When cataract surgery is indicated in patients with retinal pathologies, one potential source of intra- and postoperative complications is the inflammation that is generated in response to surgical trauma. Eyes with age-related macular degeneration (AMD), diabetic retinopathy, chorioretinitis, and vitreoretinal interface syndrome are especially challenging environments in which to perform cataract surgery due to the inflammatory origins of these pathologies. Following a rigorous protocol for patient preparation, surgical technique, and postoperative control can help to minimize the risks for complications and achieve good postoperative outcomes.
The protocol for cataract surgery in patients with retinal pathologies has four basic components: (1) select an approach that will permit the best control of the retinal disease and minimize surgical trauma; (2) prescribe appropriate medications before surgery; (3) do not delay surgery, thus preventing cataracts that make surgery more difficult; (4) and establish strict postoperative control, focusing on inflammation and macular appearance.
Examine the peripheral and central retina as thoroughly as possible preoperatively. If the periphery can be visualized, look for suspicious zones that could potentially induce retinal detachment. If any are found, apply laser photocoagulation before cataract surgery.
In eyes with suspected or confirmed macular membranes, cystoid macular degeneration, diabetic macular edema (DME), or other macular pathologies that are likely to experience further decompensation after cataract surgery, we recommend intravitreal injection of a vascular endothelial growth factor (VEGF) inhibitor approximately 2 to 4 days before surgery or at the end of surgery. In patients with diabetes, we always recommend injection of a VEGF inhibitor before or during surgery, even in eyes with no evidence of DME.
We often perform phacovitrectomy in patients with epiretinal membranes to reduce surgical trauma with one surgical event rather than two and reduce functional recovery time. Our current preference is phacovitrectomy with either conventional 20-gauge vitrectomy or transconjunctival sutureless vitrectomy.
In eyes with retinitis or macular dystrophy and cystoid macular edema (CME), at the end of surgery we insert a slow-release intravitreal drug implant such as Ozurdex (dexamethasone intravitreal implant; Allergan, Inc.) or Retisert (fluocinolone acetonide intravitreal implant; Bausch + Lomb) to control inflammation.
We recommend low-flow microincision cataract surgery (MICS) in eyes with retinal pathologies. Studies have shown that, because MICS is less aggressive than standard cataract surgery, it causes less damage to intraocular structures. 1-6 Therefore, there is less endothelial cell loss, less inflammation in the anterior segment, and a lower level of cytokines passing from the anterior to the posterior segment, which results in less inflammation in the macula.
Our introduction to bimanual MICS occurred more than a decade ago, when we experimented with the Er:YAG laser for cataract surgery.7 Although this technology did not work well, it allowed us to learn about bimanual MICS and introduced us to new instruments and techniques to reduce surgical trauma, including the use of very low flow parameters. With modern ultrasound platforms such as the Stellaris Vision Enhancement System (Bausch + Lomb), Constellation (Alcon), and Whitestar Signature (Abbott Medical Optics Inc.), and with axial, lateral, or circular phaco-needle oscillation, ultrasound power between 5% and 10% can sufficiently emulsify even grade +4 cataracts.
When less ultrasound energy is used, there is lower axial displacement of the needle and, thus, less chattering. Therefore, we can reduce the amount of vacuum needed to fixate nuclear fragments and the amount of irrigation needed to control the surge induced by the opening of the suction line. This is the basis for low-flow surgery, which can be used to avoid the scenario detailed in Figure 1.
Because bimanual MICS requires less volume of flow in the anterior segment, tissue trauma is reduced during surgery. Bimanual MICS also provides better control of surgical maneuvers and creates a more stable anterior chamber because it requires less vacuum. Since adopting a bimanual MICS technique for eyes with retinal pathologies, our percentage of retinal complications has decreased, especially macular edema.
Rigorous follow-up is essential to minimize inflammation after surgery. We prescribe a combination of steroids such as Pred Forte (prednisolone acetate; Allergan, Inc.) and topical NSAIDs such as Nevanac (nepafenac; Alcon) applied daily for at least 3 weeks, with NSAID treatment continued for up to 3 months postoperatively. We also recommend injection of an anti-VEGF agent at 1 month postoperative and schedule follow-up care by the retina unit.
Carlos Vergés, MD, PhD, is a Professor and the Director of Area Oftalmológica Avanzada, Politecnic University of Catalonia, Barcelona, Spain. Dr. Vergés states that he has no financial interest in the products or companies mentioned. He may be reached at e-mail: firstname.lastname@example.org.
Joan Casado, MD, is the Director of the Retina Unit, Area Oftalmológica Avanzada, Barcelona, Spain. Dr. Casado states that she has no financial interest in the products or companies mentioned. She may be reached at e-mail email@example.com.
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- Kurz S, Krummenauer F, Gabriel P, Pfeiffer N, Dick HB. Biaxial microincision versus coaxial small-incision clear cornea cataract surgery. Ophthalmology. 2006;113:1818-1826.
- Kurz S, Krummenauer F, Thieme H, Dick HB. Biaxial microincision versus coaxial small-incision cataract surgery in complicated cases. J Cataract Refract Surg. 2010;36:66-72.
- Mencucci R, Ponchietti C, Virgili G, Giansanti F, Menchini U. Corneal endothelial damage after cataract surgery: Microincision versus standard technique. J Cataract Refract Surg. 2006;32:1351-1354.
- Mojzis P, Piñero DP, Studeny P, et al. Comparative analysis of clinical outcomes obtained with a new diffractive multifocal toric intraocular lens implanted through two types of corneal incision. J Refract Surg. 2011;27:648-657.
- Moore SP, Goggin M. Intraoperative floppy iris syndrome and microincision cataract surgery. J Cataract Refract Surg. 2009;36:1008-1015.
- Vergés C, Llevat E. Laser cataract surgery. Technique and clinical results. J Cataract Refract Surg. 2003;29:1339-1345.