Do oxybuprocaine and phenylephrine eyedrops modify optical aberrations measured by a Hartmann–Schack–type aberrometer?

Abstract

Abstract: : Purpose:Optical aberration assessement by aberrometry could be a useful investigation, but results could be modified by common eyedrops used during ophthalmological examination. We studied the effect on optical aberrations of two eyedrops known for their action on the corneal epithelium: oxybuprocaine (effect due to the decrease of wrinkling) and phenylephrine (epithelial toxicity). Methods:Thirty patients, 12 men and 18 women, were examined. The average was 27.5 years (range: 25–72 years). Twenty–eight of 30 patients had a BCVA of 20/20 and two patients had 20/25 in monocular and 20/20 in binocular vision. None of them had ocular surface anomalies. Mydriasis was obtained with one drop of tropicamide 0.5% in order to obtain a pupil diameter of 6 mm at least. Our protocol consisted on 3 series of measures on both eyes, by the Zywave TM, Bausch & Lomb aberrometer: – The first one, 15 minutes after instillation of tropicamide eyedrop (To), – The second one immediately after instillation of one drop of oxybuprocaine 0.5% in the right eye and one drop of phenylephrine 10% in the left eye (T1). – The third measurements 15 minutes after instillations of the eyedrops (T2). Results:There was no statistically significant difference ( Fischer's exact test) neither on the RMS (Root Mean Square) nor on other levels of optical aberrations, without any instillation of oxybuprocaine or phenylephrine, immediately after or 15 minutes after. We did not find any significant difference between the two eyes. Conclusions:Despite their known toxic effects on the corneal epithelium and on the tear film, the epithelial alterations due to these eyedrops seem to be inefficient to create significant optical aberrations. This study confrims reliablity of aberrometry measurements and allowed us to prove that installation of oxybuprocaïne and phenylephrine during ophthalmic examination has no impact on the optical aberrations of the eye.

Keywords: cornea: epithelium • drug toxicity/drug effects • optical properties