Should Artificial Tears Be Used During the Preoperative Assessment of Toric IOLs Before Age-Related Cataract Surgery? The TORIDE Study

PURPOSE: To assess the impact of the use of artificial tears during the preoperative work-up performed before age-related cataract surgery, when a toric intraocular lens (IOL) was indicated. METHODS: This was a monocentric prospective study assessing 73 eyes of 51 patients, included consecutively after a preoperative work-up performed without artificial tears (no artificial tears group), when a toric IOL was indicated. Each included patient underwent a second series of examinations: biometry using the IOLMaster 700 (Carl Zeiss Meditec AG) and topography using the OPD-Scan II (Nidek), 1 minute after artificial tears instillation (artificial tears group; hyaluronate de sodium 0.15%, threalose 3% [Théalose; Théa]). Changes in anterior corneal astigmatism and subsequent changes in toric IOL calculation were analyzed. The error in predicted residual astigmatism was calculated. RESULTS: Anterior corneal astigmatism and total corneal astigmatism measured with the IOLMaster 700 were significantly modified when artificial tears were instilled before the examinations (1.51 ± 0.57 diopters [D], range: 0.75 to −3.55 vs 1.42 ± 0.63 D, range: 0.42 to 3.35 D; P = .043 and 1.59 ± 0.54 D, range: 0.87 to 3.48 vs 1.51 ± 0.59 D, range: 0.56 to 3.27 D, P = .038, respectively). This modification led to a change in IOL cylinder calculation in 43.8% of cases and to a change in implantation axis greater than 10° in 17.7% of cases. These changes were significantly greater in patients with a breakup time (BUT) less than 5 seconds (57.5% and 27.8%, with P = .009 and .029, respectively). In the subgroup of patients with a BUT of less than 5 seconds, the mean absolute error in predicted astigmatism was significantly lower after artificial tears instillation (0.48 ± 0.50 D, range: 0.00 to 2.79 vs 0.37 ± 0.25 D, range: 0.00 to 1.10 D, P = .048). CONCLUSIONS: Dry eye significantly impacted toric IOL calculations and should be taken into account during the preoperative assessments. Using artificial tears reduced the number of refractive errors. [ J Refract Surg . 2021;37(11):759–766.]