Minimally invasive techniques, advanced technologies enhance safety of cataract surgery in diabetic patients

Cataracts develop more frequently and at an earlier age in patients with diabetes, according to clinical and epidemiological studies. With the rapid increase of both type 1 and type 2 diabetes worldwide, the number of cataract surgeries in diabetic patients is steadily on the rise.

Minimally traumatic microincision cataract surgery with the latest IOL technology has become a safe procedure in eyes with a high potential for inflammatory reaction, such as those of diabetic patients.

To start, all diabetic patients who undergo cataract surgery must have a complete examination that specifically looks for neovascularization of the iris and the degree of diabetic retinopathy, according to David S. Boyer, MD.

“If the diabetes is long-standing, a retinal consult or widefield fluorescein angiography may reveal subtle neovascularization elsewhere or severe non-perfusion,” he said. “Severe non-perfusion puts the patient at greater risk for the development of neovascularization of the iris. An OCT is helpful to determine if there is any subtle macular edema and to establish a baseline for retinal thickness.”

Image: Moshfeghi AA

According to Susanne Binder, MD, OSN Europe Edition Board Member, a surgeon does not have much to worry about if a few simple rules are followed.

“My first thought is to look for retinal changes, and then I take into account the higher risk of infection and the longer time for healing,” she said. “If there are no retinal changes, I treat diabetic patients as normal cataract surgery patients. In case of background retinopathy which does not necessitate laser treatment, I just follow the patient more closely after surgery to see how the retinopathy evolves.”

In cases of proliferative diabetic retinopathy, cataract surgery should be postponed and the pre-existing condition treated with laser. Anti-VEGF or corticosteroid injections are used, depending on the surgeon’s preference, in cases of diabetic macular edema.

When a patient develops a significant cataract, Andrew A. Moshfeghi, MD, MBA, OSN Retina/Vitreous Board Member, reminds the cataract surgeon and patient that DME treatment does not have to be finished in order to proceed with cataract surgery.

“I simply like to have good control of the DME prior to initiating the cataract surgery and then to coordinate with the cataract surgeon so that the cataract surgery takes place 1 to 2 weeks after the most recent anti-VEGF injection ipsilaterally,” he said. “That way, the patient’s macula is exposed to the highest concentrations of anti-VEGF agent at the time of the cataract surgery to blunt any pro-inflammatory effect the cataract surgery may have on their DME.”

Having a clear picture of the retinal conditions is mandatory because operating on a patient with advanced retinal complications “is like uncorking a champagne bottle,” according to Francesco Bandello, MD, FEBO.

“The retinopathy runs wild and progresses rapidly in a way you cannot always control,” he said.

Fortunately, cataracts nowadays are rarely so dense at presentation that they do not allow a good view of the ocular fundus or an OCT scan.

“If there is a risk that the retinopathy might get worse, I inject an anti-VEGF at the time of surgery. This will protect the eye for at least 1 month. I also apply a suture to the wound, in case laser is needed later on. I more rarely use steroids because I take into account that an infection might occur, and steroids would depress the immune defenses,” he said.

In the rare cases in which the cataract is too dense to allow preoperative OCT, Binder uses intraoperative OCT to examine the retina immediately after lens removal. If there is edema, she promptly administers steroids or an anti-VEGF.

“If you don’t have an intraoperative OCT, you have to see the patient very soon after the surgery, do your OCT examination, and if you see some edema, you must treat it quickly with corticosteroids or anti-VEGF,” she said.

Minimally traumatic surgery and IOLs

Surgeons do not need to change their routine cataract procedure when dealing with a diabetic patient, according to Ehud Assia, MD, OSN Europe Edition Board Member.

“The only thing I do is provide the patients with NSAIDs, particularly nepafenac, if there is some activity. If the retina is quiet, well-controlled, it is not needed. I use the same parameters as for routine surgery and don’t change my surgical technique,” he said.

Binder routinely performs surgery with intraoperative OCT and looks at the fovea at the end of surgery.

“In a normal healthy patient, foveal thickness increases after cataract surgery by no more than 8 µm. This increase is transient and subclinical. In diabetic patients, the swelling tends to be greater, but we have no data yet to prove that this is the rule,” she said.

In diabetics, non-silicone IOLs should always be considered. According to Brian T. Kim, MD, uncontrolled diabetics or younger diabetics with visually significant cataracts are more likely to develop advanced retinopathy in their lifetime and may be at a higher risk for needing vitrectomy in the future.

“It is for this reason I try to avoid the scenario of having a silicone IOL in a patient with advanced retinopathy whenever possible,” he said. “I prefer using acrylic lenses in diabetic patients who have or are at risk for developing severe retinopathy. I also prefer IOLs with larger optics to maximize retinal visualization.”

Moshfeghi agreed that the use of silicone lenses may create challenges for patients who require vitreoretinal surgery.

“Silicone IOLs can become foggy intraoperatively during fluid-air exchange and create unnecessary challenges for the vitreoretinal surgeon,” he said. “Additionally, if I’m planning to use silicone oil, oil droplets can persist on a silicone-based IOL even after silicone oil removal. These can be visually significant enough to justify later removal of a silicone IOL.”

Should the patient need vitrectomy due to vitreous hemorrhage, the contact with silicone oil would produce changes to the lens.

“In the past, intraocular lens implantation was considered to produce inflammation, and we feared to implant it in a diabetic patient because of the stronger reaction and maybe vessel growth on the lens. Now we know it is not true. Aggressive diabetic retinopathy may produce vessel growth everywhere, on the iris and retina and on any given scaffold, but this has nothing to do with the lens itself,” Binder said.

“With the currently available IOLs, it makes no difference whether the patient has diabetes or not,” Bandello said.

Both hydrophilic and hydrophobic acrylic lenses work well, according to Assia.

“Silicone lenses are better avoided, and anyway there are very few silicone lenses on the market now. Acrylics do very well,” he said.

As far as premium IOLs are concerned, toric lenses are a possible option.

“I use toric but not multifocal lenses. Although there is no absolute contraindication, I would not recommend these lenses to diabetic patients,” Assia said.

Multifocal lenses are not advisable due to possible macular changes that can limit their action, Pavel Rozsíval, MD, OSN Europe Edition Board Member, said.

“Their implantation has to be very carefully weighed and discussed with patients who are asking for them,” he said.

Postoperative course requires vigilance

According to Rozsíval, diabetic patients should be treated as standard cataract patients in the postoperative period, with attention to possibly more irritation and reaction in the eye, checking and treating them more frequently if needed.

The classic combination of steroids, NSAIDs and antibiotics for 3 to 4 weeks is normally used, but NSAIDs can be used for longer periods, from 5 weeks to 2 months, particularly if there are signs of inflammation.

Posterior capsule opacification does not occur more frequently than in non-diabetic patients.

The follow-up schedule is basically the same as in non-diabetic patients, but if there are signs of inflammation, or if the patient reports pain and vision loss, closer follow-up visits are needed.

“Generally speaking, if previous retinal lesions are treated well before surgery, there is little chance of reactivation. Different is the case of a patient with active lesions that are likely to be worsened by cataract surgery. In such cases, a close follow-up is necessary,” Bandello said.

A multicenter study conducted by the DRCR.net in a group of 293 patients showed that eyes with a history of DME treatment and/or DME immediately before cataract surgery are at higher risk for developing macular edema. The study authors recommended that “clinicians should continue to maintain vigilance in diabetic patients after cataract extraction even when central ME is not present immediately prior to cataract surgery.”

In case of macular edema developing postoperatively, anti-VEGF injections are currently recommended as first-line treatment. However, Binder believes that corticosteroids better comply with the multifactorial origin of DME than anti-VEGFs, which are targeted against only one factor. Anti-VEGFs have the advantage of fewer side effects, but they might cause fibrosis of the vitreous.

“If the patient has already some tractive vitreous changes, the use of anti-VEGF could be dangerous,” she said.

Bandello agreed that corticosteroids are ideal to control the inflammatory component and the cascade of events leading to edema and severe retinal complications in diabetic patients.

“Particularly in the form of intravitreal implants, steroids provide long-lasting protection and are particularly effective in cases of chronic DME. Not at the time of surgery, but some time before or after cataract surgery, steroids are a viable option. In recent-onset DME, anti-VEGFs should be preferred,” he said.

Kim agreed that corticosteroids are effective in treating DME; however, he tries to avoid using them as first-line treatment due to the risk of IOP elevation and the potential for accelerating cataract formation, particularly if DME is unilateral or if a mild cataract is present with relatively good visual acuity.

“Particularly in consideration of recent study data and FDA medication approvals, I typically initiate treatment of DME with anti-VEGF regardless of lens status,” he said. “Not only are we seeing a reduction of macular fluid, we are also seeing an additional benefit of these medications on improving the overall severity of retinopathy.”

If there is persistent macular edema despite anti-VEGF therapy, Kim suggested supplementing anti-VEGF treatments with steroids.

“I typically start with 2 mg of triamcinolone to evaluate for steroid response and increase to 4 mg if it is well-tolerated,” he said. “In general, however, I titrate the need for steroids on an individual basis. If frequent steroid injections are required, previous vitrectomy has been performed or compliance is an issue, I certainly consider using extended-release implants like Ozurdex (dexamethasone intravitreal implant, Allergan) or Iluvien (fluocinolone acetonide intravitreal implant, Alimera Sciences).”

Cooperation and interdisciplinary approach

For the cataract surgeon operating on a diabetic patient, cooperation with a vitreoretinal specialist might be necessary in some instances.

“The advanced care of some patients with coexisting retinal disease and cataract depends upon great interaction or great information flow between retina specialists and cataract surgeons,” John A. Hovanesian, MD, FACS, OSN Cataract Surgery Section Editor, said.

He suggested that many cases would benefit from consulting with retina specialists before cataract surgery, particularly in cases that are suspicious for further problems.

“Some patients with proliferative diabetic disease need retinal photocoagulation,” he said. “Patients with macular edema need it treated usually with injections of anti-VEGF or steroids. And most often we want to de-risk the surgery by addressing the diabetic disease first to the extent we can.”

“Not in routine cases, but in cases with diabetic retinopathy, and especially with macular edema, cooperation is vital. Not to speak of patients with proliferative changes or vitreous hemorrhage, where cooperation is mandatory,” Rozsíval said.

“Most complications of cataract surgery in a diabetic patient are retinal; therefore, an interdisciplinary approach is necessary,” Assia said. “Cataract surgery is an acute event. DR is a chronic event. The cataract surgeon can deal very well with preoperative evaluation, surgery and short-term follow-up, and then the patient should be in the hands of the retina specialist again. I don’t need a retina specialist during surgery, but I do during the follow-up.”

Binder said that cataract surgery has become so minimally traumatic that vitreoretinal complications are unlikely to occur intraoperatively.

“Whether you are an anterior or a posterior segment specialist, there is no great difference in the approach to surgery. As a vitreoretinal specialist, I might take a little more time to talk to the patient about problems that might occur, but from a technical point of view, our skills are comparable,” she said.

On the other hand, cataract surgeons often have to deal with high patient volumes and tight schedules for surgery.

“They may not have enough time for a detailed retinal evaluation preoperatively. Also, cataract surgeons are used to such good outcomes that they might be relatively less vigilant than us in the postop,” Bandello said.

According to Rozsíval, diabetes is not the only condition in which posterior segment status has to be taken into account in view of cataract surgery and vice versa.

“Our national vitreoretinal society has a motto: ‘There’s more behind the lens than meets the eye,’” he said. “European surgeons are usually trained to deal with both the anterior and posterior segment of the eye, but cooperation remains essential and should include also the patient’s GP and diabetologist.”

In addition to utilizing the expertise of both the cataract surgeon and retina specialist, Kim said it is important for a patient with diabetic retinopathy to understand the visual prognosis before undergoing cataract surgery.

“Every diabetic patient with preoperative retinopathy or macular edema should be considered for evaluation by a retina specialist,” he said. “In all cataract patients with diabetic manifestations, I think it is important that the patient understand the potential for having limited visual improvement and/or a prolonged healing time with cataract surgery.” – by Michela Cimberleand Kristie L. Kahl

• References:
• Boyer DS, et al. Ophthalmology. 2014;doi:10.1016/j.ophtha.2014.04.024.
• Ciulla TA, et al. Expert Opin Pharmacother. 2014;doi:10.1517/14656566.2014.896899.
• Cunha-Vaz J, et al. Ophthalmology. 2014;doi:10.1016/j.ophtha.2014.04.019.
• Diabetic Retinopathy Clinical Research Network, et al. N Engl J Med. 2015;doi:10.1056/NEJMoa1414264.
• Diabetic Retinopathy Clinical Research Network Authors/Writing Committee, et al. JAMA Ophthalmol. 2013;doi:10.1001/jamaophthalmol.2013.2313.
• Diabetic Retinopathy Clinical Research Network Authors/Writing Committee, et al. JAMA Ophthalmol. 2014;doi:10.1001/jamaophthalmol.2013.6209.
• Garcia-Martin E, et al. Invest Ophthalmol Vis Sci. 2013;doi:10.1167/iovs.13-12390.
• Haritoglou C, et al. Clin Ophthalmol. 2013;doi:10.2147/OPTH.S34057.
• Li L, et al. BMC Ophthalmol. 2014;doi:10.1186/1471-2415-14-94.
• Pollreisz A, et al. J Ophthalmol. 2010;doi:10.1155/2010/608751.
• Praveen MR, et al. Eye (Lond). 2014;doi:10.1038/eye.2014.60.
• Sayin N, et al. World J Diabetes. 2015;doi:10.4239/wjd.v6.i1.92.

• For more information:
• Ehud Assia, MD, can be reached at Ein Tal Eye Center, 17 Brandeis St., Tel Aviv 62001 Israel; email: assia@netvision.net.il.
• Francesco Bandello, MD, FEBO, can be reached at Scientific Institute San Raffaele, Milano, Italy; email: bandello.francesco@hsr.it.
• Susanne Binder, MD, can be reached at Rudolph Foundation Clinic, Juchgasse 25, 1030 Vienna, Austria; email: susanne.binder@wienkav.at.
• David S. Boyer, MD, can be reached at Retina Vitreous Associates Medical Group, 8641 Wilshire Blvd., Suite 210, Beverly Hills, CA 90211; email: vitdoc@aol.com.
• John A. Hovanesian, MD, FACS, can be reached at Harvard Eye Associates, 24401 Calle De La Louisa, Suite 300, Laguna Hills, CA 92653; email: drhovanesian@harvardeye.com.
• Brian T. Kim, MD, can be reached at Harvard Eye Associates, 24401 Calle De La Louisa, Suite 300, Laguna Hills, CA 92653; email: briankim@harvardeye.com.
• Andrew A. Moshfeghi, MD, MBA, can be reached at Keck School of Medicine, University of Southern California, 1450 San Pablo St., Suite 4700, Los Angeles, CA 90033; email: andrew.moshfeghi@usc.edu.
• Pavel Rozsíval, MD, can be reached at Charles University, Ophthalmology Department, Sokolská 581, 50005 Hradec Králové, Czech Republic; email: rozsival@lfhk.cuni.cz.

Disclosures: Assia reports he is a consultant to Hanita Lenses. Bandello reports he is a consultant to Alcon, Allergan, Bausch + Lomb, Genentech, Novartis, Sanofi Aventis, Farmila-Théa, Bayer, Hoffmann La Roche, Alimera Sciences, Novagali Pharma and ThromboGenics. Binder reports she is a consultant to Carl Zeiss Meditec. Boyer reports he is a consultant to Regeneron, Roche, Bayer, Genentech, Allergan and Optovue. Hovanesian reports no relevant financial disclosures. Kim reports no relevant financial disclosures. Moshfeghi reports he is a consultant for Genentech and Alimera. Rozsíval reports he receives a honorarium from Alcon and Zeiss for lectures.

What are the criteria guiding your choice between anti-VEGFs vs. steroids in pseudophakic patients with DME?

Anti-VEGF injections have better ocular safety profile than steroids

A subanalysis of Protocol I from the Diabetic Retinopathy Clinical Research Network, “Randomized trial evaluating ranibizumab plus prompt or deferred laser or triamcinolone plus prompt laser for diabetic macular edema (DME),” demonstrated that visual acuity improvement in the triamcinolone plus prompt laser group appeared comparable to that in the Lucentis (ranibizumab, Genentech) groups in the subset of pseudophakic eyes at baseline. However, among the subgroup of 62 pseudophakic eyes at baseline in the triamcinolone plus prompt laser group, 30 (48%) had one or more of the ocular hypertension events, compared with 10 (10%) and 15 (14%) among the 101 and 110 pseudophakic eyes at baseline in the sham plus prompt laser and ranibizumab groups, respectively.

Therefore, my first-line treatment for center-involved DME is an anti-VEGF agent even in pseudophakic eyes, in order to minimize the side effect of ocular hypertension. I would consider intravitreal steroids in a pseudophakic patient with DME if the patient does not have a history of steroid-responsive IOP elevation and is refractory to anti-VEGF agents. I may consider using steroids earlier if the patient cannot return frequently for the number of anti-VEGF injections and follow-ups needed during the first year of treatment or has any condition that poses a risk for the patient by receiving an anti-VEGF agent, such as during pregnancy or having had a recent cerebrovascular or cardiovascular event.

Judy E. Kim, MD, is an OSN Retina/Vitreous Board Member and professor of ophthalmology at the Medical College of Wisconsin. Disclosure: Kim reports she is on the advisory board for Alimera Sciences, Allergan, Genentech and Novartis.

Steroid implants can be confidently used in many cases

I consider steroids as an excellent option in a number of cases, first of all in the group of patients who do not respond to anti-VEGF therapy. Personally, I do not think we need six injections to classify the patient as a non-responder. If no changes are seen with three injections, I switch to steroids, particularly, but not only, in pseudophakic patients. My first choice is Ozurdex (dexamethasone, Allergan) because it does not have significant side effects, and if there is an IOP increase, it can be easily managed by medications. I feel confident giving it to patients who do not have glaucoma, but also to patients with glaucoma when it is well controlled by medications or after surgery. In chronic cases, with more than 3 years of persistent macular edema resistant to all other drugs, I would also consider Iluvien (fluocinolone acetonide, Alimera Sciences), which shows the best results in these cases.

I use steroids as a primary therapy in patients who cannot or are unwilling to come for monthly injections. Anti-VEGF therapy for DME requires monthly treatment at least for the first 3 to 6 months, and patients need to attend the clinic regularly to achieve and maintain the visual benefit. When treated with steroids, patients need to have IOP regularly checked, but this can be done by their local ophthalmologist. I also use steroids as primary therapy in patients who had a significant cardiovascular event, such as cardiac infarction or stroke, in the previous month or so. Although there is still debate on whether this is a contraindication to anti-VEGFs, I prefer not to use them in these cases. Currently, there is research underway on morphological markers showing if patients are most suitable for steroids. Presence of high quantities of hyper-reflective spots as a sign of inflammation may be one of these markers, but this has not yet been proven.

Anat Loewenstein, MD, is an OSN Europe Edition Board Member and director of the ophthalmology department at Sackler Faculty of Medicine, Tel Aviv University, Israel. Disclosure: Lowenstein reports she is a consultant to Allergan, Alcon, Bayer, Notal Vision and Novartis.