulation of iron in the body. And now, a work soon to be published in the journal Immunology, shows that human lymphocytes (white blood cells) actually produce hepcidin, the most important protein in the regulation of iron levels in the body.

How Accurate Is Retinal Scanning?

Article Date: 05 May 2010

You can't change the back of your eye so it definitely is a proof positive method of identification," said Dr. Proctor. "Use of retinal scanning as a means of identification has been around for awhile; technology has now caught up with the idea and advanced computerization including database availability can make this a reality."

Blindness And Sense Of Smell

Article Date: 04 May 2010

"There is an urban legend that blind people have better smell than the sighted. We are proving this to be false," says Maurice Ptito, a professor at the Université de Montréal School of Optometry and Beaulieu-Lefebvre's thesis director. "However, the blind do set themselves apart when it comes to cognitive efforts."

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Causes of Conjunctivitis

If your eye becomes red and irritated, let your eye doctor take a look.

Causes of Conjunctivitis

Determining that you have conjunctivitis is usually easier than determining how your conjunctiva became inflamed. However, there are a few common culprits that you should know about. Click here to learn more about conjunctivitis. If your eye becomes red and irritated, let your eye doctor take a look. The irritation could be due to something very simple and benign, but it also could be the early stages of something much more serious.

Bacterial infection

As one of the most common infections on the planet, bacterial conjunctivitis is usually self-limiting, but it can escalate to something more serious. Bacterial infection can also sometimes signify a severe underlying systemic disease.

If one were to go out and take culture swabs from the eyes of 100 random people on the street, it’s highly probable to find that all of them would have bacteria growing on their conjunctiva. Fortunately, there are built-in defense mechanisms preventing these bacteria from multiplying and causing infection. It’s when something happens to lower our defense mechanisms that these bacteria seize the opportunity to cause infection.

Conjunctivitis spreads easily and quickly. Here’s a typical sequence of events: I have conjunctivitis. I rub my eyes. I touch a doorknob or shake hands with you. You rub your eyes. You have conjunctivitis.

Viral infection

Adenovirus
Viral infection of the conjunctiva is extremely common. Of all the viruses that can cause conjunctivitis, adenovirus, the ever-present virus that lurks in our nose, throat and upper respiratory airway, is probably the most common. Adenovirus can spread like wildfire and the infection can cause significant discomfort to an individual. Unfortunately, it can also persist for weeks.

Frequent hand washing is important as adenoviruses are hearty. A virus from an infected person can survive on a counter top, refrigerator handle or door knob for several days, just waiting to be picked up by its next victim.

If there were one eye infection more deserving of the term ‘pink eye’, it would be adenoviral infection, for the inflammation in these infections causes the eyes to turn a very pink color.

Type I herpes simplex

Another, not-uncommon, cause of viral conjunctivitis is the herpes virus. Type I herpes simplex, better known as “above-the-waist” herpes, has at one time or another infected over 90% of the population. This form of herpes, which is not the sexually-transmitted form of the disease, initially manifests as a flu-like illness in childhood. The problem is, in most people, the virus remains in the body, existing in a dormant state in the nervous system. Periodically, usually during times of stress, the virus becomes activated and causes infection, usually in the form of cold sores of the lip, skin rashes, or eye infections.

Currently, there are no medications to treat adenoviral infection, but if it is caught early, its discomfort can be minimized. There are several medications to combat (not cure) herpes eye infections. However, the virus continues to run its course in some individuals, being a major cause of severe corneal scarring that could require transplantation.

Most viral conjunctivitis, although usually benign and self-limiting, tends to follow a longer course than acute bacterial conjunctivitis, lasting for approximately 2-4 weeks.

What’s the best way to get a viral infection?

Don’t wash your hands.
Another way that viral particles are passed from person to person is through respiratory droplets. When an infected person sneezes, zillions of contaminated droplets enter the immediate airspace. These particles are picked up by air currents and can easily drift into another person’s airspace and then inhaled. If some of these freely floating droplets happen to land on your conjunctiva, there could be trouble ahead, in the form of full blown conjunctivitis, or worse yet, a cold or the flu. Viruses can also be passed on through contaminated swimming pools and spas.

Allergic conjunctivitis

Since the conjunctiva is a mucosal surface similar to the nasal mucosa, the same particles that trigger hay fever or allergic rhinitis may also trigger an allergic conjunctivitis.

Common pollen and airborne particles from grasses and weeds can trigger an allergic reaction. These particles can provoke the symptoms of acute allergic conjunctivitis which include: itching, redness, burning, and tearing. Allergic conjunctivitis can be a seasonal disorder, or it can plague certain individuals throughout the course of the year.

What does conjunctivitis look like?

All too often, medical textbooks make it sound as if the differentiation of viral and bacterial conjunctivitis couldn’t be more obvious. This is not always the case, as these two infections often have very similar clinical manifestations. In both cases the eyes are red, though viral infections tend to be more brilliantly red. Another point of differentiation is the type of discharge. Usually, viral infections trigger a characteristic watery discharge, whereas the discharge in a bacterial infection is typically thick and mucous-like with a yellow-green color. Both infections can show signs of irritation, swelling and pain.

Allergic conjunctivitis, too, presents as a red, swollen, irritated eye. But what gives allergy away is the characteristic itching. To eye doctors, itching means allergy until proven otherwise. Allergic conjunctivitis sufferers usually have a lot of mucous strands in their eyes.

Treatment of conjunctivitis

To combat conjunctivitis that is due to a bacterial infection, there are some very potent antibiotics that can be of help. However, there are no anti-virals at this time that eradicate the herpes virus from the body. There are medications that will stop the infection in its tracks, but the virus will continue to live in the nervous system. No cure or method to kill adenovirus yet exists. When patients are infected with adenovirus, therapy is directed towards minimizing symptoms and tissue damage.

Treatments for allergic conjunctivitis consist of a host of relatively new medications designed to suppress the allergic response and minimize the patient’s symptoms.

See your eye doctor

If your eye is red, swollen, or painful, it’s important that you see your eye doctor right away. Don’t assume that your eyes are red because you didn’t get enough sleep or because you had too much to drink. If you do have an infection, it’s important that the fire is put out immediately before any tissue damage takes place.

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