EyeWorld Asia-Pacific June 2023 Issue

Tackling myopia-associated glaucoma Myopia continues to be an increasing global healthcare issue, and accurate diagnosis and appropriate management remain challenging. With myopia and high myopia as risk factors for glaucoma and incident open-angle glaucoma (OAG), clinicians must be aware of how to handle these cases. Beginning with diagnosis, Wong Chee Wai, MD, PhD, noted fundus photography can be used to identify the pathology of high myopia and determine whether the cause is maculopathy or glaucoma. “Myopia macular degeneration (MMD) mainly affects the outer retina,” Dr. Wong said. “Look out for the external limiting membrane, the ellipsoid zone junction, and the retinal pigment epithelium.” He noted that it is important to perform optical coherence tomography (OCT) routinely in highly myopic eyes. Structural change was an important theme during this symposia session, and surgeons need to be cognizant of several details. Jin Wook Jeoung, MD, PhD, explained that in highly myopic eyes, the lamina cribrosa of the optic disc is significantly thinner and, in turn, decreases the distance between the intraocular space and the cerebrospinal fluid space. With the stretching of the optic nerve fibers during optic disc tilt and torsion, this eyeball elongation can lead to optic nerve head damage. Another factor in tackling high myopia is controlling intraocular pressure (IOP). “Changes in IOP influence axial length,” said Xiulan Zhang, MD, A 1 mmHg increase in IOP correlates to an increase of 0.1 mm in axial length. Lowering IOP can help high myopic patients and thus control axial length elongation. “A longer duration of using antiglaucoma medication is more effective in slowing axial length elongation,” said Dr. Zhang. “There is no blanket approach to treating patients,” said Ho Ching Lin, MD. She hopes that surgeons will treat each patient differently and exercise high caution in surgery, leaning towards safety. It is important to choose non-invasive options first before treating with surgery. As the prevalence of myopic cases rises, especially in the Asian population, the greatest changes patients may see with their vision is an enlarged blind spot and a generalized reduction in sensitivity. He Mingguang, MD, PhD, recommends always observing the fundus photography for changes in the optic disc and visual field. “Don’t forget to refer patients to a retinal specialist if necessary,” he reminded the audience. Everything Everywhere All at Once in the Cataract Metaverse This 2-part symposium gathered top phacoemulsification surgeons for a discussion on various techniques used in surgery and to answer, what happens when something goes amiss? John Wong, MD, began by sharing a unique situation. Upon entering the surgical room in the morning, he heard a loud humming from the ceiling vent and the room felt colder than usual. Although the temperature and humidity sensor readings were normal, Dr. Wong decided to proceed with his morning case. As the case progressed, though, his surgical view started to fog. Dr. Wong had to intermittently wipe the undersurface of the microscope, breaching the sterile field, until the surgery was complete. The humidity sensor had read 95%. No complications occurred, but Dr. Wong realized there was no anti-fog solution set up for emergencies like this. An anti-fog solution may consist of using isopropyl alcohol, surfactant, and water to lower the surface tension of the condensing surface. “In this part of the world, in the tropics, this is a real problem so this is very useful information,” Ronald Yeoh, MD, chair of the symposia, said. One member of the audience chimed in with a trick: “put a cloth in hot water, and place it under the microscope allowing it to become warm. The glass will never fog this way.” Surgical environment aside, Filomena Ribeiro, MD, PhD, stated that for patients with keratoconus, an implantable collamer lens (ICL) provides a safe and effective option. “ICL can provide very good quality of vision in patients with a stable condition. The problem we have is that we need to assess the correct sizing of these ICLs,” Dr. Ribeiro said. “We need to measure the posterior surface of the cornea. We need a map of the corneal power distribution.” Part 2 of Everything Everywhere All at Once in the Cataract Metaverse brought together even more cataract surgical discussions. Fluorescein eye staining has come a long way in the past two and a half decades. In 1904 trypan blue was introduced as the first anionic diazo dye in which its high molecular weight does not permeate cell membranes. “Trypan dye stains only dead cells; it doesn’t stain living cells,” Sathish Srinivasan, MD, said. “It very beautifully stains the anterior capsule and stays where we put it.” Unfortunately, one big issue with trypan blue is that the market is flooded with different brands of dye. Dr. Srinivasan explained that the most common impurity is monoazo dye; up to 1.7% of trypan dye may contain this impurity compared to

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