FROM POLIO PREVENTION TO 'THE PILL': THE CENTURY'S TOP 10 ADVANCES

It wasn't that long ago that children were forbidden to swim in the water for fear of catching polio.

And being born a couple of months premature almost always meant a death sentence.

These were the days when cataract patients could look forward to recovering from their surgery by spending two weeks in bed with their eyes patched and their heads surrounded by sandbags.

To say we've come a long way in the world of medicine is an understatement of mammoth proportions.

Nowadays, vaccinations have rendered some of the most dreaded diseases fodder for the history books.

Some surgeries don't even require an incision anymore.

And computer imaging can tell a doctor more about a patient than an exploratory operation.

It seems like every week, a new drug pops up on pharmacy shelves, some cutting-edge medical treatment gets approved, and researchers make another discovery that helps better our collective understanding of the human body.

These are the tiny steps that make up a marathon of medical advances over the 20th century.

Some of these steps have taken us further than others. They are the discoveries and innovations that helped get us where we are today.

Just what are the top medical advances in the last 100 years?

We've asked leading medical experts in 10 disciplines to answer that question, and here's what they had to say.

The heart-lung machine Open-heart surgery, heart and lung transplants - these wouldn't have been possible today without the creation of the heart-lung machine, which takes over the jobs of these vital organs so surgeons can get down to business.

It is the most important surgical development this century, says Dr. Bruce Gewertz, chairman of surgery at the University of Chicago.

As a surgical resident, Dr. John "Jack" Gibbon developed the first heart-lung console. He spent years perfecting his invention before using it to repair a hole in a woman's heart in 1953 at Thomas Jefferson University Hospital in Philadelphia.

Here's how it works: The blood is taken by tubes inserted into the main veins leading to the heart and it's pumped through the oxygenator, which is like an artificial lung.

The oxygenator feeds oxygen to the blood and takes out carbon dioxide.

The freshly oxygenated blood is returned to the body through tubes inserted into the aorta (the main artery carrying blood from the heart) or into a large artery in the leg.

This means the heart can be stopped and the surgeon can operate in a blood-free zone.

Fourteen years later, in 1967, Dr. Christian Barnard used the machine during the first heart transplant, performed in Cape Town, South Africa.

These days, surgeons at Lutheran General Hospital in Park Ridge are performing coronary bypass surgery without a heart-lung machine. The new method lets surgeons attach grafts to the arteries without stopping the entire heart.

A vaccine to stop polio A dreaded disease in the first half of the century, paralytic poliomyelitis - better known as polio - is virtually unheard of in the United States today.

The credit lies largely with Dr. Jonas Salk, who discovered the first polio vaccine, deemed effective in 1955. It was a momentous development in the field of preventative medicine, said Dr. Dorothy Lane, who chairs the American Board of Preventive Medicine.

Polio "was the AIDS of the '50s. And then ... one man delivered us," Life magazine wrote in 1990.

Salk used the "killed" form of the polio virus to create an injectable vaccine, which rallied people's natural defenses without making them sick.

Before the vaccine, polio struck thousands of Americans, mostly young children, each year.

In serious cases, the virus attacked the central nervous system, killing some and leaving others confined to iron lungs or leg braces.

Millions of Americans remember stern warnings from their parents to stay out of the water for fear of catching the crippling virus.

"There were bad epidemics in the '40s," Lane said. "The vaccine saved countless lives."

Treating dehydration For many people, diarrhea is nothing more than a nuisance - an unpleasant side effect of illness.

But diarrhea and its dehydrating effects on the body can be deadly, especially in young children.

It kills about 4 million people in developing countries each year, according to the Centers for Disease Control and Prevention.

In the United States, 9 percent of all hospitalizations of children under 5 years old are associated with diarrhea, and 300 to 500 children die annually from this preventable condition.

A death toll isn't higher because of oral rehydration therapy, says Dr. Benjamin Wilfond, a pediatrician with the National Institutes of Health. It's his choice as the century's top advance in pediatrics.

Oral rehydration therapy sounds more complicated than it is.

A simple mix of water, salts and carbohydrates, the therapy prevents dehydration in children at risk of losing too much fluid from diarrhea or vomiting.

It came about in the late '60s to help children in developing countries, where diarrhea-producing diseases can run rampant.

Even in the United States, parents today often keep on hand a bottle of Pedialyte or similar solution to keep their little ones from getting dehydrated if they become ill.

"It really has made a dramatic improvement," Wilfond said.

'A new era' with lithium Suffered by millions of Americans, bipolar disorder, or manic depression, is a mental illness that causes massive mood swings between the pits of depression and the heights of mania.

"It's a devastating illness," said Dr. Stephen B. Shanfield, psychiatry professor at the University of Texas Health Science Center in San Antonio. "It causes people who are very competent to lose their judgment, make bad decisions and alienate the people around them."

Sometimes, it leads to suicide.

But that's less common these days, largely thanks to lithium - Shanfield's choice for the most significant advance in psychiatry.

The drug helps stabilize the wild euphoria and overwhelming depression that are the hallmarks of manic depression.

"It revolutionized the treatment of bipolar patients," Shanfield said.

Before the advent of lithium in the '50s, bipolar disorder "was treated nonspecifically - just like any other psychosis - with sedatives and all the other things they used to treat people with before they came up with these powerful psychiatric medications," Shanfield said.

Between 1960 and 1970, lithium caught on as the best treatment out there.

"A new era had indeed dawned for manic-depressive patients," wrote Dr. Mogens Schou, in a 1997 article in the Archives of General Psychiatry.

'The pill' Birth control would never be the same again.

In 1960, the Food and Drug Administration gave the OK for the Skokie-based pharmaceutical company Searle to launch the first oral contraceptive, which would come to be known as "the pill."

"It liberated women," said Dr. Warren Pearse, former executive director of the American College of Obstetricians & Gynecologists and current editor of the journal Women's Health Issues.

"The options before that were condoms, which you had to sneak out to buy, or diaphragms and jelly, which didn't work all that well," Pearse said.

The pill works by interfering with the body's natural hormone production to prevent ovulation, meaning eggs aren't developed and released from the ovaries.

Forty years later, today's birth control pill is pretty different than its predecessor.

The original pill contained about five times more estrogen and 10 times more progesterone than today's versions. With the modern pill, you're less likely to feel morning sickness-like nausea and bloating than you would have taking the pill 40 years ago. More extreme side effects such as blood clots are rarer these days, too.

Better cataract surgery Imagine being confined to bed for two weeks with your eyes patched and sandbags around your head to keep it steady while your wounds healed.

That was the fate that befell many cataract patients in the first part of the century.

"It wasn't acceptable by today's standards," said Dr. William Tasman, president of the American Academy of Ophthalmology. "If the recovery was satisfactory, they had to wear very thick glasses that limited peripheral vision. If you only had one eye done, it was tough to coordinate both eyes. That persisted really into the '50s and in some cases into the '60s."

Cataracts are incredibly common in older adults. They occur when the lens of the eye becomes cloudy, making it difficult for light to reach the retina. Vision becomes increasingly blurry.

Cataract surgery these days is a far cry from its predecessor.

A precise instrument cuts the upper edge of the cornea. Part of the defective lens is taken out and replaced with an intraocular lens. The cut is sewn up with a fine nylon thread measuring half the diameter of a human hair.

Tasman said the use of the intraocular lenses in cataract surgery is the century's premiere development in the field of ophthalmology.

"Now people are in and out the same day," Tasman said.

He said much of the credit for the intraocular lens lies with an Englishman named Harold Ridley. During World War II, Ridley treated pilots whose canopies had been blown off. Fragments lodged in their eyes. He noted how well that material was tolerated and came up with the idea for an implantable lens.

"They were called Ridley implants," Tasman said. "They fell into disrepute for a while, but technology advanced and made them more refined. Now, they're the way to go."

Emergency medicine It's hard to believe that less than 50 years ago, emergency departments were a rarity in hospitals.

"If somebody got really sick, they saw their family doctor," said Dr. William G. Barsan, president of the American Board of Emergency Medicine, which is celebrating its 20th birthday this year. "If they showed up at a hospital emergency room, typically there would be no doctors on duty."

And if they were on duty, they weren't trained in emergency medicine.

An internist, for instance, would be fine if you had a heart attack or pneumonia, but you might be out of luck if you wrecked your knee or injured an eye.

Part of the reason Barsan became an ER doc himself dates back to 1967, when he was a high school senior.

"My very best friend was killed in an automobile accident," Barsan said. "At that time, in northern Ohio, there were no paramedics or people like that. Most ambulances were station wagons or hearses often run by funeral home directors.

"Once he got to the hospital, there probably weren't any doctors in the emergency department. These days, there would be trained paramedics dispatched within 10 minutes of the accident. Or maybe there'd be an air medical helicopter team who could deliver life-saving treatment at the scene."

Hospitals in the '60s began to realize they needed to train doctors specifically for emergencies.

That led to the first emergency medicine training program at the University of Cincinnati in 1970.

By 1979, the number of training programs had blossomed to 15, and the practice gained official recognition as its own specialty.

Antibiotics Pneumonia and other bacterial infections used to be a death sentence for many children in the early part of the century.

"You couldn't really do anything for some of these children," said Dr. Lanny Copeland, president of the American Academy of Family Physicians. "Nurses used to just rub them down with oil of wintergreen. It may have made them feel a little better, but it certainly didn't do anything to the illness."

Those were the days before one of medicine's most powerful tools - antibiotics - emerged on the medical scene.

Antibiotics help fight infection when the body has been invaded by dangerous bacteria or if bacteria already in the body starts to multiply uncontrollably.

The first group in a long line of antibiotic drugs was penicillin, discovered in 1928 and made into a drug a dozen years later. It's used to treat a wide range of infections, from tonsillitis to gonorrhea.

"We can treat infectious diseases so easily now, and they used to be fatal," Copeland said. "We take it for granted that we've always had antibiotics around, but it's only 50 or 60 years ago that we didn't."

Turns out you can have too much of a good thing.

Antibiotics have become so commonplace, we're developing a resistance to some of the drugs.

"We're going to have to decrease our usage and research new antibiotics to fight bacteria," Copeland said.

Fluoride in water The main reason tooth decay is less common today in the United States isn't due to newfangled toothbrushes and fancy toothpastes.

It's due to something much more mundane: water.

Adding fluoride to community water supplies - a trend that started shortly after World War II - has worked wonders in warding off tooth decay, especially in children.

"It hardens the enamel surface of your tooth so it's less susceptible to tooth decay," said Dr. Tim Rose, president of the American Dental Association. "It's cut the decay rate in most children by more than 60 percent."

While most dentists and health professionals sing its praises, the fluoridation of public water supplies has whipped up a storm of controversy.

Some people claim it causes cancer - an accusation staunchly refuted by the ADA, among others.

Still, not all communities have seen to it that their water supplies have the recommended levels of fluoride. Los Angeles came on board as late as last year.

"We still have pockets of kids with problems who live in areas that don't have fluoridated water," Rose said.

Smears to analyze cells Whether it's scraping the cervix with a small brush or using an endoscopic device to reach the intestines, smears gather the cells needed for pathologists to make accurate diagnoses.

"It makes the cells of the human body much more accessible to pathologists," said Dr. Nelson Fausto, editor in chief of the American Journal of Pathology.

Take the most famous of the so-called smears, the Pap smear.

Dr. George Papanicolaou - for whom the Pap smear is named - spotted some unusual cell formations while looking through a microscope at tissue from the cervix.

The presence of these abnormal cells turned out to be an excellent predictor of cervical cancer, which used to be the leading cause of cancer deaths in American women.

Since the Pap smear became routine in the '50s, cervical cancer deaths in the United States have plummeted by 70 percent.

Cervical smears also can detect viral infections such as herpes, and they can gauge the level of hormones in the body.

Used to collect cells from other parts of the body, such as the lungs and intestines, smears have evolved into an invaluable tool for pathologists, who study all aspects of disease - from its causes to its effects on the body.

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