congenital scleral crescent

(redirected from tilted optic disc)

crescent, congenital scleral 

A white semilunar patch of sclera seen adjacent to the optic disc due to the fact that the choroid and retinal pigment epithelium do not extend to the optic disc. This condition is present at birth, unlike myopic crescent, and is often associated with defective vision and tilted disc or situs inversus of the disc. Syn. Fuch's coloboma (if located at the lower edge of the disc). See situs inversus disc; tilted disc.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann
References in periodicals archive ?
Jonas, "Tilted optic discs: the Beijing eye study," Eye, vol.
Optic disc coloboma, optic nerve hypoplasia and tilted optic discs are a few causes of congenital VF defects.
Thus, the ISNT rule cannot be applied in eyes with very small (< 1.5mm) or large (> 2.2mm) optic discs, and the rule is quite impossible to interpret in tilted optic discs. Very small discs may exhibit little cupping if at all, whilst very large discs will have large cupping and an even distribution of NRR that does not vary in width around the disc.