Methods applied to date

As early as 1917 Bailliart (1) increased intraocular pressure using a spring balance and was thus able to observe the optic disk using an ophthalmoscope. Sisler (2) described a procedure in 1972 using a contact lens, which was connected to a dynamometric device fixed to a slit lamp. Because intraocular pressure is changed even during examination with a contact lens, the latter can itself be used as an indentation or pressure instrument. In addition, given that direct measurement of pressure at the cornea is the most exact method of determining intraocular pressure, the optimum method of ophthalmodynamometry consists in theory of increasing intraocular pressure artificially with a contact lens and simultaneously measuring it at the contact surface of the lens. Robert (3) developed this principle with the SmartLens®. This consists of a contact lens fitted with a pressure sensor at the contact surface with the cornea. It means that ocular pulse amplitude (OPA) can be accurately determined by electronic methods. The unrestricted examination of the fundus necessary for dynamometry is, however, somewhat limited by the construction of the contact lens.

(1) Bailliart, P.: Ann. Ocul. 154, 648-666 (1917)

(2) Sisler, H.A.: optical corneal pressure ophthalmodynamometer. Am. J. Ophthalmol. 74:987, 1972

(5) Kanngiesser, H., Robert, Y., Dekker, P.: Kontaktglastonometer, In: Der Ophthalmologe, Band 93, S. 549-551, Springer Verlag, Berlin 1996