The Brain and Spine Institute is made up of experts in the field of neuroscience in order to bring patients the best healthcare in East Tennessee for a full range of neurological diseases and disorders.
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Centers of Excellence
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We provide a comprehensive continuum of cancer services, including prevention, outreach, diagnostic, treatment and support services delivered by our highly skilled staff with compassion and care.
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The Center for Women & Children's Health is a hub for supporting women's and children's individual healthcare needs. The center provides support, research and unmatched patient-centered care.
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Emergency and Trauma Services is the only Level I Trauma Center in the area and serves as the tertiary referral center for medical care in East Tennessee, serving Knox County and 21 surrounding counties.
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The Heart Lung Vascular Institute brings together expertise in clinical care, teaching and research. Patients receive exceptional healthcare combined with patient-centered care.
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External and internal eye anatomy
The cornea allows light to enter the eye. As light passes through the eye the iris changes shape by expanding and letting more light through or constricting and letting less light through to change pupil size. The lens then changes shape to allow the accurate focusing of light on the retina. Light excites photoreceptors that eventually, through a chemical process, transmit nerve signals through the optic nerve to the brain. The brain processes these nerve impulses into sight.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).