A tonometer system for measuring intraocular pressure by accurately
providing a predetermined amount of applanation to the cornea and
detecting the amount of force required to achieve the predetermined amount
of applanation. The system is also capable of measuring intraocular
pressure by indenting the cornea using a predetermined force applied using
an indenting element and detecting the distance the indenting element
moves into the cornea when the predetermined force is applied, the
distance being inversely proportional to intraocular pressure. Also
provided is a method of using the tonometer system to measure hydrodynamic
characteristics of the eye, especially outflow facility. The tonometer
system includes a contact device for placement in contact with the cornea
and an actuation apparatus for actuating the contact device so that a
portion thereof projects inwardly against the cornea to provide a
predetermined amount of applanation. The system further includes a
detecting arrangement for detecting when the predetermined amount of
applanation has been achieved and a calculation unit responsive to the
detecting arrangement for determining intraocular pressure based on the
amount of force the contact device must apply against the cornea in order
to achieve the predetermined amount of applanation. An indentation
distance detection arrangement is also provided for use when intraocular
pressure is to be detected by indentation. In carrying out the method, the
system is used to detect intraocular pressure between successive steps of
forcing intraocular fluid out from the eye.
