Navigation-guided Powered Endoscopic DCR

How do we go about doing navigation-guided powered endoscopic DCR in such complex cases? If you remember from the previous video, we were able to localize the sac quite high up and posterior. And that’s one of the reasons why I’m giving an incision a little superior to what the probe was showing.

And once I reflect this and cauterize it a bit, it’s all very soft tissue kind of a thing without any underlying clear bone at this point of time. So the probe was directed a little inferior to find the possible nasolacrimal duct and a lower half of the sac.

And there you can see I have opened it up now, and taking incision just like we do for a regular DCR. These are the S-shaped incisions just to reflect the flap a little bit. And this is the inferior incision using the crescent knife. Similarly, creating that interior sac flap. I’m trying to go a little higher as much as I can because the navigation was showing.

Now again, I’m using an interpretive navigation here. You can see that from this point, I need to go superiorly around 5 to 7 millimeters to find the lateral sac. Look at the position of the probe, which I exteriorized. So obviously, one should not be fooled by this probe and the navigation guidance.

I’m exposing a little bit of tissue so that I can expose the bone, underlying bone, and I can drill the bone. Now drilling this bone has to be done very carefully because there are no landmarks that you can really rely on. So it has to be done in a very controlled way, and very slowly, and making sure that with every step, you keep checking what is coming underneath. You can fairly rely because the stereotactic guidance was showing that the location is somewhere between 5 to 10 millimeters in this direction posterior and superior.

Now it’s also important that– one May argue the use of light pipes. They are fraught with a lot of issues. Here, you can see I’m using a Wormald’s suction cautery to cauterize. It’s not unusual in scarred areas to have this. And Wormald’s suction catery is very, very useful at this point. And once you achieve a decent cautery then you can continue with the exposure to the bone.

So I was saying that the use of light pipe can be very you know fraught with a lot of inconsistencies and wrong interpretations because of the scattering of the light in front of scarred tissues. And the location of the lacrimal sac here is quite different, so we can’t rely only on light pipe and go behind that. So we need accurate guidance here.

And there, you see I’m exposing the virgin lacrimal sac now– quite high placement if you can notice. So this is the posterior extent that I’m removing because the stereotactic guidance was saying it’s a little– you need to go a little more posterior.

Again, it needs to be done with a lot of thought and care. And there, you can see a very beautiful 8 to 10 millimeters off a nice virgin lacrimal-sac mucosa.

So I’m going to now expand that incision that I had taken infinitely, and join that superiorly in the same line. And there you see. You can see a nice, normal mucosa now, unlike the scarred one inferiorly. Taking S-shaped incisions, doing a 45 degrees optical test to make sure everything is OK, applying adjunctive like Mitomycin and intubation as routine.