July 2017

 

COVER FEATURE

 

MIGS roundup
Laying the groundwork for CyPass use


by Vanessa Caceres EyeWorld Contributing Writer

   

CyPass shown in the eye
Source: Quang Nguyen, MD

Glaucoma surgeons familiar with the MIGS device share surgery and patient selection pearls

For cataract surgery in mild to moderate glaucoma patients, the CyPass Micro-Stent (Alcon, Fort Worth, Texas) now offers another treatment option. The CyPass was approved in the U.S. last summer by the U.S. Food and Drug Administration.
The device was approved specifically for mild to moderate glaucoma, and that’s a description that surgeons familiar with CyPass support as well. “It’s for patients with open angles who have an IOP in the 20s [and who are] on one or two medications,” said E. Randy Craven, MD, Wilmer Eye Institute, Johns Hopkins University, Baltimore.
“Since you’re taking the cataract out at the time of the procedure, the person’s angles will be open, so there’s no worry about narrow angles,” said Brian Flowers, MD, Fort Worth, Texas. “I do find that it works even in patients on multiple medications.”
Patients who would not do as well with the CyPass are those with an uncontrolled high IOP who are on multiple medications and those with inflammatory or neovascular glaucoma. “I would avoid doing the CyPass in ‘train wreck’ scenarios. Keep it to people controlled on medications first,” recommended Steven Sarkisian, MD, clinical professor and glaucoma fellowship director, Dean McGee Eye Institute, University of Oklahoma, Oklahoma City. He added that the micro-stent has not yet been tested in pediatric glaucoma. A nanophthalmic patient would also give Dr. Flowers some pause.

Surgical pearls

There are a few ways you can better manage CyPass implantation, according to surgeons who are familiar with the device through its clinical trials.
“You have to be comfortable with intraoperative gonioscopy and have a clear view of the angle anatomy and know the surgical landmark of the angle,” said Quang Nguyen, MD, associate head, Division of Ophthalmology, and director of the glaucoma service, Scripps Clinic, La Jolla, California.
“When inserting, the height of the elbow seems to predicate the angle of approach. You need the tip to ‘glide’ along the sclera. It’s better to underinsert and then tap into place. If it hangs up, stop,” Dr. Craven advised. “The angle of insertion needs to be adjusted. This is usually where you want the elbow up.”
“Avoiding 3 and 9 o’clock is also helpful because the ciliary plexus is there, and the patient may feel the implant as it goes in if under topical anesthesia,” Dr. Sarkisian said.
Dr. Flowers advocates tilting the patient’s head less than you do for angle surgery. “People doing angle surgery are used to rotating the head by 45 degrees. But with this, since you’re trying to implant perpendicular to the iris, you don’t want the head rotated as much—probably 10 to 15 degrees less,” he said.
He also recommends implanting the device slightly deeper versus superficially. “You could get some corneal changes with superficial implantation,” Dr. Flowers said.

Planning on IOP reduction, avoiding complications

The CyPass is able to offer greater IOP reduction than phacoemulsification alone, Dr. Nguyen said. “The COMPASS trial revealed unequivocal scientific data that demonstrates the additive effect of CyPass to phaco surgery to provide excellent control long term,” he said.
“You can expect a 20% to 40% drop in IOP, depending on the preoperative IOP and number of meds,” Dr. Sarkisian said. “This has been proven to be superior to phaco alone in the U.S. pivotal trial and as effective as a standalone procedure in patients outside the U.S.”
Although there is still nothing as effective as trabeculectomy at lowering IOP, Dr. Sarkisian said, complications from trabeculectomy prompt him to avoid it unless all other options have failed.
One other factor tracked by surgeons is reduction in medication use. In the COMPASS trial, mean medication use decreased from 1.4 to 0.2 in the micro-stent group compared with 1.3 to 0.7 in the group having cataract surgery alone.1 “Mean 24-month medication use was 67% lower in microstent subjects (P<0.001); 59% of control versus 85% of microstent subjects were medication free,” according to investigators.
The complications associated with CyPass are self-limiting with no long-term effects, Dr. Nguyen said. One complication that he has seen is a larger-than-expected cleft, due to surgeon error from not entering straight at the time of implantation.
“Although I have yet to experience it, one can postulate that if you make lateral movements, you can cause a cleft,” Dr. Sarkisian agreed. “The CyPass has an intuitive implantation technique, but it is not easy, and you have to be trained properly to implant the device.”
Another possible complication is a higher IOP right after insertion, Dr. Craven said. “This happens in patients with more significant glaucoma. It usually gets better with patient observation. Use aqueous suppressants and steroids and wait,” he advised.
Bleeding and a low IOP are possible but are fairly uncommon, Dr. Flowers added.

Options for cataract surgeons

Cataract surgeons should be prepared to have a microinvasive glaucoma surgery (MIGS) approach they can use, said the surgeons interviewed by EyeWorld.
“You can’t afford to not have a MIGS procedure in your armamentarium,” Dr. Sarkisian said. “The learning curve for the CyPass is reasonably short, and once a surgeon has gotten over that, the opportunity to use the CyPass will avail itself frequently.”
One other advantage that Dr. Nguyen sees is the opportunity to intervene earlier in the course of glaucoma and offer better IOP control, with the possibility of reducing glaucoma medications.
“From a technical standpoint, it’s doable. If you can do phaco, which is a relatively complex skill to learn, you could certainly learn this,” Dr. Flowers said. The device also now has an improved inserter, which makes CyPass implantation more seamless, he added.
“General ophthalmologists are afraid of extremely low pressures, but I haven’t had that with the new inserter,” Dr. Flowers said.
One area getting mixed results is reimbursement. Some surgeons have had no problems, while others are still struggling. Dr. Sarkisian’s billing team has received help from those at Alcon to achieve reimbursement for use of the device.

Reference

1. Vold S, et al. Two-year COMPASS trial results: Supraciliary microstenting with phacoemulsification in patients with open-angle glaucoma and cataracts. Ophthalmology. 2016;123:2103–12.

Editors’ note: Dr. Craven and Dr. Sarkisian have financial interests with Alcon. Dr. Flowers and Dr. Nguyen have no financial interests related to their comments.

Contact information

Craven
: ercraven@yahoo.com
Flowers: bflowers@oafw2020.com
Nguyen: nguyen.quang@scrippshealth.org
Sarkisian: steven-sarkisian@dmei.org

Laying the groundwork for CyPass use Laying the groundwork for CyPass use
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