Analysis of pupil and corneal wave aberration data supplied by the SN CT 1000 topography system

Comastri, Silvia A.; Martín, Gabriel; Pförtner, Timo-Kolja

doi:10.1016/j.ijleo.2005.11.018

Cited by 6 publications

(5 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Higher order aberrations are often affected by pupil size. When performing measurements for laboratory use, the iris sphincter and ciliary muscle are often paralysed using cycloplegics, to inactivate pupillary oscillations and accommodation 9 to ensure the validity of measurements.…”

Section: Ocular Aberrationsmentioning

confidence: 99%

Ocular aberrations and wavefront aberrometry: A review

Unterhorst

Rubin

2015

African Vision and Eye Health

View full text Add to dashboard Cite

Wavefront aberrations can be described as deviations of the wavefront exiting the eye froma reference wavefront that is aberration free and diffraction limited. Ocular aberrations canbe sub-categorised as lower and higher order aberrations. Ocular aberrations have promptedinterest amongst the ocular healthcare community owing to their influences on the visualfunctioning of patients as well as differences observed in ocular aberrations through the useof refractive surgery both pre- and post-operatively. Uncompensated refractive error remainsone of the most common reasons for which patients consult optometrists. Compensationof refractive error, or lower order aberrations, has become a routine procedure during anoptometric examination. However, there are some patients who experience visual symptomseven after their refractive errors have been compensated via spectacles or contact lenses.Higher-order aberrations may be the source of these visual disturbances. Refractive surgeryhas been found to influence and even induce various changes in higher-order aberrationspost-operatively, which in turn has led to increased interest in wavefront aberrations and howthe measurement of these aberrations can improve diagnosis and treatment within optometryand ophthalmology.

show abstract

Section: Ocular Aberrationsmentioning

confidence: 99%

Ocular aberrations and wavefront aberrometry: A review

Unterhorst

Rubin

2015

African Vision and Eye Health

View full text Add to dashboard Cite

show abstract

“…Since E r,g depends on d S (Fig. 6), if the sensor is the eye, these percentages vary because pupil diameter depends on the subject and, under natural conditions, it is usually less than 10 mm [8,16]. For example if d S ¼ 4 mm, the effects of lateral shifts and reflections modify in 15% the relative illuminance, which would be obtained only considering the effect of pupil size variation introduced by a 6 dioptres lens and we have e % ¼ À18% for a À6 dioptres lens and e % ¼ 39% for a 6 dioptres one.…”

Section: Total Relative Illuminancementioning

confidence: 99%

Influence of ophthalmic lenses in the illuminance originated at a peripheral glare source and reaching the eye

Comastri

Matranga

Bastida

et al. 2009

Optik

View full text Add to dashboard Cite

“…In addition, in young, healthy eyes, corneal aberrations are almost totally compensated for by the internal aberrations of the eye. 10,11,12,13 Instruments such as the KR-1W Wavefront Aberrometer are available these days that will allow both corneal and internal aberrations to be determined relatively easily and effectively and these measurements can have clinical and other diagnostic benefits. 14 With age, fourth-order aberrations in a population were shown to increase and mostly be positive and notably different from zero.…”

Section: Introductionmentioning

confidence: 99%

“…15 Both LOA and HOA are utilised in the advancement of the design of ophthalmic, contact and IOL as well as other lenses such as those used in cameras. 11 To use a spectacle lens to reduce SA, the lens would have to have a specific pantoscopic tilt, facial wrap and vertex distance, which is usually difficult to achieve. 12 Simple spherical refractive errors (related to the LOA of defocus) have been corrected by spherical lenses from as early as the 17th century.…”

Section: Introductionmentioning

confidence: 99%

A review of higher order aberrations of the human eye

Suliman

Rubin

2019

African Vision and Eye Health

View full text Add to dashboard Cite

Background: This literature review is part of a research study for aberration-correcting soft contact lenses, where wavefront aberrometry was utilised.Aim: This study was conducted as part of a postgraduate research degree by the first author with particular relevance to spherical aberrations in relation to myopia and soft contact lenses, both aberration control and non-control types.Setting: This study reports on a literature review of higher order aberrations.Methods: A comprehensive review of various databases was performed, including PubMed and Google Scholar in terms of aberration control contact lenses and particular customised contact lenses for compensation of spherical aberration in myopia, was performed.Results: Wavefront sensing and Zernike polynomials are increasingly used in optometry and ophthalmology to quantify the wavefronts for an optical system such as the eye, using either lower order (LOA) or higher order aberrations (HOA). Although other mathematical methods are available, zero, 1st and 2nd orders of the Zernike polynomial expansion are LOA. Defocus ( 2 0 Z ) and astigmatism ( − and 2 2 2 2 Z Z ) are 2nd-order modes that usually can be corrected by clinicians using ordinary sphero-cylindrical compensations such as spectacle lenses. Until recently, only LOA were easily correctable by clinicians in optometry and ophthalmology. Higher order aberrations are those modes in the third radial order, n = 3 and higher, which in the past were not correctable. However, HOA contribute to only about 7% of retinal image quality and often go unnoticed by individuals, although in some instances, for example, with keratoconus or after refractive surgery, such aberrations can become more problematic. Today, new treatments are available via specially designed or customised (to an individual) rigid or soft contact lenses that are claimed to reduce or eliminate HOA such as spherical aberration ( 4 0 Z ). Conclusion:Although such specially designed or customised contact lenses have some effect on HOA, there are conflicting reports and so further investigation of this intriguing aspect remains necessary.

show abstract

Analysis of pupil and corneal wave aberration data supplied by the SN CT 1000 topography system

Cited by 6 publications

References 19 publications

Ocular aberrations and wavefront aberrometry: A review

Ocular aberrations and wavefront aberrometry: A review

Influence of ophthalmic lenses in the illuminance originated at a peripheral glare source and reaching the eye

A review of higher order aberrations of the human eye

Contact Info

Product

Resources

About