It's disturbing to show up for Lasik eye surgery and to be greeted by someone who appears to be blind.

Dark shades, erect posture, unmoving head, the man sits calmly in the waiting room. Clearly he has just had the surgery. Eventually I get up my nerve to ask: "How did it go?"

"Fine," he answers serenely. Later I will learn the secret to his zombie calm.

I have dithered for years over Lasik surgery, asking my ophthalmologist his opinion (he's against it), checking Web sites, questioning eye experts and patients when I meet them. I believe myself to be a prime candidate. Nearsighted since the age of 10, I hate glasses, see poorly with soft contact lenses and cannot tolerate the hard lenses that offer the crispest vision.

But I have heard the tales of Lasik patients who wind up with fuzzy vision that can't be corrected with glasses or contact lenses, who can't drive at night, and worse. And so I waited.

Then I heard about the new technology called WaveFront, or custom Lasik. It uses a computer and a machine that bounces light off the retina to map the cornea precisely; this provides guidance for the laser that reshapes the cornea to correct the vision.

While ads for the new technology make it sound like a revolution, a closer reading reveals that the mapping only reduces, but doesn't eliminate, the risk of some serious side effects of the surgery, like double vision, halos and glare that can be so bad it prohibits nighttime driving.

Two years after WaveFront's introduction, I made an appointment. Though I hadn't signed up for the surgery yet, I paid nothing. I had to peer, without really focusing, at what looked like a video game image of a road stretching into the distance. This was harder than it sounded. Meanwhile, the WaveFront scanner bounced light off my retinas.

The technicians also measured my pupil size and the thickness of my corneas. People with big pupils or thin corneas have a higher risk of poor outcomes.

At the end, the optometrist told me I was a good candidate but warned it would hurt and I would still need glasses for reading. Still, I waited.

A Navy Rescue

Each company seeking approval for its WaveFront machine submitted to the Food and Drug Administration (FDA) its own studies, carefully selected to highlight the benefits. Most showed that 85 to 95 percent of patients come out with 20/20 vision or better.

One of the few independent studies, done by a team at Ramathibodi Hospital School of Medicine in Bangkok, involved 11 patients who got standard Lasik on one eye and WaveFront on the other. Researchers found virtually no difference in the rate of higher-order aberrations such as halos or double vision. A team assessing Lasik for the American Academy of Ophthalmology in 2002 did not find one company's laser better than another's. But all met the minimum FDA requirements of giving 80 percent of patients 20/40 vision or better.

In May, I learned that the U.S. Navy had done a clinical study of custom Lasik and claimed a nearly perfect record of success. Capt. Steve Schallhorn, director of cornea and refractive surgery at the Navy Medical Center in San Diego, explained that with conventional Lasik, 88 percent of patients he treated had 20/20 vision or better six months later, and 30 percent saw halos or had other night driving problems.

With custom Lasik, 97 percent of 34 patients he treated had 20/20 vision and none reported any nighttime symptoms. Schallhorn has studied more patients since then and said the numbers hold up.

"We don't have 100 percent 20/20. Probably with custom surgery we routinely get about 95 percent," he said in a telephone interview. "There are two caveats. The people that we treat are generally very, very healthy. They are in the military. And they have relatively low levels of nearsightedness."

His patients usually have about three diopters of myopia, meaning their correction is minus-3. Mine was minus-4.5, which means my vision is about 20/600. I am so blind without my contacts that I once made everyone get out of a swimming pool when I lost a lens and searched the bottom until I found it. Otherwise I could not have driven home.

"We don't do aviators or divers because of lingering concerns about the effects of Lasik," Schallhorn added. It is not clear how a cut cornea will withstand the low-oxygen, low-pressure conditions seen in cockpits and deep underwater, he said.

Experts say not everyone needs the new technology. WaveFront costs about $5,000 for both eyes (those "$495 per eye" come-on ads notwithstanding). Standard Lasik is about $1,000 cheaper.

But what if you decide to save the money and get the standard surgery, and then end up with halos at night or the side effect called reduced contrast, which can make faces indistinct when backlit? You wouldn't know if bad luck or your cheapness was to blame.

I decide to spring for the newer technology.

WaveFront and Me

On the day of the procedure, an optometrist comes to collect me from the waiting room. It's clear why this is such an expensive deal -- there's a cast of thousands here. I get a final cursory exam and am offered a Valium. I decline. (Bad decision. More on this later.)

The surgeon enters. Here is the man whose hands have restored the vision of very, very famous golfers and tennis players. He is disappointingly lacking in charisma. He glances quickly at my chart and asks if I have any questions. He answers them curtly.

Next I am led to the laser suite, where a young, strong technician eases me into the chair, which positions me on my back with my head pointed slightly downward. He positions a bulky apparatus over my face and puts numbing drops into my right eye. In a flash my left eye is bandaged shut. The surgeon comes in and hooks an eyelid holder over the upper and lower lids of my right eye.

Wait! I think. But there is no pausing here -- not on a morning where I am patient number 29 out of 30 and everyone is ready to leave for the weekend at lunchtime.

Then the microkeratome, the bladed tool that will slice my corneas, is fitted. It works like a little guillotine, with a blade that slices a round flap out of the cornea. This is one of the most fretted-about parts of Lasik, with some experts arguing that if a patient's cornea is too thin, or if the flap is cut too thickly, there is little to work with if more surgery is needed later.

This definitely does not feel good. "A little pressure," I am told. Then everything goes black. I feel nauseated. I fight the urge to flee. Why didn't I take that Valium?

Within seconds, the light returns. I know my cornea has been cut and flipped open, but it does not hurt.

Most of the serious complications of Lasik come from this cutting of the flap -- either it wrinkles when it is replaced, or it becomes infected, or the body responds to the incision by growing layers of cells that blur the vision. These risk are the same for WaveFront and regular Lasik.

The laser begins clicking. I see nothing but the blurry spot of light that I have been told to focus on from the beginning. The laser's cool ultraviolet light, guided by the information on a floppy disk carrying my personal WaveFront prescription, has its way with my cornea.

Thirty seconds later it is over. The surgeon whips off the equipment and wipes my eye. He is surprisingly rough. Ten minutes later the second eye is done. "Look at the clock," the surgeon commands. I can see that it's 2:30. I can see the clock! Without glasses! "Congratulations," the surgeon says and shakes my hand. I am escorted to the recovery chair and left alone.

My vision is foggy, as if I had water in my eyes, but I can see close up and far away. I am given two Tylenol PMs and examined briefly by a brusque optometrist. I ask her how bad the pain will be. "There will be pain," she says, offering no sympathy.

I feel sleepy when my husband drives me home. Is it the Tylenol PM? The stress of the surgery? I suspect both. Now I know why Mr. Zombie looked that way. I climb into bed and have no trouble falling asleep, as instructed, for the afternoon. When I awake there is a stabbing pain, but it disappears quickly.

20/60 Hindsight

The next morning I am able to drive myself to my appointment. Without glasses.

A technician checks my eyes. I can see the eye chart and make out the letters near the bottom, although they are not crisp. "You're 20/20," he declares. An optometrist explains that my vision will be unstable for a few days and that it is too soon to say what my final vision outcome will be. She cheerfully advises me to keep my eyes wet with drops.

I work that night, sitting eight hours at a computer screen. Although I need to put in drops regularly, I can see to read, without glasses, for the first time in years. I drive home after dark and notice the lights look a bit large and bright, but not enough to be distracting.

But within a week my already-soft vision is softening more. My eyes feel uncomfortably tight and dry at times. At a checkup 10 days later the optometrist confirms my fears. "Your corneas are steepening," he says.

In other words, my corneas are reverting to the football shape that made me myopic in the first place. I am now 20/50 in one eye and 20/60 in the other. He assures me this can be corrected with a little "enhancement." That means having the flap lifted -- it will not have healed fully -- and having the laser shave off a little more cornea. He wants to wait three months because there is a "slim" chance my vision will improve.

In the meantime he writes me a prescription for glasses -- glasses! -- so I can legally drive. I decide not to fill the prescription.

Later, I decide to visit www.surgicaleyes.org, a Web site run by people who have had bad experiences with Lasik. I am very glad I did not look at this site before getting the surgery. It features photographs of blurry rooms, blazing headlights that obscure the road, eye charts where the letters are doubled.

"I was unable to read a newspaper or drive at night and whatever my optometrist did he could not correct my vision with prescription lenses," one patient is quoted anonymously on the site. "Basically I was seeing seven multiple images."

Will the new technology reduce such horror stories?

"The problems of people that come onto SurgicalEyes are not things that are necessarily going to be solved by WaveFront," said David Hartzok, a Pennsylvania ophthalmologist who is executive director of the site, in a phone interview.

"When you lift and cut the flap and then lay the flap back down, you may be altering the topography of that cornea," he added. The WaveFront technology may make the laser change the cornea more precisely, but the problems associated with Lasik, he said, often have to do with how the cornea heals.

"We do know that we have people coming on our site that have had custom WaveFront treatments and still have some of the complaints than they had before." Lasik, he said, is very much subject to hype.

It turns out that choosing, not treating, patients is the key to Lasik success. "My old corneal prof used to say you can teach a monkey how to do eye surgery," Leo Maguire of the Mayo Clinic in Rochester, Minn., wrote in an e-mail. "The brains are used in preoperative selection and postoperative management."

Still, most people are happy with Lasik, Maguire said.

"Refractive surgery has the highest patient satisfaction rates and highest quality-of-life improvement scores of any operation that is done," Maguire said.

"It does not change the reality that some people have things go wrong from any number of causes including, but not limited to, poor patient selection, machine malfunctions, surgeon error and poor wound healing. These rare things can happen after custom laser just like they can after standard laser."

A month after the surgery I am still slightly nearsighted -- about 20/30 in one eye and 20/50 in the other. Several optometrists tell me this is not unusual. The optometrist at my one-month checkup tells me they'll adjust their WaveFront logarithms for 45-year-old women to take my case into account -- a small comfort.

We talk about the possibility of having enhancement surgery on one or both eyes. If I do both, I'll have crisp distance vision but will need reading glasses. Doing one eye will give me "monovision" and allow me to read with one eye and use the other for focusing in the distance. I should think about this for three months while my vision stabilizes, he advises.

Some days my vision seems very clear and on others I am starting to have trouble reading. I have an eye gel that wets my eyes better than the drops, so the dry discomfort is gone. Can I live with that?

The other night I finished a book in bed and reached up to pull off my glasses. They weren't there.

I think I can live with it.

*

A Closer Look at Lasik

For more information:

* www.surgicaleyes.com

* American Academy of Ophthalmology, www.aao.org

* American Society of Cataract and Refractive Surgery, www.ascrs.org

* International Society of Refractive Surgery, www.LocateAnEyeDoc.com

* National Eye Institute, www.nei.nih.gov

Maggie Fox is a Washington-based health reporter.

After years of waiting for technology to improve, author Maggie Fox (top) got WaveFront Lasik surgery. The method uses a computer and a machine that bounces light off the retina to create a map of the cornea. This map (shown as a virtual image hovering over the iris in the illustration, above) guides the laser that reshapes the cornea to correct vision. The technique is said to reduce some bad outcomes. A computer-generated three-dimensional map of the cornea is supposed to reduce -- but not necessarily eliminate -- the risk of some serious side effects of Lasik surgery, including double vision, halos and glare.