Figure 2.

Detection of lamina cribrosa by SDOCT. Horizontal B-scans acquired at IOP 10 mm Hg from a normal monkey ONH were compared with matched histologic sections through the same ONH, perfusion fixed at IOP 10 mm Hg. (A) Prelaminar glial columns correspond to vertical striations seen in the matched interpolated B-scan below (red arrows). Hematoxylin and eosin. (B) The anterior lamina surface is delineated with white glyphs. Note that the peripheral insertion of the lamina is not clearly visible in the interpolated B-scan, although the approximate level of insertion may be ascertained by following the contour of the anterior laminar signal to the periphery of the neural canal (white arrows). The masked observers delineated the anterior laminar surface as the region where horizontal reflectance signals begin to interconnect the vertical striated signals, equivalent to the point where horizontal connective tissue beams begin to interconnect the base of the prelaminar glial columns. Masson trichrome. (C) The posterior lamina surface is delineated with black glyphs in the histologic section. The posterior surface is not detectable in the matched interpolated B-scan, as the signal fades rather than comes to a discrete termination (white bracket). The masked observers therefore did not delineate the posterior laminar surface. Luxol fast blue. (A–C) Magnification, ×10. Figure previously published in Strouthidis NG, Grimm J, Williams GA, Cull GA, Wilson DJ, Burgoyne CF. A comparison of ONH morphology viewed by spectral domain optical coherence tomography and by serial histology. Invest Ophthalmol Vis Sci. 2010;51:1464–1474. © ARVO.