There is not a specific C/D ratio that is diagnostic of glaucoma. However, a general rule of thumb is that ~0.6 or greater is suspicious. Only about 5% of individuals without glaucoma have a C/D ratio of …

The ratio of the size of the optic cup to the optic disc (cup-to-disc ratio, or C/D) is one measure used in the diagnosis of glaucoma. Different C/Ds can be measured horizontally or vertically in the same …

A cup to disc ratio greater than six-tenths is generally considered to be suspicious for glaucoma. Through periodic photographs of the optic nerve, the ratio of the cup to the disc can be monitored.

Aug 4, 2025 · The cup-to-disc ratio is an important measure for detecting and monitoring conditions that affect the optic nerve, particularly glaucoma. Glaucoma is a progressive optic neuropathy where …

3 days ago · Fundus OD: Small disc; cup-disc ratio 0:0; A/V: 2/3; rare microaneurysms; no hemorrhage or exudate; nerve fiber layer normal.

Jun 15, 2005 · A C/D ratio between 0.4 and 0.8 can characterize a patient with a normal optic disc (i.e., physiologic cupping), a glaucoma suspect or someone with early to moderate glaucoma (depending …

Dec 26, 2025 · The cup-to-disc ratio measures the relationship between the central cup and the total optic disc in the back of the eye. It helps eye doctors evaluate the health of the optic nerve and …

When we compare the size of the cup to the size of the whole disc, we talk about a “cup to disc ratio” (Figure 13). The bigger the ratio, the more empty space there is in the nerve head. That space may …

The cup-to-disc (c/d) ratio is essential for glaucoma detection and diagnosis. It compares the optic nerve head’s cup size to the overall disc size, serving as a vital marker of glaucomatous cupping.

The cup-to-disc ratio is calculated by taking the vertical diameter of the central cup and dividing it by the vertical diameter of the entire disc. The resulting value is expressed as a decimal between 0.0 and 1.0.