BLOG: Making referrals for MIGS
Click Here to Manage Email Alerts
When I make a cataract surgery referral for a patient on an ocular hypertensive medication for glaucoma, my referral letter always states, “Cataract surgery with MIGS (minimally invasive glaucoma surgery).”
Fortunately, most of the cataract surgeons in my area are actively performing MIGS procedures. For mild to moderate disease, the most common procedure in our area is with the iStent inject W (Glaukos) trabecular micro-bypass stent. Those with moderate to severe glaucoma may get a Hydrus microstent (Ivantis), cycloablation or other more aggressive procedure.
It is so important to take advantage of the opportunity of cataract surgery to address glaucoma. Implantation of trabecular micro-bypass stents adds no risk to cataract surgery, nor does it alter the postoperative management in any way, except to lower IOP. MIGS can reduce IOP by about 7 mm Hg, compared to 5 mm Hg for cataract surgery alone (Samuelson, Sarkisian et al.). At 24 months, 75.8% of treatment eyes in this study, vs. 61.9% of control eyes, experienced at least a 20% reduction from baseline in unmedicated diurnal IOP (P = 0.005), and mean reduction in unmedicated diurnal IOP from baseline was greater in treatment eyes (7.0±4.0 mm Hg) than in control eyes (5.4±3.7 mm Hg; P < 0.001). MIGS at the time of cataract surgery can also reduce the burden of topical medications (Schweitzer et al.).
I always discuss MIGS with my glaucoma patients before cataract surgery, along with other aspects of surgery, like how long the procedure will take and what to expect from postoperative drops. I would encourage colleagues who are referring patients for cataract surgery to ensure that their surgical referral partners are performing MIGS so their patients can benefit from the procedure.
When the patient comes back to me, I wait until they are finished with postoperative steroids, typically at the 1-month visit. At that point, I will consider stopping one topical glaucoma medication and monitor the effect on IOP.
I also refer patients for MIGS even before they have glaucomatous damage if they have high IOP (greater than 30 mm Hg) without medication and poor compliance. We know from the Ocular Hypertension Treatment Study that these patients with high IOP are highly likely to convert to glaucoma (Gordon et al.), so the more we can do to prevent progression, the better.
For patients with more severe disease, MIGS procedures can be a bridge to delay or prevent trabeculectomy or tube shunt surgery.
Finally, it is important to remember that MIGS is not only for the poorly controlled glaucoma patient, and not only for those with cataract. I often refer patients to my glaucoma surgical colleagues when they are still well-controlled on topical medication but are struggling with the drops for some reason. That may be due to cost, dexterity or memory problems, or medication side effects such as ocular surface disease, which I discussed in my last post. Sometimes, the best treatment we can offer these patients is to find a solution that gets them off drops or reduces the number of drops they need.
References:
- Gordon MO, et al. Arch Ophthalmol. 2002;doi:10.1001/archopht.120.6.714.
- Samuelson TW, et al. Am J Ophthalmol. 2021;doi:10.1016/j.ajo.2021.03.007.
- Samuelson TW, et al. Ophthalmology. 2019;doi:10.1016/j.ophtha.2019.03.006.
- Schweitzer JA, et al. Ophthalmol Ther. 2020;doi:10.1007/s40123-020-00290-6.
For more information:
Nicole Albright, OD, is clinic director at Moses Eyecare Center in Merrillville, Ind., where she also serves as externship coordinator for optometry students from Indiana University and Chicago College of Optometry. She practices full-scope optometry, with a focus on specialty lenses, myopia management, perioperative care and ocular disease management.
Collapse