Visual Outcomes and Safety of a Small Diameter Intrastromal Refractive Inlay for the Corneal Compensation of Presbyopia

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.

Visual Outcomes and Safety of a Refractive Corneal Inlay for Presbyopia: One-Year Results

PURPOSE

To determine the visual outcomes and safety 12 months after implantation of the Presbia Flexivue Microlens refractive corneal inlay.

METHODS

In this prospective, non-randomized trial, 22 patients with a mean age of 52.54 ± 2.86 years were implanted with the Flexivue Microlens refractive corneal inlay in the non-dominant eye at the Department of Ophthalmology, Goethe University, Frankfurt, Germany. Corrected near, intermediate, and distance (CNVA, CIVA, and CDVA) visual acuity and uncorrected near, intermediate, and distance (UNVA, UIVA, and UDVA) visual acuity, manifest refraction, subjective quality of vision, endothelial cell count, and contrast sensitivity were measured 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively.

RESULTS

For binocular CDVA, no patient lost two or more lines and 30% lost only one line at the 12-month visit. In the eye that had surgery, 85% of the patients lost two or more lines of UDVA, which was statistically significant. Sixty-five percent of the patients gained one or more lines in binocular UIVA, and 80% achieved 20/40 or better in DCIVA. UNVA showed a statistically significant improvement, with 90% of the patients achieving 20/40 or better 12 months after implantation. A total of 85% gained two or more lines in binocular UNVA.

CONCLUSIONS

This refractive corneal inlay showed an improvement in binocular UNVA, UIVA, CNVA, and CIVA, whereas binocular CDVA and UDVA were not statistically affected. [J Refract Surg. 2024;40(1):e1-e9.].

Efficacy, Safety, Predictability, and Stability of LASIK for Presbyopia Correction: A Systematic Review and Meta-analysis

PURPOSE

To determine the efficacy, safety, predictability, and stability of laser in situ keratomileusis (LASIK) in the treatment of presbyopia.

METHODS

The databases of CNKI, VIP, Wan-Fang, CBM, Chinese Clinical Registry, PubMed, The Cochrane Library, Web of Science, Embase, and ClinicalTrials.gov were searched until March 2023. The authors chose the studies of LASIK in the treatment of presbyopia. Outcomes were efficacy, safety, predictability, and stability. The review was registered in the international platform of registered systematic review and meta-analysis protocols (INPLASY202350005).

RESULTS

A total of 28 non-randomized controlled trials (15,861 eyes) were included. The results showed that after LASIK, (1) the distance efficacy decreased (mean difference [MD]: 0.02, 95% CI: 0.0 to 0.03, P < .05) and the near efficacy increased (MD: -0.01, 95% CI: -0.19 to-0.02, P < .05); (2) the distance safety decreased (MD: 0.07, 95% CI: 0.04 to 0.10, P < .0001) and near safety increased (MD: -0.19, 95% CI: -0.39 to 0.02, P > .05); (3) the predictability within ±1.00 and ±0.50 D was 94% (relative risk [RR]: 0.94, 95% CI: 0.90 to 0.98, P < .001) and 80% (RR: 0.80, 95% CI: 0.74 to 0.86, P < .001), respectively; and (4) 6 months postoperatively, the percentage of spherical equivalent changing within ±0.50 D was 95% (RR: 0.95, 95% CI: 0.89 to 0.99, P < .001).

CONCLUSIONS

The near efficacy, predictability, and stability of LASIK for presbyopia correction were satisfactory; however, the distance efficacy and distance safety decreased. [J Refract Surg. 2023;39(9):627-638.].

Refractive corneal inlay implantation outcomes: a preliminary systematic review

PURPOSE

To review all case series of refractive corneal inlay implantation: Flexivue (Presbia, Netherlands), Invue (BioVision, Brügg, Switzerland) and Icolens (Neoptics, Hünenberg, Switzerland) performed in presbyopia patients and to evaluate the reported visual outcomes. In addition, our aim is to provide assessment for complications and to report the satisfaction rates.

METHODS

PubMed, Web of Science and Scopus databases were consulted using "refractive corneal inlay", "Flexivue Inlay", "Invue Inlay" and "Icolens inlay" as keywords. 147 articles were found, and they were assessed considering the inclusion and exclusion criteria. After filtering, this systemic review included ten articles, published between 2011 and 2020.

RESULTS

308 eyes from 308 participants were enrolled in this systematic review. Mean maximum follow-up was 13.9 months. Nine of the ten case series included used femtosecond laser for the corneal pocket creation. Mean pocket depth was 293.75 µm. 77.5% of the eyes reported a postoperative uncorrected near visual acuity of 20/32 or better, and 19.20% of the inlay-implanted eyes achieved an uncorrected distance visual acuity of 20/20 or better. The most prominent complications were halos, pain, photophobia, and poor distance visual acuity. 27 eyes (8.7%) had to be explanted due to complications, such as near-distance spectacle dependence or blurred distance vision.

CONCLUSION

Refractive corneal inlay outcomes demonstrated high efficacy, safety, and satisfaction rates. Furthermore, it is a reversible technique. However, the findings must be viewed with caution due potential conflict of interest. Further research with higher sample size is needed to validate these findings.

Correction of pseudophakic presbyopia using Lasik with aspheric ablation profiles and a micro-monovision protocol

PURPOSE

To evaluate the outcomes of Lasik with aspheric ablation profiles and a micro-monovision protocol for correction of presbyopia in pseudophakic patients.

PATIENTS AND METHODS

This study included 50 pseudophakic eyes of 25 patients. Full ophthalmic examination, dominant eye tests and tests for tolerance of anisometropia (1 or 2 diopters) were done preoperatively. All cases were treated by Lasik with laser-blended vision technique. The dominant eye corrected to plano, and the nondominant eye corrected with near add in the range from 1.50 to 2.00 diopters. Excimer laser ablation was done using the MEL90 with a 250-Hz pulse rate (Carl Zeiss Meditec, Jena, Germany, Triple-A profile, Lasik mode). The follow-up period was 6 months with visits at 1, 3 and 6 months postoperatively.

RESULTS

The mean postoperative uncorrected distant visual acuity at 1 month (0.74 ± 0.11) was significantly lower than the preoperative level (0.84 ± 0.14) (p < 0.001). But it improved at the 3rd (0.80 ± 0.09) and 6th months (0.82 ± 0.10) with no significant difference with the preoperative level (p = 0.344). The mean uncorrected near visual acuity was significantly higher at the 1st (2.94 ± 1.63 J), 3rd (2.95 ± 1.82 J) and 6th (2.92 ± 1.83 J) postoperative months than the preoperative level (2.26 ± 1.48 J) (p < 0.001). Insignificant change in stereopsis was found after surgery (p = 0.849). The micro-monovision was well tolerated (95.8%).

CONCLUSION

Lasik with aspheric ablation profiles and a micro-monovision protocol is an effective option for presbyopia correction in pseudophakic patients.

The Effect of Intraoperative Angle Kappa Adjustment on Higher-Order Aberrations Before and After Small Incision Lenticule Extraction

PURPOSE

To compare higher-order aberrations (HOAs) after small incision lenticule extraction (SMILE) in patients with and without intraoperative angle kappa adjustments.

METHODS

This is a retrospective case series. One hundred six eyes of 106 patients who underwent SMILE at Tianjin Eye Hospital (Tianjin Medical University, Tianjin, China) for correction of myopia and myopic astigmatism were divided into 2 groups. The first group consisted of eyes with intraoperative angle kappa adjustment and the second group consisted of eyes without adjustment. Preoperative and postoperative visual outcome, refraction, and HOA measurements at 1 and 3 months were compared.

RESULTS

At the pupil size of 6 mm, vertical coma at 1 and 3 months after SMILE for the angle kappa-adjusted group was 0.153 ± 0.107 and 0.157 ± 0.094 μm, which were significantly lower than those of the nonadjusted group (0.204 ± 0.117 and 0.203 ± 0.113 μm, respectively) (P = 0.026 at 1 mo, P = 0.047 at 3 mo). The change in vertical coma between preoperative and postoperative measurements was 0.011 ± 0.136 and 0.023 ± 0.129 μm at 1 and 3 months postoperatively for the angle kappa-adjusted group, which were lower than those of the nonadjusted group (0.082 ± 0.165 and 0.085 ± 0.150 μm, respectively) (P = 0.023 at 1 mo, P = 0.045 at 3 mo). Subgroup analysis for eyes with large angle kappa demonstrated that the vertical coma was significantly less in the angle kappa-adjusted group at both 1 and 3 months (P = 0.009, P = 0.043, respectively). No significant correlation was observed between angle kappa and HOAs in the angle kappa-adjusted group.

CONCLUSIONS

Adjustment of angle kappa during SMILE resulted in less HOAs. It would provide more insight on how to optimize treatment centration in SMILE.

Confocal and Histological Features After Poly(Ethylene Glycol) Diacrylate Corneal Inlay Implantation

Purpose

To evaluate the in vivo biocompatibility of photopolymerized poly(ethylene glycol) diacrylate (PEGDA) intrastromal inlays in rabbit corneas.

Methods

Sixty-three eyes of 42 New Zealand rabbits were included. Manual intrastromal pockets were dissected in 42 eyes. PEGDA inlays were obtained using a specifically designed photomask and were inserted in the intrastromal pocket of 21 eyes (inlay group); the remaining 21 right eyes did not receive any implant (pocket-only group). Twenty-one eyes with no intervention were used as controls. In vivo confocal microscopy (IVCM) was performed at every visit. After 2 months, rabbits were sacrificed and corneas removed for histological analysis.

Results

Corneas remained clear in all but two animals, and five cases of corneal neovascularization were seen (P = 0.2). Inlays remained stable without evidence of lateral or anterior migration, and no other complications were observed. No changes in anterior and posterior keratocyte density (P = 0.3 and P = 0.1, respectively) or endothelial cell density (P = 0.23) were observed between groups during the study time by IVCM. On pathology samples, thinning of the epithelium over the inlay area and epithelial hyperplasia over the edges were observed. A polygonal empty space with no evidence of PEGDA hydrogel within the midstroma was seen in the inlay group. Keratocytes were normal in shape and number in the vicinity of the PEGDA implant area.

Conclusions

Photopolymerized PEGDA intrastromal inlays have shown relatively good safety and stability in rabbit corneas. Inlays were biostable in the corneal environment and remained transparent during follow up.

Translational Relevance

The investigated PEGDA is promising for the development of biocompatible intrastromal implants.

One-Year Clinical Outcomes of a Corneal Inlay for Presbyopia

PURPOSE

To report the results of a 1-year follow-up analysis of the safety and efficacy of the Flexivue Microlens corneal inlay.

METHODS

The Flexivue Microlens corneal inlay was implanted in the nondominant eye of patients with emmetropic presbyopia (a spherical equivalent of -0.5 to 1.00 diopter) after the creation of a 300-μm deep stromal pocket, using a femtosecond laser. The patients were followed up according to a clinical protocol involving refraction, anterior segment imaging analysis (Oculyzer), and optical quality analysis (OPD-Scan).

RESULTS

Thirty-one patients were enrolled in this ongoing study. The mean age was 50.7 years (range 45-60 yrs), and 70% of the patients were female. The mean uncorrected near visual acuity improved to Jaeger 1 in 87.1% of the eyes treated with the inlays. All eyes improved 4 lines at all visits. The binocular uncorrected distance visual acuity was 20/20 in all patients. Ninety percent of the patients reported that their near vision was good or excellent. Some of the patients (16.1%) lost more than 3 lines of corrected distance visual acuity. At the latest follow-up, induction of a corneal spherical aberration to improve near visual acuity was statistically significant. No other intraoperative or postoperative complication was noted.

CONCLUSIONS

The Flexivue Microlens provided patients with improved near vision, as a result of a negative spherical aberration. A significant loss of corrected distance visual acuity in the operated eyes was observed. Overall, this intracorneal inlay was an effective alternative to other procedures for the correction of presbyopia.

A Novel Laser Refractive Surgical Treatment for Presbyopia: Optics-Based Customization for Improved Clinical Outcome

Laser Assisted in Situ Keratomileusis (LASIK) is a proven treatment method for corneal refractive surgery. Surgically induced higher order optical aberrations were a major reason why the method was only rarely used to treat presbyopia, an age-related near-vision loss. In this study, a novel customization algorithm for designing multifocal ablation patterns, thereby minimizing induced optical aberrations, was used to treat 36 presbyopic subjects. Results showed that most candidates went from poor visual acuity to uncorrected 20/20 vision or better for near (78%), intermediate (92%), and for distance (86%) vision, six months after surgery. All subjects were at 20/25 or better for distance and intermediate vision, and a majority (94%) were also better for near vision. Even though further studies are necessary, our results suggest that the employed methodology is a safe, reliable, and predictable refractive surgical treatment for presbyopia.

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.

Changes in Keratometric Values and Corneal High Order Aberrations After Hydrogel Inlay Implantation

PURPOSE

We sought to analyze surgically induced refractive change (SIRC) and change in high-order aberration after Raindrop corneal inlay insertion (ReVision Optics, Lake Forest, CA), and assess the extent to which Raindrop corneal inlay insertion could correct presbyopia.

DESIGN

Interventional case series.

METHODS

Seventeen patients were included if they had a corneal thickness ≥500 μm and a stable manifest spherical equivalent refraction between 0.50 and +1.00 diopters (D). The Raindrop corneal inlay was implanted on the stromal bed of a femtosecond laser-assisted generated flap of nondominant eyes. Manifest refraction, corneal powers, and corneal high-order aberrations were measured preoperatively and at 3 and 12 months postoperatively.

RESULTS

The SIRC by manifest refraction was 0.99 ± 0.26 D. The changes derived from simulated keratometry (K), true net power, and equivalent K reading (EKR) at 1.0-4.0 mm were greater than the SIRC (all P < .01) while the change in EKR at 6.0 mm was less than the SIRC (P < .01). The changes in EKR 5.0 mm, automated K, and EKR 4.5 mm did not differ significantly from the SIRC (P = .81, .29, and .09, respectively), and the difference was the least for EKR 5.0 mm. In analysis of high-order aberrations, only spherical aberration showed statistically significant difference between preoperative and postoperative on both anterior cornea and total cornea (all P < .01).

CONCLUSION

Raindrop corneal inlay corrects presbyopia via increasing negative spherical aberration. The equivalent K reading at 5.0 mm accurately reflected the SIRC, and would be applicable for intraocular power prediction before cataract surgery.

Bifocal refractive corneal inlay implantation to improve near vision in emmetropic presbyopic patients

PURPOSE

To evaluate the safety and effectiveness of the Flexivue Microlens corneal inlay for the improvement of near vision in emmetropic presbyopic patients.

SETTING

Ophthalmology Department, Misericordia e Dolce Hospital, Prato, Italy.

DESIGN

Prospective interventional case series.

METHODS

Corneal inlay implantation was performed in nondominant eyes using a 150 kHz femtosecond laser (iFS). Refraction, uncorrected (UNVA) and corrected (CNVA) near visual acuities, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, slitlamp evaluation, wavefront aberrometry, photopic and mesopic contrast sensitivity, anterior segment optical coherence tomography, endothelial cell density, and central corneal thickness measurements were assessed preoperatively and at each postoperative visit.

RESULTS

The study evaluated 81 eyes. In 26 eyes, the mean preoperative UNVA and UDVA were 0.76 logMAR and 0.00 logMAR, respectively, compared with 0.10 logMAR and 0.15 logMAR, respectively, 36 months postoperatively. Sixteen (62%) of 26 treated eyes lost more than 1 line of UDVA, and 5 (19%) lost more than 2 lines of UDVA. Two eyes (8%) lost more than 1 line of CDVA at 36 months. The mean binocular UDVA was 0.00 logMAR preoperatively and 0.02 logMAR at 36 months. The mean spherical aberration increased after surgery. Statistically significant differences in the mean mesopic and photopic contrast sensitivities at higher spatial frequencies were found between treated eyes and nontreated eyes. Explantation was performed in 6 treated eyes because of halos, glare, and a reduced UDVA.

CONCLUSION

The corneal inlay might be a safe and effective method of improving UNVA in emmetropic presbyopic patients.

FINANCIAL DISCLOSURE

Dr. Fantozzi is a member of the Presbia medical advisory board. No other author has a financial or proprietary interest in any material or method mentioned.

One-year results of simultaneous laser in situ keratomileusis and small-aperture corneal inlay implantation for hyperopic presbyopia: comparison by age

PURPOSE

To compare by age the safety, efficacy, and patient satisfaction after simultaneous laser in situ keratomileusis (LASIK) and small-aperture corneal inlay implantation (Kamra) for hyperopic presbyopia.

SETTING

Shinagawa LASIK Center, Tokyo, Japan.

DESIGN

Retrospective comparative cohort study.

METHODS

Simultaneous LASIK and small-aperture corneal inlay implantation were performed in the nondominant eye of hyperopic presbyopic patients with astigmatism. Patients were divided into groups by age as follows: Group 1 (40 to 49 years), Group 2 (50 to 59 years), and Group 3 (60 to 65 years). The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, uncorrected near visual acuity (UNVA), and patient questionnaire results were compared.

RESULTS

The study evaluated 277 eyes of 277 patients. All groups achieved a mean UDVA of 20/20, with Group 1, Group 2, and Group 3 gaining 1 line, 2 lines, and 3 lines, respectively. The mean UNVA was J2 with 4 lines gained in Group 1 and J3 with 5 lines gained in Group 2 and Group 3. The mean CDVA and corrected near visual acuity remained the same as at baseline.

CONCLUSIONS

Simultaneous LASIK and small-aperture corneal inlay implantation for hyperopic presbyopia was a safe and effective treatment option. Although the outcomes were comparable between groups, Group 3 had the largest gain in UDVA and UNVA and the highest patient satisfaction, despite having the lowest reduction in dependence on reading glasses. Taking age into account might help achieve optimum postoperative outcomes and improved patient satisfaction.

FINANCIAL DISCLOSURE

Dr. Tomita is a consultant to Ziemer Ophthalmic Systems AG, Acufocus, Inc., and Schwind eye-tech-solutions GmbH and Co. KG. Dr. Waring is a consultant to Acufocus, Inc.

Central PresbyLASIK for Hyperopia and Presbyopia Using Micro-monovision With the Technolas 217P Platform and SUPRACOR Algorithm

PURPOSE

To analyze the refractive outcomes and satisfaction of presbyopic hyperopes treated with central presbyopicLASIK (presbyLASIK) with induced micro-monovision.

METHODS

This retrospective study included 74 eyes of 37 patients treated with central presbyLASIK with micro-monovision using the Technolas 217P excimer laser (Technolas Perfect Vision GmbH, Munich, Germany) between June 2011 and March 2014. Study parameters included uncorrected distance visual acuity (UDVA) and uncorrected near visual acuity (UNVA), aberrometry, the central steep zone, and patient satisfaction.

RESULTS

Median age was 54.3±4 years (range: 46 to 63 years). Mean postoperative spherical equivalent refraction was 0.00±0.58 diopters (D) for dominant eyes and -0.51±0.54 D for non-dominant eyes. Mean binocular UDVA was 0.01±0.10 logMAR (Snellen 20/20) at 6 months and -0.01±0.05 logMAR (Snellen 20/19) at 1 year postoperatively. Mean binocular UNVA was 0.18±0.14 logMAR (Parinaud 2) (Jaeger 1) at 6 months and 0.18±0.12 logMAR (Parinaud 2) (Jaeger 1) at 1 year postoperatively. At 6 months, 79.31% of patients achieved 20/25 and could read Parinaud 2 (Jaeger 1) binocularly. At 1 year, 84.21% of patients achieved 20/25 and could read Parinaud 2 (Jaeger 1) binocularly. The mean central steep zone was 2.35±1.00 D. There were significantly more negative spherical aberration and vertical coma in the central 5 mm postoperatively (P<.05). The re-treatment rate was 6.75%. Eighty-three percent of these patients did not need any glasses for distance and near vision.

CONCLUSIONS

This procedure may improve functional near, intermediate, and distance vision in presbyopic patients with low and moderate hyperopia.

Hydrogel Inlay for Presbyopia: Objective and Subjective Visual Outcomes

PURPOSE

To evaluate changes in visual performance and ocular optical quality after implantation of a corneal hydrogel inlay as a treatment for presbyopia.

METHODS

A Raindrop Near Vision Inlay (ReVision Optics, Lake Forest, CA) was implanted monocularly on the stromal bed of a femtosecond laser-assisted generated corneal flap of non-dominant eyes of 22 patients with emmetropic presbyopia (preoperative spherical equivalent range: -0.50 to 1.00 diopters). Efficacy was determined by measuring near and distance visual acuities and ocular aberrations, and satisfaction was assessed by a patient questionnaire.

RESULTS

The preoperative monocular uncorrected near visual acuity of the inlay inserted eye was 20/129 ± 1 Snellen (range: 20/135 to 20/61 Snellen) and improved to 20/35 ± 2 Snellen (range: 20/61 to 20/20 Snellen) (P < .01) at 6 months postoperatively. The monocular uncorrected distance visual acuity of the eye receiving the inlay was 20/25 ± 2 Snellen (range: 20/50 to 20/20 Snellen) preoperatively and 20/25 ± 1 Snellen (range: 20/50 to 20/20 Snellen) at 6 months postoperatively (P =.257). According to the questionnaire responses, 82% of patients were satisfied. This was despite near glasses needs remaining in 13.6% of the cohort and the presence of glare and a decrease in night vision in approximately 40% of patients. The primary spherical aberration coefficient Z4(0) changed from positive to negative values in all patients (P < .01). However, the point spread function showed no significant change.

CONCLUSIONS

Hydrogel corneal inlays improve uncorrected near visual acuity in patients with presbyopia with only moderate effect on visual quality. However, the satisfaction with this therapy was relatively lower in these Korean patients than that reported previously in Western patients.

[Comparison of two different surgical treatments of presbyopia for hyperopic patients over 55 years old: Presbylasik (Supracor) and Prelex (presbyopic lens exchange)]

INTRODUCTION

The management of presbyopic patients is a medical, surgical and economic issue. We wondered which procedure, whether a Presbylasik technique called Regular Supracor or the intraocular surgery of clear lens replacement by a trifocal diffractive lens (presbyopic lens exchange [Prelex]), provided the best results (in visual acuity and satisfaction) for our hyperopic and presbyopic patients between 55 and 70. The aim of this study was to compare the safety and efficacy of the two techniques (at one week and three months) and to assess patients' quality of life.

METHODS

This study is a retrospective monocentric clinical trial conducted between June 2011 and March 2014, on 21 hyperopic presbyopic patients (mean age 60.9 years), in the "hôpital d'instruction des armées-Percy" (Clamart); 13 patients underwent the corneal treatment of Presbylasik (with the Intralase FS60 femtosecond laser [AMO, USA] and the Technolas 217P excimer laser [Technolas Perfect Vision, GmbH] following the Zyoptix Tissue-Saving algorithm adjusted with a nomogram and the Regular Supracor mode), and 8 patients underwent clear lens extraction (Prelex), through bimanual phacoemulsification and implantation of diffractive trifocal intraocular lenses (Finevision Micro F, PhysIOL(*)).

RESULTS

Mean uncorrected binocular distance and near vision visual acuity in the Supracor group were respectively 0.03 (-0.2-0.1) LogMar and 0.23 (0.06-0.36) one week postoperatively and 0.031 (-0.2-0.1) and 0,166 (0.06-0.36) three months postoperatively. In the Prelex group, the mean uncorrected one week binocular VA was 0.025 (0-0.1) for distance vision and 0.165 (0.06-0.18) for near distance and the three months visual acuity was 0 (-0.1-0.1) and 0.105 (0.06-0.18) for distance and near vision. All Prelex patients were spectacle-free at all distances, whereas 4 Supracor patients required spectacles for near vision postoperatively. Seven of 11 patients in the Supracor group and 100% of the Prelex patients were completely satisfied. Both groups experienced halos, but patients reported more halos in the Prelex group (75%). One eye required intraocular lens exchange and four eyes (16.7%) required a new corneal procedure in the Supracor group.

CONCLUSION

Both surgeries are safe and effective modalities in the management of hyperopic and presbyopic patients. However, the Prelex procedure seems to be more appropriate for patients over 55 years of age.

Visual outcomes and patient satisfaction with a rotational asymmetric refractive intraocular lens for emmetropic presbyopia

PURPOSE

To evaluate the efficacy, safety, predictability, and patient satisfaction after refractive lens exchange with a zonal refractive intraocular lens (IOL) with an inferior reading addition in emmetropic patients.

SETTING

Optical Express, London, United Kingdom.

DESIGN

Retrospective case series.

METHODS

Emmetropic presbyopic patients who had implantation of a Lentis Mplus LS-313 MF30 IOL were evaluated. Inclusion criteria were sphere between -0.50 diopter (D) and +1.00 D with no more than 0.75 D of refractive cylinder and an uncorrected distance visual acuity (UDVA) of 6/6 or better in each eye. The main outcome measures were monocular and binocular UDVA, uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), and patient satisfaction. Three months data are presented.

RESULTS

Four hundred forty eyes of 220 patients were evaluated. The mean monocular UDVA changed from -0.04 logMAR ± 0.06 (SD) preoperatively to -0.04 ± 0.11 logMAR postoperatively (P = .39). The mean CDVA was -0.10 ± 0.05 logMAR preoperatively and -0.09 ± 0.06 logMAR postoperatively (P = .06). At 3 months, 99.7% of eyes were within ±1.00 D of emmetropia. The mean UNVA was 0.13 ± 0.14 logMAR monocularly and 0.10 ± 0.12 logMAR binocularly. On the patient satisfaction questionnaire, 91.9% of patients said the refractive procedure improved their lives and 93.5% were willing to recommend it to friends and family. Three patients requested IOL exchange because of severe night-vision phenomena or unsatisfactory quality of vision.

CONCLUSION

Refractive lens exchange with this zonal refractive IOL was safe in emmetropic presbyopic patients.

FINANCIAL DISCLOSURE

Dr. Schallhorn is a consultant to Abbott Medical Optics. No other author has a financial or proprietary interest in any material or method mentioned.

Preloaded refractive-addition corneal inlay to compensate for presbyopia implanted using a femtosecond laser: one-year visual outcomes and safety

PURPOSE

To report the results of the Icolens corneal inlay 12 months after implantation.

SETTING

Department of Refractive Surgery, Mater Private Hospital, Dublin, Ireland.

DESIGN

Prospective case series.

METHODS

The inlay was implanted in the nondominant eye of emmetropic patients through a femtosecond laser-created corneal pocket.

RESULTS

The mean uncorrected near visual acuity (UNVA) in the surgical eye (n = 52) improved from N18/N24 preoperatively to N8 postoperatively (P = .000); all patients had a UNVA of N16 or better and 9 (17%), of N5 or better. The uncorrected distance visual acuity (UDVA) in the surgical eye increased from 0.05 logMAR ± 0.12 (SD) preoperatively to 0.22 ± 0.15 logMAR postoperatively (P = .000). There was a mean loss of 1.67 ± 1.77 lines of UDVA (P = .000). Binocularly, there was a mean gain of 0.48 ± 1.16 lines of UDVA postoperatively (P = .000), with 22 patients (42%) gaining more than 1 line. The mean loss of corrected distance visual acuity postoperatively was 1.78 ± 1.04 lines (P = .000). There was no significant change in corneal topography or endothelial cell count. On the satisfaction survey, 90% of patients reported being happy ("yes" or "rather yes") with the overall procedure in general. Eleven implants were explanted because of minimal improvement in UNVA. No significant adverse events were reported throughout the study.

CONCLUSION

The new refractive-addition corneal inlay effectively corrected presbyopia in emmetropic presbyopic patients.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Surgical compensation of presbyopia with corneal inlays

Presbyopia, the physiological change in near vision that develops with ageing, gradually affects individuals older than 40 years and is a growing cause of visual disability due to ageing demographics of the global population. The routine use of computers and 'smartphones', combined with the affluence of the 'baby boomers' generation has set high standards for near vision correction. Corneal inlays are a relatively new treatment modality that is effective at compensating for presbyopia. The dimensions of these devices vary from 2 to 3.8 mm in diameter and 5 to 32 μm in thickness. They are implanted in the anterior corneal stroma of the non-dominant eye, most commonly, in a femtosecond laser created corneal pocket. They improve near vision by increasing the depth of focus, creating a hyper-prolate region of increased central cornea power or providing a refractive add power. This article reviews the literature on the efficacy and safety of corneal inlays.

Implantable inlay devices for presbyopia: the evidence to date

By 2020, it is estimated that 2.1 billion people will be presbyopic, and the demand for spectacle independence in this group is growing. This review article provides an overview of the three commercially available corneal inlays for the correction of presbyopia. Safety, efficacy, visual outcomes, and complications are analyzed for all three inlays according to published peer-reviewed data.

Two target locations for corneal inlay implantation combined with laser in situ keratomileusis

PURPOSE

To compare the visual acuity outcomes between 2 target locations for corneal inlay implantation with concurrent laser in situ keratomileusis (LASIK) to compensate for presbyopia.

SETTING

Shinagawa LASIK Center, Tokyo, Japan.

DESIGN

Retrospective cohort study.

METHODS

Bilateral LASIK was performed simultaneously with inlay implantation in the nondominant eye. The preoperative and 6-month postoperative uncorrected distance (UDVA) and uncorrected near (UNVA) visual acuities were evaluated. Patients were divided into the following 2 groups based on the pupil center to Purkinje reflex distance (Pp-Pk): small (≤300 μm) and large (>300 μm). Each group was divided into subgroups according to the distance of the inlay center to the Purkinje reflex (I-Pk) or to the midpoint between the pupil center and Purkinje reflex (I-M). The inlay position was classified as 0 to 100 μm, 101 to 200 μm, 201 to 300 μm, and 301 to 400 μm from the Purkinje reflex and from the midpoint.

RESULTS

Of 1008 patients, 992 were available for postoperative follow-up. The UDVA and UNVA improved in both subgroups with all inlay positions (P < .0001). There were no statistically significant differences in UDVA or UNVA within or between the small Pp-Pk group and the large Pp-Pk group (P > .05). The Spearman rank-order correlation showed weak associations between the inlay distance and visual acuity.

CONCLUSION

The amount of inlay decentration had no influence on postoperative visual acuity.

FINANCIAL DISCLOSURE

Dr. Tomita is a consultant to Acufocus, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Morphologic study of the cornea by in vivo confocal microscopy and optical coherence tomography after bifocal refractive corneal inlay implantation

PURPOSE

To evaluate the biocompatibility of the Flexivue Microlens intracorneal inlay based on healing of corneal wounds and analysis of corneal structural features using in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT).

SETTING

Ophthalmology Department, Misericordia e Dolce Hospital, Prato, Italy.

DESIGN

Case series.

METHODS

The intracorneal inlay was inserted in a stromal pocket created in the nondominant eye of emmetropic presbyopic patients using a femtosecond laser. In vivo confocal microscopy and AS-OCT examinations were performed preoperatively and 1, 6, and 12 months postoperatively.

RESULTS

The mean follow-up was 7.6 months. In the early postoperative period, IVCM showed intense cellular activity in the stroma around the inlay, edema, inflammation, and degenerative material deposition but normal regularity after 12 months. Anterior segment OCT showed a regular planar shape of the corneal pocket in all eyes. The mean of the side-cut angles was 30.7 degrees. The mean difference between the measured and planned pocket depth was 9.77 μm. At 1 month, hyperreflective areas beneath the inlay and microfolds were observed in 21 of the 52 eyes. After 12 months, the anterior segment profile was regular and interface pocket reflectivity decreased over time. Six patients had inlay removal postoperatively (3 before 6 months; 3 before 12 months); after removal, IVCM and AS-OCT showed clear corneas without signs of irregularity.

CONCLUSION

In vivo confocal microscopy and AS-OCT analysis showed that the inlay elicited a low-level wound-healing response in its immediate vicinity with no alteration in the corneal structures.

FINANCIAL DISCLOSURE

Dr. M. Fantozzi is a member of the Presbia medical advisory board. No other author has a financial or proprietary interest in any material or method mentioned.

Image quality of grating target in model eye when viewed through a small-aperture corneal inlay

PURPOSE

To evaluate the quality of the image of a grating target placed in a model eye and viewed through a small-aperture corneal inlay.

SETTING

Kyorin Eye Center, Tokyo, Japan.

DESIGN

Experimental study.

METHODS

A Kamra corneal inlay was placed on the anterior surface of a fluid-filled model eye, and a United States Air Force target and a calibrated scale were placed on the inner surface of the model eye. With a flat contact lens or a contact or noncontact wide-angle viewing system, the contrast of the grating images and the field of view through the inlay were compared with those without the inlay.

RESULTS

A blurred dark ring was observed with the flat contact lens and MiniQuad wide-viewing contact lens in the model eye with the inlay. The contrast of the gratings was significantly decreased at 16 cycles/mm (P=.028), 32 cycles/mm (P=.046), and 64 cycles/mm (P=.015). With the Resight noncontact wide-angle viewing system, the field of view was reduced from 62 degrees to 32 degrees when the front lens was at 7.0 mm and slightly reduced from 75 degrees to 62 degrees at 5.0 mm with the inlay.

CONCLUSIONS

The contrast of grating images observed through the inlay was significantly reduced when viewed with the flat contact lens. The field of view through the wide-angle viewing system was also altered. However, the noncontact wide-angle viewing system may be recommended for vitreous surgeries in eyes with the inlay by adjusting the distance of the front lens from the cornea.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Long-term visual outcomes after Crystalens(®) HD intraocular lens implantation

Purpose

Our purpose was to evaluate the long-term visual outcomes after bilateral implantation of Crystalens^® HD (Bausch and Lomb, Inc.) accommodative intraocular lenses.

Methods

In this study, 25 patients (50 eyes) who underwent cataract surgery and bilateral Crystalens HD accommodative intraocular lens implantation were included. The Crystalens HD lens was implanted in the bag in both eyes, without any intra- or postoperative complications. The visual parameters measured before and after surgery were: uncorrected distance visual acuity, corrected distance visual acuity (CDVA) (using the Early Diabetic Retinopathy Study [EDTRS] logMAR charts), uncorrected intermediate visual acuity, and uncorrected near visual acuity using a Birkhäuser reading chart, at a distance of 66 cm and 33 cm for intermediate and near vision, respectively, directly illuminated by a lamp of 60 watts. After surgery, the patients were evaluated at 1, 3, 6, 12, 24, and 36 months.

Results

The mean age was 68.70±7.1 (range: 54 to 83) years. The mean follow-up was 42.72±0.49 (range: 42.33 to 43.27) months. The uncorrected distance visual acuity improved from 0.56±0.41 (range: 0 to 2) preoperatively to 0.19±0.13 (range: 0 to 0.38) (logMAR scale) at the last follow-up visit, and the CDVA improved from 0.17±0.18 (range: 0 to 0.7) preoperatively to 0.05±0.05 (range: −0.02 to 0.22) at the last follow-up visit. No eyes lost lines of CDVA during the follow-up period, while 54% of patients gained one or more lines of CDVA. The uncorrected intermediate and near visual acuity was J2 or better in 71% and 69% of our patients, respectively.

Conclusion

Crystalens HD implantation seems to provide an improvement in visual acuity for far, intermediate, and near distances.

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.

Past and present of corneal refractive surgery: a retrospective study of long-term results after photorefractive keratectomy and a prospective study of refractive lenticule extraction

Surgical correction of refractive errors is becoming increasingly popular. In the 1990s, the excimer laser revolutionized the field of corneal refractive surgery with PRK and LASIK, and lately refractive lenticule extraction (ReLEx) of intracorneal tissue, using only a femtosecond laser, has become possible. Two new procedures were developed, ReLEx flex (FLEX) and ReLEx smile (SMILE). Until this thesis, only a few long-term studies of PRK with a relatively limited number of patients had been published; therefore, this thesis intended to retrospectively evaluate long-term outcomes after PRK for all degrees of myopia for a large number of patients. Furthermore, a prospective contralateral eye study comparing FLEX and SMILE, when treating high to moderate degrees of myopia, had not been performed prior to this study. This was the second aim of this thesis. In the first study, results from 160 PRK patients (289 eyes) were presented. Preoperative spherical equivalent ranged from -1.25 to -20.25 D, with 78% having low myopia (<-6 D). Average follow-up time was 16 years (range 13-19 years), making this the longest published follow-up study on PRK patients. Outcomes from eyes with low myopia were generally superior to outcomes from eyes with high myopia, at final follow-up. Seventy-two percent were within ± 1.00 D of target refraction, as compared to 47% of eyes with high myopia. However, results from a subgroup of unilateral treated PRK patients indicated that refraction at final follow-up was affected by myopic progression. Fifty percent of eyes with low myopia had uncorrected 20/20 distance visual acuity or better, as compared to 22% of eyes with high myopia. Haze did not occur if attempted corrections were <-4 D, and only eyes with high myopia lost two lines or more of CDVA (corrected distance visual acuity). Eighty-one per cent were satisfied or very satisfied with their surgery.

CONCLUSION

The results support the continued use of the excimer laser for corneal surface ablation as a treatment option for correction of low degrees of myopia, and as the treatment of choice for subgroups of refractive patients (thin corneas, etc.). The results also highlight that treatment of higher degrees of myopia with standard PRK should only be done today under special circumstances, due to low refractive predictability, and high risk of corneal haze. Technological advances since then should be taken into account when comparing these results with contemporary techniques. In the second study, 35 patients were randomized to receive FLEX in one eye and SMILE in the other. Preoperative spherical equivalent refraction ranged from -6 to -10 D with low degrees of astigmatism. A total of 34 patients completed the 6 month follow-up period. Refractive and visual outcomes were very similar for the two methods, as well as tear film measurements and changes in corneal biomechanics. Ninety-seven percent were within ± 1.00 D of target refraction, no eyes lost two lines or more of CDVA, and contrast sensitivity was unaffected after both procedures. The changes in higher-order aberrations were also very similar. There were also no differences in tear film parameters 6 months after surgery, although less postoperative foreign body sensation was reported within the first week after surgery in SMILE eyes. Corneal sublayer pachymetry measurements demonstrated equally increased epithelial thickness 6 months after surgery. Contrary to expectations, it was not possible to measure the theoretical biomechanical advantages of a small corneal incision in SMILE as compared to a corneal flap in FLEX. The main differences between FLEX and SMILE were found when the corneal nerves and intraoperative complications were evaluated. Thus, corneal sensitivity was better preserved and corneal nerve morphology was less affected after SMILE, but intraoperative complications occurred more frequently, although without visual sequela. Finally, 97% were satisfied or very satisfied with both their surgeries.

CONCLUSION

The results support the continued use of both FLEX and SMILE for treatment of up to high degrees of myopia. Overall, refractive and visual results for both procedures were good and similar, but from a biological point of view, the less invasive SMILE technique is more attractive, as demonstrated in this study, despite being slightly more surgically demanding than FLEX.

Impact of pupil transmission apodization on presbyopic through-focus visual performance with spherical aberration

PURPOSE

To investigate the impact on through-focus retinal image quality and visual performance of apodizing the pupil's transmission function in combination with extended depth of focus presbyopic corrections, such as spherical aberration (SA).

METHODS

Through-focus retinal image quality was determined theoretically for various magnitudes of pupil transmission apodization and Zernike primary SA (-0.5 to +0.5 μm) for a 4-mm pupil. The impact of pupil transmission apodization was also assessed psychophysically with a vision simulator equipped with a liquid crystal spatial light modulator for controlling pupil transmission. Through-focus visual acuity (VA) was measured with and without apodization in three cyclopleged subjects from distance to near with monochromatic light (550 nm) under two multifocal aberration conditions. Phase plates induced +0.2 and -0.2 μm of SA over a 4-mm artificial pupil. A baseline condition of zero SA was also included for comparison.

RESULTS

The theoretical investigation showed that pupil transmission apodization significantly improved distance image quality in the presence of positive and negative SA. Retinal image quality at all target vergences for negative SA conditions was improved by apodization. Pupil transmission apodization improved through-focus VA by 0.1 to 0.2 logMAR at intermediate and near object distances for the zero and negative SA conditions. In the positive SA condition, apodization degraded VA by approximately 0.1 logMAR at intermediate object distances.

CONCLUSIONS

Pupil transmission apodization had a significant impact on though-focus visual performance. Pupil transmission apodization affects through-focus retinal image quality by diminishing the relative contribution to the retinal image from the peripheral region of the wavefront aberration. Through-focus visual performance in presbyopic eyes with negative SA was improved due to pupil transmission apodization.

Coaxially sighted corneal light reflex versus entrance pupil center centration of moderate to high hyperopic corneal ablations in eyes with small and large angle kappa

PURPOSE

To determine whether centering ablations on the coaxially sighted corneal light reflex (CSCLR) in eyes with large angle kappa leads to poor visual outcomes when compared to patients with eyes with negligible angle kappa that by default would be centered on the entrance pupil. In eyes with no angle kappa, the CSCLR coincides with the entrance pupil center, whereas eyes with large angle kappa possess an offset between the CSCLR and the entrance pupil center.

METHODS

This study was a retrospective case series of consecutive patients treated by hyperopic LASIK using the MEL80 excimer laser (Carl Zeiss Meditec, Jena, Germany). All ablations were centered on the CSCLR using the standard non-wavefront-guided ablation profile. Angle kappa was classified according to pupil offset defined as the distance in the corneal plane between the entrance pupil center and the corneal vertex. Eyes were divided into two discrete groups according to the pupil offset: small angle kappa for pupil offset of 0.25 mm or less (n = 30) and large angle kappa for pupil offset of 0.55 mm or greater (n = 30). Safety, accuracy, cylinder vector analysis, contrast sensitivity, vertex centered corneal aberrations, entrance pupil centered whole eye aberrometry, and night vision disturbances were compared between the two groups.

RESULTS

There were no statistically significant differences in safety, accuracy, induced astigmatism, contrast sensitivity, or night vision disturbances between the two groups. There was also no statistically significant difference between groups for vertex centered corneal aberrations; however, as expected, coma was higher in the large angle kappa group for entrance pupil centered aberrometry because the treatment had been centered on the CSCLR rather than the entrance pupil center.

CONCLUSION

Refractive outcomes of high hyperopic LASIK were not found to be worse for eyes where ablation was centered more than 0.55 mm from the entrance pupil as determined by CSCLR in eyes with large angle kappa. The absence of poor quality visual outcomes in cases, which by entrance pupil centration are considered significantly "decentered," supports the notion that centration relative to the CSCLR may be preferable. This provides evidence that refractive corneal ablation should not be systematically aligned with the entrance pupil center.

Combined hydrogel inlay and laser in situ keratomileusis to compensate for presbyopia in hyperopic patients: one-year safety and efficacy

PURPOSE

To perform a feasibility study of the safety and efficacy of a corneal-contouring inlay with concurrent laser in situ keratomileusis (LASIK) to treat hyperopic presbyopia.

SETTING

Private clinic, Tijuana, Mexico.

DESIGN

Prospective interventional case series.

METHODS

Hyperopic patients received LASIK in both eyes and a corneal inlay under the femtosecond laser flap in the nondominant eye. The inlay is designed to reshape the anterior corneal curvature, creating a near-center multifocal refractive effect. Main safety outcomes were retention of preoperative corrected distance and near visual acuities and reports of adverse events. Efficacy was determined through measurements of near, intermediate, and distance visual acuities and patient questionnaires on visual task ability and satisfaction.

RESULTS

The study enrolled 16 patients. All eyes with an inlay achieved an uncorrected near visual acuity (UNVA) of 20/32 or better by the 1-week postoperative examination and at every visit thereafter. The mean monocular and binocular UNVA was 20/27 or better at all visits. The mean binocular uncorrected distance visual acuity improved significantly from 20/53 preoperatively to 20/19 postoperatively (P<10(-5)). One inlay was explanted during the study. At 1 year, all 14 patients analyzed were satisfied or very satisfied with their near, distance, and overall vision.

CONCLUSIONS

The hydrogel corneal inlay with concurrent LASIK improved uncorrected near, intermediate, and distance visual acuity in hyperopic presbyopic patients with high patient satisfaction and visual task ability. This represents a new indication for this recently developed technology.

Corneal inlays for presbyopia correction

PURPOSE OF REVIEW

This study provides an overview of the three types of corneal inlays now in use for the correction of presbyopia and reviews recently published evidence of the inlays' safety and efficacy.

RECENT FINDINGS

Results for corneal reshaping and refractive inlays are promising, but very limited. Small-aperture inlays are already in widespread use and have been shown to improve uncorrected near and intermediate vision without a significant loss in distance acuity or an unacceptable increase in visual symptoms. Complications have been minimal, but the inlays may be removed if necessary. They do not prevent visualization or imaging of the retina and may be retained during subsequent cataract surgery.

SUMMARY

The presbyopic demographic is large and growing, with a high level of interest in spectacle independence. There is currently no other effective solutions for presbyopes who desire good uncorrected vision at all distances without the risks of intraocular surgery or the visual compromises of monovision. Additional research is needed, but the future for corneal inlay technology is bright.

[Annular keratopigmentation (PresbyRing®) for treating presbyopia: postmortem animal feasibility study]

INTRODUCTION

Annular keratopigmentation (PresbyRing(®)) is a new technique which creates an intrastromal ring centered on the visual axis, using a femtosecond laser, into which a black or a colored pigment is then injected. The internal diameter of the ring is dimensioned so as to create a pinhole and improve the near and intermediate vision of the non-dominant eye while only slightly altering the distance vision of that eye.

MATERIAL AND METHODS

We used five pig eyes for our postmortem feasibility study; all five were treated with the Intra Corneal Ring program (ICR(®)) of the Visumax(®) laser. The dye used (Biochromaderm(®)) has EU approval.

RESULTS

Spectral domain OCT examinations demonstrate complete opacity of the dye. Histological analysis with hematoxylin and eosin stain highlights a continuous pigmented layer located along the incision, which does not diffuse in the adjacent stroma. The possibility of rinsing the dye must be confirmed by future in-vivo animal studies.

CONCLUSION

To our knowledge, this study represents the first experimental attempt to combine two ideas which did not appear to have anything in common: the creation of an intracorneal pinhole to treat presbyopia, and corneal tattooing. The first postmortem feasibility study in animals for annular keratopigmentation (PresbyRing(®)) gave encouraging results. It must be confirmed by in vivo animal studies, and ultimately in humans.

Visual outcomes and safety of a refractive corneal inlay for presbyopia using femtosecond laser

PURPOSE

To evaluate the outcomes and safety of a refractive inlay (Flexivue Micro-Lens, Presbia Coöperatief U.A.) for the corneal compensation of presbyopia.

METHODS

This prospective, interventional clinical study comprised 47 emmetropic presbyopes with a mean age of 52±4 years (range: 45 to 60 years). The inlay was inserted, centered on the line of sight, inside a corneal pocket created in the patient's nondominant eye, using a femtosecond laser. Follow-up was 12 months. Visual acuity, corneal topography, wavefront aberrometry, contrast sensitivity, structural corneal alterations, and questionnaires were evaluated.

RESULTS

Twelve months after surgery, uncorrected near visual acuity was 20/32 or better in 75% of operated eyes, whereas mean uncorrected distance visual acuity (UDVA) of operated eyes was statistically significantly decreased from 0.06±0.09 logMAR (20/20) (range: -0.08 to 0.26) preoperatively to 0.38±0.15 logMAR (20/50) (range: 0.12 to 0.8) (P<.001), and mean binocular UDVA was not significantly altered (P=.516). Seventeen patients lost one line of corrected distance visual acuity in the operated eye. No patient lost 2 lines in CDVA in the operated eye. Overall, higher order aberrations increased and contrast sensitivity decreased in the operated eye. No tissue alterations were found using corneal confocal microscopy. No intra- or postoperative complications occurred.

CONCLUSIONS

Twelve months after implantation, the Flexivue Micro-Lens intracorneal refractive inlay seems to be an effective method for the corneal compensation of presbyopia in emmetropic presbyopes aged between 45 and 60 years old.

Femtosecond laser technology in corneal refractive surgery: a review

PURPOSE

To discuss current applications and advantages of femtosecond laser technology over traditional manual techniques and related unique complications in corneal refractive surgical procedures, including LASIK flap creation, intracorneal ring segment implantation, astigmatic keratotomy, presbyopic treatments, and intrastromal lenticule procedures.

METHODS

Literature review.

RESULTS

From its first clinical use in 2001 for LASIK flap creation, femtosecond lasers have steadily made a place as the dominant flap-making technology worldwide. Newer applications are being evaluated and are increasing in their frequency of use.

CONCLUSIONS

Femtosecond laser technology is rapidly becoming a heavily utilized tool in corneal refractive surgical procedures due to its reproducibility, safety, precision, and versatility.

LASIK for presbyopia correction in emmetropic patients using aspheric ablation profiles and a micro-monovision protocol with the Carl Zeiss Meditec MEL 80 and VisuMax

PURPOSE

To evaluate the monocular and binocular visual outcomes of LASIK with an aspheric micro-mono-vision protocol in emmetropic patients with presbyopia.

METHODS

A retrospective, noncomparative case series included 296 eyes from 148 consecutive emmetropic patients with presbyopia who were treated with LASIK-induced micro-monovision. The CRS-Master software was used to generate ablation profiles for the MEL 80 excimer laser (Carl Zeiss Meditec) and flaps were created using the VisuMax femtosecond laser (Carl Zeiss Meditec). The target refraction was plano for distance eyes (dominant eye) and between -1.00 and -1.88 diopters (D) for near eyes. Patients were followed for 1 year. Emmetropia was defined for inclusion as spherical equivalent refraction ⩾- 0.88 D, sphere ⩽+1.00 D, and cylinder ⩽1.25 D. Median patient age was 55 years (range: 44 to 65 years). Median follow-up was 12.9 months.

RESULTS

Mean deviation from intended correction was +0.02±0.35 D, with 91% within ±0.50 D and 100% within ±1.00 D. Of distance eyes, 95% achieved uncorrected distance visual acuity (UDVA) of 20/20 or better and 100% achieved 20/32 or better. Binocularly, 98% of patients achieved UDVA of 20/20 or better and 100% achieved 20/32 or better; 96% achieved uncorrected near visual acuity of J2 and 99% could read J3 or better. No eyes lost 2 or more lines of corrected distance visual acuity. An average increase of 0.05 logMAR was noted in distance-corrected near visual acuity. A small increase occurred in mesopic contrast sensitivity (CSV-1000, VectorVision Inc) at 3 cycles per degree (cpd) (P=.016) and no change at 6, 12, or 18 cpd.

CONCLUSIONS

This aspheric micro-monovision protocol was a well-tolerated and effective procedure for treating emmetropic patients with presbyopia.