We noticed you’re blocking ads

Thanks for visiting CRSToday. Our advertisers are important supporters of this site, and content cannot be accessed if ad-blocking software is activated.

In order to avoid adverse performance issues with this site, please white list https://crstoday.com in your ad blocker then refresh this page.

Need help? Click here for instructions.

Digital Supplement | Supported by Alcon Global Medical Affairs


When each of us sits with patients with primary open-angle glaucoma in the clinic, the actual data from a clinical trial are not an end in themselves, but a means to an end. We are focused on determining what course of action would be best for the individual in front of us, now and in the future. We want a plan to slow or prevent progression, but more so, we want to be able to share with patients that we are doing the best thing to help them save vision long-term. And so, while the detailed data from a clinical trial may not be part of our conversation, we nevertheless need to have confidence in what the data demonstrate and communicate these findings in ways that are meaningful to patients. The robustness of a study matters; whether the study population reflects real-world practice is important; the longevity of the data is important for a disease that patients will live with for 15 to 20 years of their lifetime; and aspects of trial coordination that assure retention over time help us gauge the veracity of the data.

In the HORIZON trial, it was demonstrated that the Hydrus Microstent (Alcon LLC; Fort Worth, TX; USA) plus cataract surgery (CS) provided greater long-term IOP- and medication-lowering efficacy compared to CS alone with no additional safety risk. The individual primary and secondary endpoints followed over the planned 5-year study period reinforced that point. And if we learned nothing else from the study, that one conclusion alone would be significant.

In Their Own Words: What Do You Take Away From the Evidence From HORIZON?

Pradeep Ramulu, MD, PhD: Everybody who has moderate or advanced disease once had mild disease. When I have a patient in front of me with mild primary openangle glaucoma, I don’t know if it will progress to moderate or severe, so why not use the device that has the 5-year pivotal data showing safety and efficacy? You could almost argue that you have an obligation to discuss Micro-Invasive Glaucoma Surgery (MIGS) options with patients who take medications for primary openangle glaucoma and a visually significant cataract if they are eligible for the surgery. If you don’t, there’s a chance that patient will hear about it from a friend or family member, and you suddenly have a dissatisfied patient.

I. Paul Singh, MD: There are a lot of factors that influence our choice of MIGS option for each patient. In my view, the data from the HORIZON trial suggest that the Hydrus Microstent plus cataract surgery is an effective, profoundly IOP-lowering option available to us, and based on that, I am comfortable using it in appropriately selected patients regardless of glaucoma stage. The safety shows no significant difference in serious adverse events compared to cataract surgery. There was very little need for interventional surgery over time and in a post-hoc analysis, fewer postoperative IOP spikes1 in these patients. If you feel comfortable and confident in this procedure and this stent, and you feel like it has the power you want, whether the IOP is mild or moderate, why not do it in either one of those populations of patients?

Brian Flowers, MD: When we sit with our patients, the options are often presented in a binary fashion. What we have learned from HORIZON and other studies forces us to rethink whether this is the case. There is mounting evidence that MIGS offers not only pressure control, but also less medication burden long-term with procedural interventions. It is difficult to know if this is based strictly on compliance or some other factors. Nevertheless, it’s becoming difficult to ignore at this point.

Yet, what the data from HORIZON suggest is that Hydrus Microstent plus CS has a meaningful impact on patients’ long-term disease course. Compared to CS alone, more patients in the Hydrus Microstent plus CS group achieved medication-free status, and fewer required an incisional secondary surgical intervention. Furthermore, among patients on one medication at the start of the study, the outcome for medication-free status was even more substantial.

Returning to how data such as those from HORIZON are useful when discussing treatment options with patients: certainly, the individual outcomes and data help guide evidence-based practices. The statistical analyses and the nuances of study design and methodology help us interpret the findings and their relatability to the real world. But when the conclusions from major clinical trials raise questions about the current status quo, we are challenged to change our thinking accordingly. Each of us has our own take on the most important thing we learned from reviewing HORIZON (see In Their Own Words…), yet we all agree that micro-invasive glaucoma surgery as a class, and the Hydrus Microstent in particular, has called on us to rethink the definition of a successful outcome. It has changed our approach to managing primary open-angle glaucoma. Because we have solid data from a well-executed trial, we can have confidence that offering patients surgical options earlier in the disease continuum compared to historical practice is viable, and we also do not have to wait and watch uncontrolled pressure because the safety profile is favorable enough to consider surgery even with controlled IOP (i.e., the context of concurrent cataract surgery).

So how do we use data from major clinical trials, and why are data important for real-world decision-making? Simply put, data help the clinician optimize the care of each individual patient based on the evidence.

I. Paul Singh, MD
  • The Eye Centers of Racine & Kenosha, Racine and Kenosha, Wisconsin
  • Member, GT Editorial Advisory Board
  • ipsingh@amazingeye.com
  • Financial disclosures: AbbVie/Allergan, Alcon, Glaukos, Nova Eye Medical, Sight Sciences
Brian Flowers, MD
  • Glaucoma specialist and managing partner, Ophthalmology Associates, Fort Worth, Texas
  • (817) 332-2020; bflowers@oafw2020.com
  • Financial disclosures: Consultant (Alcon, EyeNovia, Glaukos, Iantrek, iStar, Ivantis, Santen, Sight Sciences); Research (Alcon, Aerie Pharmaceuticals, Glaukos, iStar, Ivantis, NiCox, Santen, Sight Sciences)
Pradeep Ramulu, MD, PhD
  • Chief, Glaucoma Division, and Professor of Ophthalmology, Johns Hopkins Wilmer Eye Institute, Baltimore
  • pramulu@jhmi.edu
  • Financial disclosures: Alcon, W.L. Gore, Heru Inc., Perfuse Therapeutics, NIH, Roche, Janssen


CAUTION: Federal law restricts this device to sale by or on the order of a physician. INDICATIONS FOR USE: The Hydrus Microstent is indicated for use in conjunction with cataract surgery for the reduction of intraocular pressure (IOP) in adult patients with mild to moderate primary open-angle glaucoma (POAG). CONTRAINDICATIONS: The Hydrus Microstent is contraindicated under the following circumstances or conditions: (1) In eyes with angle closure glaucoma; and (2) In eyes with traumatic, malignant, uveitic, or neovascular glaucoma or discernible congenital anomalies of the anterior chamber (AC) angle. WARNINGS: Clear media for adequate visualization is required. Conditions such as corneal haze, corneal opacity or other conditions may inhibit gonioscopic view of the intended implant location. Gonioscopy should be performed prior to surgery to exclude congenital anomalies of the angle, peripheral anterior synechiae (PAS), angle closure, rubeosis and any other angle abnormalities that could lead to improper placement of the stent and pose a hazard. The surgeon should monitor the patient postoperatively for proper maintenance of intraocular pressure. The surgeon should periodically monitor the status of the microstent with gonioscopy to assess for the development of PAS, obstruction of the inlet, migration, or device-iris or device-cornea touch. The Hydrus Microstent is intended for implantation in conjunction with cataract surgery, which may impact corneal health. Therefore, caution is indicated in eyes with evidence of corneal compromise or with risk factors for corneal compromise following cataract surgery. Prior to implantation, patients with history of allergic reactions to nitonal, nickel or titanium should be counseled on the materials contained in the device, as well as potential for allergy/hypersensitivity to these materials. PRECAUTIONS: If excessive resistance is encountered during the insertion of the microstent at any time during the procedure, discontinue use of the device. The safety and effectiveness of use of more than a single Hydrus Microstent has not been established. The safety and effectiveness of the Hydrus Microstent has not been established as an alternative to the primary treatment of glaucoma with medications, in patients 21 years or younger, eyes with significant prior trauma, eyes with abnormal anterior segment, eyes with chronic inflammation, eyes with glaucoma associated with vascular disorders, eyes with preexisting pseudophakia, eyes with pseudoexfoliative or pigmentary glaucoma, and when implantation is without concomitant cataract surgery with IOL implantation. Please see a complete list of Precautions in the Instructions for use. ADVERSE EVENTS: The most frequently reported finding in the randomized pivotal trial was peripheral anterior synechiae (PAS), with the cumulative rate at 5 years (14.6% vs 3.7% for cataract surgery alone). Other Hydrus postoperative adverse events reported at 5 years included partial or complete device obstruction (8.4%) and device malposition (1.4%). Additionally, there were no new reports of persistent anterior uveitis (2/369, 0.5% at 2 years) from 2 to 5 years postoperative. There were no reports of explanted Hydrus implants over the 5-year follow-up. For additional adverse event information, please refer to the Instructions for Use. MRI INFORMATION: The Hydrus Microstent is MR-Conditional meaning that the device is safe for use in a specified MR environment under specified conditions.

Please see the Instructions for Use for complete product information.

© [2022] Alcon Inc 12/22 US-HDM-2300068