Influence of Angle κ and Higher-Order Aberrations on Visual Quality Employing Two Diffractive Trifocal IOLs

Abstract

Prospective, randomized, comparative, and controlled study to estimate the association between angle κ distance and higher-order aberrations (HOAs) with postoperative visual acuity after presbyopia-correcting IOL implantation. Forty-three eyes from 43 patients were included and randomly assigned in two groups for either AT LISA tri 839MP or Acrysof IQ PanOptix IOL implantation. The OPD-Scan III analyzer was utilized to assess the angle κ distance and higher-order aberration (HOAs). Twenty-three eyes were in the Acrysof IQ PanOptix group and 20 patients in the AT LISA tri 839MP group. The uncorrected distance visual acuity (UDVA) for the PanOptix group was 0.092 ± 0.10, whereas for AT LISA tri was 0.050 ± 0.06 (P=0.229). The uncorrected intermediate visual acuity (UIVA) for the PanOptix group was 0.173 ± 0.18, whereas for AT LISA tri, it was 0.182 ± 0.11 (P=0.669). Uncorrected near visual acuity (UNVA) was 0.068 ± 0.04 and 0.085 ± 0.07, respectively (P=0.221). Also, correlation coefficient between HOAs and the Strehl ratio for each group were −0.768 (P < 0.0001) and −0.863 (P=0.0001). Patients implanted with both trifocal IOLs showed excellent postoperative visual performance at all distances at the six-month follow-up visit. No association was found between angle κ distance and postoperative visual acuity regardless of the angle κ magnitude or the two trifocal IOLs inner optical diameter. Also, internal aberrations demonstrated a significant inverse correlation with the Strehl ratio for both trifocal IOLs.

The Effects of Angle Kappa on Clinical Results and Patient-Reported Outcomes After Implantation of a Trifocal Intraocular Lens

“… 10–13 As shown in Table 2 , the manifest refraction and visual acuity were not statistically significantly different by AK group. These findings appear to corroborate the results reported by Garzón et al 8 and Velasco-Barona et al, 9 though the first study related to a different trifocal IOL. The refractive and acuity results also appear consistent with the results from Qi et al, 7 where visual disturbances, but not refraction and acuity, appeared related to higher AK values.…”

“… 7 Other studies involving trifocal IOLs found no correlations between angle kappa and any measures of vision or visual quality. 8 , 9 …”

Impact of correlation of angle α with ocular biometry variables

“…Therefore, if a diffractive mIOL is decentered from the visual axis, it could result in decreased vision, inducing higher-order aberrations and photic phenomena, including reduced contrast sensitivity, glare, and halos. [6][7][8][9] In addition, the lens tends to allocate on the center of the capsular bag, which is more closely related to the center of the limbus. Therefore, it is necessary to know in advance whether the visual axis and the center of the WTW diameter of the patient are misaligned.…”

The relationship between angle kappa and astigmatism after phacoemulsification with implanting of spherical and aspheric intraocular lens

“…Corneal topographic systems have been used to evaluate K . [ 2 35 36 37 ] Topographers estimate K by measuring the distance between the pupil centre and the first Purkinje image of an axial target (the bright corneal reflex) when the eye is in the primary position of gaze. It is assumed that the intercept (a) between the visual axis and the anterior corneal surface coincides with the location of this bright corneal reflex and (b) of the pupillary axis striking the anterior corneal surface coincides with the pupil center.…”