JCRS Highlights from Professor Thomas Kohnen, European Editor, JCRS

Swept-source OCT improves formula accuracy Preoperative biometry measurements using swept-source optical coherence tomography (SS-OCT) can be used to improve the refractive outcomes of IOL power calculation, researchers report. Italian investigators took preoperative measurements using the OA-2000 (Tomey Inc.) in a consecutive series of 150 eyes undergoing cataract surgery with one IOL model (AcrySof SN60WF; Alcon Laboratories, Inc.). They then entered the measurements into several formulas including: Barrett Universal II, Emmetropia Verifying Optical (EVO), Haigis, Hoffer Q, Holladay 1, Holladay 2, Holladay 2 with axial length adjustment, Kane, Olsen, Panacea, SRK/T, T2, and VRF. The SS-OCT biometry enabled accurate IOL power calculation, improving refractive outcomes, because all formulas yielded a prediction error within 0.50D in at least 80% of eyes. The Barrett, EVO, Holladay 2 with axial length adjustment, Kane, RBF and T2 achieved the highest percentages (≥88%). G Savini, et al., “Comparison of formula accuracy for intraocular lens power calculation based on measurements by a swept-source optical coherence tomography optical biometer”, 46(1): 27-33. Cosmetic iris implants Cosmetic iris implants carry risks for several ocular complications and decreased mean visual acuity in otherwise healthy young people, a multi-centre study concludes. Although originally developed to manage congenital or traumatic iris defects, the implants are also used to change the colour of patient eyes. The aim of this retrospective series was to report complications in patients managed in France after cosmetic implantation. An analysis of questionnaires collected from throughout France showed that only a small minority of patients did not experience any complications, while 92% did have at least one complication. The most common problem was corneal decompensation, followed by glaucoma. Most, 81.5%, required explantation. H El Chehab et al. “Complications of cosmetic iris implants: French series of 87 eyes”, 46(1):34-39, January 2020. PCIOL for high myopia and presbyopia A new posterior chamber phakic IOL (IPCL, EyeOL UK) appears to offer the promise of the correction of both high myopia and presbyopia. In a prospective cohort study, patients with presbyopia and moderate-to-high myopia received the lens. Follow-up evaluation conducted up to two-year postoperatively showed high-quality uncorrected distance and near visual acuity after the presbyopic phakic lens implantation. The mean distance refraction improved significantly from -6.9 dioptres (D) preoperatively to -0.35D. Near vision also improved, with 15 of 17 eyes gaining uncorrected near visual acuity to J1 (Jaeger chart) at the two-year follow-up. The hydrophilic acrylic IOL has a refractive optic and diffractive trifocal pattern on its anterior optical surface to correct distance and near refractive errors. P Stodulka et al., “Posterior chamber phakic intraocular lens for the correction of presbyopia in highly myopic patients”, 46(1):40-44, January 2020.

Tags: cataract and refractive