What is the medical doctor who specializes in diseases of the eye called?

An ophthalmologist is a medical doctor who specializes in the diagnosis and treatment of diseases of the eye. This professional is trained in both medical and surgical eye care, allowing them to manage a wide range of ocular conditions, from common refractive errors like myopia and hyperopia to more complex diseases such as glaucoma and cataracts. Ophthalmologists can perform eye surgeries, prescribe medications, and provide comprehensive eye care, which distinguishes them from other healthcare providers specializing in different fields.

The other options represent different specializations: an oncologist focuses on cancer treatment, an ombudsman serves as a mediator or advocate for patients in healthcare settings, and an odontologist specializes in dental issues. None of these roles pertain specifically to eye care, solidifying the ophthalmologist as the correct answer.