Safer surgery, better diagnostics are focus

San Francisco-Developments in the area of glaucoma devices include new technology for surgical solutions and advances in imaging platforms. Speakers provided an update on ongoing research during a session moderated by Alan Crandall, MD.

David Applegate, vice president, marketing and business development, Glaukos Corp., said Glaukos, the founder of microinvasive glaucoma surgery (MIGS), has developed a platform of MIGS technology.

“MIGS is ab interno, takes advantage of natural physiological outflow pathways, involves a microincision <1 mm, and has a strong safety profile,” Applegate said. “Our company has a full glaucoma stent franchise and pipeline and we hope to be able to treat the entire range of open-angle glaucoma over the next few years.”

An FDA panel recommended approval of its first-generation device (iStent) in July 2010. A second-generation device (iStent inject) has the same mechanism of action as the iStent but is designed to go through a smaller paracentesis and could potentially be used in a closed chamber procedure. A third-generation product (iStent SUPRA) is placed in the suprachoroidal space and is envisioned for use primarily as an enhancement after trabecular meshwork procedures. Both the second- and third-generation devices are in expanded U.S. IDE registration trials. Together, the three devices are being investigated in a total of 18 ongoing clinical trials in 14 countries.

Brian Welch, chief executive officer (CEO) and president, Transcend Medical, said his company believes its microstent device (CyPass) will help address an unmet clinical need in glaucoma. The microstent has a 300-μm lumen and is delivered into the supraciliary space using a guidewire.

There are more than 500 patients in the CyPass database from three trials in Europe, and a randomized IDE trial was initiated in the United States a few years ago. Welch showed data from one European trial that demonstrated whether the device is placed alone or in combination with cataract surgery, it is associated with sustained IOP reduction for at least 12 months with a concomitant reduction in medication need and excellent safety results.

Recently, the company developed a goniometric system that allows for gonio-free insertion of the technology.

“This would convert the surgery from a dual-handed procedure to a single-handed operation performed with the patient in the cataract position,” Welch said. “We think this is a highly significant advancement for microincisional surgery.”

Development of site-specific ophthalmic access technologies is the focus of research at iScience, said Michael F. Nash, president, CEO, and director.

The canaloplasty microcatheter (iTrack), the company’s first platform, has already been used in more than 19,000 canaloplasty procedures worldwide, and outcomes data show the surgery results in significant reduction of IOP and medication use that is sustained over 3 years.

There is also interest in using the microcatheter to enable delivery of pharmaceutical candidates and biologics to Schlemm’s canal. In addition, the company is developing suprachoroidal and subretinal access technology. Interest in the suprachoroidal space relates in part to the idea it may be a pathway to the optic nerve.

“The access technology revolution is just beginning,” Nash said. “We believe site-specific management of disease will redefine how future treatment is done for ophthalmology.”

NeoMedix Chief Operating Officer Michael Mittelstein, PhD, provided an update on a novel device (Trabectome), which is used to re-establish the natural drainage system of the eye by ablating tissue from the trabecular meshwork and Schlemm’s canal. He noted the device received FDA approval 6 years ago and has been used in about 12,000 surgeries worldwide.

In 2004, the company launched a postmarketing surveillance program in which surgeons were asked to submit data voluntarily on their first 20 cases. Data have been collected on about 3,500 patients with a minimum of 3 months follow-up who represent a heterogeneous group with respect to age, glaucoma type, and prior interventions.

Analyses of the data show IOP is significantly reduced and remains stable with follow-up to 6 years. Mean medication use has been reduced from three agents to just one, and other than transient issues, there have been few complications.

“This is a low-risk procedure that is not difficult to teach and learn and involves no conjunctival manipulation,” Dr. Mittelstein said. “In the treatment triad for glaucoma, it may fit between laser procedures and incisional surgeries. However, some of our surgeons would even argue that it be considered at an earlier stage, before a laser procedure, because of its very good side effect profile and durable results.”

In 2006, Optovue marketed the first Fourier-domain optical coherence tomography (FD-OCT) platform (RTVue) in the United States, and it has continued on a path of innovation, said Jay Wei, founder, president, and CEO.

The company has also introduced a fully portable FD-OCT platform (iVue) and products to expand its clinical utility (iStand and iWellness).

Reviewing the pipeline, Wei said the company is excited about full-range OCT that doubles the scan depth relative to conventional OCT without compromising scanning speed or resolution. This technology is expected to have applications in glaucoma as well as refractive and cataract surgery.

In addition, the company has licensed a motion-free correction algorithm from MIT to create images without distortion from eye movement.

“This is a critical development for improving disease monitoring,” Wei said.

Doppler OCT that can measure blood flow around the optic nerve is being studied, and higher speed and swept-source technology are in development.

Concept Imaging was founded in 2003 with an initial focus on developing noninvasive glucose monitoring for diabetics through optical analysis. Along the way, it invented multiple-reference OCT (MRO-OCT), an inherently small, low-cost, flexible variant of time-domain OCT, and in 2011, the company changed its focus to bring this technology to market, said Don Bogue, CEO.

Research so far demonstrates the capability of the platform to image features of interest and collect information needed to make measurements. Signal processing development is continuing to improve image quality. The company has built a comprehensive IP foundation underneath the architecture and is aiming to conduct its first clinical test on a live subject this year.

Bogue suggested MRO-OCT could be used by primary-care practitioners for routine screening and monitoring to guide decisions about patient referrals for specialist care.

“We believe MRO-OCT creates new opportunities in eye care,” Bogue said. “With its cost, size, and ability to make clinically significant measurements, MRO-OCT will make ophthalmic diagnostics more accessible.”

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