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Updated: May 5, 2026
Using a Laminating Technique to Perform Confocal Microscopy of the Human Sclera
Published on: May 6, 2016
A Novel Schlemm's Canal Scaffold: Histologic Observations
Ian Grierson1, Hady Saheb, Malik Y Kahook
1*Department of Eye and Vision Sciences, University of Liverpool, Liverpool, UK †Department of Ophthalmology, McGill University, Montreal, QC ∥Department of Ophthalmology and Visual Sciences, University of Toronto, Mississauga, ON, Canada ‡Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO §Department of Ophthalmology, University of Washington, Seattle, WA #Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE ¶Ivantis Inc., Irvine, CA.
The Hydrus Microstent, made of nickel-titanium alloy, showed excellent biocompatibility in preclinical eye studies. This novel implant for improving aqueous humor outflow caused minimal inflammation and fibrosis in non-human primates and rabbits.
Area of Science:
- Ophthalmology
- Biomaterials Science
- Medical Device Engineering
Background:
- Glaucoma treatment often involves improving aqueous humor outflow.
- Nitinol (nickel-titanium alloy) is a potential material for intraocular implants due to its properties.
- Assessing the biocompatibility of novel medical devices is crucial before clinical application.
Purpose of the Study:
- To evaluate the biocompatibility of a novel Nitinol microstent designed to enhance aqueous humor outflow.
- To assess the long-term tissue response to the Hydrus Microstent in ocular tissues.
Main Methods:
- Biocompatibility testing in non-human primates (NHPs) and New Zealand white rabbits.
- Microstents were implanted into Schlemm's canal (SC) in NHPs and into the sclera/subconjunctival space in rabbits.
- Histological and scanning electron microscopy analysis was performed at 13 weeks (NHPs) and 26 weeks (rabbits).
Main Results:
- In NHPs, microstents in SC showed no acute/chronic inflammation, granulation, or fibrosis.
- Rabbit eyes exhibited minimal mononuclear cell infiltration and fibrosis at implant sites compared to controls.
- Both NHP and rabbit studies indicated a lack of significant adverse tissue reactions.
Conclusions:
- The Hydrus Microstent demonstrated excellent long-term biocompatibility in preclinical models.
- Minimal inflammation and fibrotic responses suggest the Nitinol microstent is well-tolerated in ocular tissues.
- These findings support the potential of the Hydrus Microstent for improving aqueous humor outflow.
