Effect of Co-Implantation of a Capsular Tension Ring on Clinical Outcomes after Cataract Surgery with Monofocal Intraocular Lens Implantation

PURPOSE: The objective was to evaluate the effect of co-implantation of a preloaded capsular tension ring (CTR) and aberration-free monofocal intraocular lens (IOL) on clinical outcomes and visual quality after cataract surgery. MATERIALS AND METHODS: Patients who underwent cataract surgery were randomized into two groups that were implanted with a CTR and IOL (group 1, 26 eyes) or an IOL only (group 2, 26 eyes). At 1 and 3 months after surgery, visual acuity, refractive errors, refractive prediction errors, ocular aberrations, and modulation transfer function (MTF) were analyzed. At 3 months postoperatively, anterior chamber depth (ACD) and contrast sensitivity were evaluated. RESULTS: Group 1 showed greater hyperopic shift, which caused the refractive prediction error at 3 months after surgery to be significantly different between the two groups (p=0.049). Differences in ACD between the preoperative and postoperative periods tended to be greater in group 1 than in group 2. At 3 months postoperatively, internal MTF values at 20, 25, and 30 cycles per degree were significantly better in group 1 than in group 2 (p=0.034, 0.017, and 0.017, respectively). Contrast sensitivity showed comparable results at almost all spatial frequencies between the groups. CONCLUSION: Regarding visual acuity and quality, both groups showed comparable results. Co-implantation of a CTR and aberration-free monofocal IOL was associated with hyperopic refractive outcomes. Surgeons should consider the position of the IOL when planning co-implantation of a CTR and IOL.

Wavefront Analysis of Successful Treatment of Monocular Triplopia After Cataract Extraction: Report of 2 Cases

PURPOSE: To report wavefront analysis of successful treatment of monocular triplopia after cataract extraction. CASE SUMMARY: (Case 1) A 59-year-old man visited our clinic for a monocular triplopia in his left eye of five years in duration. The best spectacle-corrected visual acuity (BSCVA) was 1.0 in the left eye, and the patient had a mild cortical cataract. The ocular spherical aberration (0.126 micrometer for the 4-mm pupil, 0.351 micrometer for the 6-mm pupil) measured by a Hartmann-Shack aberrometer increased preoperatively, while the corneal spherical aberration was normal. After cataract surgery, the monocular triplopia disappeared, and the ocular spherical aberration decreased. (Case 2) A 38-year-old man visited our clinic for a monocular triplopia in his left eye of a two-year duration. The best spectacle-corrected visual acuity (BSCVA) was 0.3 in the left eye, and the patient had a mild nuclear cataract. The ocular spherical aberration (-0.356 micrometer, -1.343 micrometer) and trefoil aberration (0.199 micrometer, 0.252 micrometer) increased preoperatively, while the corneal spherical and trefoil aberrations were normal. After cataract surgery, the monocular triplopia disappeared and the ocular spherical and trefoil aberrations decreased.

Comparison between Anterior Corneal Aberration and Ocular Aberration in Laser Refractive Surgery

PURPOSE: To compare changes of anterior corneal aberration (Pentacam(R)) and ocular aberration (aberrometer, LADARWave(R)) after laser refractive surgery. METHODS: Sixty-six eyes underwent laser refractive surgery and were retrospectively reviewed. Anterior corneal aberration and ocular aberration were measured by Pentacam(R) and an aberrometer (LADARWave(R)) respectively. Changes of root mean square (RMS) values of coma, spherical aberration, and total high order aberration (HOA) were evaluated before, 1 month, and 3 months after surgery RESULTS: Ocular aberrations displayed low preoperative values, but after laser refractive surgery, anterior corneal aberration and ocular aberration increased equally. There were no statistically significant differences of internal optics aberration values (ocular aberration minus anterior corneal aberration) in coma, spherical aberration, and total HOA. Anterior corneal aberration and ocular aberration showed statistically significant correlations at 1 and 3 months after surgery. CONCLUSIONS: Internal optics aberration compensated the anterior corneal aberration effectively before surgery, but the increase of anterior corneal aberration after laser refractive surgery exceeded the compensation of internal optics. As a result, anterior corneal aberration and ocular aberration increased equally. The correlation between anterior corneal aberration and ocular aberration after surgery was statistically significant due to the increased proportion of anterior corneal aberration in ocular aberration.

Higher-order Aberrations in Pseudophakia with Different Intraocular Lenses

PURPOSE: To compare high-order aberrations in the pseudophakia with different types of intraocular lenses (IOLs), as well as with normal phakic eyes. METHODS: This single-center prospective study comprised 80 cataract patients who underwent cataract surgery and 20 phakic eyes. Twenty eyes received an AF-1(R) VA-60BB; 20 eyes, a Corneal(R) ACR6D SE; 20 eyes, a Sensar(R) AR40e; and 20 eyes, a ClariFlex(R). One month after cataract surgery, the eye aberration was measured using a Hartmann-Shack type aberrometer. The same test was performed for 20 normal phakic eyes. The individual Zernike polynomials, the root mean square (RMS) values of the third and fourth order aberration, and the total RMS among the groups were compared. RESULTS: The individual Zernike coefficient (Z3(-1), Z3(3), Z4(-4), Z4(0), Z4(4)) showed a significant difference in the IOL-implanted groups compared with the normal phakic eyes. There were statistically significant differences in the RMS values of the third and fourth order aberration, and total among each group. CONCLUSIONS: There was a statistically significant increase in aberration in patients with high refractive index IOL and a statistically significant decrease in patients with silicone IOL, compared to the normal phakic eyes.

The Change of Ocular Aberration after LASIK Surgery

PURPOSE: To evaluate the change of ocular aberration after LASIK using Zernike's polynomial expansions. METHODS: Sixty eyes of thirty consecutive patients that underwent LASIK were examined prospectively. The ocular aberration was measured with Hartman-Shack aberrometer (WASCA Wavefront Analyzer, USA) at postoperative 30, 90, and 180 days. The postoperative values were compared with that of preoperation. RESULTS: The average age is 27.6 years old. The range of preoperative refractory error were from -3.00 Diopter (D) to -11.00 D. The increase of spherical and triangular coma aberrations (4.7- fold and 3.5- fold, respectively), with respect to preoperative values. There were statistically significant differences between preoperative and postoperative high order RMS at the postoperative 180 days (p<0.05). CONCLUSIONS: The postoperative increases of RMS in higher order aberration, coma aberration, triangular aberration was observed.