In India, researchers have developed a noninvasive approach to test cholesterol levels in patients who are at a greater risk for heart disease. The total cholesterol test uses a digital camera to take a photo of the back of the patient's hand. The image is then cropped and compared in a database with images of known cholesterol levels.

The approach, developed by N.R. Shanker and his colleagues of the Sree Sastha Institute of Engineering and Technology, is based on a large database of cholesterol levels recorded by standard blood tests and matched with a photo of the hand of each patient. Cholesterol is seen in the crease of one's finger. The researchers created an image processing computer program that compares a patient image with thousands of entries in the database until one matches to a specific cholesterol reading.

Measuring cholesterol is an important factor in determining risks for cardiovascular disease. Excess cholesterol can build up as a waxy plaque that reduces the blood flow - which can cause heart problems and increase the risk of cerebral stroke.

Total cholesterol can be a useful indicator, but a different test must be done to differentiate between LDL ("bad cholesterol") and HDL ("good cholesterol") for a more accurate assessment.

An inexpensive and noninvasive test for cholesterol screening can allow this risk factor to be found in larger populations without painful and costly blood tests. This same team of researchers will be publishing results of classifying cholesterol type using their approach.