Refractive Lens Exchange with Acri.LISA Bifocal Intraocular Lens Implantation

Visual And Refractive Outcomes In Hyperopic Pseudophakic Patients Implanted With A Trifocal Intraocular Lens

Purpose

To assess visual and refractive results after bilateral implantation of a trifocal intraocular lens (IOL) in patients with hyperopia.

Methods

In a retrospective nonrandomized study, 196 eyes of 98 patients had bilateral implantation of a trifocal IOL. The Barrett Universal II formula was used for IOL power calculation. Eyes were divided into two groups for their analysis: low-moderate, with IOL power ranging from 22 to 26 D, and high, with IOL power ranging from 25 to 34 D. Refractive error was used to assess predictability, and corrected distance visual acuity (CDVA) and uncorrected distance visual acuity values were used to assess efficacy and safety of the surgery.

Results

Six months postoperatively, our results revealed a Snellen decimal CDVA of 0.97±0.05 and 0.94±0.09, for the low-moderate and high groups, respectively. The low-moderate hyperopia group showed a 75.23% of eyes with 20/20 of CDVA and 100% of eyes with 20/25 of CDVA, and the high hyperopia group showed 60.95% and 94.29% for these values of visual acuity, respectively. The mean postoperative spherical equivalent was -0.25±0.36D and -0.24±0.42D for low-moderate and high hyperopia groups, respectively. In the case of low-moderate hyperopia group, 81% of eyes were within ±0.50D and 99% within ±1.00D. These values were 78% and 95%, respectively, for the high hyperopic eyes.

Conclusion

Bilateral implantation of a trifocal IOL in hyperopic eyes provided good visual and refractive outcomes. The Barrett Universal II formula was accurate in predicting the IOL power in hyperopic eyes.

Modern Phacoemulsification and Intraocular Lens Implantation (Refractive Lens Exchange) Is Safe and Effective in Treating High Myopia

Improved efficacy, predictability, and safety of modern phacoemulsification have resulted in cataract surgery being considered as a refractive procedure. Refractive lens exchange by definition is a surgery aimed at replacing the cataractous or clear crystalline lens with an intraocular lens (IOL) in cases of high ametropia. The excellent intraocular optics of this procedure provide a better visual outcome as compared with laser refractive surgery in high myopia. With advances in technology and IOL formulas, the predictability of refractive outcome after cataract surgery in high myopes has improved. The option of addressing presbyopia using multifocal/accommodating IOLs or monovision results in patients achieving reasonable spectacle independence. The most important concern with respect to phacoemulsification in high myopia is the risk of pseudophakic retinal detachment. High myopia is an independent risk factor for retinal detachment, and recent publications have reported a much lesser risk of retinal detachment specifically attributable to phacoemulsification in high myopes, especially if a thorough posterior segment evaluation is done and patients are followed up until development of complete posterior vitreous detachment. Refractive lens exchange is an effective and safe option to correct high myopia and can significantly improve quality of life in select patients.

Developments in the correction of presbyopia II: surgical approaches

PURPOSE

To discuss the various static and dynamic surgical approaches which attempt to give presbyopes good vision at far, intermediate and near viewing distances.

CONTENT

Static methods broadly adopt the same optical techniques as those used in presbyopic contact lens correction and aim to satisfy the needs of the presbyope by increasing binocular depth-of-focus, often using monovision as well as simultaneous-imagery. Dynamic methods generally attempt to make use of at least some of the still-active elements of the accommodation system. They include procedures which are supposed to modify the relative geometry of the ciliary muscle and lens, or which reduce the stiffness of the presbyopic lens either by replacing it with other natural or man-made material or by subjecting it to femtosecond laser treatment. Alternatively the natural lens may be replaced by some form of intraocular lens which changes power as a result of forces derived from the still-active ciliary muscle, zonule and capsule, or other sources.

CONCLUSIONS

At present, multifocal intraocular lenses appear to offer the most consistent and reliable surgical approach to surgical presbyopic correction. They have obvious advantages in convenience and stability over optically-similar, simultaneous-image presbyopic contact lenses but this must be balanced against their relative inflexibility in cases of patient dissatisfaction. Dynamic methods remain largely experimental. Although some approaches show promise, as yet no method has demonstrated a reliable, long-term ability to correct distance refractive error and to appropriately change ocular power in response to changes in viewing distance over the normal range of interest.

Long-term results of clear lens extraction combined with piggyback intraocular lens implantation to correct high hyperopia

AIM

To assess the refractive outcome of clear lensectomy combined with piggyback intraocular lens implantation in highly hyperopic patients.

METHODS

This case review included 19 eyes of 10 patients with high hyperopia and axial length less than 21mm. Intraocular lens power was calculated for emmetropia using the Holladay II formula in 17 eyes, and SRK/T formula in 2 eyes following clear lens extraction and piggyback intraocular lens implantation. Patients were examined periodically over 24 months for visual acuity and spherical equivalent (SE).

RESULTS

The mean postoperative SE at 24 months was 0.20±1.39D (range, -3.00 to 2.50D), better than preoperative 9.81±2.62D (range, +6.00 to +14.50D) (P<0.001). Five eyes had SE within ±0.5D of emmetropia and 11 eyes within ±1.00D at postoperative 24 months. The mean postoperative uncorrected visual acuity (UCVA) at 24 months was 0.60±0.36, significantly improved compared to preoperative 1.39±0.33 (P<0.001). The mean best-corrected visual acuity (BCVA) at 24 months was 0.49±0.35, not statistically different compared to preoperative 0.38±0.30 (P=0.34). Twelve eyes maintained and 1 gained 1 or more Snellen line of BCVA, 4 eyes lost 1 line, and 2 eyes lost 2 lines at 24 postoperative months. Twelve eyes best-corrected near visual acuity (BCNVA) achieved J1 at postoperative 24 months compared to preoperative 7 eyes and the other 7 eyes better than J3.

CONCLUSION

Clear lens extraction combined piggyback intraocular lens implantation appears to be an effective procedure to correct high hyperopia but mild overcorrection and intralenticular opacification may require secondary procedure.