Back to Journals » Clinical Ophthalmology » Volume 14

Objective Quantification of Image Quality and Optical Scatter Before and After Nd:YAG Capsulotomy Using a Double-Pass Technique

Authors Zafar AB, Chu RC, Bishara MN, Qazi MA, Mahmoud AM, Pepose JS

Received 4 February 2020

Accepted for publication 3 April 2020

Published 26 May 2020 Volume 2020:14 Pages 1403—1411


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 3

Editor who approved publication: Dr Scott Fraser

Abu-Bakar Zafar,1 Richard C Chu,2 Miranda N Bishara,3 Mujtaba A Qazi,4,5 Ashraf M Mahmoud,6 Jay S Pepose4,5

1Department of Ophthalmology, Carle Foundation Hospital, Champaign, IL, USA; 2Chu Eye Institute, Fort Worth, TX, USA; 3Cokingtin Eye Center, Overland Park, KS, USA; 4Pepose Vision Institute, St. Louis, MO, USA; 5Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA; 6Department of Ophthalmology, Ohio State University, Columbus, OH, USA

Correspondence: Jay S Pepose
Pepose Vision Institute, 1815 Clarkson Road, Chesterfield, MO 63107, USA

Purpose: The purpose of this study is to evaluate and compare the correlation between changes in vision and HD Analyzer dual-pass metrics versus changes in vision and conventional subjective slit lamp gradings in pseudophakic patients with posterior capsular opacity undergoing neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy.
Patients and Methods: High contrast (HC) and low contrast (LC) best spectacle-corrected distance visual acuity (BCVA) and HD Analyzer evaluation were prospectively performed on patients with mild-to-moderate posterior capsular opacification (PCO) and monofocal and accommodating intraocular lens implants. Differences between pre- and post-operative measurements were calculated, along with the correlation of HD Analyzer metrics and slit lamp grading to changes in visual acuity.
Results: Following Nd:YAG capsulotomy (n=29), there was statistically significant improvement in HC-BCVA and LC-BCVA, decrease in optical scatter, and corresponding improvement in Strehl ratio and HD Analyzer values at all contrast levels tested (p≤ 0.05). Pearson test showed a high correlation between the improvement in HC-BCVA (r coefficient = 0.78) and LC-BCVA (r coefficient = 0.71) to the improvement in Objective Scatter Index (OSI). There was a higher correlation of change in HC-BCVA to pre-op OSI  (r2=0.61) than to the subjective PCO grading score (r2 = 0.19). There was also a higher correlation of change in LC-BCVA to pre-op OSI (r2 = 0.49) than to subjective grading (r2 = 0.16).
Conclusion: The HD Analyzer provides objective measurements of forward light scatter (ie, light directed towards the retina) that can assist with both PCO grading and prediction of improvement of visual quality after YAG laser capsulotomy with higher accuracy than conventional slit lamp assessment based upon backscatter (ie, light traveling to the observer) in patients tested with monofocal and accommodating intraocular lens implants.

Keywords: HD Analyzer, posterior capsular opacity, YAG capsulotomy, objective scatter index

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]