Surgery with Femtosecond Lasers

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Surgery with Femtosecond Lasers

Posted by michael on Wednesday April 23, 2003 @08:56AM from the fast-popcorn dept.

An anonymous reader writes "Science Daily has an article on femtosecond lasers, which emit pulses of light that are a billion times shorter than an electronic camera flash and how they are currently being used in LASIK procedures."

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Hmm, how fast is an electronic camera flash... by amorsen · 2003-04-23 09:00 · Score: 1

Quick calculation...
1 microsecond (assuming US billions).

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1. Re:Hmm, how fast is an electronic camera flash... by GigsVT · 2003-04-23 09:06 · Score: 4, Funny
  
  not really, more like a few milliseconds
  
  I guess we should really come up with some standard system for measurement in news articles, the JI (Journalist Idiots) System of measurement.
  
  Time - camera flashs
  Small physical size - human hairs
  Large information - Library of congresses
  Meteor size - VW Bugs
  
  Any more?
  
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2. Re:Hmm, how fast is an electronic camera flash... by PD · 2003-04-23 09:24 · Score: 3, Funny
  
  Height: Empire state buildings. eg. if you stacked a quadrillion pennies they would be X times the height of the Empire State building.
  
  Height 2: Earth-Moon. eg. if you stacked a quadrillion cases of beer, they would reach X% of the way from the Earth to the Moon.
  
  Accuracy: Amazing Hole in One. eg. NASA's space probe reached Saturn only 4 microseconds late. That's like sinking a Hole in One from X billion miles.
  
  Length: Earth circumferences. eg. If you laid all the fiber in the world end-to-end it would stretch around the globe X dozen times.
  
  Volume: Olympic Swimming Pools. eg. a million cases of beer would fill X Olympic Swimming Pools.
  
  Then, there's the famous nanoseconds that Grace Hopper used to pass out. They were little pieces of wire an inch(?) long that represented the distance light travels in 1 nanosecond.
  
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3. Re:Hmm, how fast is an electronic camera flash... by PD · 2003-04-23 09:28 · Score: 1
  
  Thought of some more that I see a lot:
  
  Power: Light Bulbs. eg. The amount of electricity produced in a second by the Hoover Dam would light X light bulbs for a year.
  
  Computer Benchmark: Calculators. eg. It would take a person with a calculator X millions of years to do what this new supercomputer can do in a second.
  
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  If tits were wings it'd be flying around.
4. Re:Hmm, how fast is an electronic camera flash... by misophist · 2003-04-23 10:11 · Score: 2, Informative
  
  Light travels about a foot per nanosecond.
5. Re:Hmm, how fast is an electronic camera flash... by Lord+Sauron · 2003-04-23 12:01 · Score: 1
  
  Bandwidth - DVD's or mp3, according to scale
  Time - Average days between /. duped articles
6. Re:Hmm, how fast is an electronic camera flash... by Anonymous Coward · 2003-04-23 12:08 · Score: 0
  
  No, it doesn't. It's much closer to an inch.
7. Re:Hmm, how fast is an electronic camera flash... by cicadia · 2003-04-23 12:13 · Score: 1
  
  No, it's actually very close to a foot. (c ~= 29.9 cm / ns)
  
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8. Re:Hmm, how fast is an electronic camera flash... by SomeGuyFromCA · 2003-04-23 13:50 · Score: 3, Funny
  
  Burner speed: older burners. "This fast burner is the equivalent of 40 burners!" Used mainly by the RIAA.
  
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9. Re:Hmm, how fast is an electronic camera flash... by Anonymous Coward · 2003-04-23 15:56 · Score: 0
  
  I'm the guy who modded you up. Yes, you're quite right, 0.299792458 metres.
10. Re:Hmm, how fast is an electronic camera flash... by Anonymous Coward · 2003-04-23 15:58 · Score: 0
  
  I really shouldn't have done that, should I. Doh.
  
  -- The guy who modded you up.
11. Re:Hmm, how fast is an electronic camera flash... by GnarlyNome · 2003-04-23 18:56 · Score: 0
  
  As fast as light is it is still slower than a Politican grabbing the credit
  
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12. Re:Hmm, how fast is an electronic camera flash... by 3waygeek · 2003-04-24 05:40 · Score: 1
  
  Then, there's the famous nanoseconds that Grace Hopper used to pass out. They were little pieces of wire an inch(?) long that represented the distance light travels in 1 nanosecond.
  
  More like 1 foot. The speed of light in vacuo is almost exactly 3E8 m/s, so in 1 ns, it'd travel 0.3 meters (1 foot is 0.3048 m).
13. Re:Hmm, how fast is an electronic camera flash... by Anonymous Coward · 2003-04-24 08:43 · Score: 0
  
  How can u forget the stupid "football fields" and
  "size of texas" measure for area? also "mother of all bombs" - does this bomb lay eggs, hatch them and give birth to smaller bombs? it shud be more like - king of all bombs.
Why would anyone want to do this? by jonm · 2003-04-23 09:03 · Score: 2, Funny

I write in pure HTML - why would anyone want to do otherwise? Oh hang on - wrong thread!
A few questions... by sciwhiz007 · 2003-04-23 09:08 · Score: 1
Hmm, I have a few questions or concerns regarding this new technique:
- Are there any side-effects to this new treatment?
- How much more does it cost to the end user?
- How much does it cost to implement this new technology?
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jeeze... by nomel · 2003-04-23 11:34 · Score: 2, Funny

They would get a lot more done if they left the laser on longer.
1. Re:jeeze... by Vellmont · 2003-04-23 13:09 · Score: 2, Informative
  
  The article doesn't mention why ultra-short duration lasers are so much more attractive for surgery. The reason is that one of the problems with lasers is they heat the area around what you're trying to remove, and thus damage it and make imprecise cuts. Femto second lasers have such a short duration that there's not enough time to heat the surrounding area.
  
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Do more research when considering eye surgury. by slacy · 2003-04-23 12:05 · Score: 4, Insightful

Almost everyone I've ever talked with who's gotten laser eye surgury has been disappointed with the results. They all say:
"My doctor told me that my vision would be better than what I see with my contacts in. Its not. Its worse than it was before, but at least I don't have to deal with contacts. They say I can stop using these eye drops after a couple of months."
Well, to me, that sounds like a pretty sorry tradeoff. Don't waste your vision on convenience! Find several people who have had the procedure, and ask them how satisfied they are, if they have to wear glasses (most still do for reading) and if there were other side effects.
1. Re:Do more research when considering eye surgury. by Blaine+Hilton · 2003-04-23 13:11 · Score: 1
  
  I believe the success of such an operation is largly determined by the skill of the doctor, some are just newbies.
2. Re:Do more research when considering eye surgury. by mOdQuArK! · 2003-04-26 05:44 · Score: 1
  
  Almost everyone I've ever talked with who's gotten laser eye surgury has been disappointed with the results.
  
  Really? My (two) relatives who got such surgery rave about how wonderful the results were. Of course, their eyesight before the surgery was so bad that you could've probably done the surgery using sandpaper & ended up with an improvement, but they're definitely happy with the results.
  
  Unfortunately, I'm only slightly nearsighted, so it wouldn't really be worth it for me to have such work done.
Microkeratome by sazim · 2003-04-23 13:56 · Score: 5, Interesting

I had LASIK surgery on both eyes in 1997. I had -6.5 (diopters ?) in both eyes (very short sighted) and came out of the operation with 40/20 vision (better than 20/20) in both eyes.

A microkeratome (razor) was used to create the "flap". They told me that it was this device that was the "weak" link in the entire procedure as it could get stuck or could cut slightly wrong, as mentioned in the article. As the surgery is done while awake (both patient and surgeon), I was relieved when told that the microkeratome had cut successfully. I was lucky and have no complaints: I had to use several eye drops for 3 months during which time my vision was *slightly* hazy (at night) but nothing after that.

One of my eyes has become slightly astigmatic (natural process) and I am considering another LASIK procedure as it is now several generations on from my previous surgery. Good to know that the microkeratome is possibly on the way out.

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1. Re:Microkeratome by Stranger4U · 2003-04-24 08:23 · Score: 1
  
  Unless you've got your numbers backwards, 40/20 vision isn't better than 20/20, it's worse. 40/20 means what most people can see at 40 feet, you can only see at 20 feet. It's still better than what you started with, but not better than "average" vision.
2. Re:Microkeratome by bugnuts · 2003-04-24 10:25 · Score: 2, Informative
  
  No, you're wrong... that's 20/40 vision.
  
  40/20 vision is GREAT vision... you can read at 40 feet what "normal" people can see only at 20 feet.
You can see the intralase procedure at work.... by deglr6328 · 2003-04-23 18:12 · Score: 2, Interesting

...right here(scroll down to the bottom for mpeg)[warning! not for the squeamish!].

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Best money I've ever spent by sjbe · 2003-04-24 09:01 · Score: 3, Interesting

Almost everyone I've ever talked with who's gotten laser eye surgury has been disappointed with the results.

As someone who had LASIK, I can tell you that I am ecstatic with the results. I have essentially 20/20 vision in both eyes and do not need to wear glasses for anything. That makes it worth every penny. Yes my eyes were a bit dry afterwards, but that had as much to do with staring at computer screens for 8+ hours daily than the surgery. When I was off work my eyes were fine.

Now that said, it isn't for everyone. If you are comfortable with glasses and don't have a compelling reason to have the surgery besides annoyance, you might not want it. It is a risk after all. In my case I'm an athlete (yes they do exist on slashdot) so it was valuable to me to not have to wear glasses.

Anyway I'm thrilled with the results but recommend that anyone thinking of getting the surgery research it very carefully. It's not something to be taken lightly and I'm glad I didn't.