Measurement of intraocular lens decentration and tilt in vivo

Phillips, Paul; Rosskothen, Heinz; Pérez-Emmanuelli, Juan; Koester, Charles J.

doi:10.1016/s0886-3350(88)80086-5

Cited by 102 publications

(75 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Copyright: to assess IOL tilt and decentration in vivo, using either Purkinje meters [33][34][35][36][37] or Scheimpflug imaging [38,39]. To assess tilt and decentration in relation to HOAs after implantation of an aspheric IOL in patients, clinical studies were conducted [40,41] and it was shown that the limits for tilt and decentration for proper functioning of AIOLs found in laboratory studies were respected after AIOL implantation in vivo, resulting in a reduction of total SA.…”

Section: /3mentioning

confidence: 99%

Tilt and Decentration of Intraocular Lenses-a Brief Review

Sauer¹

2015

AOVS

View full text Add to dashboard Cite

Eyes need a flexible, clear and refractively suited lens to provide the retina with sharp images in far and near distance. But even given an optimal lens, the resulting image would be blurred without proper lens positioning, observable in some cases of Marfan syndrome or after ocular trauma with lens dislocation. In contrast, as seen in routine ophthalmologic slit lamp examination, healthy eyes do not suffer from coarse lens misalignment.

show abstract

Section: /3mentioning

confidence: 99%

Tilt and Decentration of Intraocular Lenses-a Brief Review

Sauer¹

2015

AOVS

View full text Add to dashboard Cite

show abstract

“…1 Some studies proposed a systematic method to measure lens tilt and dececentration based on a linear relation between the locations of the Purkinje images and rotation of the eye, tilt and decentration of the lens in patients with IOLs. 1,2 This methodology was validated and extensively used by Barry, Dunne and Kirschkamp [3][4][5] in several studies of the misalignment of the ocular components and was the basis for the instrument that we describe here. 6 An alternative to Purkinje imaging is the use of direct imaging of the anterior segment of the eye, from the anterior cornea to the posterior surface of the lens, such as achieved in Scheimpflug imaging.…”

mentioning

confidence: 99%

Intraocular lens alignment from Purkinje and Scheimpflug imaging

Rosales

Castro

Jiménez-Alfaro

et al. 2010

Clinical and Experimental Optometry

View full text Add to dashboard Cite

The improved designs of intraocular lenses (IOLs) implanted during cataract surgery demand understanding of the possible effects of lens misalignment on optical performance. In this review, we describe the implementation, set-up and validation of two methods to measure in vivo tilt and decentration of IOLs, one based on Purkinje imaging and the other on Scheimpflug imaging. The Purkinje system images the reflections of an oblique collimated light source on the anterior cornea and anterior and posterior IOL surfaces and relies on the well supported assumption of the linearity of the Purkinje images with respect to IOL tilt and decentration. Scheimpflug imaging requires geometrical distortion correction and image processing techniques to retrieve the pupillary axis, IOL axis and pupil centre from the three-dimensional anterior segment image of the eye. Validation of the techniques using a physical eye model indicates that IOL tilt is estimated within an accuracy of 0.261 degree and decentration within 0.161 mm. Measurements on patients implanted with aspheric IOLs indicate that IOL tilt and decentration tend to be mirror symmetric between left and right eyes. The average tilt was 1.54 degrees and the average decentration was 0.21 mm. Simulated aberration patterns using custom models of the patients eyes, built using anatomical data of the anterior cornea and foveal position, the IOL geometry and the measured IOL tilt and decentration predict the experimental wave aberrations measured using laser ray tracing aberrometry on the same eyes. This reveals a relatively minor contribution of IOL tilt and decentration on the higher-order aberrations of the normal pseudophakic eye.

show abstract

“…The method for estimating IOL alignment is based on that described in the previous works. [7][8][9] This method assumes a linear relationship between Purkinje-like image positions (PI, PIII, PIV) and rotation of the eye (β), tilt (α), and decentration (d):…”

Section: Oct Image Processingmentioning

confidence: 99%

“…The relative positions of PI, PIII, and PIV with respect to the pupil center are proportional to the eye rotation, IOL tilt, and IOL decentration. 7,8 Purkinje imaging has been used successfully for lens phakometry, 6,[9][10][11] and for measurements of tilt and decentration of the natural lens, 12,13 and IOLs (Refs. 1 and 14-16).…”

Section: Introductionmentioning

confidence: 99%

Intraocular lens alignment from an en face optical coherence tomography image Purkinje-like method

et al. 2014

View full text Add to dashboard Cite

Abstract. Measurement of intraocular lens (IOL) alignment implanted in patients in cataract surgery is important to understand their optical performance. We present a method to estimate tilt and decentration of IOLs based on optical coherence tomography (OCT) images. En face OCT images show Purkinje-like images that correspond to the specular reflections from the corneal and IOL surfaces. Unlike in standard Purkinjeimaging, the tomographic nature of OCT allows unequivocal association of the reflection with the corresponding surface. The locations of the Purkinje-like images are linear combinations of IOL tilt, IOL decentration, and eye rotation. The weighting coefficients depend on the individual anterior segment geometry, obtained from the same OCT datasets. The methodology was demonstrated on an artificial model eye with set amounts of lens tilt and decentration and five pseudophakic eyes. Measured tilt and decentration in the artificial eye differed by 3.7% and 0.9%, respectively, from nominal values. In patients, average IOL tilt and decentration from Purkinje were 3.30 AE 4.68 deg and 0.16 AE 0.16 mm, respectively, and differed on average by 0.5 deg and 0.09 mm, respectively, from direct measurements on distortion-corrected OCT images. Purkinje-based methodology from anterior segment en face OCT imaging provided, therefore, reliable measurements of IOL tilt and decentration.

show abstract

Measurement of intraocular lens decentration and tilt in vivo

Cited by 102 publications

References 10 publications

Tilt and Decentration of Intraocular Lenses-a Brief Review

Tilt and Decentration of Intraocular Lenses-a Brief Review

Intraocular lens alignment from Purkinje and Scheimpflug imaging

Intraocular lens alignment from an en face optical coherence tomography image Purkinje-like method

Contact Info

Product

Resources

About