cme
Bevacizumab for Preventing
CME
After Cataract Surgery
One surgeon is using the drug off-label with
promising results for patients with retinal disease.
Corticosteroids and NSAIDs have traditionally been used to prevent and treat cystoid macula edema (CME) following cataract surgery. However, James P. Gills, M.D., clinical professor of ophthalmology at the University of South Florida and founder and director of St. Luke's Cataract and Laser Institute in Tarpon Springs, Fla., has recently suggested that bevacizumab (Avastin, Genentech) may be a better alternative for patients who have retinal disease. Dr. Gills advocates intraocular drugs for surgery for several reasons, including increased compliance, convenience, lower cost, comfort and better control of the dose and placement of the drug. He has been using intraoperative intravitreal triamcinolone acetonide (Kenalog, Bristol Myers-Squibb) routinely to prevent CME in most of his patients along with a postoperative regimen of topical steroids and/or NSAIDs, and he has seen a 3% drop in the incidence of CME as compared to topical steroids and NSAIDs alone.
Ophthalmology Management recently spoke with Dr. Gills during a phone interview to learn more about how he is using bevacizumab for his patients undergoing cataract surgery.
OM: How many patients have CME after cataract surgery?
Dr. Gills: It really depends on what technology is being used. Fewer than 5% of patients have clinical CME that can be seen with fluoroscein angiography. However, if you perform photostress tests and OCTs on all your patients, you'll find that about 20% of them have what could be classified as clinical CME, and that is not picked up by routine exam.
This is why we believe in doing OCTs on all our patients preoperatively if they have any retinal disease and OCTs on postop patients if they have any evidence of CME, even if their vision is 20/20 and they complain of a little blur.
OM: What is the role of vascular endothelial growth factor (VEGF) in cataract surgery?
Dr. Gills: There are VEGF receptors on the cell plasma membrane that upregulate the activity of VEGF when there is increased activity in the eye, such as with cataract surgery. This upregulation causes an increase in inflammation. While there is increased tendency for inflammation in patients who have vasoproliferative disease, this reaction to injury occurs in all patients. However, while you want a certain amount of reaction to promote wound healing, too much VEGF production has an adverse effect.
OM: What are the effects of Avastin on patients who have cataract surgery?
Dr. Gills: We have performed several cases where we pretreated cataract patients 1 week prior to surgery with intraocular Avastin and patients have not required any other medications after surgery to prevent CME.
We do this before surgery because, if we give Avastin at the time of surgery, we get an increase in inflammation in some cases. It can be used either with Kenalog or alone.
OM: For whom are you using these preoperative injections?
Dr. Gills: We are currently using Avastin for patients who are diabetic. We do not use Avastin for patients who are not predisposed to retinal pathology, but we might consider injections for patients who cannot or do not want to use topical drops. However, it would be rare to consider it for patients without a pathological condition within the eye.
OM: What is your preoperative regimen?
Dr. Gills: First we do an OCT. We analyze the retinal condition and, if we feel the patient is at risk for advancing neovascular proliferative disease, we give one or more of a series of injections to quiet the retina. After the retina is quiet, we then consider doing cataract surgery.
OM: Do you use Avastin postoperatively?
Dr. Gills: Injecting Avastin after cataract surgery for conditions such as CME or other retinal neovascular problems, such as diabetic retinopathy, is common. The question is, should it be done along with Kenalog or instead of Kenalog? Should it be the routine procedure after cataract surgery for CME that is decreasing vision?
I had one case where the patient had 20/60 vision. At 1-month postop, the patient had CME that had been present for 1 week. We injected about 2 mg of Avastin and in 24 hours, the vision had improved from 20/60 to 20/20. What is important about this is had we put them on Kenalog it would have been about 1 week. If we had put them on drops, it would have probably been about 3 weeks. Is Avastin not the best medicine to use in patients with CME following cataract surgery?
OM: What is your postop regimen?
Dr. Gills: We usually use very little in the way of drops after surgery. Our typical protocol is a steroid three times a day, and an NSAID twice a day. Generally, I feel NSAIDs are particularly indicated in high-risk patients. If vision is significantly less than anticipated postoperatively, we will also inject Avastin.
OM: Are Avastin injections safe for cataract patients?
Dr. Gills: The only problem we have encountered are minor vitreous hemorrhages. We have had no retinal detachments or endophthalmitis in over 1,000 injections. The beauty in this is that we do not have the pressure rises that we did with Kenalog. We did have some keratitis when we increased the use of povidone-iodine. Povidone-iodine has a pH of 4 rather than a pH of 7 or 7.4, which can cause hypotony and subsequent endothelial keratitis.
We know that you cannot use Avastin at the time of surgery we think it is unwise because we have observed that Avastin may cause increased inflammation at the time of cataract surgery. The inflammation seen when Avastin is given at the time of cataract surgery may be due to the competitive action of the anti-VEGF and inflammatory agents on the VEGF receptor sites of the cell wall. We believe this may be the cause of increased inflammation.
OM: Do you anticipate widespread adoption of this type of prophylaxis for CME in cataract surgery?
Dr. Gills: I think Avastin is going to be one of the big things that we are going to be able to use in many different ways in the eye and throughout the body. It is one of the more interesting medicines that we have, but I think we're going to have to keep our minds open as to how it will be used.