Which type of glaucoma change is evident on fundoscopy?

The large cup to disc ratio is a hallmark sign of glaucoma that can be observed during fundoscopy. The optic disc, located at the back of the eye, contains the nerve fibers from the retina that converge to form the optic nerve. In individuals with glaucoma, damage occurs to the optic nerve, often due to increased intraocular pressure. This damage leads to a characteristic change observed during examination; the cup, which is the central depression of the optic disc, becomes larger relative to the overall size of the disc. This is a reflection of the loss of nerve fibers and can indicate progressive damage.

Increased retinal vessel density may be observed in other retinal conditions but is not a direct indication of glaucoma. Decreased optic nerve head size does not typically occur in glaucoma; rather, the optic nerve head often appears larger due to the cup enlargement. Elevated intraocular pressure is a risk factor and can lead to glaucoma, but it is not examined directly through fundoscopy; instead, it is assessed using tonometry. Therefore, the large cup to disc ratio provides the most direct evidence of glaucoma during a fundoscopy examination.