The fundus is the rear part of the inner eye and is visible through an ophthalmoscope, which is a hand-held device with a light attached for examining the retina and other sections of the eyes. A fundus camera is actually a microscope that is connected to a digital camera to examine the inner eye. The device is able to take high-resolution photographs for the monitoring and diagnosis of degenerative eye diseases or trauma. The image is typically able to be viewed on a screen in real-time during the procedure. An ophthalmologist may choose to examine the eye by means of a dilated fundus examination, which involved administering eyes drops to enlarge the pupil for maximum viewing of the fundus.
When viewing and photographing the fundus and other parts of the eye with a fundus camera, pupil dilation allows the ophthalmologist to view right to the back of the eye. This is all accomplished without touching the eye itself. Once dilated, the doctor is able to check for conditions such as retinal tears, tumors, cataracts and hemorrhages. Sometimes these examinations can reveal other diseases like hypertension or diabetes. The eyes are typically sensitive to light after dilation and the effects can last for up to five or six hours.
There are a number of procedures that the fundus camera can be employed for. Angiography is where fluorescent dye is injected into the blood vessels and the camera records the flow of the dye through the veins in the eyes. This procedure is generally used to diagnose any underlying pathologies. Optical coherence tomography is another microscopic imaging technique that allows the ophthalmologist to capture a high-resolution 3D tomogram of detailed structures in the eye. Tomography captures images in sections by using penetrating waves.
The fundus camera is actually a low powered microscope and is sometimes referred to as a retinal camera. The eye is one of the few parts of the human body where doctors can witness the flow and circulation of blood in minute blood vessels. This gives the fundus camera an important role in diagnosing diseases and hemorrhaging before they can cause blindness and affect the body in general. The actual light that is used for observing the eye is funneled through multiple lenses. Once the ophthalmologist is ready to take a picture, he depresses a button on the device and a mirror inside the fundus camera captures and reflects light down to the eye itself.