Determination of the tonographic effect in the human eye using a pneumatic pressure modulator

Abstract Purpose The tonographic effect has been observed in several studies in occulopression, repeated tonometry or ophthalmodynamometry. It describes an intraocular pressure (IOP) decrease caused by an artifical IOP increase. In healthy eyes, an IOP drop of 2–3 mmHg/min was reported. However, there are studies that show a reduced decrease of the IOP drop for instance in glaucoma patients. In this work, we present a proof of principle to determine the tonographic effect in healthy eyes by utilizing a novel pneumatic pressure modulator. Methods The study was conducted on 8 healthy subjects (4 m, 4 f, 1 eye each, mean age 27.4 ± 7.1 yr). All subjects passed an ophthalmic examination procedure, including visual acuity determination, tonometry, objective refraction, slit lamp examination. Exclusion criteria were myopia