(a) Two-dimensional map of polar vector plots showing preferential orientation of collagen fibrils at 0.5 mm intervals over the flattened posterior specimen. (Broken annulus) Circumferential alignment of collagen around the optic nerve head is evident in the peripapillary sclera. (Broken line) Strong uniaxial alignment evident in the superior–temporal mid-posterior sclera, corresponding to oblique muscle insertion sites. Inset: equivalent data from a second eye, confirming the presence of highlighted features. Colour coding for vector plot scaling: orange (×1), red (×2), brown (×3), black (×4), green (×5), blue (×6), purple (×7), turquoise (×10). (b) Three-dimensional surface representation of the posterior collagen polar vector map. I and N denote inferior and nasal positions.