Conductive keratoplasty for symptomatic presbyopia following monofocal intraocular lens implantation

BCLA CLEAR Presbyopia: Management with corneal techniques

Corneal techniques for enhancing near and intermediate vision to correct presbyopia include surgical and contact lens treatment modalities. Broad approaches used independently or in combination include correcting one eye for distant and the other for near or intermediate vision, (termed monovision or mini-monovision depending on the degree of anisometropia) and/or extending the eye's depth of focus [1]. This report reviews the evidence for the treatment profile, safety, and efficacy of the current range of corneal techniques for managing presbyopia. The visual needs and expectations of the patient, their ocular characteristics, and prior history of surgery are critical considerations for patient selection and preoperative evaluation. Contraindications to refractive surgery include unstable refraction, corneal abnormalities, inadequate corneal thickness for the proposed ablation depth, ocular and systemic co-morbidities, uncontrolled mental health issues and unrealistic patient expectations. Laser refractive options for monovision include surface/stromal ablation techniques and keratorefractive lenticule extraction. Alteration of spherical aberration and multifocal ablation profiles are the primary means for increasing ocular depth of focus, using surface and non-surface laser refractive techniques. Corneal inlays use either small aperture optics to increase depth of field or modify the anterior corneal curvature to induce corneal multifocality. In presbyopia correction by conductive keratoplasty, radiofrequency energy is applied to the mid-peripheral corneal stroma, leading to mid-peripheral corneal shrinkage and central corneal steepening. Hyperopic orthokeratology lens fitting can induce spherical aberration and correct some level of presbyopia. Postoperative management, and consideration of potential complications, varies according to technique applied and the time to restore corneal stability, but a minimum of 3 months of follow-up is recommended after corneal refractive procedures. Ongoing follow-up is important in orthokeratology and longer-term follow-up may be required in the event of late complications following corneal inlay surgery.

A systematic review of pseudophakic monovision for presbyopia correction

A systematic review of the recent literature regarding pseudophakic monovision as a reliable methods for presbyopia correction was performed based on the PubMed, MEDLINE, Nature and the American Academy of Ophthalmology databases in July 2015 and data from 18 descriptive and 12 comparative studies were included in this narrative review. Pseudophakic monosvision seems to be an effective method for presbyopia with high rates of spectacles independence and minimal dysphotopsia side-effects, that should be considered by the modern cataract surgeons.

Corneal Refractive Procedures for the Treatment of Presbyopia

Purpose:

Refractive surgery has been in use for a long time and is evolving at a fast pace with several new corneal procedures being used for the correction of presbyopia. The purpose of this article is to give a comprehensive review of the literature to evaluate the outcome and success of different corneal refractive surgical procedures in presbyopic patients.

Methods:

We performed a comprehensive search on PubMed to identify published reports of the various procedures utilized in the past and present to correct presbyopia. The outcomes of these procedures were recorded.

Results and conclusion:

We found that varying rates of success have been reported with these procedures. The results of our exhaustive search are presented in this report for review.

Corneal-Based Surgical Presbyopic Therapies and Their Application in Pseudophakic Patients

Purpose. The purpose of this review is to provide a summary of laser refractive surgery and corneal inlay approaches to treat presbyopia in patients after cataract surgery. Summary. The presbyopic population is growing rapidly along with increasing demands for spectacle independence. This review will focus on the corneal-based surgical options to address presbyopia including various types of corneal intrastromal inlays and laser ablation techniques to generate either a multifocal cornea (“PresbyLASIK”) or monovision. The natural history of presbyopia develops prior to cataracts, and these presbyopic surgeries have been largely studied in phakic patients. Nevertheless, pseudophakic patients may also undergo these presbyopia-compensating procedures for enhanced quality of life. This review examines the published reports that apply these technologies to patients after cataract surgery and discusses unique considerations for this population.

Corrective Techniques and Future Directions for Treatment of Residual Refractive Error Following Cataract Surgery

Postoperative residual refractive error following cataract surgery is not an uncommon occurrence for a large proportion of modern-day patients. Residual refractive errors can be broadly classified into 3 main categories: myopic, hyperopic, and astigmatic. The degree to which a residual refractive error adversely affects a patient is dependent on the magnitude of the error, as well as the specific type of intraocular lens the patient possesses. There are a variety of strategies for resolving residual refractive errors that must be individualized for each specific patient scenario. In this review, the authors discuss contemporary methods for rectification of residual refractive error, along with their respective indications/contraindications, and efficacies.

Presbyopic correction on the cornea

Purpose

The aim of this systematic review was to synthesize and appraise the evidence of the benefits of presbyopic correction on the cornea for visual function.

Summary

Comprehensive search was conducted in MEDLINE using keywords like “presbylasik”, “presbyopic refractive surgery”, “corneal pseudoaccommodation” and “corneal multifocality”. We reviewed corrected and uncorrected visual acuities for distance and near (uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), distance corrected near visual acuity (DCNVA), corrected near visual acuity (CNVA)), along with the refractive outcomes in spherical equivalent (SE) and astigmatism comparing the differences observed between preoperative myopic and hyperopic patients, as well as among techniques.

Thirty-one studies met the inclusion and quality criteria. Monovision provides excellent distance and near uncorrected acuities, but with a 17% retreatment and a 5% reversal rate. Initial multifocal ablations result in 12% loss of 2 or more lines of CDVA, and a 21% retreatment rate. Laser Blended Vision provides excellent UDVA, but with a 19% retreatment rate. Initial experiences with Supracor show moderate predictability and a 22% retreatment rate. Intracor results in 9% loss of 2 or more lines of CDVA. KAMRA provides excellent UDVA, with only a 1% retreatment rate, but a 6% reversal rate. Initial experiences with PresbyMAX provided excellent UNVA and DCNVA, showing excellent predictability and a 1% reversal rate.

Conclusions

The findings have implications for clinicians and policymakers in the health-care industry and emphasize the need for additional trials examining this important and widely performed clinical procedure.

Conductive keratoplasty: an approach for the correction of residual hyperopia in post-lasik pseudophakia

Although there are many formulae for the calculation of intraocular lens power in the eyes with previous kerato-refractive surgeries, unexpected refractive bias still exists. Hyperopic bias is particularly disliked because it affects both uncorrected distance and near visual acuity. Surgical treatment of the residual hyperopia for the eyes with both laser in situ keratomileusis and cataract surgery remains to be a big problem. Conductive keratoplasty has been shown to be an effective, safe and predictable method for low and moderate hyperopia in the pseudophakic eyes or in the eyes with kerato-refractive surgeries. However, the efficacy and safety of conductive keratoplasty in the correction of residual hyperopia after both corneal and lens refractive surgeries has not been reported. Herein, we reported the surgical correction with conductive keratoplasty for cases of residual hyperopia with/without astigmatism after previous laser in situ keratomileusis for high myopia and following phacoemulsification combined with posterior intraocular lens implantation for complicated cataract.