Simultaneous corneal inlay implantation and laser in situ keratomileusis for presbyopia in patients with hyperopia, myopia, or emmetropia: six-month results

Complications of Small Aperture Intracorneal Inlays: A Literature Review

Presbyopia can be defined as the refractive state of the eye in which, due to a physiological decrease in the ability to accommodate, it is not possible to sustain vision without fatigue in a prolonged manner, along with difficulty focusing near vision. It is estimated that its prevalence in 2030 will be approximately 2.1 billion people. Corneal inlays are an alternative in the correction of presbyopia. They are implanted beneath a laser-assisted in situ keratomileusis (LASIK) flap or in a pocket in the center of the cornea of the non-dominant eye. The purpose of this review is to provide information about intraoperative and postoperative KAMRA inlay complications in the available scientific literature. A search was conducted on PubMed, Web of Science, and Scopus with the following search strategy: ("KAMRA inlay" OR "KAMRA" OR "corneal inlay pinhole" OR "pinhole effect intracorneal" OR "SAICI" OR "small aperture intracorneal inlay") AND ("complication" OR "explantation" OR "explanted" OR "retired"). The bibliography consulted shows that the insertion of a KAMRA inlay is an effective procedure that improves near vision with a slight decrease in distance vision. However, postoperative complications such as corneal fibrosis, epithelial iron deposits, and stromal haze are described.

Review of surgical devices using small aperture optics

Small aperture optics work by blocking unfocused peripheral light rays while allowing central light rays to focus on the retina. This pinhole effect creates an extended depth of focus and has been used in presbyopia correction, improving intermediate and near vision without markedly affecting distance vision. Another beneficial effect of small aperture optics is reducing aberrations caused by irregular corneas or irregular pupils. The first small aperture surgical device was the Kamra corneal inlay used on the nondominant eyes of presbyopic emmetropes. The pinhole concept was also adapted into the IC-8 intraocular lens (IOL) for presbyopia correction during cataract surgery and by the XtraFocus piggyback device to lessen unwanted aberrations in eyes with irregular corneas or pupils. The IC-8 IOL can be placed monocularly or binocularly with mini-monovision for further near vision improvement. The XtraFocus piggyback device can be placed either in the sulcus or capsular bag. The aim of this literature review is to synthesize evidence on the efficacy, safety, and patient-reported outcomes on surgical devices utilizing small aperture optics. A comprehensive search on PubMed was conducted with the keywords “small aperture optics,” “small aperture corneal inlay,” “small aperture IOL,” “Kamra corneal inlay,” “IC-8 IOL,” and “XtraFocus.” In this review, we describe the progression of small aperture surgical devices, patient criteria, visual outcomes, complications, satisfaction, and recommendations for surgical success.

Advances in Corneal Surgical and Pharmacological Approaches to the Treatment of Presbyopia

The purpose of this article is to review the current status of presbyopia amelioration with surgical and pharmacologic procedures that partially compensate for loss of accommodation in advance of cataract surgery and lens replacement. Over the last few years, several corneal surgical and topical pharmacological approaches for the treatment of presbyopia have been introduced to the marketplace or are in the developmental pipeline. The approaches vary in invasiveness, duration of effect, reversibility, risk/benefit ratio, and clinical results. The advantages and disadvantages for each are discussed. Corneal surgical interventions aim to provide improved near and intermediate vision in patients with presbyopia through refractive means that extend ocular depth of focus through shape modification. The use of miotic drops or corneal lamellar implants extend depth of focus with the "pinhole" aperture size reduction effect. Unlike in adults younger than 40 years, the refractive status of the patient with presbyopia is not stable. Hence, procedures that provide a permanent refractive change may not provide long-term full correction; eye drops or other treatments that are self-reversing in time or are easily reversible may be used as needed. On the horizon, procedures are being explored that may add years of functional lens accommodation by preserving the deformable gel properties of the lens. [J Refract Surg. 2021;37(6 Suppl):S20-S27.].

Corneal Stromal Filler Injection as a Novel Approach to Correct Presbyopia-An Ex Vivo Pilot Study

Purpose

To evaluate the ex vivo feasibility of corneal stromal filler injection to create bifocality to correct presbyopia by flattening the central posterior corneal surface and thus increase refractive power.

Methods

Femtosecond laser-assisted corneal stromal pockets of varying diameters close to the posterior corneal curvature were cut into rabbit eyes ex vivo. Subsequently, hyaluronic acid was injected to flatten the central posterior curvature. Refractive parameters were determined using perioperatively acquired three-dimensional optical coherence tomography (OCT) scans. Using micrometer-resolution OCT, corneal endothelial cell morphology and density were evaluated.

Results

Following filler injection into the corneal stromal pockets, a fair volume-dependent increase of central refractive power up to 4 diopters (dpt) was observed. Unremarkable refractive changes of the peripheral posterior (3 mm, 0.20 ± 0.11 dpt; 2 mm, 0.11 ± 0.10 dpt) and the anterior corneal curvature (3 mm, 0.20 ± 0.34 dpt; 2 mm, 0.33 ± 0.31 dpt) occurred. Only negligible changes in astigmatism were observed. Different sizes of optical zones could be established. Furthermore, no alterations of corneal endothelial morphology or endothelial cell density (2831 ± 356 cells/mm² vs. 2734 ± 292 cells/mm²; P = 0.552) due to the adjacent laser treatment were observed.

Conclusions

The ex vivo investigations proved the principle of injecting a filler material into femtosecond laser-created corneal stromal pockets close to the posterior corneal curvature as an efficacious, individually adjustable, and novel approach to correct presbyopia without ablating corneal tissue.

Translational Relevance

Due to the aging population worldwide, presbyopia is an increasing problem; thus, our study may encourage further exploration to extend the treatment spectrum of clinically used femtosecond laser systems to correct presbyopia.

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.

KAMRA Inlay Implantation for Presbyopia Compensation: A Retrospective Evaluation of Patient Satisfaction and Subjective Vision 12-Month Postoperative

PURPOSE:

The aim of the study is to evaluate patients' satisfaction and subjective vision 12 months after monocular KAMRA corneal inlay implantation for the surgical compensation of presbyopia.

SUBJECTS AND METHODS:

Medical records of patients who underwent corneal inlay implantation in the nondominant eye between 2013 and 2014 were retrospectively reviewed. Data were collected from several centers in Lebanon. Patients with hyperopia or myopia with presbyopia between 45 and 70 years not suffering from any other ocular pathology were eligible for inclusion. Twelve-month postoperative satisfaction score was evaluated in all patients as well as the subjective vision score for near, intermediate, and distant tasks.

RESULTS:

This study included 73 patients. Almost 95% (69/73) of patients were satisfied or very satisfied with their vision and 93% (68/73) never or almost never used reading glasses while performing daily tasks. Subjective vision scores were found to be higher for distant and intermediate tasks performed during the day than for those performed during the night (P < 0.001). The average subjective vision score for reading a book or a newspaper in dim light was the lowest among all average subjective vision scores. No difference in satisfaction was found between patients with myopia or hyperopia or between males and females.

CONCLUSION:

The implant of a small-aperture corneal inlay resulted in a substantial improvement in patients' distant, intermediate, and near subjective vision, better in normal light than in dim light, and most patients became spectacles independent.

Presbyopia management with Q-factor modulation without additive monovision: One-year visual and refractive results

PURPOSE

To analyze refractive results after hyperopic presbyopia surgery by Q-factor modulation without additive monovision.

SETTING

Quinze-Vingts National Ophthalmology Hospital, Paris, France.

DESIGN

Prospective nonrandomized study.

METHODS

Forty-five hyperopic presbyopic patients not tolerating monovision were included. The target for the dominant eye was emmetropia, whereas that for the nondominant eye was emmetropia associated with a target Q factor of -0.8. The postoperative follow-up included assessments of spherical equivalent (SE) refraction, monocular and binocular corrected and uncorrected (UDVA) distance visual acuities, and binocular corrected and uncorrected (UNVA) near visual acuities. Corneal pachymetry, topography, aberrometry and an analysis of patient satisfaction were performed at the 12-month examination.

RESULTS

The study comprised 90 eyes of 45 consecutive patients. The mean age at surgery was 53.8 years ± 4.99 (SD). The mean preoperative SE was +2.33 ± 1.16 diopters (D) in the dominant eyes and +2.26 ± 1.17 D in the nondominant eyes. At 12 months postoperatively, 42 patients (93%) had a binocular UDVA of Snellen 20/20 and 37 patients (82%) had a binocular UNVA of Jaeger 2 (Parinaud 3). The mean SE at 12 months was -0.22 ± 0.35 D in the dominant eyes (P < .0001) and -0.83 ± 0.50 D in the nondominant eyes (P < .0001). Two eyes required retreatment. Overall, 39 patients (87%) said that they were satisfied and would recommend the intervention.

CONCLUSION

The Q-factor modulation without additive monovision aims to compensate for presbyopia by changing the Q factor of the nondominant eye to generate a greater depth of field in hyperopic presbyopic patients who are unable to tolerate monovision. The visual outcomes and quality of vision were satisfactory, and only a few patients required additional correction.

Monovision LASIK in emmetropic presbyopic patients

Background

To evaluate the efficacy and patient satisfaction of laser in situ keratomileusis (LASIK) monovision correction in presbyopic emmetropic patients.

Methods

A retrospective review of 294 patients who underwent LASIK for monovision was conducted. All patients had preoperative uncorrected distance visual acuity in each eye of 20/25 or better in both eyes and underwent primary LASIK treatment in one eye with a near target; 82 patients underwent surgery in the distant eye for hypermetropia. Patients completed a patient-reported-outcome questionnaire at their one-month postoperative visit. Analysis was performed on a per patient basis with a logistic regression model.

Results

Patients achieved a postoperative mean spherical equivalent of -0.05 diopters (D) in the distant eye and -1.92 D in the near eye. Prior to surgery, 64.7% (n=178) of patients reported they were satisfied or very satisfied with their vision; postoperatively, this increased to 85.4% (n=251). The greatest predictor of dissatisfaction after surgery was severe patient-reported visual phenomena (glare, halos, starbursts, ghosting) (odds ratio 1.18, P=0.001).

Conclusions

LASIK monovision for presbyopic patients with low refractive error and good preoperative uncorrected distance visual acuity is both safe and effective with high patient satisfaction. Patients who were dissatisfied in the postoperative period tended to be those with postoperative visual symptoms.

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.

Correction of presbyopia: An integrated update for the practical surgeon

Presbyopia results from loss or insufficiency of the eye's accommodative ability, and clinically manifests as the inability to focus near objects on the retina. It is one of the most common causes of visual impairment worldwide especially in adults of productive or working age. Various means of compensating for the loss of accommodative ability have been devised from optical tools such as spectacles and contact lenses, to topical medications and to surgical procedures. A comprehensive search on journal articles about topical and surgical correction of presbyopia was undertaken. The various techniques for presbyopia correction, as enumerated in these articles, are discussed in this paper with the addition of our personal experience and perspective on the future of these techniques.

Review of Static Approaches to Surgical Correction of Presbyopia

Presbyopia is the primary cause of reduction in the quality of life of people in their 40s, due to dependence on spectacles. Therefore, presbyopia correction has become an evolving and rapidly progressive field in refractive surgery. There are two primary options for presbyopia correction: the dynamic approach uses the residual accommodative capacity of the eye, and the static approach attempts to enhance the depth of focus of the optical system. The dynamic approach attempts to reverse suspected pathophysiologic changes. Dynamic approaches such as accommodative intraocular lenses (IOLs), scleral expansion techniques, refilling, and photodisruption of the crystalline lens have attracted less clinical interest due to inconsistent results and the complexity of the techniques. We have reviewed the most popular static techniques in presbyopia surgery, including multifocal IOLs, PresbyLASIK, and corneal inlays, but we should emphasize that these techniques are very different from the physiologic status of an untouched eye. A systematic PubMed search for the keywords “presbylasik”, “multifocal IOL”, and “presbyopic corneal inlay” revealed 634 articles; 124 were controlled clinical trials, 95 were published in the previous 10 years, and 78 were English with available full text. We reviewed the abstracts and rejected the unrelated articles; other references were included as needed. This narrative review compares different treatments according to available information on the optical basis of each treatment modality, including the clinical outcomes such as near, intermediate, and far visual acuity, spectacles independence, quality of vision, and dysphotopic phenomena.

A Multicenter Retrospective Survey of Refractive Surgery in 78,248 Eyes

PURPOSE

To retrospectively evaluate the current practice, trends, and outcomes of refractive surgery in Japan.

METHODS

This multicenter survey comprised 78,248 eyes of 39,727 consecutive patients who underwent refractive surgery at 45 major institutions in Japan. The corresponding ophthalmologists responded to a selfadministered questionnaire. The authors especially evaluated the safety, efficacy, predictability, stability, and adverse events of LASIK and phakic intraocular lens (IOL) implantation 3 months postoperatively.

RESULTS

The most common refractive surgery was LASIK (90.9%), followed by corneal inlay (5.0%), posterior chamber phakic IOL implantation (1.3%), laser-assisted subepithelial keratomileusis (1.0%), refractive lens exchange (0.9%), photorefractive keratectomy (0.3%), and refractive lenticule extraction (0.2%). For subgroup analysis, 69,987 eyes (99.5%) and 67,512 eyes (95.9%) achieved corrected and uncorrected distance visual acuity of 20/20 or better, respectively, after LASIK, and 935 eyes (98.8%) and 890 eyes (94.1%), respectively, after phakic IOL implantation. There were 69,176 eyes (98.3%) and 908 eyes (96.0%) within ±1.00 diopter (D) of the attempted correction after LASIK and phakic IOL implantation, respectively. There were 1,926 eyes (2.7%) and 1 eye (0.1%) with changes in refraction of 1.00 D or less from 1 week to 3 months after LASIK and phakic IOL implantation, respectively. No vision-threatening complications occurred in any case.

CONCLUSIONS

According to this survey, LASIK remains the most prevalent surgical technique in Japan. Both LASIK and phakic IOL implantation offered good safety and efficacy outcomes, yielding predictable and stable results. [J Refract Surg. 2017;33(9):598-602.].

Long-term Results of Combined LASIK and Monocular Small-Aperture Corneal Inlay Implantation

PURPOSE

To evaluate the long-term effectiveness and safety of combined LASIK and small-aperture intracorneal inlay implantation (KAMRA; AcuFocus, Irvine, CA) for the surgical compensation of presbyopia and refractive errors.

METHODS

Retrospective chart review of all ametropic, presbyopic patients who underwent combined LASIK and KAMRA inlay implantation at a single clinic. Demographic data and preoperative uncorrected and corrected monocular and binocular near and distance visual acuity (UNVA, UDVA, and CDVA) with manifest refractive spherical equivalent (MRSE) were collected and analyzed. All perioperative adverse events were recorded.

RESULTS

In total, 132 patients were available (median age: 56 years; interquartile range (IQR) ± 5; range: 44 to 68 years). Median preoperative MRSE was +1.37± 1.20 diopters (D). The majority (113; 85%) were hypermetropic. Preoperative median UNVA improved from N24 (J13) ±6 to N6 (J5) ±1 by day 1 postoperatively, remaining stable throughout follow-up. At last follow-up, 97% of patients achieved UNVA of N5 (J3) or better. Median UDVA (implanted eye) improved from 20/40 (0.50 ± 0.41 on the decimal chart) preoperatively to 20/25 (0.80 ± 0.13) at month 12. Binocular UDVA was 20/20 in 88%, with CDVA unchanged for 84% at 12 months. No patient lost more than one line of CDVA. MRSE was also stable, albeit +0.25 D off-target refraction (-0.75 D). Two inlays were explanted due to suboptimal adaptation/corneal haze.

CONCLUSIONS

The results of this follow-up study show that combined insertion of a small-aperture corneal inlay with LASIK in presbyopic patients improves near vision with a slight compromise in distance vision in the implanted eye. Overall, it appears to be a safe, effective procedure for the treatment of presbyopia. [J Refract Surg. 2016;32(6):379-384.].

TFOS DEWS II iatrogenic report

Dry eye can be caused by a variety of iatrogenic interventions. The increasing number of patients looking for eye care or cosmetic procedures involving the eyes, together with a better understanding of the pathophysiological mechanisms of dry eye disease (DED), have led to the need for a specific report about iatrogenic dry eye within the TFOS DEWS II. Topical medications can cause DED due to their allergic, toxic and immuno-inflammatory effects on the ocular surface. Preservatives, such as benzalkonium chloride, may further aggravate DED. A variety of systemic drugs can also induce DED secondary to multiple mechanisms. Moreover, the use of contact lens induces or is associated with DED. However, one of the most emblematic situations is DED caused by surgical procedures such as corneal refractive surgery as in laser-assisted in situ keratomileusis (LASIK) and keratoplasty due to mechanisms intrinsic to the procedure (i.e. corneal nerve cutting) or even by the use of postoperative topical drugs. Cataract surgery, lid surgeries, botulinum toxin application and cosmetic procedures are also considered risk factors to iatrogenic DED, which can cause patient dissatisfaction, visual disturbance and poor surgical outcomes. This report also presents future directions to address iatrogenic DED, including the need for more in-depth epidemiological studies about the risk factors, development of less toxic medications and preservatives, as well as new techniques for less invasive eye surgeries. Novel research into detection of early dry eye prior to surgeries, efforts to establish appropriate therapeutics and a greater attempt to regulate and oversee medications, preservatives and procedures should be considered.

Non-lens-based surgical techniques for presbyopia correction

INTRODUCTION

Presbyopia is the most prevalent refractive error. With a progressive aging population, its surgical correction is an important challenge for the ophthalmology community, as well as the millions of patients who suffer from it, and who are increasingly demanding alternatives to its correction with glasses or contact lenses.

MATERIAL AND METHODS

A review is presented with a synthesised discussion on the pathophysiological theories of presbyopia and an updated and analytical description of the non-lens involvement surgical techniques used to treat presbyopia.

RESULTS

Corneal procedures include various types of corneal implants and photo-ablative techniques that generate a multifocal cornea, or monovision. Scleral procedures exert a traction on supralenticular sclera that supposedly would improve the amplitude of accommodation.

CONCLUSIONS

None of the techniques are able to completely eliminate the need for near -vision glasses, but many of them manage to improve the refractive status of the patients. More studies with rigorous and standardised methods and longer follow-up are needed to evaluate the changes in the near vision of the patients, in order to corroborate the real and practical usefulness of many of these techniques.

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.

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.

Six-month visual outcomes for the correction of presbyopia using a small-aperture corneal inlay: single-site experience

Objective

The objective of this study was to describe 6-month postoperative efficacy and safety outcomes after monocular KAMRA corneal inlay implantation in emmetropic presbyopic patients.

Study design

This study followed a retrospective chart analysis.

Setting

This study was performed at Hoopes Vision in Draper, UT, USA.

Subjects and methods

Fifty-seven patients met the inclusion criteria of this study and underwent KAMRA corneal inlay implantation following the approval of the United States Food and Drug Association between May 2015 and April 2016 at a single site. Surgery involved femtosecond laser-created corneal pockets of various depths. Efficacy, safety, and patient satisfaction reports were analyzed at 3 and 6 months.

Results

At 6 months follow-up, the monocular uncorrected near visual acuity (UNVA) was Jaeger (J) 4 (20/32), the mean uncorrected distance visual acuity was 20/25, and the mean corrected distance visual acuity was 20/20. At 6 months, 71% of patients with a pocket depth of ≥250 μm had a UNVA of 20/20 or better, whereas only 22% of patients with a shallow pocket depth of <250 μm had a UNVA of 20/20 or better. There was no statistical difference in UNVA at 6 months between virgin eyes and post-LASIK eyes. One patient had an explant and five patients underwent inlay recentration, all of which resulted in improved visual acuity. At 6 months, 72% of patients reported some level of satisfaction, 26% of patients reported being “not dependent” on reading glasses, and 62% of patients reported being able to do most things in bright light without reading glasses.

Conclusion

For patients with emmetropic presbyopia, the KAMRA inlay is a viable treatment option resulting in improved UNVA. Increased pocket depth may be associated with better postoperative outcomes. Safety rates are high, while explantation and recentering rates are low. Overall, patient satisfaction of the KAMRA inlay is good.

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.

Clinical utility of the KAMRA corneal inlay

The treatment of presbyopia has been the focus of much scientific and clinical research over recent years, not least due to an increasingly aging population but also the desire for spectacle independence. Many lens and nonlens-based approaches have been investigated, and with advances in biomaterials and improved surgical methods, removable corneal inlays have been developed. One such development is the KAMRA™ inlay where a small entrance pupil is exploited to create a pinhole-type effect that increases the depth of focus and enables improvement in near visual acuity. Short- and long-term clinical studies have all reported significant improvement in near and intermediate vision compared to preoperative measures following monocular implantation (nondominant eye), with a large proportion of patients achieving Jaeger (J) 2 to J1 (~0.00 logMAR to ~0.10 logMAR) at the final follow-up. Although distance acuity is reduced slightly in the treated eye, binocular visual acuity and function remain very good (mean 0.10 logMAR or better). The safety of the inlay is well established and easily removable, and although some patients have developed corneal changes, these are clinically insignificant and the incidence appears to reduce markedly with advancements in KAMRA design, implantation technique, and femtosecond laser technology. This review aims to summarize the currently published peer-reviewed studies on the safety and efficacy of the KAMRA inlay and discusses the surgical and clinical outcomes with respect to the patient’s visual function.

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.

Dry Eye Syndrome Risks in Patients With Fibromyalgia: A National Retrospective Cohort Study

The coexistence of fibromyalgia (FM) and dry eye syndrome (DES) has been previously reported. However, there are few studies on how patients with FM may develop concomitant DES. Patients with chronic widespread pain, like FM, chronic fatigue syndrome, and irritable bowel syndrome (IBS), was concerned for the rheumatic or psychosomatic disorders which might adequately reflect the long-term risk of DES. We retrieved data on FM patients from the National Health Insurance Research Database of Taiwan covering the years 2000 to 2011. Our FM population consisted of 25,777 patients versus 103,108 patients in the non-FM group: the overall incidence of DES in these populations was 7.37/10,000 and 4.81/10,000, respectively. Male FM patients had a higher incidence of DES, with a 1.39-fold DES risk for males and a 1.45-fold for females after adjustment for confounding factor. Notably, FM patients aged ≤49 years had an elevated 80% risk of DES compared with the non-FM group. Without comorbidities, FM patients had an approximately 1.40-fold risk of DES than those without FM. The additive effects of FM and IBS or FM and sleep disturbance were pointed out that the risk for DES would be elevated when the FM patients with IBS or sleep disturbance. FM patients have a higher incidence of DES than that of non-FM patients. They carry long-term DES risks from a relatively young age, particularly those with psychiatric problems. Risk stratification for a timely psychiatric medication intervention and risk modifications are not intended.

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.

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.

The evolution of corneal and refractive surgery with the femtosecond laser

The use of femtosecond lasers has created an evolution in modern corneal and refractive surgery. With accuracy, safety, and repeatability, eye surgeons can utilize the femtosecond laser in almost all anterior refractive procedures; laser in situ keratomileusis (LASIK), small incision lenticule extraction (SMILE), penetrating keratoplasty (PKP), insertion of intracorneal ring segments, anterior and posterior lamellar keratoplasty (Deep anterior lamellar keratoplasty (DALK) and Descemet's stripping endothelial keratoplasty (DSEK)), insertion of corneal inlays and cataract surgery. As the technology matures, it will push surgical limits and open new avenues for ophthalmic intervention in areas not yet explored. As we witness the transition from femto-LASIK to femto-cataract surgery it becomes obvious that this innovation is here to stay. This article presents some of the most relevant advances of femtosecond lasers to modern corneal and refractive surgery.

Corneal inlay implantation complicated by infectious keratitis

BACKGROUND/AIMS

To report five cases of infectious keratitis following corneal inlay implantation for the surgical correction of presbyopia.

METHODS

This was a retrospective, observational case series. Five eyes of five patients were identified consecutively in two emergency departments during a 1-year period, from November 2013 to November 2014. Patients' demographics, clinical features, treatment and outcomes are described.

RESULTS

There were four female patients and one male, aged 52-64 years. Three patients had the KAMRA inlay (AcuFocus) and two had the Flexivue Microlens inlay (Presbia Coöperatief U.A.) inserted for the treatment of presbyopia and they presented from 6 days to 4 months postoperatively. Presenting uncorrected vision ranged from 6/38 to counting fingers. One patient's corneal scrapings were positive for a putatively causative organism, Corynebacterium pseudodiphtheriticum, and all patients responded to broad-spectrum fortified topical antibiotics. All patients lost vision with final uncorrected visual acuity ranging from 6/12 to 6/60 and best-corrected vision ranging from 6/7.5 to 6/12. Two patients' corneal inlays were explanted and three remained in situ at last follow-up.

CONCLUSIONS

Infectious keratitis can occur at an early or late stage following corneal inlay implantation. Final visual acuity can be limited by stromal scarring; in the cases where the infiltrate was small and off the visual axis at the time of presentation, the final visual acuity was better than those patients who presented with larger lesions affecting the visual axis. Though infection may necessitate removal of the inlay, early positive response to treatment may enable the inlay to be left in situ.

A review of the surgical options for the correction of presbyopia

Presbyopia is an age-related eye condition where one of the signs is the reduction in the amplitude of accommodation, resulting in the loss of ability to change the eye's focus from far to near. It is the most common age-related ailments affecting everyone around their mid-40s. Methods for the correction of presbyopia include contact lens and spectacle options but the surgical correction of presbyopia still remains a significant challenge for refractive surgeons. Surgical strategies for dealing with presbyopia may be extraocular (corneal or scleral) or intraocular (removal and replacement of the crystalline lens or some type of treatment on the crystalline lens itself). There are however a number of limitations and considerations that have limited the widespread acceptance of surgical correction of presbyopia. Each surgical strategy presents its own unique set of advantages and disadvantages. For example, lens removal and replacement with an intraocular lens may not be preferable in a young patient with presbyopia without a refractive error. Similarly treatment on the crystalline lens may not be a suitable choice for a patient with early signs of cataract. This article is a review of the options available and those that are in development stages and are likely to be available in the near future for the surgical correction of presbyopia.

Long-term outcomes after monocular corneal inlay implantation for the surgical compensation of presbyopia

PURPOSE

To evaluate long-term outcomes of small-aperture corneal inlay implantation for the surgical compensation of presbyopia.

SETTING

Paracelsus Medical University, Salzburg, Austria.

DESIGN

Prospective interventional cohort study.

METHODS

Monocular implantation of a Kamra small-aperture inlay (model ACI7000) (1.6 mm central aperture) was performed in emmetropic presbyopic eyes. The preoperative and postoperative parameters included monocular and binocular uncorrected (UDVA) and corrected (CDVA) distance visual acuities, uncorrected intermediate visual acuity (UIVA), and uncorrected (UNVA) and corrected (CNVA) near visual acuities; refraction; patient satisfaction; and complications.

RESULTS

From September 4, 2006, to May 21, 2007, a small-aperture inlay (1.6 mm central aperture) was implanted in 32 emmetropic presbyopic eyes. The mean binocular uncorrected visual acuities improved as follows: UNVA from Jaeger (J) 6 ± 1.2 lines (∼20/50) to J2 ± 1.8 lines (∼20/25) (P < .001) and UIVA from 0.2 logMAR ± 1.3 lines (∼20/32) to 0.1 logMAR ± 1.3 lines (∼20/25) (P = .04). The UDVA decreased from -0.2 logMAR ± 0.2 lines (∼20/12.5) to -0.1 logMAR ± 0.6 lines (∼20/16) (P < .001). At 60 months, 74.2% of patients had a UNVA of J3 (∼20/32) or better, 87.1% had a UIVA of 0.2 logMAR (∼20/32) or better, and 93.5% had a UDVA of 0.0 logMAR (∼20/20) or better. One inlay was removed after 36 months because of patient dissatisfaction with vision after a hyperopic shift in the surgical eye, with no loss of CDVA or CNVA 2 years after removal.

CONCLUSION

Long-term results of monocular corneal inlay implantation indicate increased UNVA and UIVA and slightly compromised UDVA in emmetropic presbyopic eyes.

FINANCIAL DISCLOSURE

Dr. Grabner was reimbursed for travel expenses from Acufocus. Dr. Riha is a consultant to Acufocus. No other author has a financial or proprietary interest in any material or method mentioned.

Visual and optical performances of multifocal intraocular lenses with three different near additions: 6-month follow-up

Purpose :

To compare the visual and optical outcomes of four multifocal intraocular lenses (IOLs) with three different near additions of +3.00 diopters (D), +3.75 D and +4.00 D.

Methods :

In this prospective study, 133 eyes of 88 patients were implanted with one of the following IOLs: AcrySof^® ReSTOR^® SN6AD1 (+3.00 D) for Group A, Acriva^UD Reviol BB MF 613 or BB MFM 611 (+3.75 D) for Group B, and AcrySof^® ReSTOR^® SN6AD3 (+4.00 D) for Group C. The visual acuity, refraction, intraocular pressure, tomography and corneal endothelial cell density (ECD) were compared between the three groups preoperatively and at 6 month postoperatively. Defocus curve, contrast sensitivity and higher order aberrations (HOAs) at 6 month postoperative visit were measured and compared.

Results :

There were no statistically significant differences in distance visual acuity, refraction, intraocular pressure or ECD among the three groups after 6 months (P > 0.05). The photopic contrast sensitivity in Group C was statistically better than in Group A (P < 0.05). The scotopic ocular aberration in Group B was statistically greater compared to that in Group A (P < 0.05). The highest near-visual peaks were -0.06 logMAR at a -2.50 D (40 cm) in Group A, -0.07 logMAR at -3.00D (33 cm) in Group B, and -0.06 logMAR at -3.50 D (29 cm) in Group C. Statistically significant differences in near and intermediate visual acuities were observed among the three groups at -2.00 D (50 cm), -2.50 D (40 cm), -3.50 D (29 cm) and -4.00 D (25 cm) (P < 0.01).

Conclusion :

AcrySof^® ReSTOR^® SN6AD1 IOLs (+3.00 D) and SN6AD3 (+4.00 D) IOLs provided the best intermediate and near vision, respectively. Both intermediate and near vision were comparatively better in the eyes with Acriva^UD Reviol BB MFM 611 IOLs or BB MF 613 IOLs (+3.75 D).

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.

Ultra-wide-field retinal images in an eye with a small-aperture corneal inlay

We evaluated the ultra-wide-field retinal images for a 53-year-old man who developed peripheral retinal tears in an eye implanted with a Kamra corneal inlay after laser in situ keratomileusis. The peripheral fundus was photographed using the ultra-wide-field Optos imaging system. The images had a dark ring in the center of the retinal images that moved with eye movement. Photographs of the peripheral retinal tears were taken by directing the eye laterally to move the dark ring away from the retinal tears. The retinal tears were photocoagulated while viewing the retina through a wide-angle contact lens and with the eye directed laterally. We recommend using a wide-angle viewing lens to examine and treat an eye implanted with a corneal inlay.

FINANCIAL DISCLOSURE

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

Retrospective evaluation of the influence of pupil size on visual acuity after KAMRA inlay implantation

PURPOSE

To investigate the influence of pupil size on visual acuity after KAMRA inlay (AcuFocus, Inc., Irvine, CA) implantation.

METHODS

Five hundred eighty-four presbyopic eyes of 584 patients who underwent LASIK were evaluated. Uncorrected near visual acuity (UNVA), uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and corrected near visual acuity (CNVA) were measured. Two groups were classified: small pupil (pupil diameter < 6 mm) and large pupil (pupil diameter ≥ 6 mm) for both mesopic (pupil diameter < 4 mm) and photopic (pupil diameter ≥ 4 mm) pupil size parameters. The follow-up period was 6 months.

RESULTS

There were no significant differences in UNVA (P = .98) and CNVA (P = .16) between the mesopic pupil size groups; however, there were significant differences in UDVA (P = .023) and CDVA (P = .039). There was a weak correlation between pupil size and UDVA of the large mesopic pupil size group (rs = 0.129, P = .04). There were no significant differences in UNVA (P = .78), CNVA (P = .92), UDVA (P = .19), and CDVA (P = .60) for the photopic pupil size groups.

CONCLUSIONS

Pupil size does not have an influence on the resultant visual acuity after KAMRA inlay implantation. No correlation was found between preoperative and postoperative pupil size and visual acuity for the mesopic pupil groups.

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.

Evaluating the short-term results of KAMRA inlay implantation using real-time optical coherence tomography-guided femtosecond laser technology

PURPOSE

To evaluate the outcomes from using real-time optical coherence tomography (OCT)-guided femtosecond laser technology for pocket creation for KAMRA inlay (Acufocus, Inc., Irvine, CA) implantation surgery.

METHODS

One hundred fifty-one eyes underwent KAMRA inlay implantation using the real-time OCT-guided femtosecond laser for pocket creation. All patients had a history of prior LASIK. Uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, corrected near visual acuity, and manifest refraction spherical equivalent were evaluated preoperatively and postoperatively. The follow-up period was 3 months.

RESULTS

Mean manifest refraction spherical equivalent, uncorrected distance visual acuity, and uncorrected near visual acuity changed from -0.18 ± 0.33 to -0.95 ± 0.64, 20/16 to 20/20, and J8 to J2, respectively. Corrected distance visual acuity and corrected near visual acuity remained stable before and after KAMRA inlay implantation, 20/12 and J1, respectively.

CONCLUSIONS

Using real-time OCT-guided femtosecond laser technology increases the safety and accuracy of corneal KAMRA inlay implantation surgery with a history of prior LASIK with excellent visual and refractive outcomes.

Outcomes of small aperture corneal inlay implantation in patients with pseudophakia

PURPOSE

To evaluate the improvement in near visual acuity after KAMRA corneal inlay (AcuFocus, Inc., Irvine, CA) implantation in patients with pseudophakia.

METHODS

A retrospective study analysis of patients with pseudophakia undergoing monocular corneal inlay implantation in the non-dominant eye was performed. The inlay was implanted monocularly in the non-dominant eye of patients. Manifest refractive spherical equivalent, uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, and corrected near visual acuity were evaluated. The follow-up period was 3 months.

RESULTS

Thirteen eyes from 13 patients were evaluated. Four patients underwent LASIK for improved distance acuity at the time of inlay implantation. Mean uncorrected near visual acuity improved five lines (from J10 to J4) postoperatively. Mean uncorrected distance visual acuity, corrected distance visual acuity, and corrected near visual acuity remained stable and were 20/20, 20/16, and J1, respectively, before and after KAMRA implantation. Three eyes lost two lines and 1 eye lost one line of uncorrected distance visual acuity. Two eyes lost two lines and 1 eye lost 1 line of corrected distance visual acuity. Mean manifest refractive spherical equivalent changed before and after KAMRA implantation from -0.01 ± 1.07 diopters (D) (range: 2.25 to -1.88 D) to -1.12 ± 0.87 D (range: 0.25 to -2.75 D), respectively.

CONCLUSIONS

Implantation of a small aperture corneal inlay improved uncorrected near visual acuity while maintaining uncorrected and corrected distance visual acuity in monofocal patients with pseudophakia.