Retina co-morbidity for the anterior segment surgeon
Preventing and treating CME

Prophylaxis key in avoiding problems

Before (left half) and after (right half) treatment of CME with an NSAID

An epiretinal membrane, which makes it highly likely that the patient will have CME after routine cataract surgery Source: Uday Devgan, M.D.

Think of prophylaxis for cystoid macular edema (CME) like life insurance, said Keith A. Warren, M.D., president and CEO of Warren Retina Associates, Overland Park, Kan. Hopefully you won't need it, but it can give you some clinical peace of mind.
Uday Devgan M.D., chief of ophthalmology, Olive View–University of California, Los Angeles Medical Center, approaches CME with another analogy: "When CME occurs, it's like a carpet that's flooded. You can repair the carpet, but it's never quite the same," he said. That's why it's better to prevent CME after cataract surgery from occurring in the first place, Dr. Devgan said.
For these reasons, surgeons like Drs. Warren and Devgan take a full-on approach to prevent CME.
In addition to complications and poor visual outcomes, another reason to prevent it is because patients have trouble understanding how or why CME occurs, Dr. Devgan said.

Prophylaxis pointers

NSAIDs are the mainstay in prophylaxis for Dr. Devgan. He uses them a few days before and a few days after cataract surgery. Although this is actually an off-label use, he noted that it is a very common practice.
Dr. Warren uses both NSAIDs and steroids with tapering dosages to prevent CME. Surgeons like Dr. Devgan and Dr. Warren said that prophylaxis against CME is so common for them, it is hard to compare visual outcomes in eyes that have been treated prophylactically against eyes that have received no treatment, as just about all eyes they operate on receive the prophylaxis.
However, David D. Verdier, M.D., Verdier Eye Center, Grand Rapids, Mich., has a contrary view. "I do not routinely use NSAIDs following uncomplicated phaco," he said. "These drugs can incur significant expenses as well as induce corneal surface problems from toxicity and reduced sensation. … I do not know if prophylaxis in non-high-risk patients offers any advantage over prompt treatment of CME when it occurs in non-high-risk patients." That said, Dr. Verdier will use NSAIDs if the patient is at a higher risk for CME, with risk factors including epiretinal membrane, diabetes mellitus, cataract surgery complicated by vitreous loss, or a history of post-op macular edema after cataract surgery in the contralateral eye.
"In these settings, I routinely use an NSAID such as bromfenac [Bromday, Ista Pharmaceuticals, Irvine, Calif.], nepafenac [Nevanac, Alcon, Fort Worth, Texas], or ketorolac [Acular, Allergan, Irvine, Calif.]. I continue the NSAID until topical steroids have been discontinued," he said. Patients typically use these medications for 1-3 months, he said.
Dr. Verdier emphasized his preference for generic NSAID use. "Unless there is compelling evidence of an advantage of more expensive non-generics, I think generic NSAIDs might be considered, out of respect to our patients' financial health," he said.
He also believes that optimal dosing for NSAIDs, in his hands, differs from what manufacturers recommend. For example, he uses nepafenac twice a day instead of three times a day and ketorolac two times a day instead of four times a day.

Treating acute CME

When acute CME occurs post-operatively, Dr. Devgan checks to make sure that other anatomical defects, such as vitreous behind the lens, are not occurring. If he does not find anything, he uses topical NSAIDs for treatment and follows the patient with the use of ocular coherence tomography on a week-to-week basis. He usually finds some improvement within 1-2 weeks of the peak incidence, but treatment with medications will continue for several weeks. Dr. Devgan prescribes NSAIDs such as Bromday, Acular, and Nevanac, and sometimes genetic choices. He also uses a topical steroid such as prednisolone acetate 1% (Pred Forte, Allergan) or Durezol (difluprednate ophthalmic suspension 0.05%, Alcon) if NSAIDs do not seem to improve the eye. Dr. Verdier's treatment course for acute CME is very similar, adding that he will follow the treatment course and then taper over 1-3 months. "If [the patient] is recalcitrant to this treatment, I readily refer to a retinal specialist," he said.
Another CME treatment option is Diamox (acetazolamide, Duramed, Cincinnati), Dr. Devgan said. "Diamox as a pill lowers pressure in the skull and lowers IOP, and it may help with macular edema," Dr. Devgan said. Dr. Warren also treats CME with NSAIDs three times a day for 6 weeks and periocular steroids such as Durezol. He will administer a sub-Tenon's injection of triamcinolone 4 mg and discontinue the topical steroid but continue the NSAID for another 6 weeks if necessary.
"Generally at about 6 weeks, I see improvement," he said.
A push for effective topical treatment over injections is a crucial issue right now in CME, Dr. Warren said. "It's easier to do, and everyone likes it better," he said.

Treating chronic CME


Chronic CME, which can occur 3-6 months after surgery, can be challenging to treat if it's caused by an anatomical defect that was not fixed, Dr. Devgan said. "The longer CME is there, the worse the prognosis is," he said. "It's hard for the patient to understand what is happening." Certain patients have a greater risk for chronic CME, such as those with diabetic retinopathy, uveitis, or a history of CME in the other eye, Dr. Warren said. Dr. Warren reported in a 2010 study published in Retina a more aggressive treatment for chronic CME, involving intravitreal triamcinolone and an injection of bevacizumab (Avastin, Genentech, South San Francisco). The 39 patients in the study were randomized to receive one of four topical NSAIDs or a placebo for 4 months. At weeks 12 and 16, patients who received NSAIDs, particularly nepafenac and bromfenac, had a significant reduction in retinal thickness compared with those who received the placebo.

Editors' note: Dr. Devgan has financial interests with Alcon, Ista Pharmaceuticals, and Bausch + Lomb (Rochester, N.Y.). Dr. Warren has financial interests with Alcon, Dutch Ophthalmic Research Center (Zuidland, the Netherlands), and Genentech. Dr. Verdier has no financial interests related to this article.

Contact information

Devgan: 800-337-1969, devgan@gmail.com
Verdier: 616-949-2001, daverdier@aol.com
Warren: kwarren@warrenretina.com