Examination of accommodation in pseudophakic eyes

Abstract

Some patient with monofocal intraocular lens can achieve good near visual acuity with distance correction after cataract surgery. Understanding and measuring this phenomenon also called pseudoaccommodation can help to develop new technology to substitute or restore accommodation in pseudophakic eyes. I. To measure accommodation after cataract surgery. II. To measure anterior chamber depth with Scheimpflug imaging and comparing results with standard, ultrasonic data. III. To compare anterior chamber depth data, repeatability, reproducibility and reliability with a new optical device, the anterior segment optical coherent tomography (Visante OCT) and immersion ultrasound method in phakic eyes. I. We observed accommodation with defocusing technique, partial coherent interferometry method and measuring anterior chamber depth changing during ciliary muscle blocking. II. We measured anterior chamber depth with Pentacam and data were compared to standard ultrasonic method in phakic and pseudophakic eyes. III. We analyzed anterior chamber depth data, repeatability, reproducibility and reliability obtained by two observers using Visante OCT. I. A total accommodation amplitude of 0,83 D was observed with defocusing technique. Intraocular lens movement were negligible measured by partial coherent interferometry method using physiological accommodation stimulus. Mean movement of intraocular lens was 0.18 mm during blocking of the ciliary muscle. II. Pentacam and ultrasonic device measure the same anterior chamber depth in phakic eyes, but in pseudophakic eyes optical method measures significantly shallower anterior chamber depth. III. Anterior segment optical coherent tomography measures deeper anterior chamber depth than immersion ultrasonic device in phakic eyes. Accomodation and pseudoaccommodation observed in pseudophakic eyes is hard to measure and only parts of this process can be measured with each technique. Anterior chamber depth data varies by the measuring technique. Repeatability, reproducibility and reliability of anterior chamber depth data were better with optical technique.