Surgery for sinus misery: Better, but still no cure

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Surgery for sinus misery: Better, but still no cure

Assisted by scrub nurse Judy Curtis, Dr. Ralph Metson of Massachusetts Eye and Ear Infirmary performs sinus surgery on Nancy Butler with the aid of a miniature camera that shows the patient's sinus passages and the location of his tiny instruments.
Surgeon Ralph Metson stares at a big video screen that shows, with amazing clarity, the inside of Nancy Butler's nasal passages.

A weird glow lights up her nose and cheek from within. It comes from the fiber-optic tip of Metson's endoscope, which also holds a high-res camera lens.

On the monitor, you can see the miniature instruments he's using to cut away inflamed tissue and snip away pieces of eggshell-thin bone that block Butler's sinuses and give her nonstop headaches.

To avoid poking through to the brain or into the orbit of an eye, there's a device around the patient's head with a guidance system that tells Metson, in three dimensions, exactly where his sharp instruments are on a CT scan of Butler's head.

After an hour or so of this delicate work, Metson has opened up the 72-year-old woman's sinuses so they can drain. “The next time she gets a cold,” he says, “her membranes are not going to swell and block the sinuses the way they have in the past. They're going to stay open.”

This is modern sinus surgery. It's a lot less brutal than the old days — back in the early 1980s. Then, surgeons cut through the face and mouth, scraped out the sinuses and left patients bruised and scarred. Often they were no better off, sometimes worse.

Advances since then have persuaded more doctors to do sinus surgery. So a lot more people are getting it — around 300,000 a year, making it one of the most common operations.

But how good is it, in terms of giving patients relief from the pain, breathing difficulty and fatigue of chronic sinusitis? “Surgery is usually not curative,” Metson says. “But probably in over 90 percent of the cases, it does significantly improve a patient's quality of life. He or she will still have infections after surgery. But hopefully they'll be less frequent, less severe and shorter in duration. A brief course of antibiotics will work better after surgery.”

Judy Foreman, another of Metson's patients, offers an example of both how surgery can help — and why patients' expectations shouldn't be too high.

Foreman had sinus surgery two years ago, when she was 64, after trying everything else. She rinsed out her sinuses faithfully with saltwater. She tried decongestants, antihistamines and steroid nasal sprays. Over and over, Metson prescribed antibiotics.

Surgery may be less debilitating than it once was, but it’s still the last resort for most people suffering from sinus problems. Here are three simpler treatments that may offer sinus relief.

Nasal irrigation, also known as nasal douche or nasal lavage, is one option. The idea is to rinse the sinuses with saltwater. The easiest way is with a bulb syringe or neti pot, which looks like a small tea pot.

As the saline solution passes through one nostril and out the other, it clears mucus, dust and allergen particles from the sinus cavities.

The technique might seem peculiar, but it's nothing new. It likely originated from yoga traditions as a way to fight cold symptoms, but it went mainstream after a nod from Oprah.

Studies show that nasal irrigation seems to work. A 2009 review of research by The Cochrane Library found evidence that nasal irrigation with saltwater can relieve symptoms and can help as a complementary treatment for chronic rhinosinusitis.

Kits for nasal irrigation usually cost $10 to $20 and are sold in drugstores.

Another option is corticosteroid nasal sprays. According to the Mayo Clinic, corticosteroids imitate hormones and can help alleviate inflammation. However, the sprays seem to provide only temporary relief for most users.

A few small studies suggest that acupuncture may also benefit some people with sinus problems, but, as one study in the Journal of Alternative and Complementary Medicine indicated, more research is needed.

For about 80 percent of patients, these nonsurgical alternatives manage the problem adequately, Metson says. But Foreman was in the other 20 percent.

Foreman writes a health column for The Boston Globe and other newspapers, so she's an unusually well-informed patient. “I read an article about people feeling less tired all the time after having had surgery, and I thought, boy, I would really like that,” she says.

When she asked Metson about surgery, he said most people with her degree of sinus problems would have had it long before.

“I thought, OK, so I'm just being scared,“ Foreman says. She didn't like to think of someone sticking sharp instruments up her nose and cutting away delicate tissue. But when she overcame her squeamishness and finally had the operation, she found it wasn't nearly as bad as she thought it would be.

“It's uncomfortable,” she reports. “Afterwards you have these cotton wads up your nose and, of course, you can't breathe with all this stuff in your nose.” But she didn't hurt very much. “I was so glad to get it over with that I would say the pain was not bad at all.”

And the outcome? Now she has three or four sinus infections a year instead of five or more. They're not as bad as before. Still, she's disappointed.

“I'm not like a person without this problem,” she says. “I get a cold and I freak out because I know it's going to be there for three weeks. Other people get it and they're done in five days.” Foreman wrote a column about her surgery. Two years later, she's still getting e-mail from people asking whether they should have it.

“I say, 'Go for it!' Because I think it's made enough of a difference that I'm glad I did it,” Foreman says. She'd consider a second operation, but Metson says usually that's advised only for patients with nasal polyps that regrow — not a problem she has.

A CAT scan of patient Judy Foreman's sinuses shows obstructed sinus and nasal passages on the right side (her left) prior to sinus surgery. Metson says most of his patients do better than Foreman. But surgery rarely cures them. That's because surgery doesn't touch the root cause of chronic sinusitis.

Surgeons can cut away bone and membranes that block sinuses. But they can't stop the inflammation some people are prone to, and that inflammation can cause new obstructions.

To tackle that problem, researchers have discovered five genes involved in that inflammatory process. Metson hopes drugs will be developed to regulate those genes.

“And if we can use those as novel targets for, let's say, nasal sprays or medications, we may be able to treat people like Judy without surgery,” Metson says. “Or we'll do surgery and follow it up after surgery with these sprays.” That, he says, will be the next big advance in sinus treatment.

(Source: NPR)

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Gliese 581g: If there's life there, how will we know?

Last week (Sept. 29), a team of researchers announced the discovery of Gliese 581g, a rocky, roughly Earth-size planet in its parent star's so-called “habitable zone” — a just-right range that can allow liquid water to exist.

One of the planet's discoverers said in a briefing that the “chances of life on this planet are 100 percent.” To determine if this is true, researchers will have to scrutinize Gliese 581g from afar, searching its atmosphere for certain telltale molecules.

Gliese 581g isn't far from Earth in the great scheme of things — only 20.5 light-years or so. But that translates to about 120 trillion miles (194 trillion kilometers) — 500 million times farther away from us than the moon.

So human-built probes won't be getting out there anytime soon. But one way to look for life on Gliese 581g is to turn our radio telescopes toward the planet, searching for patterns in emissions of electromagnetic radiation.

Such patterns could indicate the presence of intelligent life, according to Seth Shostak of the SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, Calif.

The Gliese 581 star system has intrigued researchers for a while, so they've already taken a few looks. During SETI's Project Phoenix, which surveyed almost 1,000 star systems from 1995 to 2005, astronomers looked at Gliese 581 twice, Shostak said. “No signal was found during these observations,” he told SPACE.com.

Life doesn't have to be intelligent and advanced for astronomers to pick it up. Studying Gliese 581g's atmosphere, for example, could theoretically reveal the presence of organisms as simple as microbes.

This method assumes the alien planet has an atmosphere, likely a necessity for life to take hold. Gliese 581g's discoverers reported that the planet's gravity is probably strong enough to hold onto an atmosphere, but they didn't definitively detect one. “The first thing is, you've got to have an atmosphere,” said Bill Borucki of NASA's Ames Research Center, the science principal investigator for NASA's planet-hunting Kepler mission. “If there is one, then what's the composition of that atmosphere?” If astronomers detect the signatures of large, complicated compounds — like chlorofluorocarbons, which people have manufactured to use as refrigerants and propellants — life is likely, according to Borucki.

“You're looking for chemicals like that,” he told SPACE.com. “If they're there, somebody's making them.”

But other, simpler chemicals could also be strong evidence for life, as long as their ratios are right.

“Ideally, you'd be looking for a complement of compounds that normally don't exist in chemical equilibrium,” said Jon Jenkins of the SETI Institute, the analysis lead for the Kepler mission. As an example, both Jenkins and Borucki pointed to methane and oxygen.

“You typically don't have both gases present in significant quantities unless life is present,” Jenkins told SPACE.com. But scientists would have to be careful how they interpreted such information, he added, because we don't know much about how other planetary systems tick.

“Though scientists get excited about these discoveries just like the public does, we also tend to be pretty cautious,” Jenkins said.

So scanning Gliese 581g's atmosphere, if it has one, would give us a good idea if the planet harbors life or not. But it'll probably be a few decades before we can do this properly.

Astronomers have characterized the atmospheres of alien planets before. But those other worlds are bigger and much hotter, meaning they throw off lots of radiation for our instruments to pick up. Gliese 581g is relatively close to Earth, but its other traits make it a tough read.

It's only about three to four times as massive as Earth, for example, with an average surface temperature between minus 24 and minus 10 degrees Fahrenheit (minus 31 to minus 12 degrees Celsius).

“Because they are cool and small, planets like this are very difficult to study,” Jenkins said. “It's easier to detect something than to characterize it in detail.”

Jenkins said that Gliese 581g also apparently doesn't transit its parent star, meaning it doesn't cross in front of it from our perspective on Earth. Astronomers can learn a lot about a planet's atmosphere by studying starlight that passes through it — but this technique is likely not an option with Gliese 581g.

As a result, the tools astronomers currently have at their disposal likely can't determine what's in Gliese 581g's air, according to Borucki and Jenkins. So researchers will have to wait for new instruments to come into play.

One promising tool mentioned by Borucki, Jenkins and Shostak is NASA's proposed Terrestrial Planet Finder (TPF) mission, which would use an array of telescopes orbiting Earth to generate detailed images of alien planets.

TPF would employ advanced techniques to reduce the glare of the exoplanets' parent stars, allowing the mission to pick up faint radiation coming from planets. The mission could theoretically detect chemicals like methane and oxygen in the atmospheres of alien worlds such as Gliese 581g.

The TPF mission, however, is in limbo. It is currently unfunded, with no launch date set. So researchers will probably have to wait a while before they can see what Gliese 581g's atmosphere is made of.

Whenever TPF, or something like it, comes along, it may have a long list of planets to check out, Jenkins said.

“I would predict that (Gliese 581g) is just the tip of the iceberg,” he said. “Fifteen or 20 years ago, very few people thought we'd be discovering such extrasolar planets anytime soon. This find just shows how far we've come.”

(Source: csmonitor.com)

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Coffee, tea linked to lower risk of brain tumor

Coffee and tea lovers may have a decreased likelihood of developing the most common form of malignant brain tumor in adults, a new study suggests.

The findings, from a study of more than 500,000 European adults, add to evidence from a recent U.S. study linking higher coffee and tea intake to a lower risk of gliomas, a group of brain tumors that makes up about 80 percent of malignant brain cancers in adults.

It does not, however, prove that the beverages themselves confer the protection.

“This is all very preliminary,” said lead researcher Dominique Michaud, of Brown University in Providence, Rhode Island, and Imperial College London.

“This study shouldn't be the reason that anyone changes their coffee or tea intake.”

And even if coffee and tea have some direct effect on glioma risk, the impact would be small. Brain tumors in general are uncommon; in Europe, for instance, annual rates are estimated at between four and six cases per 100,000 women, and six to eight cases for every 100,000 men.

Overall, the odds that a person will develop a malignant (cancerous) brain tumor in his or her lifetime are less than 1 percent.

Still, Michaud said, if higher coffee and tea intake is somehow protective against glioma, that could give researchers insight into the causes of the tumors.

“Right now, we don't know much about what causes brain cancer,” she noted in an interview.

The findings, published in the American Journal of Clinical Nutrition, come from an ongoing study in 10 European countries investigating potential risk factors for cancer.

At the outset, 521,488 men and women between the ages of 25 and 70 completed detailed questionnaires on their medical history, diet, exercise habits, smoking and other lifestyle factors.

For their analysis, Michaud's team focused on more than 410,000 participants who were cancer-free at the outset and had complete dietary information.

Over an average of 8.5 years of follow-up, 343 of these men and women were diagnosed with glioma; another 245 were diagnosed with another, usually benign type of brain tumor called meningioma.

When the researchers divided the study participants into four to five groups based on their coffee and tea intake at the outset, they found no evidence of a “dose-response” relationship — that is, a decreasing glioma risk as coffee and tea consumption climbed.

The findings were different, however, when the researchers looked at two groups: those who averaged at least 3.5 ounces of coffee or tea per day, and those who drank less or none at all.

The heavier coffee/tea consumers were one-third less likely to be diagnosed with glioma, with factors such as age and smoking history taken into account. There was no connection seen with meningioma risk.

According to Michaud, it's not clear why there was no evidence of a dose-response association between coffee and tea intake and the risk of glioma — which is generally considered a stronger sign of a possible cause-and-effect relationship. But it may be related to difficulties in precisely measuring study participants' coffee and tea intake, which was dependent on self-reports.

It is biologically plausible that coffee and/or tea could affect glioma risk, Michaud said.

A recent lab study, for example, found that caffeine appeared to slow the growth of a type of glioma called glioblastoma. In addition, both coffee and tea contain antioxidants, which help protect body cells from damage that can lead to cancer and other diseases.

However, it's also possible that coffee and tea enthusiasts have other characteristics that might affect their likelihood of glioma development. Just what those characteristics might be is unknown, as the causes of most brain tumors are unknown. Researchers know of some risk factors. People who undergo radiation therapy — most commonly radiation of the head to treat other cancers — have a heightened risk of a future brain tumor. And genetic predisposition appears to play a role in a small percentage of brain tumors.

But the evidence on dietary or environmental factors, like on-the-job chemical exposures, has been inconclusive.

Michaud said that more research is needed both to confirm that there is an association between coffee and tea intake and glioma risk, and to understand the underlying reasons.

(Source: FoxNews)