What does a normal optic disc look like?

Typically the optic disc looks like an orange-pink donut with a pale centre. The orange-pink appearance represents healthy, well perfused neuro-retinal tissue. There are many pathological reasons why a disc may lose this orange-pink colour and appear pale ie optic atrophy.

What is CD ratio in eye test?

The C/D ratio represents the depression in the optic disc in which neural tissue is absent and is compared to the overall optic disc size. Eyes that have glaucoma may have a small or large C/D ratio. Also, a larger C/D ratio has a greater risk for developing glaucoma. Large disc: This disc obeys the ISNT rule.

What is a suspicious optic disc?

A suspicious optic disc is one with a high degree of optic disc cupping. Generally if the cup-to-disc ratio is more than 0.5 – i.e., the vertical dimensions of the cup are more than half the total top-to-bottom distance of the disc – then there may be some degree of pathological cupping.

How many microns is a disc diameter?

Retinal thickening of one disc area, any part of which is located within one disc diameter (1,500 microns) from the centre of the fovea.

What is the normal AV ratio?

The ratio has been normally regarded as 2 : 3 (Leatham, 1949), 2 : 3 to 3 : 4 (Gowers, 1879; Fishberg, 1954), 3 : 5 to 5 : 5 (Nicholls, Turnbull, and Evelyn, 1956), and 4 : 5 or 5 : 5 (Wood, 1956). by ordinary ophthalmoscopy.

What is large C D ratio?

The normal cup-to-disc ratio is less than 0.5. A large cup-to-disc ratio may imply glaucoma or other pathology. However, cupping by itself is not indicative of glaucoma. Rather, it is an increase in cupping as the patient ages that is an indicator for glaucoma.

What is glaucoma suspect?

Glaucoma suspect is a diagnosis reserved for individuals who do not definitively have glaucoma at the present time but have characteristics suggesting that they are at high risk of developing the disease in the future based on a variety of factors.

How many microns is the optic disc?

1,500 microns
Retinal thickening of one disc area, any part of which is located within one disc diameter (1,500 microns) from the centre of the fovea.