A 54-year-old female was referred by her primary eye-care provider seeking a refractive surgical solution for troublesome presbyopia and progressive evening dysphotopsia. Her refractive history included moderate myopia and a growing intolerance to bifocal correction. She had been wearing soft contact lenses for 16 hours per day with readers as needed and was also developing significant dry eye and discomfort with her contact lens regimen.

The patient's ocular history was complicated by mild primary open-angle glaucoma (POAG), for which she had taken latanoprost nightly at bedtime for more than 2 years. Visual acuity testing revealed a best-corrected visual acuity of 20/20- in the right eye and 20/25 in the left, with glare disability of 20/50 and 20/60, respectively. Intraocular pressure (IOP) was measured at 13 mmHg in the right eye and 15 mmHg in the left eye. Ocular examination revealed healthy ocular surface and cornea, a 1+ nuclear sclerotic cataract with 2+ cortical spoking, and a healthy retina. The optic nerve showed a cup-to-disc ratio of 0.8 in both eyes, and ancillary testing revealed significant retinal nerve fiber layer (RNFL) deficits on optical coherence tomography (OCT) of both eyes, consistent with anatomically advanced glaucoma (Figure 1). Visual field testing was normal without defect in either eye.

Diagnosis

This patient had mild POAG, early but visually significant cataract, and a deep desire to reduce her dependence on glasses and contact lenses. Although she had no detectable visual field deficits on standard automated perimetry, her anatomic exam, including RNFL loss on OCT, was significantly advanced given her relatively young age. Her IOP was noted at an acceptable level compared to her previously reported maximum.

Treatment

After ruling out a cornea-based refractive surgery for this patient, attention was turned to the management of the patient’s cataract. This type of case presents a commonly encountered scenario in our clinic due to parallel offerings of refractive surgery and comprehensive glaucoma care. However, I would also believe this to be an increasingly encountered scenario in many practices across the country due to the earlier surgical management of glaucoma (largely thanks to the success of minimally invasive glaucoma surgery, or MIGS) coupled with the rapid advancement in quality of presbyopia-correcting intraocular lenses (IOLs). Common practice among ophthalmologists has long been to decouple the management of a patient’s glaucoma and refractive desires: if there is optic nerve disease present, patients are simply relegated to receiving a conventional approach to cataract surgery and destined for bifocals. And this was largely considered in the best interest of the patient, given concerns that any refractive or light-splitting optic within the eye may compound the anticipated reduction in contrast sensitivity in the future. Surgeons might have reported that it felt taboo to consider anything other than a monofocal lens, or maybe the occasional toric, for a glaucoma patient during cataract surgery.

A Paradigm Shift

Newer generation IOLs have brought new life to refractive cataract surgery and with it a potential expansion in patient application. Although it is true that diffractive lens types almost by nature result in at least some reduction in modulation transfer function (clinically, this may be seen as reduced contrast sensitivity) compared to monofocal,¹ the effect of this on the visual function of patients is a matter of debate. In a paper presented at the ASCRS meeting in 2019, our group highlighted a case-control study of 80 eyes with mild-moderate open-angle glaucoma that had been implanted with diffractive extended range of vision IOLs (Tecnis multifocal or Symfony [Johnson & Johnson Vision]) or a monofocal lens.² In the study, we reported no difference in change in standard automated perimetry performance (mean deviation [MD]) before and after surgery in the study group vs the control, indicating that, at least to the extent that common glaucoma performance metrics can determine, contrast sensitivity reduction does not seem to impact the results of functional glaucoma testing in these patients. Similarly, a recently published article by Takahashi et al found no significant difference in MD or foveal threshold in patients with glaucoma who were implanted with extended depth of focus (Tecnis Symfony) vs monofocal lens.³

In recent years, additional lens options have become available to cataract surgeons and their patients, including a newer generation extended depth of focus lens from Alcon, the AcrySof IQ Vivity IOL. The extension of the patient’s depth of field, or EDOF effect, in this lens is created not by the light-splitting of a diffractive optic, but instead by “surface transition elements” on the anterior surface said to alter the shape of the incident wavefront.⁴ The appeal of such a lens is significant for refractive cataract and glaucoma surgeons alike. In the US clinical trial, researchers found a significant reduction in monocular contrast sensitivity in the Vivity lens compared to a monofocal lens.⁵ However, in a separate clinical study, there was no difference in binocular contrast sensitivity found compared to a monofocal control.⁴ Thus, the functional clinical impact on such optics is unknown. Impressively, the Vivity lens (Alcon) has demonstrated a similar dysphotopsia profile to a monofocal lens,⁵ and patients with Vivity reported “good quality of vision” in both dim and light conditions,⁵ which is a promising result for a new technology aimed at application to a wider range of patients.

Case Outcome

Returning to our patient with mild POAG, cataract, and a desire for spectacle independence, we were faced with the task of helping her accomplish her own refractive goals, while keeping in mind her ocular comorbidity and being good stewards of future ocular health. After thorough discussion with the patient, we elected to use the Alcon Vivity EDOF lens and place the iStent Inject from Glaukos in both eyes at the time of surgery, aiming to improve long-term ocular surface health by reducing her drop burden (Figure 2). At 1 month follow-up, the patient had excellent uncorrected distance vision and was very happy with her new ability to function at distance and near without the use of glasses, as well as being drop free. GP

Brandon Baartman, MD, is an anterior-segment and glaucoma specialist at Vance Thompson Vision in Omaha, Nebraska. Dr. Baartman reports that he is a consultant to and investigator for SightSciences, and an investigator for Glaukos. Reach him at brandon.baartman@vancethompsonvision.com.

References

1. Zhao G, Zhang J, Zhou Y, Hu L, Che C, Jiang N. Visual function after monocular implantation of apodized diffractive multifocal or single-piece monofocal intraocular lens Randomized prospective comparison. J Cataract Refract Surg. 2010;36(2):282-285. doi:10.1016/j.jcrs.2009.08.037. PMID: 20152611
2. Baartman BJ, Berdahl JP. Comparing visual field change in eyes receiving multifocal or extended-range-of-vision implants in patients with glaucoma. Paper presented at the annual meeting of the American Society of Cataract and Refractive Surgeons; May 6, 2019; San Diego, CA.
3. Takahashi M, Yamashiro C, Yoshimoto T, et al. Influence of extended depth of focus intraocular lenses on visual field sensitivity. PLoS One. 2020;15(9):e0237728. Published 2020 Sep 14. doi:10.1371/journal.pone.0237728
4. Schwiegerling J, Gu X, Hong X, Lemp-Hull J, Merchea M. Optical principles of extended depth of focus IOLs [white paper]. Alcon Vision. Accessed June 28, 2021. https://us.alconscience.com/sites/g/files/rbvwei1736/files/pdf/Optical-Principles-of-EDOF-US-CAT-2000006.pdf
5. Alcon AcrySOF IQ Vivity Lens DFU. Accessed June 28, 2021. https://www.accessdata.fda.gov/cdrh_docs/pdf/P930014S126B.pdf