Smart Optical Fibers Could Save Lives

Roland Piquepaille writes "Lasers are now commonly used for surgery. With them, you can recover a better sense of vision. Or a tumor inside your body can be eliminated. But these laser light beams, which are currently enclosed inside optical fibers, can harm you if they escape from their enclosures. But now, according to Technology Review, MIT researchers have designed smart optical fibers which can monitor their status while the laser is doing its magic inside you and shut it down if a fiber wall is about to break. So far, the technology is only working in labs, but it could be used for medical applications in a few years."

Comments

A step forwards

[Anonymous Coward]

Personally I would have hoped they would already have a technology in place to stop lasers destroying vital parts of your body while in surgery.

How often does this happen?

[Gothmolly]

I mean, I know several people who've gotten LASIK surgery on their eyes, and its been around for years, yet I've never heard of a laser 'breaking' and damaging anything. Is this a solution looking for a problem?
I think self-monitoring fiber optics would be GREAT in the datacom industry... in the medical field its surely a 'nice to have'.

Re:How often does this happen?

[Hlewagastir]

AFAIK lasik doesn't make use of fiber optics, the application for this, as I understand it is the use of fiber optics to guide high intensity laser beams internally to attack tumors directly without the need for highly invasive, potentially dangerous surgeries. The problem with using fiber optics in the past, and the reason why this has not been done, is that fiber optic cables can fail, and "leak" the energy from the laser beam into other nearby organs, potentially causing grave damage. This development allows one to detect when a fiber optic cable is about to fail, and shut down the system before severe damage is done, allowing doctors to make use of a technology which was not previously available to them due to concerns about safety.

Incident Rate?

[JoeShmoe950]

With the current "unsmart" lasers, what is the rate of misses right now? have there been any dangerous or even fatal laser misses, and how much safety will this new method actually bring about?

Wow

[gcnaddict]

"can harm you if they escape from their enclosures ... if a fiber wall is about to break"

That possible? Gee, thanks for making me not want to have LASIK done on my eyes >_ Seriously, I hope this technology comes out of testing and into RWU (Real world use) very soon. If this kind of news leaks out, public paranoia will be all the rage :P

More information

[whitehatlurker]

More information appears in a PDF linked off of Fink's bio page. Apparently they use tin in the coating as the conductor. When that melts, the circuit breaks.

A little overstated...

[stoneymonster]

I work in the medical laser industry (as a software engineer, but I use the actual the devices all the time, and understand our hardware). We use a fiber laser. If the fiber were to break, the device would simply stop working.. because the fiber is clad in a metal armored jacket! I'm certain most delivery devices are similar. Part of the reason for this is you must maintain a minimum bend radius on the fiber, or it is very easy to exceed the total internal reflection constraints on it. The second thing is, our lasers have back reflection fault indicators, which also can go off if anything optically bad happens down the line. Anyone who knows of a medical device that has naked fiber being used to treat can feel free to correct me, but that sounds like a disaster waiting to happen for more reasons than the article states.

Re:A little overstated...

[frankmu]

i've used the KTP laser for laparoscopic ablation of endometriosis. these come with a flexible fiber you thread through a laparoscopy port. i don't think its a big deal most of the time. everyone in the room has eye protection when this thing is on, and the machine is on standby mode most of the time. i use CO2 mostly now. i am still VERY careful, so i won't burn myself or others. the CO2 laser is coupled to rigid tubing, so breakage isn't a big problem.

Re:A little overstated...

[mpoulton]

Anyone who knows of a medical device that has naked fiber being used to treat can feel free to correct me, but that sounds like a disaster waiting to happen for more reasons than the article states.

Most older general-purpose surgical lasers that I'm aware of use a naked fiber, and I do believe it is a disaster waiting to happen. I don't know about the new lasers coming on the market today, but I have worked with 80's and 90's vintage lasers still in service and they have no protection. For example, the Laserscope 800 is a 20W green (523nm) or 90W IR (1064nm) Q-switched CW YAG laser for general surgery. Its disposable delivery fiber is a 300 micron step-index core with no protection other than the bonded plastic jacket with a diameter of about 1mm. Cheap telecom fiber is better protected than this! The same system is used on the Trimedyne 1000 and the Lasersonics, both of which are 100 watt YAG lasers. I intentionally broke a fiber on my Trimedyne at full power, and was amazed by how dangerous it can be. The fiber can easily be kinked or broken by accident, which instantly results in a white-hot meltdown and separation at the point of damage. The broken end of the fiber then springs back and vaporizes or ignites whatever it flops against, potentially including nearby personnel. It also randomly radiates incomprehensible amounts of extremely dangerous invisible light in God knows what direction, likely frying the retinas of anyone foolish enough not to have excellent leak-proof goggles on. Considering how much they charge for these disposable delivery fibers, one would think some form of metal armor could be included to reduce the chance of damage.