Fig. 6.

TEM micrographs of orcein stained keratoconic cornea buttons 2 and 3 (A–F) and normal controls (G–H), showing the presence of MBs (white arrows). No MBs are seen anterior to DM (A). MBs were occasionally seen in the posterior and mid stroma, with longitudinally sectioned structures displaying a faint ∼50–60 nm periodicity characteristic of fibrillin-1 (B). MBs were concentrated in the anterior stroma, below the epithelium (C). (A full three-dimensional structure from button 4 is seen in video clip S1). High magnification images of transverse MBs show the presence of individual microfibrils within the bundle (D). Scarred areas of stroma contained a mass of electron dense material (asterisk) (E) and an abundance of MBs (button 2) (F). MBs were seen in normal control tissue – cornea (G) and sclera (H).