Glaucoma Renaissance: New Medical and Surgical Treatments for Glaucoma

Glaucoma Renaissance: New Medical and Surgical Treatments for GlaucomaMan getting eye exam

Gagan Sawhney, MD, Georgia Eye Partners

Despite significant progress made in the fight against glaucoma, the human cost of this disease remains unacceptably high. According to the World Health Organization, glaucoma is the second leading cause of blindness worldwide. While we’ve managed to reduce the long-term probability of going blind in one eye from glaucoma to 13.5% from 25.8% in recent decades, a significant portion of patients still progress to blindness. It is estimated that within the United States alone, there will be more than 3 million cases of open-angle glaucoma by 2020, with more than 88,000 of these patients going blind. As a glaucoma specialist who sees over 60 patients a day, this is a terrifying statistic. Unfortunately, glaucoma is still a leading cause of blindness even under our care.

Why does glaucoma still present such a therapeutic challenge? First, it is underdiagnosed. We are missing early disease, and once damage is done, it cannot be reversed. Second, when we do diagnose and begin to treat glaucoma, too often we are not reaching target pressures, or not setting them low enough to begin with.

Third, when we do treat adequately, lack of compliance often impedes outcomes. The need to take multiple therapies several times a day, as well as the topical and systemic adverse events associated with those therapies, affect patients’ ability to take medications as prescribed.

Fortunately, we are living a glaucoma renaissance, and there have been numerous new medical and surgical treatments for glaucoma in the last two to five years.

NEW MEDICATIONS

RHOPRESSA

Approved by the FDA in December 2017, Rhopressa (netarsudil ophthalmic solution) 0.02% is the first in a new class of glaucoma medications called Rho kinase (ROCK) inhibitors. ROCK activity inhibition is thought to prevent contraction of trabecular meshwork stress fibers and reduce resistance to aqueous humor outflow by disrupting actin-myosin contraction, decreasing extracellular matrix production and relaxing the tissue. Rhopressa is the first glaucoma medication to improve trabecular meshwork outflow through this unique mechanism.

In addition to targeting the trabecular meshwork, there is evidence that suggests Rhopressa also reduces aqueous production via norepinephrine transporter inhibition2 and lowers episcleral venous pressure by ROCK inhibition.3

VYZULTA

Approved by the FDA in November 2017, Vyzulta (latanoprostene bunod ophthalmic solution) 0.024% is the first prostaglandin analog with one of its metabolites being nitric oxide (NO), is indicated for the reduction of intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension.

Vyzulta is novel in that it has two primary mechanisms of action. Following topical administration, Vyzulta, a once-daily monotherapy, works within the uveoscleral pathway to increase aqueous humor outflow, and increases outflow through the trabecular meshwork and Schlemm’s canal via its nitric oxide component.

NEW SURGICAL DEVICES: MINIMALLY INVASIVE GLAUCOMA SURGERY

Minimally invasive glaucoma surgery (MIGS) is the latest advancement in glaucoma surgical management and refers to a group of procedures that aims to decrease intraocular pressure by limiting risks and complications that are typically associated with traditional glaucoma surgery.

For a procedure to be classified as minimally invasive, it needs to adhere to a certain set of criteria. 1)  Minimally traumatic, 2) Rapid Recovery, 3) High Safety Profile, and 4) Modest Efficacy in lower intraocular pressure.

The advantage of MIGS is that it can lower eye pressure safely, reduce pressure fluctuations, improve compliance because treatment does not rely on the patient, and result in better quality of life by potentially reducing the number of topical glaucoma medications.

MIGS: ISTENT INJECT

The iStent Inject is a second-generation device that consists of two small, titanium stents (less than 0.5mm). It is designed to optimize the natural physiological outflow of aqueous humour by creating two patent bypasses through the trabecular meshwork, the main source of resistance in glaucomatous eyes. The stents are surgically implanted into the drain of the eye via a micro-incision to help promote fluid outflow, thereby lowering intraocular pressure. Currently, the iStent inject can only be implanted in patients with mild to moderate glaucoma who are also undergoing cataract surgery. Clinical studies demonstrate that most patients experience reduction in IOP and a reduction in reliance on glaucoma medications.

MIGS: HYDRUS MICROSTENT

The Hydrus Microstent is an implantable, super elastic, biocompatible alloy that is roughly the size of an eyelash. It is intended to reduce eye pressure by acting as a support structure in one part of the natural drainage pathway of the eye. The microstent acts as a scaffold that is inserted into the primary fluid drainage canal and opens the channel to allow blocked fluid to flow more freely, thus reducing high IOP. The procedure required to implant the Hydrus scaffold is designed to be quick, and less invasive than traditional glaucoma surgery. The microstent is currently indicated for patients with mild to moderate open angle glaucoma who are undergoing cataract surgery.

MIGS: XEN GEL STENT

The Xen Gel Stent is the first minimally invasive glaucoma surgery to create a new pathway for aqueous flow from the anterior chamber to the subconjunctival space in refractory glaucoma patients. The XEN Gel Stent is a surgical implant designed to lower high eye pressure in open-angle glaucoma patients where previous surgical treatment has failed and/or medications alone were insufficient (also known as refractory glaucoma). The gel stent is 6-mm length, 45-micron lumen diameter, roughly about the length of an eyelash. The Xen gel stent reduced mean IOP by ≥ 25% in 80.8% of eyes with minimal adverse event profile.

CONCLUSION

Glaucoma patients are very fortunate today as we are living in a glaucoma renaissance where new medications, new modalities of medication administration, and surgical options are being released continuously. At Georgia Eye Partners, we strive to be at the forefront of this new technology so that our patients can benefit from what is available.


Georgia Eye Partners is a group practice of ophthalmologists and optometrists dedicated to providing our patients in Metro Atlanta and North Georgia with the highest quality medical and surgical specialty eye care. Learn more about our practice locations and book appointments online here.

Posted in: News and Updates, Patient Education

Contact Us