Canaloplasty Glaucoma Surgery
Intended for eye surgeons/ glaucoma specialists who want to master canaloplasty. Canaloplasty is a minimally invasive glaucoma treatment. Although technically challenging, Canaloplasty has several advantages over traditional glaucoma treatments/ surgeries, specially in its safety profile.
Canaloplasty Glaucoma Surgery
Using Mastel Instruments: Part 3 – Catheterization
And now what I’m doing is I’m just going to place a little viscoelastic on, now, that deep flap, and see if I can also get that locked into place using the bridle suture. Now that’s going to keep from desiccating. Now I’ll just take the viscoelastic, and I’m just going to dilate the ostia of Schlemm’s canal here. And what that’s going to do is it’s just going to allow me to more easily cannulate with the iScience catheter. There are those who advocate that you actually place the tip of the viscoelastic cannula into Schlemm’s canal.
So on the right here, you have the standard Fechtner conjunctival forceps. And they have a large ring, which is used to atraumatically grasp conjunctiva. But what you see on the left is a Mastel prototype of an instrument which I think is just absolutely wonderful for canaloplasty, and you’ll see why in the next couple of minutes of this video.
This is a modification of the Fechtner forceps. And what’s been done is you now have two loops, side by side, and you’ll see just how wonderfully this can be used in canaloplasty for control.
So I really prefer to use this combination of the Mastel modification and the regular Fechtner’s for inserting the cannula. You’ll see here, the catheter with the tip. And what’s nice about this is that these side?by?side loops allow you to grasp the cannula in a way that just gives you full control.
And so you just rotate right here in parallel with the catheter, and it allows you to move the catheter into Schlemm’s canal with very little concern about kinking the catheter or crushing the catheter. You have a large surface area that’s grasping it. And it’s just a nice, natural motion.
You can see here that the catheter is moving through Schlemm’s canal. But right about this point, I hit an obstruction, and I can’t seem to get it through the obstruction. Now, generally, with a standard pair of forceps, I’m pushing, putting a fair amount of force on this. I would really risk kinking the catheter. But with this surface area, possible with the modified Fechtner’s, kinking just is no longer a real issue.
So I’m using the other Fechtner’s to try to press down and close off any collector channels that might be in the area. This just wasn’t going through. So I decide to go ahead and cannulate the other ostia. I’m just going to make sure I’ve got the best grasp of the catheter there, again, using all that surface area with these modified Fechtner conjunctival forceps. And now, just look at that, right past. So it’s amazing. Just because there’s an obstruction from one direction really does not mean that you’re going to have trouble going from the opposite direction. You saw how smoothly that went through.
Now the catheter is all the way through and around, and it’s time to tie the Prolene suture to the tip of the catheter. Now, this is another area where I just love the modification of the Fechtner’s. One of the most difficult things about this surgery is actually just getting this Prolene to behave. I use a 9-0 Prolene. I know others use 10-0 and take two lengths and suture through, but I prefer just using 9-0.
And look at this. This is what I do with this modification of the Fechtner. I place one loop on either side of the Prolene, and then I can just pull the Prolene right through there, essentially incarcerating it against the forceps and the sclera. So I can very, very quickly pull that Prolene through. I know, in the past, pulling the Prolene through, it would come away from the tip of the catheter. It could just be one of those frustrating things about using very fine sutures. So now that I’ve got the tip there, I’m just going to go ahead and tie the suture to the end of the tip.
About the Author: David Richardson, MD
Medical Director, San Marino Eye
David Richardson, M.D. is widely recognized as one of the top cataract and glaucoma surgeons in the US and is among an elite group of glaucoma surgeons in the country performing the highly specialized canaloplasty procedure. Morever, Dr. Richardson is one of only a few surgeons in the greater Los Angeles area that performs Micropulse® "Cyclophotocoagulation" (MP3) glaucoma laser surgery. Dr. Richardson graduated Magna Cum Laude from University of Southern California and earned his Medical Degree from Harvard Medical School. He completed his ophthalmology residency at the LAC+USC Medical Center/ Doheny Institute. Dr. David Richardson is also an Adjunct Assistant Professor of Clinical Ophthalmology at Keck School of Medicine of USC. Twice weekly, he treats veterans at the VA Greater Los Angeles Veterans Healthcare System.