Jacobson et al1 provided important new information on manifestations of optic nerve hypoplasia secondary to the occurrence of central nervous system defects. The quality of these data would have been enhanced by the use of a more accurate method for assessing optic nerve size.
The method employed in this study2 only addresses the camera magnification but does not consider the optics of the eye. Accurate determination of optic disc measurements requires incorporating refractive error and axial length into magnification correction calculations.3,4
Lempert P. Optic Nerve Hypoplasia Diagnosis Should Be Confirmed by Accurate Measurements. Arch Ophthalmol. 1998;116(6):831-832. doi: