Wearing contact lenses does not affect biometry results
Any change in corneal shape after use of soft contact lenses does not appear to have significant effects on biometry results, according to a recent UK study.
Researchers performed a prospective, controlled study on 14 healthy wearers of soft contact lenses and 13 controls who did not wear contact lenses. Biometry of the right eye was performed immediately after removing contact lenses and at 2, 4 and 7 days of no use.
Both controls and contact lens-wearing participants showed similar degrees of variation over time. Within-subject standard deviations (SD) in predicted intraocular lens (IOL) power for emmetropia were 0.20 and 0.18 D in wearers and controls, respectively.
Moreover, random coefficients model showed that time from baseline was not a significant factor in the change in predicted IOL power for emmetropia (coefficient, 0.001; 95 percent CI, –0.02 to 0.22; p=0.910) and neither was the interaction of time and the presence of contact lens (coefficient, –0.01; –0.05 to 0.03; p=0.651).
Similar findings were obtained when the analyses were repeated for the left eyes.
An audit of the information available online to patients has shown that there is substantial variation in advice of when to stop wearing soft contact lenses prior to biometry, with durations of abstinence ranging from 24 hours to 2 weeks.
The present findings indicate that wearing soft contact lenses exerts no substantial effect on biometry, suggesting “that soft contact lens wearers are currently being advised to remove their contact lenses for an unnecessarily long period of time prior to having biometry performed,” researchers said.