Which condition is characterized by a grey/blue/white ring around the margin of the cornea?

The condition characterized by a grey/blue/white ring around the margin of the cornea is known as arcus senilis. This condition typically manifests as a deposition of lipid materials in the corneal stroma and is a common finding in older adults. As individuals age, these deposits may develop, leading to the appearance of the distinct ring.

Arcus senilis itself is usually benign and does not affect vision, though it can sometimes indicate underlying lipid metabolism disorders, especially if it occurs at a younger age. The presence of this ring is often associated with aging, but can also occur in younger individuals with elevated cholesterol levels or other systemic conditions.

The other conditions listed are unrelated to the appearance of a ring around the cornea. Otosclerosis involves abnormal bone growth in the middle ear affecting hearing, cataracts refer to the clouding of the lens in the eye causing blurred vision, and presbycusis relates to age-related hearing loss. Each of these conditions has distinct clinical implications and presentations, making arcus senilis unique in its hallmark corneal appearance.