EyeWorld India September 2019 Issue

EWAP SEPTEMBER 2019 53 REFRACTIVE (logMAR 0.1), uncorrected intermediate visual acuity was 20/24 (logMAR 0.1), and near visual acuity was J3 for two patients and J8 and J10 for the other two. The KAMRA was implanted in eyes with prior Crystalens IOL implants Õ`iÀ > `ii« >i>À y>«° /i mean corneal thickness was xxÓ ù «ÀÀ Ì >i>À y>« creation. The mean corneal y>« ÌViÃÃ VÀi>Ìi` Ü>Ã Óän ù° ƂÌ Ìi £Þi>À vÜÕ«] > patients noted improvement of uncorrected intermediate and near vision, with minimal impact on distance acuity (Tables 1 and 2). There was a modest reduction in monocular but not binocular contrast sensitivity. Results were stable at 4 years of follow-up, and there were no photic complaints. In addition to their use in patients with monofocal IOLs, Dr. Fox and colleagues present two cases where KAMRA was used in patients with bilateral multifocal IOLs Ü ÜiÀi `ÃÃ>ÌÃwi` ÜÌÌiÀ near vision or complained of photic phenomenon. Generally, the approach to such patients is to methodically correct any residual refractive error, assess the lens capsule and treat even small amounts of PCO, aggressively treat dry eye, evaluate the macula for conditions that can Ài`ÕVi VÌÀ>ÃÌ] >` w>Þ allow adequate time for neuroadaptation. In Cases 2 and 3, Dr. Fox and colleagues took another approach. The residual refractive error was left uncorrected in the dominant eye and a KAMRA inlay was implanted in the nondominant eye, in one case associated with simultaneous PRK with a –0.75 D target and in the other leaving the eye with –0.62 D spherical equivalent. Optically, this combination of a A B C D UCDVA 20/20 (0) 20/40 (0.3) 20/20 (0) 20/20 (0) UCIVA 20/16 (–0.1) 20/20 (0) 20/16 (–0.1) 20/20 (0) UCNVA J2 (0.10) J1+ (–0.10) J1+ (–0.10) J1+ (–0.10) BCDVA 20/20 (0) 20/20 (0) 20/20 (0) 20/20 (0) BCIVA 20/16 (–0.10) 20/20 (0) 20/25 (0.1) 20/20 (0) DVNVA J2 (0.1) J3 (0.18) J3 (0.18) J1+ (0.18) BCNVA J1+ (–0.1) J1+ (–0.10) J1+ (–0.10) J1+ (–0.10) Table 1. 1-year postoperative visual acuity (Snellen/logMAR). A B C D Sphere 0 –1.00 –1.00 0 Cylinder 0 –0.75 –0.25 –0.50 Sph. Equiv. 0 –1.375 –1.125 –0.25 Adds 1.00 1.00 1.00 0 Table 2. 1-year postoperative manifest refraction (D). C orneal inlay with small aperture (1.6 mm, by KAMRA) was designed to increase depth of focus and improve the near visual acuity. Its design has undergone several changes to «ÀÛi Ìi «ÞÃ}V ÕÌÀÌ> yÜ >` > ÕLiÀ v ÃÌÕ`iÃ >Ûi ÃÜ ÌÃ Ã>viÌÞ >` ivwV>VÞ >vÌiÀ ÌÃ Ƃ >««ÀÛ> Óä£x° 9iÌ there are several factors we need to consider before implanting the pinhole inlay. Firstly, depending on the optic design (e.g., spherical aberration, SA) of the IOLs, the refractive power in the central diameter of less than 2 mm, i.e. smaller than the standard measurement range of 3 mm, can be higher or lower than the standard refractive power. IOLs with positive SA will show somewhat lower power in the central smaller optical zone to a certain degree (0.2–0.3 D). Secondly, despite the reversible nature of the procedure without having to remove any tissue, several issues have been raised in recent years such as development of interface haze. Although these complications could be treated fully in most cases, some Ài«ÀÌÃ ÃÜi` «iÀÃÃÌiÌ>âi À wLÀÃÃ Ìi ÌiÀv>Vi `iÃ«Ìi iÝ«>Ì>Ì >` >Ìy>>ÌÀÞ ÌÀi>ÌiÌ° Amigo et al. recently observed late-onset (6 to 19 months) refractive shifts, with hyperopic shift in four cases and a myopic shift in one case. A total of four cases resulted in inlay explantation, and while two cases showed complete regression, the other two cases still showed haze at 23 and 32 months after explantation, respectively. 1 Norman et al. also reported a case with visual reduction after 6 years of uneventful postoperative period. Decreased visual acuity >` wLÀÃÃ ÜiÀi Ìi` >Ì n ÌÃ >vÌiÀ iÝ«>Ì>Ì] ÜV`` Ì respond to steroid treatment. 2 ƂÌÕ}À>Ài] Ìi >vÀiiÌi` wLÀÃÃ V«V>ÌÃ >Þ be correlated to the unclear immunologic response to the foreign material and design of the inlay itself. Changes in vision or refraction in any direction (better or worse near vision/hyperopic or myopic shifts compared to early stable postoperative period) should be evaluated carefully to rule out any pathologic changes in the cornea. Finally, careful consideration of indication, regular monitoring and early explantation may be crucial to avoid any complications. References 1. Amigó A, et al. Late-onset refractive shift after small-aperture corneal inlay implantation. J Cataract Refract Surg . 2018 May;44(5):658–664. Ó° ,Ì ] iÌ >° *iÀÃÃÌiÌ VÀi> wLÀÃÃ >vÌiÀ iÝ«>Ì>Ì v > Ã> aperture corneal inlay. J Cataract Refract Surg . 2019 Mar;45(3):367–371. 'FKVQTUo PQVG &T %JQK FGENCTGF PQ TGNGXCPV ƂPCPEKCN KPVGTGUVU Chul Young Choi, MD Professor, Sungkyunkwan University, Kangbuk Samsung Medical Center, Seoul, South Korea cychoi501@skku.edu ASIA-PACIFIC PERSPECTIVES continued on page 58