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Purpose: To objectively analyze the optical quality of the FineVision Toric intraocular lens (IOL) with two cylinder powers when different combinations of rotations and residual refractive errors are induced., Methods: This study assessed the FineVision Toric IOL with two different cylinder powers: 1.5 and 3.0 diopters (D). Three different rotation positions were considered: centered, 5° and 10° rotated. An optical bench (PMTF) was used for optical analysis. The optical quality of the IOLs was calculated by the modulation transfer function (MTF) at five different focal points (0.0, 0.25, 0.50, 0.75, and 1.00 D)., Results: The MTF averaged value of the reference situation was 38.58 and 37.74 for 1.5 and 3.0 D of cylinder, respectively. For the 1.5 D cylinder, the combination of 5° of rotation with a defocus of 0.25, 0.50, 0.75, and 1.0 D induced a decrease on the MTF of 12.39, 19.94, 23.43, 24.23 units, respectively. When induced rotation was 10°, the MTF decrease was 17.26, 23.40, 24.33, 24.48 units, respectively. For the 3.0 D cylinder, the combination of 5° with 0.25, 0.50, 0.75, and 1.0 D of defocus, induced a decrease on the MTF of 12.51, 18.97, 22.36, 22.48 units, respectively. When induced rotation was 10°, the MTF decrease was: 18.42, 21.57, 23.08, and 23.61 units, respectively., Conclusion: For both FineVision Toric IOLs there is a certain optical tolerance to rotations up to 5° or residual refractive errors up to 0.25 D. Situations over these limits and their combination would affect the visual quality of patients implanted with these trifocal toric IOLs.

Purpose: To evaluate the outcomes of implanting intrastromal corneal ring segment (ICRS) using two different strategies in a specific paracentral keratoconus phenotype., Methods: Eighty-nine eyes with paracentral keratoconus with perpendicular topographic astigmatism and comatic axes were evaluated before and after implanting a 150° arc-length ICRS. Patients were divided into two groups according to the axis where the ICRS was implanted: Group I: comatic axis and Group II: flat topographic axis. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refractive errors, and root mean square (RMS) for coma-like aberration were recorded. The postoperative follow-up was 1 year., Results: Mean UDVA (logMAR) changed from 0.49 ± 0.37 preoperatively to 0.30 ± 0.32 6 months afterwards ( p  < 0.001) in the group I and from 0.53 ± 0.34 to 0.37 ± 0.35 ( p  < 0.001), in the group II. Mean CDVA in group I changed from 0.11 ± 0.18 preoperatively to 0.06 ± 0.14 6 months after surgery ( p  < 0.001). In group II the improvement did not reach statistical significance (from 0.09 ± 0.10 to 0.07 ± 0.09; p  = 0.06). No eyes lost lines of CDVA in group I. Eight eyes (15.7%) lost lines of CDVA in group II. The spherical equivalent decreased after surgery in both groups ( p  < 0.001). The RMS for corneal coma-like aberration only decreased in the group I ( p  < 0.001)., Conclusion: Both strategies provided safe and effective visual and refractive outcomes in the specific keratoconus phenotype analyzed. The orthopedic strategy provided better visual outcomes than the refractive one.

Background: The aim was to assess the impact of 5- and 10-degree rotations in the optical quality of a trifocal toric intraocular lens with different amounts of cylinder., Methods: Two Physiol Toric intraocular lenses with 1.5 and 3.0 D of cylinder were analysed in three different positions: centred, 5 and 10 degrees rotated. The optical quality of the intraocular lenses was evaluated with the PMTF optical bench through specific perpendicular targets. The analysis was performed by the through-focus modulation transfer function curves and the modulation transfer function corresponding to distance vision (0 D of vergence)., Results: For a centred situation, the through-focus modulation transfer function curves of both intraocular lenses showed the classical three peaks corresponding to the powers of the two principal meridians of the intraocular lenses. When 5 and 10 degrees of rotation were induced, the three peaks were attenuated in both cases. The case with the intraocular lens with 3.0 D of cylinder and 10 degrees of rotation showed the worst optical quality and a significant loss of trifocality. The modulation transfer function values obtained for distance vision also showed the worst optical quality for the intraocular lens with 3.0 D of cylinder and 10 degrees of rotation., Conclusion: Rotations over 5 degrees decreased the optical quality of trifocal toric intraocular lenses, being this reduction moderate from 5 to 10 degrees for low levels of cylinder (≤1.5 D). For mid-high levels of cylinder (≥3.0 D), rotations over 5 degrees cause a significant loss of optical quality at all object distances.

Purpose: The purpose was to compare the visual, refractive and aberrometric results of intrastromal corneal ring segments implantation with manual dissection and femtosecond laser-assisted surgery., Methods: This is a multicentre study, which included consecutive patients with paracentral keratoconus, in which the difference between the axes of the topographic flattest and the coma aberration was <60°, who had Ferrara-type intrastromal corneal ring segment implantation using manual dissection or femtosecond laser technique. LogMAR uncorrected (uncorrected distance visual acuity) and corrected (corrected distance visual acuity) distance visual acuity, refractive errors and the root mean square for corneal coma-like aberration were recorded before and at 6 months after surgery., Results: The study included 84 and 110 eyes in the manual group and in the femtosecond group, respectively. After surgery, there was a statistically significant improvement in uncorrected distance visual acuity and corrected distance visual acuity for both groups ( p  < 0.0001), and there were no statistically significant differences between groups ( p  > 0.3). For both groups, there was a reduction in spherical equivalent after intrastromal corneal ring segment implantation ( p  < 0.0001). There were no statistically significant differences between groups in the magnitude of spherical equivalent reduction ( p  = 0.34) The magnitude of the root mean square coma-like reduction was 0.93 ± 0.76 and 0.83 ± 0.80 μm in the manual and femtosecond group, respectively ( p  = 0.2). While in the femtosecond laser group no complications were reported, in the manual group, the intraoperative or postoperative complications rate was 13.09%., Conclusion: Although both surgical techniques provide comparable visual, refractive and aberrometric outcomes, it should be noted that the femtosecond laser is a safer surgical procedure, with no complications reported.

Purpose: To assess the outcomes of implanting Ferrara-type intrastromal corneal ring segments in central 'bow-tie'-shaped keratoconus over 3 years of follow-up., Methods: A total of 20 eyes with central 'bow-tie'-shaped keratoconus were evaluated before and after implanting Ferrara-type intrastromal corneal ring segments (AJL Ophthalmic, Spain). LogMAR uncorrected distance visual acuity and best corrected distance visual acuity and residual refractive errors analysed using vector analysis were recorded preoperatively, at 6 months, 1 year, and 3 years postoperatively., Results: The mean uncorrected distance visual acuity (LogMAR scale) rose from a preoperative 0.75 ± 0.28 to a 6-month postoperative 0.38 ± 0.28 (p < 0.0001). The corrected distance visual acuity, in turn, improved from 0.07 ± 0.06 to 0.05 ± 0.06 (p = 0.0008). Both the uncorrected distance visual acuity and corrected distance visual acuity were stable over the postoperative period in both groups (p > 0.05). None of the eyes lost uncorrected distance visual acuity and corrected distance visual acuity lines over the postoperative follow-up period. The spherical equivalent and the refractive cylinder declined steeply after intrastromal corneal ring segments implantation (p < 0.0001). Both the spherical equivalent and refractive cylinder were stable over the postoperative period. None of the eyes had an increase in maximum or minimum keratometry greater than 0.75D over the postoperative period., Conclusion: The planning for intrastromal corneal ring segments insertion proposed in this study reduces the spherical equivalent and refractive cylinder in this type of keratoconus, while improving post-surgery uncorrected distance visual acuity and corrected distance visual acuity. These results remain stable over 3 years of follow-up. Therefore, this procedure could be considered as an effective therapeutic alternative in patients affected by this type of keratoconus.

Purpose: To asses visual quality after bilateral implantation of the Acri.LISA 366D intraocular lens (IOL) (Carl Zeiss Meditec) in patients with high and low-moderate myopia., Methods: A total of 304 eyes of 152 patients had bilateral implantation of the Acri.LISA 366D IOL. The patients were divided into 2 groups: low-moderate myopia (IOL power from 15 to 20.5 D) and high myopia (IOL power from 0 to 14.5 D). Monocular and binocular best-corrected distance visual acuity (BCVA) and best distance-corrected near visual acuity (BCNVA), binocular best distance-corrected intermediate visual acuity (BCIVA), and distance contrast sensitivity (CS) under photopic (85 cd/m2) and mesopic (5 cd/m2) conditions were determined., Results: At the 6-month postoperative visit, there were no statistically significant differences in monocular and binocular BCVA (p=0.13 and p=0.22, respectively). Monocular and binocular BCNVA was comparable between the groups (p=0.26 and p=0.09, respectively). The mean binocular BCIVA changed significantly as a function of the distance of the test (p<0.01) in both groups, and there were no statistically significant differences between groups at any distance. Monocular and binocular CS under photopic and mesopic conditions was similar between both groups (p>0.01)., Conclusions: Bilateral implantation of the Acri.LISA 366D in high myopic eyes provides a satisfactory full range of vision comparable to that obtained in low-moderate myopic eyes.