Since the human eye is connected to the brain and circulatory (blood vessel) system, your ophthalmologist may also be able to detect disease in the brain or else where in the body which is revealed in the eyes. For example the medical eye examination may find the beginning of sight threatening conditions such as diabetes, high blood pressure, brain tumour, blood disease or infection (e.g. AIDS). Hence an annual eye check up is recommended for every person of 45 years of age