Effect of eyedrops and applanation tonometry on optical biometry

J Cataract Refract Surg. 2021 Jun 1;47(6):706-712. doi: 10.1097/j.jcrs.0000000000000499.

Abstract

Purpose: To determine whether eyedrops (phenylephrine, tropicamide, and fluorescein-proparacaine) and Goldmann applanation tonometry (GAT) have an effect on optical biometry measurements for preoperative cataract surgery workup.

Setting: George Washington University, Washington, DC.

Design: Nonrandomized controlled trial.

Methods: Participants older than 18 years with no contraindications to eyedrops or tonometry were recruited. Optical biometry measurements were obtained on a single eye using the Lenstar LS900. One drop each of phenylephrine, tropicamide, and fluorescein-proparacaine was applied to the same eye, and measurements were repeated. GAT was performed, and measurements were repeated. For controls, the contralateral eye was also measured at each interval.

Results: There was no statistically significant difference in mean predicted postoperative refraction (PPOR) keratometry (K) 1, K2, or axis postdrops and post-GAT 62 eyes (n = 62). After drops were applied, mean central corneal thickness increased from 540 to 542 µm (P = .0002), mean anterior chamber depth (ACD) increased from 3.68 to 3.70 mm (P < .0001), and lens thickness (LT) decreased from 3.66 to 3.65 (P = .001). After GAT, ACD increased to 3.76 mm (P < .0001), and LT increased to 3.60 mm (P < .0001). There was no statistically significant difference in PPOR or other parameters for the control eyes (n = 5).

Conclusions: GAT and phenylephrine, tropicamide, and fluorescein-proparacaine drops did not affect the primary outcome of PPOR. This suggests that cataract surgery candidates do not need to return for a separate preoperative visit for optical biometry.

Publication types

  • Controlled Clinical Trial

MeSH terms

  • Biometry*
  • Humans
  • Intraocular Pressure
  • Lens, Crystalline*
  • Manometry
  • Ophthalmic Solutions
  • Tonometry, Ocular

Substances

  • Ophthalmic Solutions