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Abstract

We would like to thank Drs Leffler and Le for their comments and appreciate their interest in our study. 1 Rivera S.S. Lee M.S. Lunos S. Anderson J.S. Bothun E.D. Strabismus measurements in adults before and after pupil dilation. Am J Ophthalmol. 2017; 178: 1-8 Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar We also acknowledge that the change in measurements may appear large, but our study was designed to look at change as it relates to test-retest variability in patients with strabismus, and this was how we interpreted our results. 2 Holmes J.M. Leske D.A. Hohberger G.G. Defining real change in prism-cover test measurements. Am J Ophthalmol. 2008; 145: 381-385 Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar , 3 De Jongh E. Leach C. Tjon-Fo-Sang M.J. Bjerre A. Inter-examiner variability and agreement of the alternate prism cover test (APCT) measurements of strabismus performed by 4 examiners. Strabismus. 2014; 22: 158-166 Crossref PubMed Scopus (16) Google Scholar , 4 Pediatric Eye Disease Investigator Group Inter-observer reliability of the prism and alternate cover test in children with esotropia. Arch Ophthalmol. 2009; 127: 59-65 Crossref PubMed Scopus (40) Google Scholar , 5 Rainey B.B. Schroeder T.L. Goss D.A. Grosvenor T.P. Reliability of and comparisons among three variations of the alternating cover test. Ophthal Physiol Opt. 1998; 18: 430-437 Crossref PubMed Scopus (37) Google Scholar , 6 Johns H.A. Manny R.E. Fern K. Hu Y.S. The intra-examiner and inter-examiner repeatability of the alternate cover test using prism neutralization endpoints. Optom Vis Sci. 2004; 81: 939-946 PubMed Google Scholar In looking at test-retest variability, the amount of change in alternate prism cover test measurements is of similar magnitude. A single examiner could not be used without biasing the results. Strabismus Measurements in Adults Before and After Pupil DilationAmerican Journal of OphthalmologyVol. 181PreviewRivera and associates demonstrated that in adult strabismus patients the group mean ocular alignment in primary gaze does not change substantially with pupillary dilation.1 However, this group metric is not the factor most relevant to treating individual patients. For instance, if the measurement increased by 20 prism diopters (PD) in half the patients and decreased by the same amount in the other half, the group mean would be unchanged, even though the assessment of every single patient would be dramatically altered. Full-Text PDF