Automated Applanation Tonometry - Updated
Status: Recruiting
Location: See location...
Intervention Type: Device
Study Type: Interventional
Study Phase: Not Applicable
SUMMARY
Goldmann Applanation Tonometry (GAT) is considered the clinical gold standard for eye pressure measurements and yet it is known to be a subjective measurement with limited repeatability and limited portability. Another clinical standard for checking eye pressure is known as the pneumotonometer. This method is more objective but not portable. The purpose of this study is to develop new methods of measuring eye pressure that are more objective, reproducible and portable. In this study, the investigators will be comparing the eye pressure measurements using 2 investigational methods to GAT and pneuumotonometer.
Eligibility
Participation Requirements
Sex: All
Minimum Age: 18
Healthy Volunteers: f
View:
• Presenting for a routine eye exam
• ≥ 18 years of age
• Able and willing to give consent
Locations
United States
North Carolina
Duke Eye Center
RECRUITING
Durham
Contact Information
Primary
Sarah Jones
sarah.jones1@duke.edu
919 681 6584
Time Frame
Start Date: 2026-03-02
Estimated Completion Date: 2026-12-29
Participants
Target number of participants: 200
Treatments
Active_comparator: Standard GAT
This is the gold-standard method for IOP measurement in clinical practice
Experimental: Fixed-force GAT
From the patient perspective, this method will feel identical to the standard GAT. The eye is given topical fluorescein/anesthetic. The GAT dial is set at 1.8 or 2.0, a C-MOS camera is connected to one of the oculars of the slit lamp machine and under blue light illumination, the GAT prism contacts the eye while the CMOS camera makes a video of the mire appearance through the ocular. The diameters of the recorded mire images are measured and the IOP is calculated based on the mire diameter
Experimental: Upright applanating prototype
With this prototype, an applanating prism (custom manufactured with medical grade acrylic in an ISO-13485 certified facility) is attached to a fixed-force spring that creates a force equivalent to 1.8 or 2.0 on the GAT dial. Blue LED lights on the prototype are used to create the blue illumination similar to the blue light used in clinical practice on the slit lamp or Perkins tonometer. A C-MOS camera is aligned with the GAT prism to image the applanation mires. The eye is given topical fluorescein/anesthetic. Like fixed-force GAT, the GAT prism contacts the eye while the CMOS camera makes a video of the mire appearance. The diameters of the recorded mire images are measured and the IOP is calculated based on the mire diameter
Active_comparator: Pneumotonometer
This is another standard method for IOP measurement in clinical practice
Related Therapeutic Areas
Sponsors
Leads: Duke University