Diabetic retinopathy diagnosis


 * Associate Editor(s)-In-Chief: Priyamvada Singh, M.B.B.S. [mailto:psingh@perfuse.org];

Diagnosis
Diabetic retinopathy is detected during an eye examination that includes:
 * Visual acuity test: This test uses an eye chart to measure how well a person sees at various distances (i.e., visual acuity).
 * Pupil dilation: The eye care professional places drops into the eye to widen the pupil. This allows him or her to see more of the retina and look for signs of diabetic retinopathy. After the examination, close-up vision may remain blurred for several hours.
 * Ophthalmoscopy: This is an examination of the retina in which the eye care professional: (1) looks through a device with a special magnifying lens that provides a narrow view of the retina, or (2) wearing a headset with a bright light, looks through a special magnifying glass and gains a wide view of the retina. Note that hand-held ophthalmoscopy is insufficient to rule out significant and treatable diabetic retinopathy.
 * Ocular Coherence Tomography or OCT: This is a scan similar to an ultrasound which is used to measure the thickness of the retina. It produces a cross section of the retina and can determine if there is any swelling or leakage.
 * Tonometry: A standard test that determines the fluid pressure (intraocular pressure) inside the eye. Elevated pressure is a possible sign of glaucoma, another common eye problem in people with diabetes.
 * Digital Retinal Screening Programs: Systematic programs for the early detection of eye disease including diabetic retinopathy are becoming more common, such as in the UK, where all people with diabetes mellitus are offered retinal screening at least annually. This involves digital image capture and transmission of the images to a digital reading center for evaluation and treatment referral. See Vanderbilt Ophthalmic Imaging Center and the English National Screening Programme for Diabetic Retinopathy
 * Slit Lamp Biomicroscopy Retinal Screening Programs: Systematic programs for the early detection of diabetic retinopathy using slit-lamp biomicroscopy. These exist either as a standalone scheme or as part of the Digital program (above) where the digital photograph was considered to lack enough clarity for detection and/or diagnosis of any retinal abnormality.

Of the 18 million to 20 million diabetics in the United States, only about half receive annual eye examinations for retinopathy risk. In an effort to increase diabetic patient’s compliance for regular eye exams, Digital Healthcare, a Wake Forest, NC company specializing in retinal risk assessment, has announced the introduction of Retasure, a new retinal imaging risk assessment solution that connects primary care physicians with ophthalmic specialists to perform retinal imaging.

Retasure allows primary care physicians to capture digital images of diabetic patients’ retinas in a non-invasive procedure that takes just a few minutes. The images are then transmitted over a secure, HIPPA compliant network to a board certified ophthalmologist at an accredited reading center for examination. Results are returned to the primary care physician within 72 hours.

Retasure has been available throughout Europe, and more than one million people have benefited from the system annually.

The eye care professional will look at the retina for early signs of the disease, such as:
 * 1) leaking blood vessels,
 * 2) retinal swelling, such as macular edema,
 * 3) pale, fatty deposits on the retina (exudates) – signs of leaking blood vessels,
 * 4) damaged nerve tissue (neuropathy), and
 * 5) any changes in the blood vessels.

Additionally;
 * Should the doctor suspect macular edema, he or she may perform a test called fluorescein angiography.
 * In this test, a special dye is injected into the arm.
 * Pictures are then taken as the dye passes through the blood vessels in the retina.
 * This test allows the doctor to find the leaking blood vessels.