Q: Please tell me where a Doppler test is preformed and how much it would cost. My husband has been told he needs this test due to severe problems with leg veins and a testicle.
A: In deciding to have any medical test, I recommend that you understand several important matters: (1) How does the test work? (2) How will the test help you make additional medical decisions? (3) What are the risks? (4) What are the costs?
Doppler testing is a type of sonography, also called ultrasonography. It's similar to the way submarines and bats are able to locate objects using sound. For that reason it may also be called echography, such as in echocardiology.
Sound waves are sent out into the water, air or the human body. The sound is reflected off of an object and measured when it returns. The way the sound is reflected gives a lot of information about the object's distance and size.
A big advantage of sonography is that, as with X-rays, probing the body can be done without entering it. And, unlike with X-rays, the sound doesn't harm the body.
The procedure is also quite simple. The person needs to sit or lie as still as possible. A gel is applied to the skin and a hand-held, metal object is used to make the sound and record its return.
When ultrasound technology was first introduced, it only worked well on parts of the body that weren't moving. But today it can be very effective for "looking" at moving parts such as the heart and blood in the arteries.
In fact, Doppler ultrasound depends on movement. The change in pitch you hear when a car or train passes also occurs as a moving substance, such as your blood, passes through the ultrasound. This effect is called the Doppler effect.
Doppler tests of the arteries not only "look" but also listen to them. Blood that passes through a constricted artery, as with atherosclerosis, makes more sound than blood flowing through a smooth artery.
This technology has come a long way over the years and can provide very important information. But it's also important to determine what the test is looking for ahead of time. And it's equally important to assess how this information will affect further treatment decisions.
For example, if the Doppler test finds constriction in the arteries of the legs or testicles, would you then want to have surgery?
As with all medical procedures, the more skillful the tester the better the results. Ultrasound testing and interpretation requires well-trained people. I presume that whoever is recommending that your husband get a Doppler test knows where it can be done or does it himself. You may want to get a referral to more than one person so you can make cost comparisons.
Update on allergies: Two recent studies may be turning the world of allergy upside down.
One study recently reported that having two or more pets in the home dramatically cut the chances of a child's developing allergies. And another study reported that children who grew up with cats had only about half as much wheezing as those growing up without cats.
But the second study also found that if a child's mother had asthma, the child was three times as likely to develop wheezing if he or she grew up with cats.
The long-held view that having pets increases allergic response may only hold true if one or more parents have asthma.
Write to Dr. Allen Douma in care of Tribune Media Services, 435 N. Michigan Ave., Suite 1500, Chicago, Ill., 60611; or contact him at DRFamily@aol.com. This column is not intended to take the place of consultation with a health-care provider.