COVER STORY Surgery in Diabetic Patients Excellent outcomes can be achieved in these patients with appropriate attention to details.

BY UDAY DEVGAN, MD, FACS, FRCS(GLASG)

iabetes is an increasingly common systemic disease, and many patients seeking cataract surgery have coexisting diabetic disease. In D an otherwise healthy eye, modern cataract surgery can restore excellent vision and correct , hyperopia, and . But when there is coexisting diabetic , cataract surgery may put additional stress on the eye and can lead to , pro- gressive , and limited vision. Although it is still possible to deliver excellent results from cataract surgery in diabetic patients, these patients are at increased risk of complications and subsequent Figure 1. This patient has a quiescent with a preserved limitation of vision. With careful preoperative planning, macula due to successful and extensive panretinal photocoagu- attention to detail during phacoemulsification, and close lation performed nearly 20 years earlier.After cataract surgery postoperative supervision, diabetic patients can achieve she recovered excellent vision with a central acuity of 20/20. excellent vision after cataract surgery. macular edema, which is one of the principal causes of cen- PREOPERATIVE EVALUATION tral visual loss in these patients. A detailed dilated Diabetic patients receive the same type of preopera- examination can reveal many of these pathologies, but tive evaluation as other cataract patients but with more additional tests such optical coherence tomography (OCT) emphasis placed on the presence and extent of diabetic or angiography can reveal more subtle lesions. eye changes. Diabetic patients tend to develop Significant diabetic ocular pathology should be treated earlier and may be more prone to developing posterior before cataract surgery is considered. This involves a mul- subcapsular cataracts than other patients, so they often tifaceted approach with argon laser panretinal photoco- present with cataracts at an earlier age. It is important to agulation as the primary treatment for proliferative establish that the degree of cataract seen corresponds to retinopathy (Figure 1) and focal macular laser for clinical- the patients’ and reported visual dysfunc- ly significant macular edema. Additional treatment often tion. If the patient reports severe vision problems but the involves of vascular endothelial exam shows mild cataracts, one must look carefully at growth factor (VEGF) inhibiting medications and the retina for other causes of visual loss. steroids. The patient should also be counseled to achieve can be broadly divided into two tight control of systemic , and this should categories: background diabetic retinopathy and prolifera- be demonstrated in the patient’s hemoglobin A1c level. tive diabetic retinopathy. One of the key differentiating fac- For patients with significant diabetic retinopathy, my tors is the presence of harmful . The preference is to work with my vitreoretinal colleagues. growth of new vessels can lead to a host of subsequent Once the diabetic eye disease is sufficiently controlled, problems, including , tractional retinal the patient is referred back to me for cataract surgery. detachment, and neovascular . Diabetics any at The anterior segment can also be negatively affected stage of the spectrum of retinopathy are susceptible to by poorly controlled . Effects can include neovas-

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surgery may lead to progression and worsening of retinopa- thy, which can have detrimental effects on vision. In with minimal diabetic changes, cataract surgery is not as likely to cause progression of retinopathy. Therefore, performing cataract surgery at an earlier stage is often beneficial for dia- betic patients because it is associated with fewer complica- tions and better postoperative recovery of sharp vision. In my practice, I advise diabetic patients to address their cataracts early, when their retinal status is more likely to be normal.

Figure 2. Anterior segment neovascularization such as the THE POSTOPERATIVE COURSE pictured here is a sign of and typical- Postoperatively, topical steroids and nonsteroidal anti- ly accompanies ocular comorbidities such as neovascular inflammatory drugs (NSAIDs) are prescribed because they glaucoma and proliferative diabetic retinopathy. control inflammation and may play a role in the preven- tion and treatment of macular edema. Macular thickness cularization of the and angle, which often leads to can be evaluated at serial postop visits via OCT before the neovascular glaucoma. Aggressive treatment of neovas- topical medications are stopped. Patients should aim to cular glaucoma must take priority over cataract treat- keep their systemic blood glucose levels controlled during ment because prolonged increase in the postoperative period to aid with healing. can cause permanent damage to the optic and Development of posterior capsular opacification and severe visual loss. Teamwork with a retinal colleague is persistent postoperative inflammation may be more com- often the best approach in these complex patients. mon in diabetics. Despite a beautifully performed cataract surgery, diabetic retinopathy can become exacerbated in SURGICAL TECHNIQUE AND FOLLOW-UP the postoperative period, so patients should be monitored Once the diabetic retinopathy is quiescent and the mac- closely with serial dilated funduscopic examinations and ula is dry, cataract surgery can be planned. Intraocular referred to retinal colleagues as needed. (IOL) preference should lean to monofocal, toric, or some- Diabetic patients with visually significant cataracts pose times accommodating IOLs. Multifocal IOLs should be unique challenges during surgery, and they may be prone avoided in eyes with a history of macular lesions or the like- to a more difficult postoperative recovery. However, with lihood of developing macular pathology. Acrylic IOLs are careful pretreatment of the diabetic retinopathy, minimally preferred for patients who are likely to undergo traumatic surgical techniques, and appropriate postopera- for proliferative diabetic retinopathy in the future, whereas tive medications, these patients can do very well and silicone IOLs may be a reasonable choice in patients with recover excellent vision just like other cataract patients. ■ well-controlled diabetes and mild retinopathy. Steps to make cataract surgery less traumatic include Uday Devgan, MD, FACS, FRCS(Glasg), is in minimizing phaco energy, running less fluid through the private practice at Devgan in Los eye, and avoiding contact with the iris. Efficient surgical Angeles, Beverly Hills, and Newport Beach, CA. technique is important to achieve optimal results of He is also Chief of at Olive View cataract surgery in diabetic patients. These complex UCLA Medical Center and an Associate Clinical patients do better when surgery is performed by a more Professor at the UCLA School of Medicine. Dr. Devgan can experienced surgeon rather than a novice. Diabetic eyes be reached at +1 800 337 1969; fax: +1 310 388 3028; often have poor pupillary dilation, particularly when active Web site: www.DevganEye.com; or via e-mail at rubeosis iridis (Figure 2) or even regressed neovasculariza- [email protected]. Dr. Devgan states that he has no tion is present. stretching should be avoided because financial disclosure relevant to the content of this article. these vessels can rupture and cause intraocular bleeding. For further reading: In some cases, intravitreal injection of or Chew EY, Benson WE, Remaley NA, et al. Results after lens extraction in patients with diabetic retinopathy: Early Treatment Diabetic Retinopathy Study Report Number 25. Arch Ophthalmol. anti-VEGF medications is given at the time of or before 1999;117:1600-1606. cataract surgery. For diabetic patients with nonclearing vit- Dowler J, Hykin PG. Cataract surgery in diabetes. Curr Opin Ophthalmol. 2001;12:3:175-178. Mittra RA, Borrillo JL, Dev S, et al. Retinopathy progression and visual outcomes after pha- reous hemorrhages or tractional retinal detachments, coemulsification in patients with diabetes mellitus. Arch Ophthalmol. 2000;118:912-917. Squirrell D, Bhola R, Bush J, et al. A prospective, case controlled study of the natural history cataract surgery can be combined with a pars plana vitrec- of diabetic retinopathy and after uncomplicated phacoemulsification cataract tomy in a team approach with a vitreoretinal colleague. surgery in patients with . Br J Ophthalmol. 2002;86:565-571. Straatsma BR, Pettit TH, Wheeler N, Miyamasu W. Diabetes mellitus and In eyes with very significant diabetic retinopathy, cataract implantation. Ophthalmology. 1983;904:336-343.

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