DEAR DR. DONOHUE: I have read articles you have written on urine incontinence but haven’t seen anything on bowel incontinence. I am a 48-year-old woman and have had several episodes of loss of control. What can I do about it? It seems to hit about half an hour after having a salad at a restaurant. This is quite embarrassing. – Anon.

ANSWER: Millions suffer from loss of bowel control, and many suffer in silence, too embarrassed to mention it to their doctors. That’s a shame, for there is hope to regain control.

Your situation appears to be intermittent and due to loose stool after eating salads. Avoiding salads is, of course, one answer. For others with loose-stool incontinence, control can often be achieved by slowing the transit of undigested food through the intestine. That allows more water to be absorbed from it and produces more solid stool that the anal sphincter – the muscle that holds the rectum closed – can retain. People with this problem should not drink fluids with their meals. They should avoid tea, coffee, chocolate and other caffeine-containing foods and drinks.

For others, bowel incontinence comes about from a loss of tone of the muscles of the pelvic floor. Kegel exercises – the same ones used for urinary incontinence – can improve bowel control. While urinating, deliberately stop the flow. That is the muscle contraction needed to strengthen pelvic muscles. Such contractions should be done many times during the day.

There are people whose problem lies with the anal sphincter itself. It might have faulty nerve connections, or, in women, it might have been injured while giving birth. Surgical corrections for this problem exist, including an artificial sphincter and the transplantation of muscle to fashion a new sphincter.

Proctologists and gastroenterologists are the doctors who are experts in dealing with this condition.

DEAR DR. DONOHUE: What can you tell me about Baker’s cyst? I have it, and my left knee is killing me. – E.B.

ANSWER: You’re familiar with housemaid’s knee, right? It’s a soft swelling on the front of the knee. It’s a fluid-filled bursa. Bursas are lubricated disks located between tendons and bones that lessen friction as tendons glide over the bone.

A Baker’s cyst is a behind-the-knee version of housemaid’s knee. There’s a bursa there. It connects with the knee joint, and often fluid fills that bursa because of trouble in the knee joint – arthritis or damaged cartilage.

The fluid often goes away with rest and anti-inflammatory drugs like ibuprofen. If it doesn’t, a doctor can drain it and inject cortisone to prevent it from coming back. Rarely is surgery needed.

A thorough examination is an essential part of Baker’s cyst treatment.

DEAR DR. DONOHUE: Please inform me how an MRI works and if there are any side effects from it. – D.R.

ANSWER: Magnetic resonance imaging – MRI – is a technique of obtaining exceptionally clear pictures of internal body organs and structures without having to use any radiation. Powerful magnets generate waves that can delineate internal anatomy with astounding sharpness.

It has become a commonplace test. More than 10 million MRI procedures are done every year in the United States.

People with implanted metallic devices like pacemakers cannot have an MRI. The magnetic field can cause them to malfunction.

No special preparations are needed for most MRI tests. The patient lies on his or her back in a tunnel-like structure for approximately 30 minutes while the pictures are taken. Some people are claustrophobic and find the confinement most unpleasant. Those people can be mildly sedated. In some facilities, MRI machines are more open and don’t create such a problem. The machines are noisy, however. Be prepared for that.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.