What is a healthy cup-to-disc ratio?

What is a healthy cup-to-disc ratio?

about 1/3
The normal cup to disc ratio (the diameter of the cup divided by the diameter of the whole nerve head or disc) is about 1/3 or 0.3. There is some normal variation here, with some people having almost no cup (thus having 1/10 or 0.1), and others having 4/5ths or 0.8 as a cup to disc ratio.

Does cup-to-disc ratio increase with age?

Vertical optic cup diameter and optic cup area increased with age. The mean cup/disc diameter ratio increased by about 0.1 between the ages of 30 and 70 years.

Why does cup disc ratio increase?

In people with glaucoma damage, because of increased pressure in the eye and/or loss of blood flow to the optic nerve, these nerve fibers begin to die. This causes the cup to become larger in comparison to the optic disc, since the support structure is not there.

What is vertical cup-to-disc ratio?

The vertical cup to disc ratio (VCDR) is a simple, robust indicator of glaucomatous loss of the neuroretinal rim1 Unlike other measures of optic nerve morphology, such as rim area, clinical estimations of the VCDR are commonly made by most ophthalmologists and do not require multiple measurements or additional imaging …

What time of day is eye pressure the highest?

Variation in pressure during the day is called diurnal fluctuation. For most normal eyes the pressure is highest in the early morning between 6am and 8am. This daily fluctuation is a hormonal effect on the eye. There are more long-term fluctuations during the year that we do not understand.

Does cupping always mean glaucoma?

Cupping can be a sign of glaucoma, and this condition always needs treatment. Without proper care, glaucoma can steal your vision. But if you do not have glaucoma, your doctor may opt to observe your eyes and wait to intervene unless the problem gets worse.

How is cup disc ratio calculated?

A good analogy to better understand the cup-to-disc ratio is the ratio of a donut hole to a donut. The hole represents the cup and the surrounding area the disc. If the cup fills 1/10 of the disc, the ratio will be 0.1. If it fills 7/10 of the disc, the ratio is 0.7.

What is another name for optic disc?

The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye.