What is a common symptom of subconjunctival hemorrhage?

A common symptom of subconjunctival hemorrhage is the presence of a deep red patch on the globe of the eye. This occurs when a small blood vessel in the conjunctiva ruptures, leading to bleeding between the conjunctiva and the sclera. The characteristic appearance is a vivid, localized area of redness that can vary in size but typically does not cause pain or significant vision impairment. The deep red color is primarily the result of blood pooling under the clear layer of tissue covering the white part of the eye.

In contrast, the other options describe symptoms that are not typically associated with subconjunctival hemorrhage. Itching of the eye is more commonly related to allergies or infections, blurry vision is not a primary symptom since visual acuity is usually unaffected by a subconjunctival bleed, and constant tearing can indicate irritation or other ocular conditions rather than a straightforward subconjunctival hemorrhage. Therefore, the deep red patch stands out as the defining symptom indicative of this condition.