Small-Aperture Intracorneal Inlay: 3-Year Results
Journal of Cataract and Refractive Surgery
Good results have been achieved with the small-aperture corneal inlay in presbyopic adults, but sample sizes and follow-up time have been limited. Vukich et al. reported 36-month findings of the prospective U.S. investigational device exemption (IDE) clinical trial. The data confirmed the safety and effectiveness of the inlay procedure.
The trial involved 507 patients (45-60 years of age) with emmetropic presbyopia. In all patients, distance visual acuity (VA) had been corrected to 20/20 in both eyes. The Kamra small-aperture inlay (AcuFocus) was placed in the nondominant eye, which had uncorrected near visual acuity (UNVA) of 20/40 to 20/100 and cycloplegic refractive spherical equivalent of +0.50 D to –0.75 D, with ≤0.75 D of refractive cylinder, and required near correction of +1.00 D to +2.50 D (reading addition). Other criteria for recipient eyes were minimum central corneal thickness ≥500 μm, corneal power ≥41.00 D, all meridians ≤47.00 D, and endothelial cell count >2,000/mm2.
Thirty-six months after implantation, eyes in the effectiveness cohort (n = 417) exhibited 3.5 D of defocus range above 20/40. Monocular UNVA was 20/40 or better in 363 patients (87.1%), and binocular UNVA was 20/40 or better in 391 patients (93.8%). Patients who received the inlay via a femtosecond laser pocket procedure with a spot/line setting of 6 μm × 6 μm or tighter had the most improvement in near vision: 131 (90.3%) and 137 (94.5%) of these 145 patients had 20/40 or better monocular and binocular UNVA, respectively. Uncorrected distance VA of 20/25 or better was maintained in nearly all of these eyes.
Following the surgery, less than 1.5% of eyes lost 2 or more lines of corrected distance VA for 3 months or longer. Forty-four inlays (8.7%) were removed during the 3-year period, and 6 were repositioned. Deeper placement correlated with lower removal rates. Less than 1% of patients reported severe glare or halos. Overall, corneal health was maintained through 36 months postoperatively.
The original article can be found here.