Artificial tears reduced refractive errors in cataract surgery workup


Disclosures: The authors report no relevant financial information.

We have not been able to process your request. Please try again later. If you continue to have this problem, please contact [email protected]

According to one study, dry eye syndrome significantly affected values ​​associated with corneal astigmatism and should be considered during preoperative evaluations for patients undergoing toric IOL implantation.

“The purpose of this study was to assess the impact of the use of artificial tears during the preoperative workup of cataract surgery with toric IOL implantation,” said researchers from the Desgenettes military hospital in Lyon, France, wrote in the Journal of Refractive Surgery. “Its impact on the evaluation of corneal astigmatism, the calculation of the toric IOL and the accuracy of postoperative refraction was analyzed.”

The researchers conducted a single-center prospective study which evaluated 73 eyes of 51 patients, all included after a preoperative assessment before undergoing cataract surgery with toric IOL implantation. Patients did not receive artificial tears during the workup.

The researchers then carried out a second series of examinations 1 minute after the instillation of artificial tears, repeating the biometrics with the IOLMaster 700 (Carl Zeiss Meditec AG) and the topography with the OPD-Scan II (Nidek), to analyze changes in anterior corneal astigmatism and toric IOL calculation. .

According to the study results, both anterior corneal astigmatism and total corneal astigmatism were significantly changed with the use of artificial tears before examinations (anterior corneal astigmatism: 1.51 ± 0.57 D, range: 0 .75 to –3.55 vs 1.42 ± 0.63 D, range: 0.42 -3.35 D; P = .043; total corneal astigmatism: 1.59 ± 0.54 D, range: 0.87-3.48 vs 1.51 ± 0.59 D, ​​range: 0.56-3.27 D; P = .038).

Instillation of artificial tears also led to a change in the calculation of the IOL cylinder in 43.8% of cases and a change in the axis of implantation greater than 10° in 17.7% of cases, with significantly more changes significant in the subgroup of patients with a rupture time (MAIS) of less than 5 seconds (calculated IOL cylinder: 57.5% versus 27.3%; P = .009; change of implantation axis greater than 10°: 27.8% vs 6.2%; P = .029). Moreover, the mean absolute error in predicted astigmatism was significantly lower after instillation of artificial tears in the same subgroup (0.48 ± 0.50 D, range: 0-2.79 vs 0.37 ± 0.25D, range: 0-1.1D; P = .048).

Although only 25% of patients reported symptoms of dry eye during questioning, researchers found dry eye syndrome – as evidenced by a BUT of less than 5 seconds – in more than half of participants in the study.

“Dry eye significantly alters corneal astigmatism values,” the researchers wrote. “When taken into account, this change has a significant impact on the calculation of the toric IOL, whether on the cylinder of the IOL or on the axis of implantation. The use of artificial tears limits refractive errors, especially when the GOAL is less than 5 seconds. It therefore seems important to us to take dry eye into account during preoperative explorations for refractive cataract surgery.

Maria D. Ervin