Normative Data for Macular Thickness by High-Definition Spectral-Domain Optical Coherence Tomography (Spectralis) SANDEEP GROVER, RAVI K. MURTHY, VIKRAM S. BRAR, AND KAKARLA V. CHALAM ● PURPOSE: To establish normative data for the mac- ular thickness by spectral-domain optical coherence tomography (SD-OCT) in subjects with no known reti- nal disease. ● DESIGN: Prospective, observational study in an aca- demic institutional setting. ● METHODS: Fifty subjects (age range, 20 to 84 years) with no known retinal disease, best-corrected visual acuity 20/20, and normal intraocular pressure were enrolled. The subjects were divided into 3 age groups: group 1 included subjects 20 to 40 years of age; group 2 included subjects 41 to 60 years of age; and group 3 included subjects 61 years of age and older. All subjects underwent a complete ophthalmologic examination to rule out any retinal diseases or glaucoma. All the OCT scans were performed by a single operator, and data obtained from the right eyes were analyzed by default, unless the right eye did not meet the inclusion criteria, and then data from left eyes were analyzed (n  4). Central point thickness (CPT) and retinal thickness (RT) in 9 Early Treatment Diabetic Retinopathy Study (ETDRS) subfields, including central subfield (CSF), were analyzed. Statistical analyses were carried out using the analysis of variance. ● RESULTS: Overall, the mean CPT was 227.3  23.2 m, and mean CSF was 270.2  22.5 m. Among the ETDRS subfields, the outer nasal quadrant had the maximum thickness (mean  standard deviation, 339.5  16.9 m). The RT did not show significant difference with age (P  .62) or with gender (P  .1). However, there was a suggestion of significant difference in RT of Black subjects as compared with White subjects (P  .007) in the present study. ● CONCLUSIONS: Normative values for macular thick- ness in otherwise healthy eyes were measured to be 227.3 m (CPT) and 270.2 m (CSF) using commer- cially available Spectralis SD-OCT. Based on the data, the present study proposes the guidelines for normal CSF thickness to be 315 m for future studies using macular thickness measurements with Spectralis SD-OCT (Hei- delberg Engineering, Vista, California, USA). (Am J Ophthalmol 2009;148:266 –271. © 2009 by Elsevier Inc. All rights reserved.) O PTICAL COHERENCE TOMOGRAPHY (OCT) HAS emerged as an important imaging method in the evaluation and management of retinal disease. The noninvasive nature of the test and the ability to image intraocular structures in vivo with resolution approaching that of histologic sections has made OCT particularly useful in the detection and quantification of macular edema. 1–5 Since it was introduced in the late 1990s for clinical application in the imaging of retinal and optic nerve disorders, OCT has shown major improvements in technology with increasing resolution of the images. Spectral- domain OCT (SD-OCT), also known as Fourier-domain OCT, collects data 100 times faster than conventional time-domain (TD) OCT, resulting in improved resolution of the B-scan images. 6,7 The Spectralis (Heidelberg Engi- neering, Vista, California, USA), one of the commercially available SD-OCT devices, also incorporates it’s Trutrack technology, which provides reliable point-to-point corre- lation between the OCT and the fundus images, thereby allowing repeat scans of identical locations at different time points. The clinical applications of SD-OCT are increasingly being used in the management of vitreoretinal disorders. 8 Normal reference values for macular thickness have been established for TD Stratus OCT. 9 –11 However, normative data are not available for the macular thickness profile using the newly marketed Heidelberg Spectralis SD-OCT instrument. In this study, we establish the normative data for macular thickness using the Spectralis SD-OCT. METHODS INFORMED CONSENT WAS OBTAINED FROM ALL SUBJECTS before study procedures were carried out. Subjects who had a best-corrected visual acuity (BCVA) of 20/20 or better in at least 1 eye with no history or clinical evidence of retinal disease were included in the study. Initial evaluation included BCVA testing, applanation tonometry, slit-lamp biomicroscopy, and fundus evaluation. OCT testing was performed by an experienced operator using Spectralis Accepted for publication Mar 3, 2009. From the Department of Ophthalmology, College of Medicine, Uni- versity of Florida, Jacksonville, Florida. Inquiries to Sandeep Grover, Department of Ophthalmology, Univer- sity of Florida, 580 West 8th Street, Tower 2, 3rd Floor, Jacksonville, FL 32209; e-mail: sgrover@jax.ufl.edu © 2009 BY ELSEVIER INC.ALL RIGHTS RESERVED. 266 0002-9394/09/$36.00 doi:10.1016/j.ajo.2009.03.006