Efficacy and Safety of Hole Implantable Collamer Lens in Comparison with Original Implantable Collamer Lens in Patients with Moderate to High Myopia.

Background: Laser in situ Keratomileusis (LASIK) is the most commonly performed and widely accepted corneal refractive procedure. The Visian Implantable Collamer lens (ICL, STAAR Surgical), a posterior chamber phakic intraocular lens, has been reported to be very effective in correction of moderate to high myopia in patients who are unable to proceed with LASIK surgery due either high correction or thin cornea. A modified implantable collamer lens (ICL) with a central hole (diameter 0.36 mm), "Hole ICL", was created to improve aqueous humor circulation: not only does it make the ICL implantation feasible without prior Laser peripheral iridotomy, but it also helps to reduce the incidence of cataract formation after ICL implantation because of its resultant improvement in aqueous humor circulation behind the ICL. Objective: To evaluate the efficacy and safety of the new "Hole ICL" in comparison with conventional ICL 3 months after implantation. Material and Method: This study was a non-inferiority trial in which both ICL models, the conventional ICL (Group A) and the new Hole ICL (Group B), were studied. Patients were divided into 2 groups, each containing 60 eyes: the conventional ICL group, requiring laser peripheral iridotomy, and the new Hole ICL group. The uncorrected distance visual acuity (UDVA) log MAR and the intraocular pressure (IOP) were recorded preoperatively, and then 1 day, 1 week, 1 month and 3 months postoperatively. Spherical aberration was measured preoperatively and 3 months postoperatively. Results: The mean age in the conventional ICL group was 29.75±6.17 years (range 21-45 years), and 28.75±5.27 years (range 21-39 years) in the Hole ICL group. There was no pupillary block in either group. The UCVA log MAR in both groups showed statistically significant improvement 3 months postoperatively compared with preoperative log MAR, but there was no statistically significant difference between the log MARs of the two groups 3 months postoperatively. There was no significant change in preoperative IOP and IOP 1 day, 1 week, 1 month and 3 months postoperatively in either group, there was no difference between postoperative IOP in the two groups, and there was also no statistical significance between the spherical aberration changes in the 2 groups 3 months postoperatively. Conclusion: The two groups had similar clinical effectiveness in terms of unaided visual acuity, best corrected visual acuity, intraocular pressure and spherical aberration induction. The new Hole-ICL group (Group B) needed no preoperative laser peripheral iridotomies or intraoperative iridectomy.

Comparison of visual outcomes for aspheric and spherical toric intraocular lens implantation in cataract patients with pre-existing corneal astigmatism: a randomized control trial.

BACKGROUND: With spherical intraocular lens (IOL) implantation, unaided vision of cataract patients with pre-existing corneal astigmatism is unsatisfactory because astigmatic spectacles will always be needed for clear vision. Toric IOL has been proven to be a major improvement in cataract surgery for spectacle independence. Aspheric property, reported to improve visual quality in a non-toric IOL, has now been added to toric IOL for even better unaided vision. OBJECTIVE: To compare visual and aberrometric outcomes of 2 toric IOL, spherical and aspheric, at 3 months after implantation. MATERIAL AND METHOD: Cataract surgery was performed in cataract patients with pre-existing corneal astigmatism using 2 types of toric IOLs, a spherical toric IOL, Acrys of SN60T (Group A) and a aspheric toric IOL, Acrts of SN6AT, (Group B) as a randomized control trial. The uncorrected distance (UDVA) and corrected (CDVA) distance visual acuities, residual astigmatism, spherical equivalent (SE) and spherical aberration were evaluated 3 months after implantation. RESULTS: The present study included 44 eyes. No statistically significant difference was found in UDVA, CDVA and residual astigmatism between both groups. The UDVA of 0.1 logMAR or better was found in 78.26% in Group A and 85.71% in Group B. In Group A, 78.26% of eyes and in Group B, 76.19% had a refractive astigmatism value within 0.50 diopter at KP90 (polar value along the 90-degree meridian). The spherical equivalent (SE) was within ±0.5 diopter of emmetropia in 91.30% in Group A and in 80.95% in Group B. Group B had significantly lower spherical aberration Z (4, 0) than Group A. CONCLUSION: Both groups had similar clinical effectiveness for unaided visual acuity, aided visual acuity and astigmatism correction. Group B had significantly less spherical aberration induction when compared with Group A.

Wavefront and ocular spherical aberration after implantation of different types of aspheric intraocular lenses based on corneal spherical aberration.

BACKGROUND: To determine the ocular spherical aberration after using preoperative corneal spherical aberration guided aspheric IOL selection for cataract surgery. MATERIAL AND METHOD: Twenty-six eyes of cataract patients were scheduled for cataract surgery with aspheric IOL implantation based on preoperative corneal spherical aberration (SA) measured by Galilei corneal topography. The target postoperative total wavefront spherical aberration was zero. Three types of LOL were used in this study: TecnisZA9003 (Abbott Medical Optics Inc) with spherical aberration of -0.27 microm; Acrysof LQ SN60WF (Alcon Inc.) with spherical aberration of -0.20 microm and B&L Akreos with zero spherical aberration. Ocular spherical aberration was measured with a Wave Light machine 3 months postoperatively to demonstrate the total ocular spherical aberration. RESULTS: The preoperative mean corneal spherical aberration in the 3 groups was 0.351 +/- 0.08, 0.181 +/- 0.04, and 0.056 +/- 0.03 microns respectively. All 26 eyes of 26 patients completed the 3-month follow-up visit. Postoperative ocular spherical aberration of the 3 groups were: TecnisZA9003 (10 eyes) +0.023 +/- 0.011 microm; Acrysof IQ SN60WF (11 eyes) +0.045 +/- 0.018 microm; and B&L Akreos (5 eyes) +0.018 +/- 0.008 microm. These values were significantly lower than the predicted values in the Tecnis and Akreos groups and there was no correlation between the actual postoperative ocular spherical aberration and the predicted ocular spherical aberration in all groups. CONCLUSION: The implantation of an aspheric intraocular lens based on preoperative corneal spherical aberration is effective in reducing total ocular spherical aberration and improving visual function.