September 2008 Mayo Clinic Health Letter Highlights Cataract Removal, Severe Headache And Dual Energy X-Ray Imaging

Main Category: Eye Health / Blindness
Article Date: 04 Sep 2008 - 0:00 PDT

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One aspect of aging that's usually fixable is cloudy vision due to cataracts.

In an otherwise healthy eye, cataract removal results in improved vision 95 percent of the time, according to the September issue of Mayo Clinic Health Letter.

Cataracts are common. By age 65, about half of all Americans have developed some degree of lens clouding due to cataracts. Diagnosed during an eye exam, cataracts develop slowly and may not hamper vision much at first. But when cataracts affect the quality of life -- interfering with driving or reading -- it's time to consider surgery, the only treatment.

The most common surgical approach is called phacoemulsification. An ultrasound probe is used to soften and break up the clouded lens, which is suctioned out. Then, the surgeon inserts an artificial flexible lens. The outpatient procedure involves minimal anesthesia and tiny incisions.

The standard lens implant has a single focus point (monofocal), meaning the implanted lens can't adjust for both distant and close-up vision as can a natural lens. When a lens is implanted for distance vision, reading glasses will be needed, and vice versa.

The Food and Drug Administration recently approved a multifocal lens implant that can provide good vision for near and distance vision. However, studies have shown the versatility comes with some tradeoffs in quality of vision. For example, distance vision with a multifocal lens may not be as good as distance vision with a monofocal lens.

Whatever lens is selected, recovery time is generally quick. Mild pain and discomfort diminishes and disappears and vision steadily improves within the first few days. After several weeks of healing, patients can select glasses or contact lenses to fine-tune their vision.

Severe Headache Could Signal Blood Vessel Inflammation

ROCHESTER, Minn. -- Severe and frequent headaches, especially in people who don't typically have headaches, warrant a visit to the doctor.

The headaches could be a symptom of vasculitis -- blood vessel inflammation. Vasculitis is an autoimmune disease, where the body's immune system mistakenly attacks healthy tissue. Depending on the type of vasculitis -- there are more than a dozen -- the disease can disrupt blood circulation and, in some cases, cause death, according to the September issue of Mayo Clinic Health Letter.

In addition to headache, symptoms might include fever, fatigue, weight loss, muscle and joint pain, appetite loss, and numbness or weakness. Often, the exact cause of vasculitis isn't known, although some forms can be linked to infections such as hepatitis B and C, as well as certain medications.

Diagnosis usually involves blood tests and imaging studies of the blood vessels. It also may include a biopsy of an affected blood vessel or tissue.

Treatment depends on the type of vasculitis, its severity and the patient's overall health. The anti-inflammatory properties of corticosteroid medications such as prednisone and methylprednisolone often improve symptoms within days. Immune-suppressing and cytotoxic drugs are used when vasculitis is severe and does not respond to corticosteroids.

Thanks to drug treatments, some types of vasculitis that were once considered fatal can be managed or even go into remission. However, side effects with the medications are a concern. Some medications can increase the risk of serious infections and some cancers. A doctor who has training in this area, often a rheumatologist, can carefully monitor the prescribed medications, their benefits and side effects to best manage the illness.

Dual Energy X-Ray Imaging -- A Better View

ROCHESTER, Minn. -- An emerging imaging technology shows that using two different levels of X-ray energy is better than one, according to the September issue of Mayo Clinic Health Letter.

The new technology, called dual energy X-ray imaging, goes beyond the single perspective image of an X-ray exam or the multiple perspectives of a computerized tomography (CT) scan. Dual energy X-ray imaging can identify the compositions of substances and tissues in the body. Images can be differentiated that would be difficult or impossible to discern in an X-ray or CT scan.

The enhanced image is created using two levels of X-ray energy. After the high-energy reading is cross-referenced with the low-energy reading, an image emerges that is much more precise than standard imaging, which uses a single level of energy.

A handful of medical centers are developing ways to use this technology. For example:

-- Identifying kidney stone compositions -- Unlike a standard CT scan, a dual energy X-ray image can determine if a kidney stone is made of uric acid or if it contains calcium. Uric acid stones can be treated with medication, avoiding surgery.

-- Detecting gout -- A dual energy X-ray image shows the presence and location of gout. Standard X-rays, even combined with a needle biopsy, don't always provide the evidence needed for a clear diagnosis.

Other applications under development are mapping blood vessel flow within organs and visualizing clogged arteries. Although current applications are limited, researchers will likely find more ways to apply dual energy X-ray imaging.

Mayo Clinic Health Letter is an eight-page monthly newsletter of reliable, accurate and practical information on today's health and medical news.

Mayo Clinic
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