iPRIME Viscodelivery System: Increasing Precision and Visual Confirmation in Minimally Invasive Procedures
The iPRIME Viscodelivery System is a sterile, single-use, and minimally-invasive device developed to deliver viscoelastic fluid during surgical procedures. Recently, Arkadiy Yadgarov, MD; Paul Singh, MD; and Matthew Brink, MD, talked with Ophthalmology 360 about their early experience using the device, including its unique features and benefits and how it is fit into their practice.
Control and Flexibility: One of the advantages of iPRIME is having control and flexibility during the procedures, including the ability to independently advance the catheter and control the injection of viscoelastic, allowing the user to address different areas of resistance and adjust the amount of viscoelastic based on the patient’s needs.
Singh: What’s nice about the iPRIME device is it allows us to have independent control of advancing the catheter as well as independently dispensing viscoelastic. For some doctors who feel like they want more viscoelastic to expand the canal more, they have that control, or if you have a collapse of the canal or an area that is scarred down, you can actually inject some viscoelastic to balloon up the canal so you can get around it.
The iPRIME device also has 2 levers. One lever advances the catheter in the canal while the other slider allows us to pump viscoelastic into the canal, so there is independent control going forward or going on the way back. Its helpful to have the option to dispense viscolastactic on the way in or upon retraction.
Brink: I do a high volume of goniotomy and canaloplasty, and I have high expectations for good results. The iPRIME did not disappoint. In addition to achieving the goal of creating a clean goniotomy with very little if any bleeding, I found the extra control beneficial—especially for breaking through strictures in Schlemm’s canal. My results have been very comparable to other methods. iPRIME is a very compelling product because it gives me an extra level of control over how much viscoelastic I dispense as well as where and when I dispense it.
Visual Confirmation of Dilation: One of the benefits of the iPRIME device is the visual confirmation of dilation that occurs with use. The wide dilation of Schlemm’s canal can be observed instantly upon viscoelastic delivery, providing a visual confirmation of the effectiveness of the procedure.
Singh: We do know from intraoperative OCT studies that the more viscoelastic you inject, the more you see the canal dilate as well as stretch open the trabecular meshwork… we see the distal collector channels also dilating on intraoperative OCT. We don’t have great data yet to support this, but in my opinion, I do think that the volume of viscoelastic, in some cases, can make a difference in terms of efficacy, at least we see that visually in terms of how it expands the canal.
Yadgarov: The iPRIME does have the advantage of giving the surgeon the control of how much viscoelastic is delivered into the canal. Additionally, viscoelastic can be delivered at any time, not just upon retraction of catheter. The ability to deliver viscoelastic prior to catheter propagation is an advantage, since occasionally the surgeon may encounter strictures in Schlemm’s canal, making cannulation difficult. Being able to deliver viscoelastic prior to advancing the catheter provides a way to widen the strictures and facilitate easier advancement of the catheter within the canal. In addition, the blue catheter allows better direct visualization within the canal compared to the translucent iTRACK catheter.
I was amazed at how wide the Schlemm’s canal can dilate with viscoelastic delivery and that you can see this instantaneously upon delivery. This is due to a significant amount of viscoelastic that gets deposited upon sliding the actuator. Having visual confirmation of viscodilation of Schlemm’s canal is very satisfying and improves surgeon confidence in that an anatomic change has occurred.
Learning Curve: All the doctors agreed that the biggest learning curve when starting with the iPRIME device is utilizing the sliders because you are now using 2 fingers to do 2 different things while you’re in the canal.
Yadgarov: The iPRIME does have a steeper learning curve than some other MIGS, due to needing to control 2 separate sliding actuators on the device. I found myself to be comfortable and proficient after 8 to 10 cases.
Singh: Not only are you trying to maintain a good view and making sure that the catheters in the canal, but you’re also now having to use a second finger to pump viscoelastic on the way forward or the way back. You need muscle memory to allow yourself to feel comfortable and to get used to using a second finger. But it’s something that I think is very doable. And I think it’s something that the majority of surgeons who do procedures will feel comfortable doing that.
Brink: The device is intuitive and will be easy to pick up for surgeons who do angle-based procedures…The extra dimension added by the slider is something that becomes second nature. The rotating cannula tip is also helpful for dialing in the exact angle of approach.
Minimally Invasive Procedures: All doctors emphasize the importance of performing minimally invasive procedures. They discuss the benefits of procedures like canal dilation and viscodilation in terms of being less invasive and preserving healthy trabecular meshwork.
Singh: I’m a big fan of trying to be as minimally invasive to the target tissue as possible…In general canaloplasty and in general viscodilation procedures like this, I think it’s important to recognize that you have the ability to be as minimally invasive as you want or to be more aggressive if you need to combine viscodilation and the ability to perform a goniotomy or trabeculotomy. I think we are starting to realize that some patients don’t necessarily need a large amount of removal of trabecular meshwork; for some patients viscodilation and canaloplasty alone might be enough, especially in those earlier mild to moderate patients. This gives you the opportunity to treat earlier but not restrict you from other procedures down the road as well.
You don’t have to wait till cataract surgery to do a MIGS procedure, and I think these minimally invasive canal dilating procedures, like the iPRIME, give you the opportunity to intervene earlier and not burn your bridges for other procedures down the road.
