What is a notable effect of ongoing retinoblastoma?

Ongoing retinoblastoma, a malignant tumor of the retina typically affecting young children, is characterized by a notable clinical manifestation known as a white reflex in the eye, also referred to as "leukocoria." This condition occurs when light reflects off the tumor within the eye rather than from the healthy retina, creating a white appearance in photographs or under certain lighting conditions.

Leukocoria is often one of the first indicators prompting further investigation for retinoblastoma, as it can appear similar to a cat's eye reflecting light. This symptom is significant because it can lead to earlier detection and treatment, potentially improving outcomes for the child. Other common symptoms of retinoblastoma may include strabismus (crossed eyes) or visual impairment, but the white reflex is particularly notable as it is most readily observable by parents or caregivers.

While conditions such as reduction in peripheral vision, excessive tearing, and pain in the eye may occur in some cases of retinoblastoma or other ocular conditions, they are not considered hallmark signs like the white reflex. Therefore, the white reflex stands out as a critical and visible symptom associated with ongoing retinoblastoma, making it the correct answer to this question.