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Myringoplasty & Tympanostomy Tube

C. Scott Brown, MD; David M. Kaylie, MD, MS
Duke University Medical Center

Transcription

CHAPTER 1

Alright, so this woman has eustachian tube dysfunction and has a globally retracted eardrum, and she's had 8 sets of tubes in the past. So what we're going to do is- I'll take a 6 speculum- is we're going to do a laser myringoplasty, which tightens the eardrum and allows the collagen that's all stretched out in the middle layer of the pars tensa to snap back to its native configuration. So - I'll take a curette. So we'll just get a good view of the eardrum.

So in clinic, when I saw her, her eardrum was retracted back onto the promontory, the entire eardrum. And when she Valsalva'd, it completely reinflated, so it was floppy and hyperinflated. And that gave her hearing loss because the eardrum isn't conducting sound properly. So what the laser will do is it'll tighten the eardrum back to its- native configuration.

Can we have an alligator?

What we can see- is this part of the eardrum is very floppy. And the fact that its anterior eardrum is retracted is a sign of eustachian tube dysfunction because that tells me that the- there's not getting air into the front- the anterior portion of the middle ear space.

So we'll go ahead and set the laser up. So the CO2 laser is particularly useful for this because- one of the molecules that the CO2 laser interacts with, other than water, is collagen, and it's called, it's chromophore. So it's a molecule that- a chromophore is molecule that a laser interacts with and is absorbed maximally.

Right. So that's the OmniGuide OTO-M fiber. So, CO2 laser's different than visible light.

CHAPTER 2

It's a very long wavelength and it can't be transmitted through a fiber like visible light, like KTP. So this is actually a hollow waveguide, it's not really a fiber. The internal- the- the internal portion of the fiber- or of the guide, is a mirror. And so as the laser bounces along, the way it's designed is the laser doesn't lose its energy as it gets to the tip. Because it- the way the multilayers of the fiber are designed that all light bounces off of it with virtually no loss of intensity. So what's going into the fibers- or the waveguide, is essentially what's coming out.

So- you extend it- out to there, and tighten it down.

Right, so it's- we set it at 2 watts for 100 ms pulse duration, so very low power. For a 100 ms pulse duration. Single pulse.

And so what we see- is the- eardrum right there, is- when the laser light goes off- see, that's a- it's hyperinflated.

Alright. So, first I'm going to test the laser. So can I have a- stick? Alright. So, does everyone have goggles? Alright, so… Alright, so, I'll say laser on, and then we'll turn it on, and then- alright, so- Good. Alright, standby.

Okay, so I'll turn her head away just a little bit, get- a good view of that- hyperinflated area.

CHAPTER 3

Alright. I'll take the laser. So, you want a diffuse- firing, you don't want it real close because that'll burn a hole. So I start back very far. Okay, so laser on.

So I start by- and I can see, there's the- argon blowing. So you see, as I zap it, it's blanching, it's not burning. You see how it's tightening. So that whole area now is completely flat, like it should be. Standby.

So I'm going to get the back part of the eardrum, which was a little less retracted, but still, nonetheless, it was retracted. Alright. Laser on.

Good. Alright, standby.

So that's pretty much it. So now we have a- an adequately tightened- eardrum. And that little bit of char there, that did not perforate it, but that's about where I'm going to put my tube. So now I'm going to put a T-tube in. We're done with the laser, so I'll take that.

So I'm just going to trim this.

CHAPTER 4

I'll take an alligator and a scissors. These T-tubes come out very long, longer than they need to be. So I'll trim off- a bit of each flange. Fold it back. So like that. Now hold it like that. And I'll take a myringotomy. I'll take a myringotomy blade.

Alright, I'll take a small suction. I don't think there's an effusion. Can you put a- like a 20 suction on?

And it's pretty dry in there. Now there's a nicely aerated middle ear space.

CHAPTER 5

Alright, so now… There we go. And I'll take full suction.

And so now, having this tube in there will help keep it aerated and keep the eardrum from retracting again.

Alright. That's it!