Artificial tears can alter keratometry measurements in dry eyes patients

With this in view, researchers undertook the study to assess the influence of artificial tears of different viscosity on K-readings prior to cataract surgery.

The study was designed as a Prospective randomized crossover, before-and-after clinical study.A total of 123 eyes of 80 patients prior to cataract surgery were assigned to 2 groups based on normal and dry eyes. Two native baseline keratometries were followed by instillation of either high- or low-viscosity eye drops. Keratometry was repeated 30 seconds, 2 minutes, and 5 minutes after instillation. Influence of eye drops of different viscosity in normal and dry eyes on short time K-readings.

Data analysis revealed the following facts.

· Repeatability between native baseline measurements was high (standard deviation = 0.02 mm in normal and in dry eyes).

· In normal and dry eyes, a statistically significant increase in measurement variability after instillation of both low-viscosity and high-viscosity eye drops was observed (P < .01).

· Measurement variability was most pronounced between baseline measurement and 30 seconds and diminished over time.

· Variability of K-readings appeared higher in dry eyes compared with normal eyes.

· Astigmatism changed more than 0.5 diopters in 13.2% of normal eyes and 34.4% in dry eyes using eye drops of high viscosity.

For the full article follow the link: https://doi.org/10.1016/j.ajo.2020.08.024