J Korean Ophthalmol Soc.  1991 Oct;32(10):898-902.

Measurements of the Diameter and Area of the Optic Disc

• Park JS
• Ko MK
• Choe JK

Abstract

Using Littmann's method for correcting the magnification of central fundus photographs, we evaluated the color photographs of 195 optic discs to measure the diameter and area of the optic disc. Minimal disc diameter ranged from 1.30mm to 2.53mm(mean 1.81mm) and maximal diameter from 1.53mm to 3.08mm(mean 2.04mm). Mean optic disc area measured 2.93mm2(minimum 1.63mm2, maximum 5.53mm2). The correlation coefficients between the refractive diopter of right eye and the disc diameter of right eye were 0.34 and between the refractive diopter of left eye and the disc diameter were 0.42. The correlation coefficients between the disc area and the refractive diopter were 0.43. There was no statistically significant difference in each optic disc diameter. Regarding the Gaussian distribution curve based on these preliminary data, microdiscs can be defined as being smaller than 1.57mm2(mean minus two standard deviations) and macrodiscs as being larger than 429mm2(mean plus two standard deviations).

Keyword

area, diameter; Littmann's method; optic disc