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Registered Member #3040
Joined: Tue Jul 27 2010, 03:15PM
Location: South of London. UK
Posts: 237
Nicko wrote ...
Very interesting - 200+ spot welds at an average of just over 200mW / 532nm.
Good luck! Eye injuries/operations are one of the very few things that make me squirm, I've been in three times for minor eye injuries and that was bad enough. I wonder who was the first person who thought "I know lets try welding it with a laser" and who was the first mug they tried it on!
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
Another 410 pulses at 300mW and we seem to be there, for the left eye at least. Spot size was about 200uM apparently. Bad headache again + nausea, together with a throbbing eye - saw a total of 5 doctors today, all of whom took pleasure in sticking their fingers & nasty metal probes into my eyes... paracetamol is my friend...
The consultant doc says the power can go up to 800mW if needed. Bearing in mind that 300mW hurt me really badly, I hate to think what 800mW pulses feel like... hopefully, I'll never need to know...
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
ScotchTapeLord wrote ...
Nicko wrote ...
saw a total of 5 doctors today
Better than not seeing them! Hope the process continues to proceed successfully!
Just to draw a line on this - I've just been "signed off" by the consultants.
In February, I had surgery on the eye as the welds hadn't taken properly - interesting experience - the left eye was "blocked" - paralysed & then turned off - my right eye was still functioning - The last thing my left eye saw before going dark was a simply HUGE needle coming towards it ( ) . I then had over 1000 blasts at up to 800mW to finally weld the retina back down.
It damn well better stay stuck now because the next option is to cold-weld it from the back of the eyeball, and I really really don't want to go there...
All seems to be roughly ok now - I can play squash & tennis about as badly as I ever did - my depth perception has subtly changed and I have a dark shadow at the far left of my vision (which makes playing a fast moving ball out of the rear right corner of a squash court a bit of a challenge).
No more flashes or "floaters" (blood clots floating into the field of vision) now...
Registered Member #3610
Joined: Thu Jan 13 2011, 03:29AM
Location: Seattle, WA
Posts: 506
Isn't the argon green line 540 something? 532nm is the wavelength produced by the common frequency doubled YAG. Both YAG and pulsed argon lasers have been used in surgical applications, but I don't think argon is very common anymore since the solid state stuff is smaller and more efficient.
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
James wrote ...
Isn't the argon green line 540 something? 532nm is the wavelength produced by the common frequency doubled YAG. Both YAG and pulsed argon lasers have been used in surgical applications, but I don't think argon is very common anymore since the solid state stuff is smaller and more efficient.
Yes - originally they gave me the wrong info - its actually a Nd:YAG doubled to 532nm - pretty much a standard for retinopexy operations - its still green, which is why the surgeon originally told me it was argon - actually, that was a registrar, not the consultant - the consultant gave me the right info....
Registered Member #3766
Joined: Sun Mar 20 2011, 05:39AM
Location:
Posts: 624
Nicko wrote ... The last thing my left eye saw before going dark was a simply HUGE needle coming towards it ( ) . I then had over 1000 blasts at up to 800mW to finally weld the retina back down.
*shudder I would have demanded to be put under, my two biggest phobias are things near my eyes and needles...
Hope your eye gets better... gotta be kinda amazed at the fact that we can just go about welding retinas with lasers.
Registered Member #3610
Joined: Thu Jan 13 2011, 03:29AM
Location: Seattle, WA
Posts: 506
532nm is a very distinctive yucky lime green. I actually much prefer the emerald green argon line, but then I don't particularly want either one blasting my eyes!
I've got a couple of 543nm green HeNe lasers, that's a nice color too, and a bit strange to see coming out of a pink glowing plasma tube.
Isn't the argon green line 540 something? 532nm is the wavelength produced by the common frequency doubled YAG. Both YAG and pulsed argon lasers have been used in surgical applications, but I don't think argon is very common anymore since the solid state stuff is smaller and more efficient.
Yes - originally they gave me the wrong info - its actually a Nd:YAG doubled to 532nm - pretty much a standard for retinopexy operations - its still green, which is why the surgeon originally told me it was argon - actually, that was a registrar, not the consultant - the consultant gave me the right info....
Argon can come close with a 528nm line and a green 514.5nm line, so it could appear to be an argon, but pulsed argons are not very commercially used in surgery.
So yeah, I think you're right. It may be an Nd:YAG, or an Nd:YVO4, since either can be pulsed.
Registered Member #3271
Joined: Mon Oct 04 2010, 02:29AM
Location: Canada
Posts: 159
I got 71 pulses for a retina tear and I was told it was a pulsed Argon laser that was used. The doc worked at Lumonics Inc. (laser manufacturer in the 80-90s) in the field so I would assume he knew what he was using. The issue with doubled YAG is pulse to pulse repeatability. Although I have worked with both types of lasers I could not say (emergency procedure, several docs, frozen eye, stress, you name it) that I noticed the colour difference. It is important to recognise the symptoms and act promptly. They did treat it as an emergency once the symptoms were described.
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Just look into this laser...
