The ORA G3 from Reichert measures corneal hysteresis, a predictor of glaucoma progression.

The Ocular Response Analyzer G3 from Reichert takes glaucoma risk assessment to the next level.

Corneal hysteresis is one of the significant new diagnostic elements in the care of glaucoma patients, and research has found that its measurements can better identify the risk of glaucoma progression. The Ocular Response Analyzer (ORA) G3 is the third-generation of the tonometer which measures corneal hysteresis.  Here’s how it helps predict glaucoma earlier.

Corneal hysteresis is the difference between the bidirectional applanation signal of initial pressure required to produce flattening of the cornea and the subsequent out peak signal, which takes place once the cornea has been over-flattened to a concave position. The difference between the two is a unique biomechanical signature of the cornea, which allows the clinician to interpret glaucomatous risk.  Lower corneal hysteresis measurements can mean faster rates of visual field loss””even if the patient has a low IOP.

Once I started using the ORA G3 on a consistent basis, it quickly became clear that corneal hysteresis values were extremely important in both the decision to initiate treatment in patients who were borderline and/or highly suspicious and then subsequently in the long-term management of the existing glaucoma patient base relative to individuals at higher risk and the potential for progression.

The device also provides IOP measurements that compare extremely well with standard Goldmann IOPs (IOPg). Additionally, it measures corneal compensated IOP (IOPcc), which is less influenced by corneal properties.

Another advantage of this technology is that technicians can perform basic IOP assessment while the clinician is engaged in more significant aspects of the patient interface. This aspect of the use of the ORA G3 required a period of time to become comfortable. However, after performing over a thousand measurements comparing the IOPcc to IOPg measurements to assure consistency of outcomes, it became evident that the data developed by the ORA G3 replicated that of traditional Goldmann at an extremely high level. As a result I have implemented the technology as my standard system for IOP assessment and use the corneal hysteresis as an initial consideration in the diagnosis and treatment of the glaucoma patient.

The ORA G3 has proven to be an invaluable resource and has shown itself to be extremely accurate, efficient and time-saving in the day-to-day management of my glaucoma patient base.

J. James Thimons, OD, FAAO, is in private practice in Fairfield, CT, and chairman of the National Glaucoma Society.

Comments From the Docs:
“The ORA G3 is truly an instrument for the third millennium eyecare office. It provides a technician-friendly cross-contamination-free method of obtaining reliable IOP measurement for all of our patients that is independent of central corneal thickness and corneal properties. In addition, unlike other tonometers, corneal hysteresis is eligible for insurance reimbursement with CPT Code 92145.”
““Elliot M. Kirstein, OD, FAAO,
Cincinnati, OH

“The ORA G3 has made a positive impact on our practice. Corneal hysteresis measure gives us one more objective piece of the puzzle, to help predict glaucoma progression””or hopefully lack of progression”
““Joseph E. Pavano III, OD,
New Britain, CT


Reichert Technologies
716.686.4500 |


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