Investigational treatment seeks to reverse presbyopia, restore natural accommodation

Investigational treatment seeks to reverse presbyopia, restore natural accommodation

ONLINE EXCLUSIVE

Refractive
November 2023

by Liz Hillman
Editorial Co-Director

The holy grail of presbyopia is to restore the eye’s natural ability to dynamically focus for any visual task, including accommodation to focus at near and disaccommodation to focus at far and every distance between. Current viable options for patients with presbyopia include corneal substitutionary procedures involving multifocality, monovision, or refractive lens exchange. These current options do not treat the fundamental problem of presbyopia, which is age. Since presbyopia is progressive, only dynamic solutions will be able to meet every patient where they are in the aging cycle. Readers are a viable option since the patient can increase their reading add with age. Multifocal contact lenses are also able to address the problem but are not tolerated by many. None of the options, from readers to intraocular lenses to monovision techniques to drops, according to John Marshall, PhD, FRCPath, FMedSci, restore full dynamic range of focus for vision.

However, there is work being performed by Ace Vision Group on laser scleral microporation, a technique that Prof. Marshall, who is on the company’s Scientific Advisory Board, thinks could “rejuvenate” the eye’s natural dynamically focusing process.

Dynamic range of focus, Dr. Marshall said, is the seamless ability to dissaccommodate, to see things clearly in the distance and accommodate quickly to see at intermediate or near. “It is a smooth, imperceptible motion, which the brain, while ultimately in control of the process, does not perceive,” he said. There are several reasons why the loss of this dynamic range of focus occurs. These commonly include: 1) the lens getting too stiff and too big to deform for disaccommodation and accommodation adequately; 2) the ciliary muscles that trigger accommodation are becoming less efficient; and 3) the zonules lose tension and become slack. However, another factor is less discussed, Prof. Marshall said.

“Until recently, what most people have ignored is that accommodation is not only the inward and forward movements of the ciliary processes to allow the lens to change shape, but there is also a component that pulls the lens back in order to shift to distance vision,” he said. “That comes about because some of the fibers of the zonules leave the lens and pass through the valleys in the pars plicata where they insert but other zonules pass all the way over the pars plana and actually insert near Bruch’s membrane. When the ciliary muscles are moving forward, this system is under tension. When accommodation is relaxed, Bruch’s membrane undergoes target recoil and pulls back. Now, these components are also undergoing aging. Both Bruch’s membrane and sclera are getting stiffer because of age-related crosslinking, and this aging process degrades target recoil because its components are getting stiffer and stiffer, and you get less and less of a target recoil effect as you age.” This is where laser scleral microporation, LSM Laser Eye Therapy—creating “micropores” in the sclera over the ciliary muscles, according to Ace Vision Group—comes into play.

“What the microporation is doing is actually uncrosslinking,” Dr. Marshall said. “Removing small amounts of tissue in a programmed way allows this target recoil of Bruch’s membrane and the choroid to function near to its useful state.”

As the company states, LSM Laser Eye Therapy is:

  • A non-invasive, in-office, therapeutic treatment that restores dynamic range of focus for the presbyopic patient in a natural way.
  • Innovative laser technology offering unique touchless eye laser therapeutic solutions for the aging eye.

Ace Vision Group conducted preliminary pilot studies using the VisioLite Erbium YAG (Er:YAG) Ophthalmic Laser System, outside of the U.S. The VisioLite Ophthalmic Laser System and LSM Laser Eye Therapy are not yet FDA approved or available in the U.S. It is currently in pilot studies only in select areas outside the U.S. Safety and efficacy results from a 24-month pilot study in 50 patients have been the subject of several recent congress presentations conducted by Robert Ang, MD, at the Asian Eye Institute:

  • Improvements of VA: Patients gained more than two lines of near visual acuity immediately after the procedure, improving from 0.45 to 0.20 logMAR at 3 months. 
  • Dependence on reading glasses: Reading add improved significantly, reducing dependence on reading glasses.
  • Sustained over 2 years: Significant improvements in near visual acuity, reading add, patient reported outcomes and IOP were sustained at least 2 years.

Prof. Marshall said he thinks the initial results with the treatment are “very satisfactory, showing that this concept, the hypothetical issue, is in fact reality and is working.

“This is rejuvenating the process. It’s taking the natural process, which has fatigued with age, and setting it back 10, 20, 30 years,” he said, noting that unlike other options on the market to treat the effects of presbyopia, the microporation treatment restores the truly dynamic process vs. bridging it with what he called “stop-click” technologies that don’t have smooth, dynamic focusing.

About the physician

John Marshall, PhD, FRCPath, FMedSci
Frost Professor of Ophthalmology
University College London
London, U.K.

Relevant disclosures

Marshall: None

Contact

Marshall: eye.marshall@googlemail.com

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