Article

CLINICAL: Glaucoma

Making the Case for MIGS

Cataract surgery-plus options have merit as treatment options

A healthy, 72-year-old male with stable, early open-angle glaucoma complains of painless, progressive loss of vision OU for the last several months.

His IOPs are within the mid-high teens target range, an improvement from low 20 pre-treatment levels.

Additionally, the patient is well controlled with current topical prostaglandin analogue monotherapy OU.

His clinical exam also shows progressing cataracts, the culprits for his complaints, with otherwise normal, stable ocular health and testing.

The patient asks: “Will cataract surgery help my glaucoma?”

How should we approach this case, and how would you answer that question? In short, the answer is “yes,” and we should take this opportunity to refer the patient for a combined MIGS (minimally invasive glaucoma surgery) procedure too.

WHY MIGS?

Uncomplicated and planned solo cataract surgery alone has been shown to result in an average post-operative IOP reduction of 1.6 mmHg.1,2 With the growing presence of MIGS techniques and devices, the early/moderate cataract-glaucoma patient now has a unique opportunity to achieve even lower post-op IOP levels and, ideally, decreased dependence on topical drugs.

WHAT PROCEDURE SHOULD THE PATIENT UNDERGO FIRST?

If a patient had advanced (but stable) glaucoma and visually significant cataracts, which procedure would be best for him to undergo first?

In such a situation, it is best to do the cataract surgery first and then the trabeculectomy/filtration procedure if needed and then, ideally, only several months after cataract surgery. The reason: Studies show that performing the trabeculectomy surgery prior to cataract surgery, or too soon after cataract surgery, increases the risk of bleb failure.5

By planning ahead and taking advantage of these “cataract surgery-plus” options, such as canaloplasty procedures, trabecular meshwork removal procedures, trabecular meshwork bypass devices and subconjunctival devices, patients have achieved 20% to 40% post-op IOP reduction levels, depending on the procedure and the patient’s response to treatment.3,4

For additional coverage on MIGS, see:

THE O.D.’S ROLE

When it comes to the post-operative co-management of MIGS patients, optometrists should be mindful of relatively transient hyphemas and IOP spikes. (For additional information on these possible events, see bit.ly/2OC3V5m .) When caring for patients who have glaucoma, it is helpful to think long-term and, therefore, play the long-game. In the right patient, and with proper planning, cataract surgery (especially combined with MIGS) can be an effective way to help meet their current and long-term needs. OM

REFERENCES

  1. Matsumura M1, Mizoguchi T, Kuroda S, Terauchi H, Nagata M. Intraocular pressure decrease after phacoemulsification-aspiration+ intraocular lens implantation in primary open angle glaucoma eyes. Nihon Ganka Gakkai Zasshi. 1996; 100: 885–89.
  2. Yang HS, Lee J, Choi S. Ocular biometric parameters associated with intraocular pressure reduction after cataract surgery in normal eyes. Am J Ophthalmol. 2013; 156: 89–94.
  3. Kung JS1, Choi DY1, Cheema AS1, Singh K. Cataract surgery in the glaucoma patient. Middle East Afr J Ophthalmol. 2015 22:10–17.
  4. Pillunat LE, Erb C, Jünemann AG, Kimmich F. Micro-invasive glaucoma surgery (MIGS): a review of surgical procedures using stents. Clin Ophthalmol. 2017; 11: 1583–1600.
  5. Husain R, Liang S, Foster PJ, et al. Cataract surgery after trabeculectomy: The effect on trabeculectomy function. Arch Ophthalmol. 2012; 130: 165–70.