Small-aperture Corneal Inlay Implantation Research Articles

Five-Year Results of Combined Small-Aperture Corneal Inlay Implantation and LASIK for the Treatment of Hyperopic Presbyopic Eyes.

To evaluate the efficacy of simultaneous laser in situ keratomileusis (LASIK) and small-aperture corneal inlay (KAMRA; AcuFocus, Inc) implantation in hyperopic presbyopic eyes at 5 years postoperatively. This was a retrospective single-center study of patients with hyperopia and presbyopia who underwent simultaneous LASIK and corneal inlay implantation by two experienced refractive surgeons. These patients were regularly observed for 5 years and evaluated with serial corneal tomographies and refractive assessments for uncorrected near visual acuity (UNVA), uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), distance-corrected near visual acuity (DCNVA), and manifest refraction spherical equivalent (MRSE). Twenty-four eyes of 24 patients were included. Mean age was 53.63 ± 4.11 years (range: 47 to 63 years) and mean preoperative MRSE was +1.52 ± 0.64 diopters (D) (range: +0.50 to +3.00 D). UNVA was 0.04 ± 0.06 logMAR at 1 month and 0.02 ± 0.05 logMAR (J1+ equivalent) at 5 years postoperatively. In comparison, preoperative DCNVA was 0.44 ± 0.20 (J5/J6 equivalent) (P < .001). At 5 years postoperatively, UDVA was 0.16 ± 0.18 logMAR (20/30 Snellen equivalent), and 23 of 24 eyes (95.8%) had UNVA of J3 or better. Two eyes (8.3%) lost one line of CDVA. One corneal inlay needed readjustment but none were explanted. Eight eyes (25%) developed regression in UNVA with hyperopic shift, which responded to a 3- to 4-month course of topical steroids, with 3 eyes showing patchy haze on the undersurface of the corneal inlay. Simultaneous LASIK and KAMRA inlay implantation, evaluated for 5 years postoperatively, shows some efficacy and predictability in improving UDVA and UNVA in hyperopic presbyopic eyes. However, late-onset regression with hyperopic shift, possible loss of CDVA, and occasional haze remain challenges. [J Refract Surg. 2020;36(8):498-505.].

Long-term changes in keratometry and refraction after small aperture corneal inlay implantation.

PurposeTo assess longitudinal refractive, keratometric, and topographic changes following KAMRA small-aperture inlay implantation.Design and settingProspective study at a single site refractive surgery center.MethodsFifty patients underwent KAMRA small-aperture corneal inlay implantation for the correction of presbyopia. Uncorrected near visual acuity (UNVA), uncorrected distance visual acuity, manifest refractive spherical equivalent (MRSE), mean keratometry (Km), corneal topography, and surgically induced astigmatism vector analysis assessments were performed preoperatively and at 1, 3, 6, 12, 24, and 36 months postoperatively.ResultsThe study comprises 50 eyes. An average shift of 0.15±0.63 D (range −1.63 to 2.00 D) occurred between preoperative baseline and 36 months. At 36 months, 54% of patients had hyperopic MRSE and 40% had myopic MRSE compared with baseline. Km was significantly elevated at all postoperative measurements compared with baseline, with the largest Km measured at 12 months. Eighty-six percent of patients had UNVA of 20/32 or better and 88% uncorrected distance visual acuity of 20/25 or better at 36 months. Longitudinal corneal topography revealed a pattern of corneal steepening over the body of the inlay and flattening over the aperture, correlating with a hyperopic shift. There was no significant surgically induced astigmatism.ConclusionKAMRA inlay may cause an increase in Km compared with baseline. Corneal steepening may occur in a specific pattern with steepening over the inlay and flattening over the aperture. This topographic pattern causes a hyperopic shift, which may be relevant for subsequent procedures, such as cataract extraction.

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

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. 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. 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. 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.].

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

To evaluate long-term outcomes of small-aperture corneal inlay implantation for the surgical compensation of presbyopia. Paracelsus Medical University, Salzburg, Austria. Prospective interventional cohort study. 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. 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. Long-term results of monocular corneal inlay implantation indicate increased UNVA and UIVA and slightly compromised UDVA in emmetropic presbyopic eyes. 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.

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

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. Shinagawa LASIK Center, Tokyo, Japan. Retrospective comparative cohort study. 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. 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. 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. 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.

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.

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.