title: New method for remote and repeatable monitoring of intraocular pressure variations.
abstract: We present initial steps toward a new measurement device enabling high-precision, noncontact remote and repeatable monitoring of intraocular pressure (IOP)-based on an innovative measurement principle. Using only a camera and a laser source, the device measures IOP by tracking the secondary speckle pattern trajectories produced by the reflection of an illuminating laser beam from the iris or the sclera. The device was tested on rabbit eyes using two different methods to modify IOP: via an infusion bag and via mechanical pressure. In both cases, the eyes were stimulated with increasing and decreasing ramps of the IOP. As IOP variations changed the speckle distributions reflected back from the eye, data were recorded under various optical configurations to define and optimize the best experimental configuration for the IOP extraction. The association between the data provided by our proposed device and that resulting from controlled modification of the IOP was assessed, revealing high correlation (R2=0.98) and sensitivity and providing a high-precision measurement (5% estimated error) for the best experimental configuration. Future steps will be directed toward applying the proposed measurement principle in clinical trials for monitoring IOP with human subjects.
authors: Bar-Ilan University, Faculty of Engineering, Ramat-Gan 52900, Israel.
authors: Israel
authors: I
authors: Margalit
authors: Bar-Ilan University, Faculty of Engineering, Ramat-Gan 52900, Israel.
authors: Yevgeny
authors: Y
authors: Beiderman
authors: Tel-Aviv University, Goldshleger Eye Research Institute, Tel-Hashomer 52621, Israel.
authors: Alon
authors: A
authors: Skaat
authors: Tel-Aviv University, Goldshleger Eye Research Institute, Tel-Hashomer 52621, Israel.
authors: Elkanah
authors: E
authors: Rosenfeld
authors: Tel-Aviv University, Goldshleger Eye Research Institute, Tel-Hashomer 52621, Israel.
authors: Michael
authors: M
authors: Belkin
authors: Augenklini, Schwabachanlage 6, 91054 Erlangen, Germany.
authors: Ralf-Peter
authors: RP
authors: Tornow
authors: Universitat de València, Facultat de Física, Departamento de Óptica, C/Doctor Moliner 50, 46100 Burjassot, Spain.
authors: Vicente
authors: V
authors: Mico
authors: Universitat de València, Facultat de Física, Departamento de Óptica, C/Doctor Moliner 50, 46100 Burjassot, Spain.
authors: Javier
authors: J
authors: Garcia
authors: Bar-Ilan University, Faculty of Engineering, Ramat-Gan 52900, Israel.
authors: Zeev
authors: Z
authors: Zalevsky
mesh_terms: D000818:Animals; D003941:Diagnostic Techniques, Ophthalmological; D007429:Intraocular Pressure / Q000502:physiology*; D008991:Monitoring, Physiologic / Q000379:methods*; D011817:Rabbits; D058998:Remote Sensing Technology / Q000379:methods*; D015203:Reproducibility of Results