Taking Stock of Off-the-Shelf Toric IOLs

Study highlights possible benefits of off-the-shelf toric IOLs. Dermot McGrath reports. Using off-the-shelf toric IOL models does not appear to be inferior to using a fully tailored approach for patients with up to 5.0 D of preoperative astigmatism, a new study suggests. “The use of off-the-shelf toric lenses with additional opposite clear corneal incisions may improve visual acuity and allow patients to achieve spectacle independence for distance vision. Our preliminary data suggests that it may not be inferior to using fully tailored toric IOLs,” said Khayam Naderi MD. Explaining the rationale for the study, Dr Naderi said up to 20% of patients undergoing cataract surgery in the National Health Service in the United Kingdom have preoperative astigmatism of more than 1.5 D. “We know that there are several associated benefits to toric IOLs compared to monocular lenses, including greater rates of spectacle independence, better quality of life scores, and a reduced economic burden for patients. Nevertheless, toric IOLs are only available to a small proportion of NHS hospitals due to their increased associated costs and storage issues. By having a reduced in-house bank of toric lenses, we can potentially reduce these costs, allowing NHS patients routine access to them and their associated refractive benefits,” he said. Dr Naderi’s prospective single-masked randomised casecontrolled trial compared the visual performance and refractive outcomes of off-the-shelf toric lenses with a set cylindrical correction of 2.0 D or 4.0 D and additional clear corneal incisions as required for a fully tailored approach. The study included 66 patients with pre-existing regular corneal astigmatism of 1.50 D or more, 32 of whom were randomised to the fully tailored treatment group and 34 patients in the off-the-shelf toric IOL group. The visual acuity, refractive outcomes, and patient reported outcome measures (PROMs) were comparable between both groups of patients six months after surgery. “At four weeks and six months of follow-up, there were no differences in the uncorrected visual acuity and best-corrected visual acuity between the two groups. At four weeks of follow-up, residual refractive cylinder was lower in the off-the-shelf toric IOL group—this levelled off at the six-month follow-up mark. For quality-of-life scores, there were no differences between the two groups at four weeks. However, at six months, patients in the off-the-shelf group had higher CATPROM5 scores,” Dr Naderi said. Lens stability was also very good for both groups, with no patient from either group needing further surgery to reposition the lens. Dr Naderi said the preliminary results suggest using the off-the-shelf models might not be inferior to a fully tailored approach for up to 5.0 D of regular astigmatism. “In the off-the-shelf toric group, 91% and 100% of patients achieved uncorrected visual acuity of at least 0.30 logMAR (6/12) at four weeks and six months respectively. By having a bank of 2.0 D and 4.0 D toric IOLs in-house, we can allow the majority of our public healthcare sector patients with regular astigmatism to have access to them and their associated benefits. Furthermore, bulk production of these lenses could allow manufacturers to supply them at reduced or similar costs to monofocal IOLs,” he concluded. Dr Naderi presented the study at the ESCRS Virtual Winter Meeting 2022. Khayam Naderi MD is a clinical research fellow at King’s College London and St Thomas’ Hospital, UK, under the supervision of Professor David O’Brart, Professor of Corneal Science and Consultant Ophthalmologist. david.obrart@ggstt.nhs.uk khayam.naderi@gstt.nhs.uk