EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/78721
January 2012 EyeWorld journal club Review of "Small-aperture corneal inlay for the correction of presbyopia: 3-year follow-up" by R. Grant Morshedi, M.D., Brice J. Williams, M.D., Lloyd B. Williams, M.D., and Mark D. Mifflin, M.D. Mark D. Mifflin, M.D., program director, University of Utah, Salt Lake City This month I asked the University of Utah residents to review this interesting study on 3-year results of refractive corneal inlays from the January issue of the Journal of Cataract and Refractive Surgery. —David F. Chang, M.D., chief medical editor D espite the introduction of various surgical modali- ties in cataract and refrac- tive surgery, the safe and effective correction of presbyopia remains an elusive goal. Current approaches include surgical reshaping of the cornea or replace- ment of the crystalline lens. Either modality may attempt to achieve good uncorrected distance and near acuity through "monovision" or "blended vision," or alternatively through induction of multifocality of each eye individually. Lens plat- forms offer the additional possibility of movement of optical elements or "pseudoaccommodation." In the January issue of JCRS, Seyeddain et al. present "Small-aper- ture corneal inlay for the correction of presbyopia: 3-year follow-up" as a longitudinal update on a cohort originally presented in 2010.1 This prospective, non-randomized, inter- ventional cohort study followed 32 naturally emmetropic presbyopic patients in whom the AcuFocus Corneal Inlay (Irvine, Calif.) was implanted in the non-dominant eye. The AcuFocus Corneal Inlay is a ring-shaped implant designed to in- crease the depth of field by reducing the size of the optical aperture (the "pinhole effect"), an approach not currently utilized by other presby- opia-correction techniques. This im- plant received the CE mark for use in the European Union in 2005 and is currently under investigation in U.S. FDA trials. In this article, the authors prospectively collected a compre- hensive set of pre- and post-op data points, including manifest and cy- cloplegic refraction, uncorrected near, intermediate, and distance visual acuities, corrected distance visual acuity, contrast sensitivity, visual fields, patient satisfaction via questionnaire, and performance of various diagnostic tools (fundus ophthalmoscopy, gonioscopy, OCT of the macula and retinal nerve fiber layer, and scanning laser polarimetry of the nerve fiber layer with the GDx VCC). Analysis indicated that there was a significant improvement in the mean uncorrected near visual acuity (UNVA) in the surgical eye from J7/J8 pre-op to J1 at 36 months. Similarly, the mean uncor- rected intermediate visual acuity (UIVA) in the surgical eye signifi- cantly improved from 20/40 pre-op to 20/25 at 1 month, remaining sta- ble throughout the follow-up period. The objective gains reported are sub- jectively validated by inclusion of data from a manufacturer-designed patient questionnaire, where pa- tients reported significantly better near and intermediate vision scores 36 months post-op, as well as signifi- cantly reduced spectacle dependency for near tasks at 36 months. The mean uncorrected distance visual acuity (UDVA) in the surgical eye significantly decreased from 20/16 pre-op to 20/20 at 1 month, where it remained throughout the follow-up. However, the post-op mean binocular UDVA (perhaps a better indication of patients' func- tional status) was unchanged from the pre-op level. The questionnaire data show no change in distance vi- sion while watching a movie but a worse score for distance vision while driving at night (the authors do not report whether this was statistically significant). The decrease in monoc- ular UDVA and night driving dis- tance vision in some patients can possibly be explained by a reduction in illumination due to the corneal inlay, which is suggested by the sig- nificant decrease in visual field in- dices (mean deviation and pattern standard deviation) during the fol- low-up period and the small loss of contrast sensitivity in the surgical eyes. The authors question the clini- cal significance of this finding even though seven patients reported moderate or severe symptoms while driving at night. Perhaps the most important outcome parameter reported is the questionnaire item that asked whether the patients would have the surgical treatment again. Of the pa- tients, 84.5% answered yes, 12.5% were undecided, and 3.0% (1 patient) an- swered no. No amount of objective data can supplant this important meas- ure of patient satis- faction. The only patient who an- swered no was one who had multiple subsequent proce- dures due to flap striae. In their previ- ous publication,1 the EW RESIDENTS 61 Figure 1 authors reported that this patient's reason was a "subjec- tively insufficient improvement in UNVA," despite being J1 at last fol- low-up. Another potentially impor- tant issue not addressed by the study is the patient satisfaction with the cosmetic result of the procedure. Figure 1, although a slit lamp microscopic photo, indicates that the corneal inlay is likely to be read- ily visible externally, which may be important to some patients if their motivations for spectacle independ- ence are cosmetic. The data indicate no serious safety issues, with a statistically sig- nificant but clinically insignificant loss of endothelial cell density, no patients who required explantation, no evidence of inflammatory reac- tions or deposits, and clinically in- significant epithelial iron deposits in continued on page 62 Small-aperture corneal inlay for the correction of presbyopia: 3-year follow-up Orang Seyeddain, M.D., Melchior Hohensinn, M.D., Wolfgang Riha, M.D., Gerhard Nix, M.D., Theresa Rückl, M.D., Günther Grabner, M.D., Alois K. Dexl, M.D., M.Sc. J Cataract Refract Surg (January) 2012; 38:35–45 Purpose: To report the 3-year post-op safety and efficacy outcomes of the AcuFocus corneal inlay Setting: University Eye Clinic, Paracelsus Medical University, Salzburg, Austria Design: Prospective, non-randomized, non-comparative cohort study Methods: The corneal inlay was implanted in the non-dominant eye of naturally emmetropic presbyopic patients. Refraction, uncorrected near (UNVA), intermediate (UIVA), and distance (UDVA) visual acuities; corrected distance visual acuity (CDVA); contrast sensitivity; visual fields; subjective patient satisfaction and symptoms; and operative and post-operative adverse events and complications were evaluated. Results: The study enrolled 32 patients. The mean UNVA improved from Jaeger (J) 6 pre- operatively to J1 at 3 years and the mean UIVA, from 20/40 to 20/25, respectively. At 3 years, 97% of eyes had a UNVA of J3 or better and 91% had a UIVA of 20/32 or better. The mean UDVA was 20/20, with all eyes achieving 20/32 or better. Nine eyes (28.3%) lost 1 line of CDVA, 1 eye (3.1%) lost more than 2 lines (3.8 lines), and 3 eyes (9.3%) gained 1 line. No inlay was explanted, and no inflammatory reactions were observed. At 3 years, 15.6% of patients reported severe night-vision problems and 6.3% (versus 87.5% pre- operatively) reported being dependent on reading glasses. Conclusions: These 3-year results support the safety and efficacy of the corneal inlay to correct presbyopia in naturally emmetropic presbyopic patients. However, despite a significant gain in UNVA and UIVA, 28.3% of patients lost 1 line of CDVA.