Rotational Stability of a New Hydrophobic Acrylic IOL With Modified C-loop Haptics

Abstract

PURPOSE: To assess rotational stability, axial stability, decentration, and tilt of the Rayner RAO800C single-piece hydrophobic acrylic intraocular lens (IOL) (Rayner Intraocular Lenses Ltd) from end of surgery to 4 to 7 months postoperatively. METHODS: Surgeries were performed at the Department of Ophthalmology at the Medical University of Vienna. A total of 130 eyes of 68 patients received an aspheric hydrophobic Rayner RAO0800C IOL. IOLs were randomly implanted to the 0 ± 10, 45 ± 10, 90 ± 10, or 135 ± 10 degree axis. Baseline measurement was performed with the patient still supine on the operating table. Axis alignment after 1 hour, 1 week, 1 month, and 4 months was evaluated by retroillumination pictures. Postoperative IOL decentration, tilt, and aqueous depth at 4 months were assessed using an anterior segment swept-source optical coherence tomography. RESULTS: Absolute median IOL rotation from end of surgery to 4 months was 2.4 degrees (range: 0.0 to 85.0 degrees). Median IOL rotation from end of surgery to 1 hour, 1 hour to 1 week, 1 week to 1 month, and 1 month to 4 months was 1.6 (range: 0.0 to 86.2), 1.1 (range: 0.0 to 28.8), 0.6 (range: 0.0 to 5.2), and 0.7 (range: 0.0 to 2.6) degrees. Respective proportions of IOLs rotating more than 5, 10, and 20 degrees from end of surgery to 4 months were 23.9%, 11.0%, and 6.4%. Horizontal and vertical decentration at 4 months was −0.09 ± 0.14 and 0.09 ± 0.14 mm, respectively. Horizontal and vertical tilt at 4 months was −4.78 ± 1.36 and −1.58 ± 1.10 degrees, respectively. A posterior axial shift of 0.052 ± 0.055 mm was observed from 1 week to 4 months. CONCLUSIONS: Although median IOL rotation appeared to be low, a significant proportion of IOLs rotated postoperatively. Decentration and tilt values were generally low. A minimal posterior optic shift was observed after 1 week. [ J Refract Surg . 2021;37(2):112–118.]

Rotational Stability of Intraocular Lenses: A Standardized Method for More Accurate Measurements in Future Studies

“…In these studies, the same method was applied but the ruler tool of the Photoshop software used to compare IOL axis orientation with critical landmarks. 3,6,7 In conclusion, our highly reproducible method is easy to perform in clinical studies to assess rotational stability of intraocular lenses. It's robustness against head tilt, cyclorotation, autorotation and initial placement error of IOLs makes it a potential gold standard for future IOL rotational stability studies.…”

“…In all eyes, a non-toric hydrophobic acrylic single piece IOL was implanted. 3 Patients provided written informed consent prior to the study. All study procedures adhered to the tenets of the Declaration of Helsinki.…”

“…These technique can also be manually performed with Photoshop using the so called "ruler tool" and measuring the axis between the two lines. 3,6,7 If the reference line and the IOL line are not intersecting, the reference line connecting the two critical landmarks must be duplicated and shifted until it crosses the IOL axis line.…”