Hello, my name is Dr. John Lee. I'm the Oculoplastic and Reconstructive Surgeon for Boston Vision. I want to introduce a video of a surgery we're about to perform, it is a lateral tarsal strip procedure, and in this case, it's for an entropic lower eyelid. The surgery is first performed by anesthetizing the lateral canthal angle. This is done with 2% lidocaine and epinephrine on a very thin, 32-gauge needle. The initial step is to create a lateral canthotomy with Westcott scissors, and this is reflected inferiorly to complete an inferior cantholysis. Once the lower lid is fully mobile, it is draped laterally to approximate its new position. This position is marked on the lower eyelid margin. That portion of the lower eyelid is then separated from the anterior and posterior lamella, using Westcott scissors. The posterior tarsal strip is then prepared by deepithelializing it with the scissors and a 15 blade. Next, a 4-0 Mersilene suture, which is a non-absorbable suture, is used to reattach the tarsal strip to the periosteum of the lateral orbital rim. Once that's secured, the lateral canthal angle and skin are closed with a 6-0 plain gut suture in a running fashion.
So, do a little testing to see if he's numb. He suffers from an involutional entropion, where his lower eyelid rolls inward on him, causing persistent irritation, so we're gonna do a procedure called a lateral tarsal strip. We've already injected some lidocaine with epinephrine through the lateral canthus, all the way down to the lateral orbital rim, across the anterior and posterior part of the lateral lower lid, and the upper portion of the lateral canthal angle there. Just ensuring that he's numb. Excellent.
First step is we're gonna free the lower lid, make it more mobile. We'll start with the lateral canthotomy, so a pair of Westcott scissors incising through the lateral canthal angle, through the lateral canthal tendon. And I'm aiming for that lateral orbital rim. I can feel it just underneath that pair of scissors there. So that's the lateral canthotomy.
And we're gonna proceed with the inferior cantholysis. So if I pass my scissors here, it strums tight like a guitar string, and that's the lateral - sorry, the inferior crest of the lateral canthal tendon. So we're gonna incise through there. And you can see that the lower lid is freeing up. And now we have a very mobile lower lid.
So if we look where the upper lid ends, laterally - this is where the lower lid initially ended. We are gonna change that position, and make that there. So, mark it.
And then I'm gonna separate the posterior and the anterior lamella of the lower lid. On the forceps side will be the skin and orbicularis. On the globe side will just be the tarsus and the palpebral conjunctiva. I'm gonna go all the way to my previous mark. I'm gonna remove this strip that contains the follicles. And that gives me a freely mobile tarsal strip here.
The epithelium is still on the margin, so that's gonna be removed with the scissors. And there's still epithelium on the posterior surface of that tarsal strip, so that will be scraped off. And this is more strip than we need, so we will remove the excess portion. Can you load the Mersilene for me?
So our suture for this portion is a 4-0 Mersilene double-armed suture. It is a non-absorbable suture, so it will remain there. So what I do is I take my tarsal strip - I'm gonna pass the suture through the superior portion of it. And then I take the second half of that double-armed suture, grab the strip again, and pass it through the inferior portion of it. Now these two arms of the same suture will now recreate that lateral canthal tendon when we attach it to the orbital rim. So I can palpate down to the lateral orbital rim here, and I'm gonna pass that suture right through the periosteum of that orbital bone. So as I pass it, I can feel that I have a good purchase. A very solid connection. I take the second arm of the Mersilene suture, and I'm gonna aim a little more superiorly than the first pass. Again, I can feel the bone right underneath the suture. I'm grabbing periosteum. And this will function as a new lateral canthal tendon, and you can see how the lower lid is much more taut. So, scissors to you. Cut. Cut. And plain gut, please. Now before we secure these, we're gonna recreate the lateral canthal angle. We remove the lateral portion of the lower lid, so now this is gonna be the lateral aspect of the lower lid, and you still have the original lateral aspect of the upper lid, so these two parts are gonna be connected.
So this is a 6-0 plain gut suture. I'm just gonna grab a portion of what I want to be the new lateral canthal angle. And this is the original upper lid portion of the lateral canthal angle. And that should come together to form the new lateral canthal angle.
I'm gonna set aside this plain gut because I still have to secure the Mersilene sutures here. So typically I'll do a double-knot because this is under quite a bit of tension. And the knot will be buried just above the periosteum. Scissors to me. Dab. You can dab. Now all that remains is closure of the lateral canthotomy with the same 6-0 plain gut suture. That's gonna go from the newly created lateral canthal angle. And secure the suture to itself. The procedure is complete.