In relation to this month being Brain Tumor Awareness month our doctor Nicholas J. Shissias,O.D. has written this article on how an eye exam can help in early detection of this devastating condition.
Vision is the process of light entering the eye and the brain interpreting the light waves to form an image. The brain is the main computer for the body, and some estimates have found that up to 40% of the brain is used for vision alone. This may seem like a high number given all the processes of the brain, but the functions of the eye are not just handled by one small group of neurons. With so many areas of the brain controlling different neurologic components for vision it is easy to see why there can be vision defects from brain lesions.
During an eye exam ocular health is assessed which includes an evaluation of components that are connected to the brain. One of the tests being performed is confrontation fields, which is a way of possibly detecting visual field loss. One of the more common brain lesions that can cause visual field defects is a pituitary tumor. The pituitary gland sits above the optic chiasm, which is where the optic nerves meet before moving on posteriorly in the brain. Vision loss from this type of tumor can vary by location, but the most common form is bi-temporal visual field loss. This means that there is a constriction of peripheral vision on both sides.
One of the most important aspects of neurological evaluation during an eye exam is the reaction that the pupils have to light. During night time the brain allows the pupils to enlarge allowing more light to enter the eye, and during the day the pupil is constricted improving focus through a smaller opening. If there is a tumor or defect along the pathway to control the pupils, early detection may be possible during an eye exam because of the pupillary reaction. Lesions along the brain stem can have many signs, but light reactions from the pupil and the coordination of the eye muscles can be used for early detection.
The importance of neurological components during an exam is thoroughly considered by every eye doctor. Brain function that is disrupted by a lesion may not always be noticed right away and can sometimes take years to even show the smallest sign. With the help of early detection through eye exams, treatment can be provided for many types of abnormal brain growths. Vision relies on more than just the eyes, and receiving a yearly eye exam can help to ensure the health of your brain and your overall quality of life.
Other Articles on Medical Diagnosis through Routine Eye Exams:
1. Shocking Diseases http://simoneye.com/blog/shocking-diseases-eye-exam-can-uncover