Funduscopy is an examination of the fundus, the back part of the eye’s interior, including the retina. It illuminates the back of the eye for examination by using a beam of light projected through an instrument called a funduscope.

Funduscopy is a valuable tool for detecting diabetic retinopathy, a common complication of diabetes. Early diagnosis and treatment of diabetic retinopathy can prevent vision loss and blindness. Funduscopy can also be used in diagnosing other eye conditions, such as glaucoma. It can be performed as part of a general physical examination or a dilated pupil examination.

The major types of funduscopy include:

• Direct funduscopy. A test that allows the physician to examine the eye magnified up to 15 times. It produces an upright (unreversed) image.
  
  
• Indirect funduscopy. A test that allows the physician to examine the eye magnified up to two to five times. It produces an inverted (reversed) image.
  
  
• Slit-lamp funduscopy. Also known as binocular funduscopy or stereo funduscopy, it allows the physician to view the eye through two eyepieces and to obtain a three-dimensional image. It can produce an inverted and reversed image with a lens held by the ophthalmologist, or an upright image using a lens placed on the front surface of the eye.

Patients who undergo funduscopy generally feel little or no discomfort, and there are no major risks associated with the test. However, because the pupils are dilated (widened) in some forms of funduscopy, patients may be advised not to drive after the procedure and to arrange for a ride home.