Intraocular Pressure Accuracy and Variability of the Barraquer Tonometer

Study to Compare the Accuracy and Variability of the Barraquer Tonometer With Other Methods of Tonometry

To determine if the Barraquer tonometer provides an accurate and reliable measurement of intraocular pressure. The Barraquer tonometer is a device used to safely and painlessly measure intraocular pressure.

Intraocular pressure will be checked using four different methods of tonometry. These four methods will include Tonopen, Goldmann applanation tonometry, Schiotz tonometry, and Barraquer tonometer. The data will then be compared to determine the reliability and accuracy of the Barraquer tonometer.

Inclusion Criteria:

1. All patients of Barnes Retina Institute who are scheduled to undergo vitreoretinal surgery.
2. All patients scheduled for routine eye examination at the Washington University Eye Clinic or Barnes Jewish Eye Clinic.
3. All ages (patients seen at these locations are adult patients >18 years of age).

Exclusion Criteria:

1. Any patient who is seen in the outpatient clinics for an urgent or emergency ophthalmological issue.
2. Any patient who has a contraindication to routine, noninvasive methods of tonometry and/or pachymetry (ie corneal ulcer).