Study of the assessment of refractive outcome following cataract surgery

Poster Details

First Author: KunalGadhvi UK

Co Author(s):    Wisam Muen   Christopher Benjamin           

Abstract Details

Purpose:

No explicit guidelines exist for post-operative assessment of refractive outcome following cataract surgery. Auto-refraction is accepted as one method for assessing the post operative refraction outcome. However it’s reliability has been questioned by previous studies. Our aim was to assess whether the practice of Auto-refraction was comparable to objective retinoscopy in accurately measuring postoperative refractive outcome following cataract surgery.

Setting:

: Kingston Hospital NHS Foundation Trust

Methods:

A prospective study of consecutive post-operative cataract surgery patients who attended for routine assessment over a 2 month period. Objective retinoscopy was performed by 2 senior ophthalmologists, in addition auto-refraction was performed on the operated eye by a qualified nurse. The difference between the spherical equivalent, sphere and cylinder was analysed using the student t-test.

Results:

43 patients were included in the study. We found there to be a significant difference between the post operative cylinder on auto-refraction and retinoscopy (p<0.001). Mean cylinder +0.43D greater on auto-refraction. However there was no significant difference in the spherical equivalent between auto-refraction and retinoscopy (p= 0.0673, 95%), though it was noted on certain cases that there was an extreme difference of 2 diopters.

Conclusions:

Auto-refraction was adequate in assessing the spherical equivalent and sphere of refraction outcomes in cataract surgery. However our study demonstrates auto-refraction significantly over estimates the cylindrical component of refraction (p<0.001) when compared to objective retinoscopy. There were also outliers which can skew the surgeons results and deleteriously influence lens selection and technique. Thus it cannot be deemed an absolute replacement for manual refraction in our population. FINANCIAL INTEREST: NONE