KAMRA Corneal Inlay Research Articles

KAMRA presbyopic inlay refractive outcomes: a Canadian perspective

ObjectifProcéder à une analyse rétrospective des résultats visuels suivant l'insertion de l'implant (ou inlay) cornéen KAMRA® (AcuFocus Inc., Irvine, Californie) dans une cohorte de patients et présenter les données quant à la réussite de l'intervention, aux complications, à la satisfaction des patients et aux résultats réfractifs. NatureÉtude rétrospective réalisée au TLC Laser Centre, à Toronto. MéthodesAu total, 5 chirurgiens de l’établissement ont procédé à l'insertion de 35 implants KAMRA® chez 35 patients entre octobre 2012 et juin 2014. Certains patients ont fait l'objet de la simple insertion de l'implant KAMRA®, tandis que d'autres ont fait l'objet à la fois d'une correction de la vision au laser et de l'insertion de l'implant KAMRA® le même jour ou lors de 2 interventions distinctes. Une petite cohorte de patients avait déjà fait l'objet d'une correction de la vision au laser sans lien avec l'implant cornéen. Le suivi moyen était de 299 jours. RésultatsOn a noté, après l'insertion de l'implant KAMRA®, une amélioration significative de l'acuité visuelle non corrigée de près (p = 0,00009), de l'acuité visuelle non corrigée à distance intermédiaire (p = 0,00006) et de l'acuité visuelle non corrigée de loin (p = 0,02). Or, le taux d'insatisfaction des patients se chiffrait à 43 %. La principale raison de cette insatisfaction tenait à la nécessité de porter des lunettes de lecture (23 %), suivie des dysphotopsies (11 %). Le taux d'explantation s’élevait à 11,42 %, tandis que 28,5 % des patients ont dû subir une retouche après l'insertion de l'implant. ConclusionsL'implant (ou inlay) cornéen KAMRA® procure des améliorations significatives de l'acuité visuelle non corrigée de près, de l'acuité visuelle non corrigée à distance intermédiaire et de l'acuité visuelle non corrigée de loin, qu'il ait été utilisé en association ou non avec une correction de la vision au laser. Il est essentiel de bien choisir les patients. Cette intervention ne doit pas servir à la prise en charge de la presbytie en première intention, compte tenu de la piètre satisfaction des patients, des enjeux de biocompatibilité et des taux d'explantation.

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

PurposeTo evaluate 10 years of KAMRA corneal inlay explantation and associated visual outcomes.Patients and MethodsSingle-site retrospective chart review of 22 cases of AcuFocus KAMRA Inlay (ACI7000PDT) explantation (range 1 week–1 year). Uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), and manifest refraction at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year post-explantation were reviewed.ResultsThe explantation rate was 8.2% across 10 years. All patients underwent KAMRA explantation due to dissatisfaction with their vision including blurry near vision, impaired night vision, decreased vision in dim lighting, streaks or halos, haze, and double vision. Mean UDVA pre-implant was −0.01±0.13 logMAR (logarithm of the minimal angle of resolution), 0.30±0.22 logMAR pre-explant, and 0.16±0.15 logMAR post-explant (n=20). Mean UNVA pre-implant was 0.37±0.09 logMAR, 0.38±0.13 logMAR pre-explant, and 0.42±0.21 logMAR post-explant (n=20). Mean CDVA pre-implant was −0.01±0.04 logMAR and 0.05±0.11 logMAR post-explant (n=17). Mean CDVA pre-explant was 0.04±0.07 logMAR and 0.04±0.11 logMAR post-explant (n=19). Significant differences were observed between pre-implant and post-explant UDVA (p=0.009), and between pre-explant and post-explant UDVA (p=0.02). All patients (100%) had 20/20 or better CDVA pre-implant but decreased to 73.7% post-explant. Sixty percent (12/20) of the patients lost UDVA Snellen acuity lines post-explant. MRSE was −0.31±0.29 D pre-implant and +0.26±0.77 D post-explant (p=0.007) with note of a hyperopic shift. The hyperopic shift in 31.6% (6/19) of patients did not resolve after explantation. Post-explant residual corneal haze occurred in 72.7% (16/22) of patients.ConclusionAlthough the KAMRA corneal inlay is a removable device, patients may experience residual corneal haze, hyperopic shift, and deficits in UDVA after explantation compared to pre-implantation UDVA.

Review of 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.

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.

Adaptation to Brightness Perception in Patients Implanted With a Small Aperture

PurposeSmall apertures are successfully used to extend depth of focus in presbyopic patients implemented either as corneal inlays or intraocular lenses. The use of small apertures reduces retinal illuminance. In this study, we quantify the relative perceived brightness in the 2 eyes of patients implanted monocularly with a small-aperture inlay.DesignProspective case series.MethodsWe used a binocular adaptive optics vision simulator to determine the relative perceived brightness. Four patients implanted monocularly with the KAMRA corneal inlay (1.6 mm) and a group of control subjects participated in the study. The projected pupil on the eye implanted with the inlay alternated in diameter between 0 and 2.5 mm (effective 1.6 mm) to eliminate potential for light to project around the periphery of the inlay while the corresponding fellow eye projected pupil alternated between 0 and 3.0 mm or 0 and 4.0 mm at a frequency of 1 Hz. Alternation on both eyes was synchronized so that only 1 eye at a time had a nonblocked pupil. At equal transmittance, a flickering was perceived. Patients' task consisted of modifying the transmittance of the pupil corresponding to the fellow eye until the perceived flickering, owing to the different perceived brightness, was minimized. This equalizing transmittance (ET) value indicates the relative perceived brightness.ResultsIn the KAMRA's patients, ET was found to be greater than expected considering the difference in pupil sizes and the Stiles-Crawford effect, showing an enhanced a greater brightness perception in the eye with the small aperture in comparison with the fellow eye. Compared with the control subjects, this difference was on average bigger by a factor of ×1.42.ConclusionsPatients implanted with the small-aperture corneal inlay exhibited an enhanced brightness perception with the eye implanted, in comparison with their untreated fellow eye. The amount of this increase is much larger than what could be expected owing to the Stiles-Crawford effect and was probably attributable to a neural adaptation process. This phenomenon could explain a reported equalization of brightness between eyes in patients with unilateral inlays and implies that the expected reduction of brightness may have a less significant impact on these patients, as expected.

Cataract Surgery in Patients with a Previous History of KAMRA Inlay Implantation: A Case Series

IntroductionThe visual outcome of cataract surgery in patients with a previous history of KAMRA inlay implantation is an emerging issue for which limited research exists. The purpose of this study is to describe postoperative visual outcomes in this patient population.MethodsThis is a case series with retrospective chart review. Seven patients underwent cataract surgery following KAMRA corneal inlay implantation. Visual acuity was assessed before and after cataract surgery. Keratometry was measured before and after KAMRA inlay implantation, and optical biometry was performed prior to cataract surgery.ResultsPostoperatively, uncorrected distance visual acuity (UDVA) was 20/20 in five (71%) patients and 20/40 or better in seven (100%) patients, corrected distance visual acuity (CDVA) was 20/20 or better in six (86%) patients and 20/25 in seven (100%) patients, and uncorrected near visual acuity (UNVA) was J1 in four (57%) patients, J2 or better in six (86%) patients, and J3 or better in seven (100%) patients. There was no significant change in keratometry after KAMRA inlay implantation. Biometry calculations accurately predicted intraocular lens (IOL) power after cataract surgery. Surgeons did not report a significant change in the surgical technique of cataract surgery.ConclusionPatients who undergo cataract surgery with a previous history of KAMRA inlay implantation have good visual outcomes. Furthermore, intraocular lens (IOL) calculations accurately predict power, and there appears to be no significant change in surgical technique.

Effects of femtosecond and excimer lasers on implanted KAMRA corneal inlay in animal models

To evaluate the effect of femtosecond laser and excimer laser on an intracorneal inlay (KAMRA®) implanted in animal models. Femtosecond laser was used to create corneal intrastromal pockets at 250μm depth in five porcine eyes. Four intact KAMRA inlays, examined by slit-lamp biomicroscopy and light microscopy, were implanted in the pocket of four eyes. A standard LASIK flap was created above each implanted inlay in the four eyes using a femtosecond laser with flap thicknesses of 150μm, 130μm, 110μm and 90μm. In the fifth porcine eye, a LASIK flap was created using femtosecond laser at 110μm depth, and a fifth inlay was then implanted in the 250μm pocket. Excimer laser ablation was performed under the flap targeting a -3.00 refraction. The inlay was then explanted, examined and reimplanted in the same pocket followed by a second similar excimer laser ablation. Significant burn, shrinkage and distortion of microholes were noted in all the first four inlays following the femtosecond laser flap creation at all the various flap thicknesses. The damage was noted to be more prominent as the distance between the flap and inlay decreased. No apparent effect was noted on the fifth inlay following repeated excimer laser ablations. Unlike excimer laser, femtosecond laser appears to be hazardous and damaging to the intracorneal KAMRA inlay when applied above it.

KAMRA corneal inlay for the correction of presbyopia

This is a case report of two patients who underwent presbyopia correction with KAMRA corneal inlay (KAMRA; AcuFocus, Irvine, CA) combined with LASIK surgery. The surgical technique is thoroughly explained, as well as the advantages and disadvantages of the procedure. In both patients, near uncorrected visual acuity significantly improved and distance uncorrected visual acuity remained unchanged. There were no changes in the corneal topography after the corneal inlay implantation.

Stereoacuity after small aperture corneal inlay implantation.

PurposeThe aim of this study was to compare stereoacuity before and after KAMRA corneal inlay implantation for the correction of presbyopia.Patients and methodsThis is a prospective study of 60 patients who underwent KAMRA inlay implantation. Patients were examined before and 6 months after surgery for stereoacuity, uncorrected distance visual acuity (UDVA), and uncorrected near visual acuity (UNVA).ResultsThe mean stereoacuity before surgery was 29.5±28.1 arcsec (range: 20–200) and at 6 months was 29.8±26.4 arcsec (range: 20–200). The decline in stereoacuity was not statistically significant. At 6 months follow-up, UDVA was 20/25 or better in all 60 patients and UNVA was J2 (20/25) or better in 51 (85%) patients.ConclusionThere is no significant change in stereoacuity following KAMRA inlay implantation. The KAMRA inlay is a good treatment option for improving near vision in presbyopic patients while preserving stereoacuity and distance vision.

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

ObjectiveThe 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 designThis study followed a retrospective chart analysis.SettingThis study was performed at Hoopes Vision in Draper, UT, USA.Subjects and methodsFifty-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.ResultsAt 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.ConclusionFor 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.

Effect of the Femtosecond Laser on an Intracorneal Inlay for Surgical Compensation of Presbyopia during Cataract Surgery: Scanning Electron Microscope Imaging

ABSTRACTPurpose: To investigate the effect of the femtosecond laser-assisted cataract surgery (FLACS) on porcine eyes implanted with a Kamra corneal inlay and to describe how the inlay may change the effect of the femtosecond laser on the lens.Methods: FLACS was performed on six porcine eyes and a Kamra corneal inlay had been implanted, exploring the lens under the surgical microscope. Another Kamra corneal inlay was attached to the upper part of the transparent hemisphere used for calibration of the femtosecond laser. Capsulorhexis, arcuate incisions, and phacofragmentation were carried out. The Kamra corneal inlay was compared with a nontreated one using a scanning electron microscope (SEM), and the hemisphere was analyzed with a surgical microscope.Results: Capsulorhexis and phacofragmentation were completed in all the porcine eyes, although accuracy to determine the exact effect on the lens was not possible to achieve. The effect of the femtosecond laser on the PMMA hemisphere through the Kamra corneal inlay showed the capsulorhexis was placed outside the outer margin of the inlay and a sharply sculpted fragmentation pattern with a three-dimensional (donut-shaped) annulus untreated beneath it. SEM images of the nontreated and the treated inlays were comparable. No ultrastructural changes were found in the treated Kamra corneal inlay.Conclusions: FLACS can be performed with a Kamra corneal inlay for surgical compensation of presbyopia without the risk of damaging the inlay. The Kamra corneal inlay acts as a screen that avoids the laser to reach the areas beneath its shadow, but not the exposed areas of the lens.

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.

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

To evaluate the quality of the image of a grating target placed in a model eye and viewed through a small-aperture corneal inlay. Kyorin Eye Center, Tokyo, Japan. Experimental study. 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. 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. 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. No author has a financial or proprietary interest in any material or method mentioned.

Outcomes of small aperture corneal inlay implantation in patients with pseudophakia.

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

Retinal images viewed through a small aperture corneal inlay

Presbyopia is a visual disability of the ageing eye caused by a loss of accommodation of the crystalline lens (Charman 2008). To treat presbyopia, the Kamra corneal inlay (AcuFocus, Inc., Irvine, CA, USA) was designed with a small aperture, which increases the depth of focus (Yılmaz et al. 2011; Tomita et al. 2012). The inlay is 5 μm thick and incorporates carbon nanoparticles to create a 3.8-mm-diameter opaque sheet with a clear central aperture of 1.6 mm with zero refractive power (Yilmaz et al. 2008). The inlay was reported not to affect the ophthalmoscopic view of the central and peripheral fundus, and high-quality central and peripheral fundus photographs and optical coherence tomographic (OCT) images could be obtained in eyes implanted with the inlay (Casas-Llera et al. 2011). However, it has not been determined how the inlay affects the retinal images when patients require vitreoretinal surgeries in eyes with dark-coloured rings in the centre of the cornea. A 48-year-old woman visited Minatomirai Eye Clinic for symptomatic floaters in the left eye implanted with a Kamra cornea inlay. Routine retinal examination was performed, including a detailed retinal examination with a slit-lamp microscope and a Goldmann three-mirror contact lens (OG3MFA; Ocular Instruments, Washington, DC, USA) after the pupil was dilated by a topical mydriatic drug. Fundus photographs were taken with a retinal camera (Mark2 NW7SF; Topcon Corp, Tokyo, Japan) with a 50-degree angle and fundus images through a three-mirror contact lens with a slit-lamp microscope connected to a video camera mounted on a slit-lamp microscope. The uncorrected decimal distant vision in the left eye of the patient implanted with the inlay was 1.2, and the uncorrected near vision was 0.8. The funduscopic images through the indirect ophthalmoscope and fundus photographed through the inlay were clear (Fig. 1). However, with a slit-lamp microscope, a blurred dark ring was observed through the centre lens of the Goldmann three-mirror contact lens. When the focus was moved to the cornea, the dark ring became sharper and was noticed to originate from the inlay. In the fundus image through the Goldmann three-mirror contact lens, another dark shadow projected on the retina was observed aside of the dark ring, which moved according to the direction of the slit-light beam by shifting a slit-lamp lever and was considered to be a shadow of the inlay. The central lens of the Goldmann three-mirror lens has a flat front surface, and it had the same optical structure as the flat contact lens used for vitrectomy but without endoillumination. The light passes through all parts of the optics of the crystalline lens or the intraocular lens (IOL) within the diameter of the pupil with the flat or prism contact lens system during vitreous surgery or a three-mirror contact lens. This is the reason why a defocused dark ring was observed in the visual field with a three-mirror contact lens. Yılmaz et al. (2011) described two cases that underwent phacoemulsification with IOL implantation with no intraoperative complications 3 and 4 years after the inlay implantation. When vitreous surgery was performed with a flat contact lens and the focus was on the retina, the dark ring was more defocused resulting in a decrease in contrast of the retinal images. To avoid blocking the view of the retina, the eye must be rotated during vitreous surgery. Otherwise, the corneal inlay can be removed before the vitreoretinal surgery. Using a wide-angle viewing system which has a similar optical system as the indirect ophthalmoscope and fundus camera, may be recommended to increase the quality of view.

Corneal inlay implantation in a young pseudophakic patient

We describe the surgical correction of a 32-year-old pseudophakic patient with the Kamra corneal inlay. To our knowledge, this is the youngest patient to have such a procedure. Neither author has a financial or proprietary interest in any material or method mentioned.

Vignetting and Field of View with the KAMRA Corneal Inlay

Purpose. To evaluate the effect of the KAMRA corneal inlay on the retinal image brightness in the peripheral visual field. Methods. A KAMRA inlay was “implanted” into a theoretical eye model in a corneal depth of 200 microns. Corneal radius was varied to a steep, normal, and flat (7.37, 7.77, and 8.17 mm) version keeping the proportion of anterior to posterior radius constant. Pupil size was varied from 2.0 to 5.0 mm. Image brightness was determined for field angles from −70° to 70° with and without KAMRA and proportion of light attenuation was recorded. Results. In our parameter space, the attenuation in brightness ranges in between 0 and 60%. The attenuation in brightness is not affected by corneal shape. For large field angles where the incident ray bundle is passing through the peripheral cornea, brightness is not affected. For combinations of small pupil sizes (2.0 and 2.5 mm) and field angles of 20–40°, up to 60% of light may be blocked with the KAMRA. Conclusion. For combinations of pupil sizes and field angles, the attenuation of image brightness reaches levels up to 60%. Our theoretical findings have to be clinically validated with detailed investigation of this vignetting effect.

Femtosecond laser–assisted small-aperture corneal inlay implantation for corneal compensation of presbyopia: Two-year follow-up

To report the 2-year postoperative safety and efficacy outcomes after monocular Kamra corneal inlay (ACI7000PDT) implantation in femtosecond laser-created corneal pockets of emmetropic presbyopic patients to improve near and intermediate vision. University Eye Clinic, Paracelsus Medical University, Salzburg, Austria. Prospective interventional case series. Patients had corneal inlay implantation in the nondominant eye. Emmetropic presbyopic patients between 45 and 60 years old with an uncorrected distance visual acuity (UDVA) of 20/20 or better in both eyes and without additional ocular pathology were eligible. Contrast sensitivity, visual field examinations, endothelial cell count (ECC), and central corneal thickness (CCT) measurements were assessed preoperatively and 12 and 24 months postoperatively. The UDVA, uncorrected intermediate visual acuity (UIVA), and near visual acuity (UNVA) were assessed preoperatively and 1 day, 1 week, and 1, 3, 6, 9, 12, 18, and 24 months postoperatively. The minimum postoperative follow-up was 24 months. After 24 months, the mean binocular UNVA improved from 20/50 to 20/25; 20 patients (83%) had a UNVA of 20/25 or better. The mean binocular UIVA was 20/20. The mean UDVA was 20/20 in the surgical eye and 20/16 binocularly after 24 months. Contrast sensitivity under photopic and mesopic conditions remained in the range of the normal population. No patient had detectable central visual field defect. No inlay was explanted. No inflammatory reactions were observed. The ECC and CCT remained stable. The corneal inlay implanted in femtosecond laser-created pockets was effective and safe for the corneal compensation of presbyopia in emmetropic patients after 24 months. Acufocus Inc., Irvine, California, USA, financially supports the Research Foundation for Promoting Ophthalmology, Salzburg, Austria, as the clinical research center of the University Eye Clinic (Paracelsus Medical University). Dr. Grabner received travel expenses from Acufocus, Inc. Dr. Riha currently also works as a clinical application specialist for Acufocus, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Reading performance and patient satisfaction after corneal inlay implantation for presbyopia correction: Two-year follow-up

To evaluate change in reading performance parameters after monocular Kamra corneal inlay implantation for the surgical correction of presbyopia. University surgical outpatient center. Prospective interventional case series. A corneal inlay was implanted in the nondominant eye. Naturally emmetropic and presbyopic patients between 45 years and 60 years old with an uncorrected distance visual acuity of at least 20/20 in both eyes without additional ocular pathology were eligible for inclusion. Bilateral uncorrected reading acuity, reading distance, mean and maximum reading speed, and the smallest log-scaled print size (lower case letter of a Radner reading chart) were evaluated using the Salzburg Reading Desk. The minimum postoperative follow-up was 24 months. Twenty-four patients were enrolled. The mean reading distance was 46.7 cm ± 6.3 (SD) preoperatively and 39.5 ± 6.4 cm 24 months postoperatively (P<.001). The mean reading acuity at best distance improved (0.33 ± 0.13 logRAD versus 0.23 ± 0.11 logRAD) (P=.004). The mean reading speed increased from 141 ± 20 words per minute (wpm) to 146 ± 20 wpm, respectively (P=.261), and the mean maximum reading speed from 171 ± 28 wpm to 180 ± 22 wpm, respectively (P=.110). The smallest print size improved from 1.50 ± 0.42 mm to 1.01 ± 0.22 mm, respectively (P<.001). Improving the depth of focus by monocular implantation of a small-aperture optic caused statistically significant changes in all tested reading performance parameters except reading speed metrics in emmetropic presbyopic patients.

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

To evaluate the safety and efficacy of simultaneous Kamra corneal inlay implantation and laser in situ keratomileusis (LASIK) for the treatment of presbyopia in emmetropic, hyperopic, or myopic patients. Private center, Tokyo, Japan. Cohort study. Patients had bilateral LASIK with simultaneous implantation of a corneal inlay in the nondominant eye to treat presbyopia and ametropia between September 2009 and April 2010. The efficacy and safety were determined by the spherical equivalent (SE) in the eye with the inlay. The study enrolled 360 eyes of 180 patients with a mean age of 52.4 years ± 5.1 (SD) (range 41 to 65 years). Sixty-four patients were available for the 6-month postoperative examination. The mean logMAR uncorrected near visual acuity in the eye with the inlay improved 7 lines in hyperopic eyes, 6 lines in emmetropic eyes, and 2 lines in myopic eyes. The mean logMAR uncorrected distance visual acuity improved by 3 lines, 1 line, and 10 lines, respectively. Simultaneous intracorneal inlay implantation and LASIK to treat presbyopia with emmetropia, hyperopia, or myopia was clinically safe and effective, yielding improvement in distance and near visual acuity. Patients were satisfied with decreased dependence on reading glasses regardless of the preoperative SE range. However, postoperative symptoms, such as dry eyes, halo, glare, or night-vision disturbances, occurred occasionally. Dr. Waring has a financial interest in and is world surgical monitor for Acufocus. No other author has a financial or proprietary interest in any material or method mentioned.