Ep. 4 Prof Barrett: Developing RayOne EMV and the Barrett Universal Formula


Dr Karl Stonecipher (host)
Dr Karl Stonecipher is the medical director of TLC Greensboro in North Carolina and a clinical associate professor of Ophthalmology at the University of North Carolina. Dr Stonecipher has over 100 abstracts, articles, and book chapters published, and speaks both nationally and internationally on refractive, cataract, presbyopic and refractive surgery.

Professor Graham Barrett (guest)
Professor Graham Barrett is a consultant ophthalmologist at the Lions Eye Institute as well as Sir Charles Gairdner Hospital in Perth Western Australia and is a clinical professor in the University Department of Ophthalmology of Western Australia. His special areas of interest include cataract and implant surgery, as well as corneal and keratorefractive surgery. Professor Barrett is also the founding and current President of AUSCRS.



In this episode of ‘Peer2Peer: The Podcast’, Dr Karl Stonecipher (United States) sits down with Professor Graham Barrett (Australia) — collaborator on Rayner’s RayOne EMV enhanced monofocal IOL — and asks him about the concept behind RayOne EMV. Professor Barrett also discusses why he chose to use positive spherical aberration to provide patients with extended depth of focus, the patient selection process, and why he thinks RayOne EMV is suitable for almost anyone.


Key Takeaways:

  • RayOne EMV uses positive spherical aberration which interacts synergistically with myopia to give an extended range of vision without impacting distance vision.
  • Professor Barrett discovered that using positive spherical aberration with myopia achieves a better quality of vision.
  • If surgeons are unsure about using RayOne EMV on a patient, Professor Barrett suggests checking the amount of spherical aberration in the eye and being cautious if it nears +0.3 to +0.4 microns.
  • Professor Barrett believes the RayOne EMV lens is suitable for almost anyone.
  • Today, many patients are more concerned with being spectacle free for intermediate vision, so that they can use their smart phones and tablets.


Additional Resources:

Peer2Peer educational platform

My Next Ophthalmologist Needs No Introduction: Ep 2 with Prof Barrett

Overcoming the Limitations of Conventional Monovision with New Extended Depth of Focus Lenses

The Best of Both Worlds by Professor Graham D Barrett


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