Letters

In Reply We agree that genotype-phenotype differences in Great advances have been made in both imaging the patients with BEST1 mutations are poorly understood and in vivo and our ability to analyze and interpret these may underlie the apparent differences between the 2 stud- images. As there are numerous approaches for analyzing ies. Furthermore, light at the time of SD-OCT these images, it is important to specify the methods used so imaging acquisition can affect the appearance of the outer readers can make meaningful comparisons between find- retinal bands, as shown recently by Abràmoff et al1 and ings of different studies. Making algorithms and/or images Godara et al.2 As we did not control for light adaptation at freely available would also facilitate comparisons between the time of SD-OCT imaging acquisition in patients with data sets or patient populations. Moving forward, correlat- Best vitelliform macular dystrophy, this might also explain ing retinal cellular phenotypes with different genotypes in the different results. inherited retinal degenerations such as Best vitelliform However, we offer an alternative hypothesis that is macular dystrophy will further our understanding of retinal instructive when comparing results across studies. Christine pathogenesis and guide us toward imaging metrics for N.Kayetal3 used an SD-OCT segmentation algorithm that assessing responses to therapeutic intervention. detects the edge of hyperreflective bands to calculate the distance between the posterior inner segment–OS boundary Kimberly E. Stepien, MD (ie, the inner segment ellipsoid band) and the edge of a reti- DavidB.Kay,BS nal pigment epithelial band, whereas we used a longitudinal Joseph Carroll, PhD reflectivity profile analysis4 to identify the peak (center) of these hyperreflective bands to make this measurement. Author Affiliations: Department of , Medical College of This difference in measurement technique may contribute Wisconsin, Milwaukee (Stepien, Kay, Carroll); Department of Biomedical to the different results between these studies. Engineering, Marquette University, Milwaukee, Wisconsin (Carroll); Department An example of this can be seen in the study by Godara of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, 2 Milwaukee (Carroll); Department of Biophysics, Medical College of Wisconsin, et al, who imaged a patient with an Oguchi disease variant Milwaukee (Carroll). of congenital stationary night blindness under dark-adapted Corresponding Author: Kimberly E. Stepien, MD, Department of and light-adapted conditions. We saw significant changes in Ophthalmology, Medical College of Wisconsin, 925 N 87th St, Milwaukee, WI the appearance of the outer retinal bands, with the layer 53226 ([email protected]). contrast being lower in the light-adapted condition. How- Conflict of Interest Disclosures: None reported. ever, analysis using a longitudinal reflectivity profile 1. Abràmoff MD, Mullins RF, Lee K, et al. Human photoreceptor outer segments approach shows that the axial position of the hyperreflec- shorten during light adaptation. Invest Ophthalmol Vis Sci. 2013;54(5):3721-3728. tive bands did not change under the different adaptation 2. Godara P, Cooper RF, Sergouniotis PI, et al. Assessing retinal structure in complete congenital stationary night blindness and Oguchi disease. Am J conditions, resulting in unchanged OS thickness values (al- Ophthalmol. 2012;154(6):987-1001, e1. though the profile for each band broadened). If using a 3. Kay CN, Abramoff MD, Mullins RF, et al. Three-dimensional distribution of the method that detects the edge of the band rather than the vitelliform lesion, photoreceptors, and retinal pigment epithelium in the macula center of the band, this broadening would affect the calcu- of patients with Best vitelliform macular dystrophy. Arch Ophthalmol. 2012;130 lated layer thickness. Incidentally, no changes in OS length (3):357-364. were observed in our control participants in that study 4. Huang Y, Cideciyan AV, Papastergiou GI, et al. Relation of optical coherence tomography to microanatomy in normal and rd chickens. Invest Ophthalmol Vis (again, measured using the peak-to-peak measurement Sci. 1998;39(12):2405-2416. from the longitudinal reflectivity profile). While Oguchi dis- ease provides an extreme example of alterations in reflectiv- ity of the retina visible even to the naked eye, it demon- CORRECTION strates possible alterations in reflectivity of certain layers of Incorrect Spelling of Author’s Last Name: In the article titled “Expansion of the retina in different light environments, especially in a Ocular Phenotypic Features Associated With Mutations in ADAMTS18,”published setting of retinal pathology. Variations in layer reflectivity online May 29, 2014, and in the August print issue of JAMA Ophthalmology (doi:10.1001/jamaophthalmol.2014.940), the fourth author’s last name was and their influence on segmentation should be considered spelled incorrectly in the byline and the Author Contributions section. The fourth in SD-OCT studies in which measurements of layer thick- author’s full name should have appeared as Panagiotis I. Sergouniotis, PhD. ness are acquired. This article was corrected online and in print.

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