More than 4 years' experience with electronic intraocular needle tonometry

Background: Applanation tonometry in eyes with pathological corneae can oft en not be performed or delivers rather questionable results. We report on o ur 4-year experience with electronic intraocular needle tonometry. Patients and methods: After since 1994 developing and calibrating a system for intraocular needle tonometry, we have performed 395 measurements in 252 eyes with irregular corneae and suspicion of glaucoma. If applanation tono metry Values could be obtained, they were compared with the true intraocula r pressure. Results: Depending on the kind of corneal pathology, applanation tonometry values were lower and sometimes much lower than true intraocular pressure. No serious complications occurred as a result of intraocular needle tonomet ry. Conclusions: Intraocular needle tonometry is a safe procedure and is the on ly way to measure intraocular pressure precisely in eyes with pathological corneae.