PUBLICATION EXCLUSIVE: OCT screening before cataract surgery: Three must-know diseases

With the advent of OCT, we can examine the retina, particularly the macula, in high resolution before cataract surgery. This is important because the cataract may not be the sole cause of visual impairment, and patients need to have appropriate expectations set before cataract surgery.

OCT makes it easy to identify subtle macular changes that may not be apparent when the fundus is examined clinically. Using the principle of optical interferometry, these devices acquire sharp, high-resolution views of the retina even when there is dense media opacity.

There are three must-know retinal conditions that should be identified before planning phacoemulsification surgery. As a cataract surgeon, to keep abreast of the advances in retinal imaging, I rely on sites such as EyeGuru.org, which has provided the cases featured below.

No. 1: Macular degeneration

Consider the following case (Figure 1): Our patient arrives for preoperative evaluation with 20/80 best corrected vision that does not improve with pinhole. He has a visually significant cataract with moderate nuclear sclerosis and an unremarkable fundus exam with a somewhat hazy view of the retina. Cataract surgery is recommended, which he undergoes without complication. Postoperatively, he achieves 20/40 best corrected vision. At this point, careful macular exam shows subtle pigmentary changes and some drusen. OCT shows a fibrovascular pigment epithelial detachment without retinal edema, which accounted for his suboptimal visual outcome.

Patients with macular degeneration, whether the dry or wet form, can have an insidious course of disease without the classic presentation of metamorphopsia and blurry vision. Even dry macular degeneration can be associated with localized dysfunction of the retinal photoreceptors and can account for several lines of vision loss. Paracentral focal areas of atrophy can be difficult to discern in a blonde fundus. These changes can easily be overlooked, and the visual decline may be inappropriately attributed to the cataract. It may be beneficial to perform an OCT if there is any doubt of drusen or pigmentary changes or if the view from the cataract is sufficiently poor to preclude fine macular exam.

Click here to read the full publication exclusive, Back to Basics, published in Ocular Surgery News U.S. Edition, April 25, 2017.