Surgical Correction of Presbyopia: Lenticular, Corneal, and Scleral Approaches

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.

Defocus Curve of Emerging Presbyopic Patients

Purpose

To create a defocus curve of emerging presbyopic patients of various age groups.

Setting

Single site private practice in Sioux Falls, South Dakota.

Design

This was a non-randomized, prospective study. All subjects were enrolled from healthy volunteers.

Methods

Subjects aged 37-9, 40-42, 43-45 and 46-48 that have 20/20 best-corrected distance visual acuity (BCDVA) were included. Binocular visual acuity at different defocus steps ranging from +0.5 D to -3 D was measured in each age group. Defocus curves were generated from the mean logMAR visual acuities at each defocus step, by age group.

Results

Of the 60 subjects, 23.3% of subjects were between the ages of 37-39, 26.7% were between the ages of 40-42, 25% of subjects were between ages 43-45, and 25% were between the ages of 46-48. Visual acuity significantly decreased from plano to -3 D defocus steps in all groups (p < 0.0002, p = 0, p = 0 and p = 0). The 46-48-year-old group had worse visual acuity compared to the other three groups from the -1.0 to -2.0 D defocus steps (p = 0.037, p = 0.022 and 0.017, respectively). Starting at a near point of 40cm, the 37-39 group had the best logMAR vision and the 46-48 group had the worst vision (p = 0.001).

Conclusion

The defocus curves of emerging presbyopic individuals demonstrate a decreasing visual acuity at near defocus steps that decreases with age. Defocus curves at different age ranges can help doctors explain various presbyopia treatment options in terms of near point capabilities at various ages.

Explantation of KAMRA Corneal Inlay: 10-Year Occurrence and Visual Outcome Analysis

PURPOSE

To evaluate 10 years of KAMRA corneal inlay explantation and associated visual outcomes.

PATIENTS AND METHODS

Single-site retrospective chart review of 22 cases of AcuFocus KAMRA Inlay (ACI7000PDT) explantation (range 1 week-1 year). Uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), and manifest refraction at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year post-explantation were reviewed.

RESULTS

The explantation rate was 8.2% across 10 years. All patients underwent KAMRA explantation due to dissatisfaction with their vision including blurry near vision, impaired night vision, decreased vision in dim lighting, streaks or halos, haze, and double vision. Mean UDVA pre-implant was -0.01±0.13 logMAR (logarithm of the minimal angle of resolution), 0.30±0.22 logMAR pre-explant, and 0.16±0.15 logMAR post-explant (n=20). Mean UNVA pre-implant was 0.37±0.09 logMAR, 0.38±0.13 logMAR pre-explant, and 0.42±0.21 logMAR post-explant (n=20). Mean CDVA pre-implant was -0.01±0.04 logMAR and 0.05±0.11 logMAR post-explant (n=17). Mean CDVA pre-explant was 0.04±0.07 logMAR and 0.04±0.11 logMAR post-explant (n=19). Significant differences were observed between pre-implant and post-explant UDVA (p=0.009), and between pre-explant and post-explant UDVA (p=0.02). All patients (100%) had 20/20 or better CDVA pre-implant but decreased to 73.7% post-explant. Sixty percent (12/20) of the patients lost UDVA Snellen acuity lines post-explant. MRSE was -0.31±0.29 D pre-implant and +0.26±0.77 D post-explant (p=0.007) with note of a hyperopic shift. The hyperopic shift in 31.6% (6/19) of patients did not resolve after explantation. Post-explant residual corneal haze occurred in 72.7% (16/22) of patients.

CONCLUSION

Although the KAMRA corneal inlay is a removable device, patients may experience residual corneal haze, hyperopic shift, and deficits in UDVA after explantation compared to pre-implantation UDVA.

Review of Presbyopia Treatment with Corneal Inlays and New Developments

Presbyopia may represent the largest segment of refractive errors that is without an established and effective refractive surgery treatment. Corneal Inlays are materials (synthetic or allogenic) implanted in the stroma of patients’ corneas to improve presbyopia. These inlays, introduced into the United States in 2015 via the small-aperture corneal inlay (KAMRA^TM, SightLife Surgical/CorneaGen, Seattle, Washington, United States), were met with an initial wave of enthusiasm. Subsequent models like the shape-changing corneal inlay (RAINDROP^TM, Revision Optics, Lake Forest, California, United States) offered excellent results for patients, but longer-term research raised questions about patient safety. At the time of this article, no synthetic corneal inlays are available in the United States for the correction of presbyopia. Other options for presbyopia correction include allograft corneal inlays, trifocal synthetic corneal inlays, pharmacologic therapies, scleral incisions or additive techniques and PresbyLASIK. Presently, allograft inlays consist of corneal lenticules removed from patients undergoing Small Incision Lenticule Extraction (SMILE). We will review corneal inlays and other alternative procedures that may provide effective and predictable treatments for patients with presbyopia.

Preliminary Clinical Outcomes of a New Enhanced Depth of Focus Intraocular Lens

Purpose

To assess the preliminary clinical outcomes and patient satisfaction of the new enhanced depth of focus (EDOF) LuxSmart™ intraocular lens IOL and to compare with a conventional monofocal IOL (Akreos™) in patients who had undergone bilateral cataract surgery.

Methods

Twelve patients underwent bilateral LuxSmart IOL implantation, and twelve underwent bilateral Akreos IOL implantation. Best-corrected distance (CDVA) and uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA) at 66cm, uncorrected near visual acuity (UNVA) at 40cm and defocus curve were assessed. Patients-reported visual function was inquired by Catquest-9SF. The presence of photic phenomena was evaluated. A p-value lower than 0.05 was considered for statistical significance.

Results

The mean IOL power was +21.90D in LuxSmart group and +22.30D in Akreos. Monocular UDVA (p = 0.32) and CDVA (p = 0.52) did not differ between groups. The average binocular UIVA (0.18 ± 0.12 logMAR vs. 0.30 ± 0.13 logMAR, p < 0.001) and UNVA (0.38 ± 0.14 logMAR vs. 0.44 ± 0.17 logMAR, p = 0.02) were higher in LuxSmart IOL group. No patients reported disabling photic phenomena in either group.

Conclusion

This study shows that new LuxSmart EDOF IOL achieved higher performance for intermediate and near vision compared with a conventional monofocal IOL, without increasing the risk of dysphotopsias. LuxSmart may be an attractive and safe option for patients who desire spectacle independence for distance and intermediate vision after cataract surgery.

A multicentric study of pharmacological treatment for presbyopia

PURPOSE

To evaluate the safety, efficacy, and patient satisfaction with a pharmacological treatment of presbyopia performed with the Benozzi's method.

METHODS

A non-randomized multicentric case-series retrospective study was developed. Were included patients from 5 centers of Argentina, from January 2010 to June 2019, aged at baseline between 40 and 60 years old, with binocular uncorrected distance visual acuity (UDVA) of 25/20 or better, and with uncorrected near visual acuity (UNVA) at least Jaeger (J) 2 or worse. The treatment was performed with a patented formulation (pilocarpine and diclofenac preservative-free eye drops). The main outcome was binocular UNVA and UDVA. Differences were evaluated by paired t-test. The presence of side effects and patient's satisfaction were also evaluated. Data was analyzed in separated groups according to their follow-up time, from 2 to 10 years.

RESULTS

A total of 148 patients were included. At baseline, the UNVA for the different groups were between J3 and J8 which was improved to J1 to J2. The mean baseline UDVA has been ranged between 0.02 and 0.04 logMAR. The mean baseline UDVA has been ranged between 0.02 to 0.04 logMAR, after treatment were between 0.01 to 0.03, without a statisticallysignificant improvement. Side effects were spontaneously resolved, and subjective evaluation shows that patients were satisfied.

CONCLUSIONS

This first multicentric shows that Benozzi's method for presbyopia treatment was safety and improves the UNVA without affecting the UDVA, maintaining their efficacy even after 10 years, in a population aged between 40 and 60 years old, from different ophthalmic centers in Argentina.

A preliminary study on the visual outcomes after LaserACE for presbyopia

Background

To investigate the visual outcomes over 1 year after laser anterior ciliary excision (LaserACE) procedure for presbyopic subjects.

Methods

A prospective, non-randomized, non-comparative study. Eight emmetropic eyes of four patients with presbyopia were included in this study. All eyes were treated with the LaserACE procedure using the VisioLite erbium-YAG laser (Ace Vision Group, USA). Subjects were assessed preoperatively and at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year postoperatively. Outcome measures included questionnaires, visual acuity, manifest refraction, pupil size, keratometry, reading prescription, and intraocular pressure.

Results

Binocular distance corrected intermediate visual acuity (DCIVA) had improved from 0.33±0.12 logMAR to 0.12±0.12 logMAR after 6 months (P<0.05) and 0.13±0.12 logMAR after 12 months postoperatively (P<0.01). Binocular distance corrected near visual acuity (DCNVA) improved from 0.41±0.10 logMAR to 0.24±0.12 logMAR after 6 months (P<0.05) and 0.26±0.09 log MAR after 12 months postoperatively (P<0.05). An average decrease of 0.91±0.28 D in the reading prescription at a 40 cm reading distance was observed and remained stable over 12 months (P<0.05). There were no significant differences in manifest refraction, uncorrected distance visual acuity (UDVA), corneal curvature, high order aberrations, pupil size compared with preoperative and 6 months as well as 12 months postoperative visits (P>0.05).

Conclusions

The LaserACE procedure is shown to be safe and efficient for presbyopia correction without influencing distance vision or visual quality. However, its mechanism and long-term effects need further validation.

Presbyopia Treatment With Eye Drops: An Eight Year Retrospective Study

Purpose

The purpose of this study was to evaluate the safety and efficacy across time, of patients topically treated with Benozzi's method for presbyopia.

Methods

A nonrandomized case series retrospective study was developed, including patients with emmetropia with binocular uncorrected distance visual acuity (UDVA) of 25/20 or better, and with uncorrected near visual acuity (UNVA) at least Jaeger 2 or worse. The study was set in Buenos Aires, Argentina, from January 2011 to June 2018, with at least 1-year follow-up. Patients were treated with pilocarpine and diclofenac preservative-free eye drops (Benozzi Method; US 8.524.758 B2, EP1.938.839 B1), and the main outcome measured was binocular UNVA at different follow-up times. Other parameters, as the UDVA and presence of side effects, were evaluated.

Results

A total of 910 patients were included with a mean age at baseline of 48.67 ± 3.72 years old (range, 40–59 years). The baseline UNVA was 4.74 ± 1.53 and at 8 years of follow-up was decreased to 1.36 ± 0.48 (Jaeger scale). The mean binocular UDVA at baseline was 0.00 ± 0.01 logarithm of the minimum angle of resolution (logMAR) and after 8 years of follow-up was 0.03 ± 0.04 logMAR. All side effects reported (decrease of light perception, headaches, symptoms of ocular surface dryness, and dizziness) were spontaneously resolved in patients who continued with the treatment.

Conclusions

The efficacy of the pharmacological treatment of presbyopia to improve the UNVA without affecting the UDVA is shown. Side effects were well tolerated and resolved before 1 year of treatment.

Translational Relevance

This is a nonsurgical option for patients with emmetropic presbyopia who do not wish to wear glasses, which is a pharmacological treatment with eye drops.

A Review of Presbyopia Treatment with Corneal Inlays

The prevalence of presbyopia continues to increase every year. The therapeutic approaches to presbyopia cover the spectrum of non-surgical to surgical techniques. With recent advances in biocompatible materials, corneal inlays make a strong case for their place within the treatment spectrum. This article takes a closer look at three of the current corneal inlay models: KAMRA, Raindrop, and Presbia Flexivue Microlens. Each design approach and mode of action is described with data from key clinical trials. Furthermore, the ability to choose the most suitable corneal inlay is presented by comparing each model and identifying their similarities and differences. The article then concludes by touching on the future of corneal inlays, looking at associated conditions and complications and how to manage them, as well as an expert’s personal point of view of enhanced ideas for continuing the growth and success of corneal inlays in the market.