Relationship Between Corneal Aberrations and Contrast Sensitivity After Hyperopic Laser in Situ Keratomileusis

Abstract

In eyes after H-LASIK, the changes in scotopic CS significantly correlated with those in the corneal aberrations, which might have resulted from decentration or ablation profiles in H-LASIK and a relatively small optical zone. Further studies will be needed to validate this relationship.

Effect of a yellow intraocular lens on scotopic vision, glare disability, and blue color perception

“…The term scotopic is used for contrast sensitivities measured under luminances of 1 foot-lambert (3.42 cd/m 2 ) 33 and 0.09 cd/m 2,34 or illuminances of 21 lux 35 and 2 to 3 lux. 36 Rosen 37 advises using mesopic for illuminance values between 0.05 lux and 50 lux and scotopic for illuminance values less than 0.05 lux. Although the device used to measure scotopic contrast sensitivity in our study is called the Mesotest (derived from the word mesopic), it has a very low luminance (0.032 G 0.003 cd/m 2 ) and illuminance (under 0.05 lux) level to test the contrast sensitivity in the range of scotopic night conditions.…”

Correlation of higher-order wavefront aberrations with visual function in pseudophakic eyes

“…Several studies showed that the higher-order aberration in eyes with this aspherical IOL was less than that in eyes with the standard spherical IOL, and that this lesser aberration led to better contrast sensitivity, particularly under mesopic conditions. [25][26][27][28] However, although many studies have shown that the higher-order aberration is correlated significantly with contrast sensitivity after corneal refractive surgery, [22][23][24] to our knowledge, no study has shown a statistically significant correlation between higher-order aberration and visual function in eyes with a standard spherical IOL. Our study has now clarified that a significant association between higher-order aberration and visual function after cataract surgery does exist.…”

“…[14][15][16][17][18][19][20][21] Furthermore, some studies demonstrated that the ocular or corneal aberration is correlated significantly with contrast sensitivity after corneal refractive surgery. [22][23][24] Although some studies showed that contrast sensitivity in eyes with an aspherical IOL is better than that in eyes with a spherical IOL, [25][26][27][28][29] to our knowledge, there has been no study to show the statistical association of higher-order aberrations with visual functions in eyes with a standard spherical IOL.…”

Is conductive keratoplasty the treatment of choice for presbyopia?

“…Reduced contrast sensitivity at higher spatial frequencies or reduced stereoacuity were not seen with CK in a multicenter presbyopia clinical trial (discussed later in this article). Additional safety concerns regarding monovision LASIK include those associated with LASIK surgery, such as the risks of flap creation and management, severing of corneal nerves that causes dry eye, healing problems and the possibility of diffuse lamellar keratitis [30][31][32][33][34][35][36][37].…”

“…Some of these excimer laser modalities have been applied in a monovision fashion for corneal steepening in the treatment of presbyopia [26][27][28][29]. The LASEK procedure may avoid some of the potential complications of LASIK, which are mostly related to the flap, such as striae, displacements, button-hole flaps and diffuse lamellar keratitis [30][31][32][33][34][35][36][37], but the procedure is not widely performed at this time.…”