Archive for December, 2009
Myopia, (nearsightedness) is becoming shockingly more common
12.16.2009Myopia, also known as nearsightedness, is becoming increasingly common. A study published in this week’s Archives of Ophthalmology shows an alarming rise in the rates of myopia among Americans. Americans aren’t the only ones experiencing this decline in their vision. All across the globe there is an increase in cases of myopia.
Myopia is a common type of refractive error which causes distant objects to appear blurry when not wearing eyeglasses or contact lenses. Close objects, however, are often clear. Nearsightedness is caused when the eyeball is too long, which causes light to focus in front of the retina. An abnormal shape of the lens or the cornea can cause myopia as well.
While nearsightedness can affect both children and adults, it is most frequently diagnosed in children between the ages of 8 and 12 and can progressively get worse during the teen years. No changes may occur between the ages of 20 and 40 but the condition can worsen with age. Children from nearsighted parents are more likely to develop the condition.
Researchers at the National Eye Institute reported that rates of myopia in people age 12 to 54 increased from 25% in 1971-972 to 41.6% in 1999-2004. People with mild to severe forms of myopia were included in this survey. The dramatic increase in myopia cases points to the need for further research as to what causes the condition and what steps, if any, could be taken to prevent the condition.
The results were based on data gathered from 4,436 black or white Americans from 1971 to 1972 and from 8,339 black or white Americans from 1999 through 2004. The most dramatic rate increase in myopia was noted among black Americans where an increase from 13% in the first survey period to an alarming 35% in the second survey period was noted.
An explanation for some of the increase in cases of myopia could be the improved access to eye screenings and earlier diagnosis of the condition. Better eye care, however, does not explain all of it. Some fault may lie with the fact that children are spending more time in front of computers and video games and less time outdoors. Such activities could cause the eyes to become geared toward these “near-vision” tasks.
Andrea Schumann
Staff Writer
Discovery of New Inherited Eye Disease
12.14.2009The discovery of a new inherited eye disease will hopefully provide a deeper understanding of other common retinal diseases. The new eye disease which affects the macula was discovered by scientists at the University of Iowa.
Bleeding in macular portion of retina
Such a discovery is rare. Dr. Vinit Mahajan, the lead author reports that finding a new inherited eye disease affecting the macula is extremely uncommon.
The article detailing the findings is in the November 9 issue of Archives of Ophthalmology. The newly discovered retinal eye disease causes abnormal blood vessels to form in the macula. These malformed blood vessels are inclined to bleed and this leads to both swelling and scars that affect vision. These symptoms are generally connected with another condition known as wet macular degeneration.
Researchers made this discovery when one person in a family came in for care for eye problems. If the doctors had just examined the one patient, macular degeneration would have most likely been the diagnosis. They suspected something was else was going on and they examined 20 extended family members with varying visual problems. The result was the discovery of the new eye disease.
Researchers are hopeful that the discovery of this new macular eye disease will bring about a greater understanding of other eye diseases.
Andrea Schumann
Staff Writer
Taking Aspirin Does Not Decrease Risk of Vision Loss in Elderly
12.09.2009Aspirin is a cheap over-the-counter-medication that is often hailed for its benefits in reducing the risk of heart attack in patients. However, aspirin does not decrease the risk of vision loss in elderly patients.
A study published in the December 2009 issue of Ophthalmology concluded that aspirin had no notable effect on the risk of developing age-related macular degeneration (AMD).
This study took place over several years and was designed to examine whether taking low-dose aspirin on alternate days affects the development of AMD. The study did utilize data from a larger study on aspirin. The study involved 39,876 healthy, female health professionals aged 45 years or older and followed them for an average of 10 years.
While the study findings are only applicable to women, it is noted that AMD is more common in women than in men. Also, there are risks associated with taking daily or alternate-day aspirin and those risks should be weighed against the benefits.
Andrea Schumann
Staff Writer
Patient’s Own Stem Cells May Provide Treatment for AMD
12.07.2009Stem cells that can be derived from patients may provide a possible treatment for age-related macular degeneration (AMD). Unlike embryonic stem cells which can cause an immune rejection in the patient, induced stem cells are taken from the patient directly.
The cells in question are known as retinal pigmented epithelial (RPE) cells and they are vital for visual function. Researchers hope that transplanting fresh RPE cells from the patient into the patient’s retina will allow the photoreceptors (rods and cones) in the patient’s eye to stay healthy, which will in turn prevent vision loss.
In a paper published in last week’s PloS One, researchers worked with rats that have a mutation which causes a defect in RPE cells which ultimately leads to vision loss. The researchers discovered that by surgically inserting the stem cell-derived RPE into the rats’ retinas before photoreceptor degeneration, they were able to retain the vision of the rats.
While the scientists note that much more research needs to be done, they are encouraged by the findings of this study and hope that this type of stem-cell based therapy will prove to be an effective treatment for AMD.
Andrea Schumann
Staff Writer
