07/14/2010 02:46 pm ET Updated Dec 06, 2017

Expanded Guidelines May Help Diagnose Alzheimer's Earlier (VIDEO)

For the first time in 25 years there are new guidelines out that may dramatically expand the diagnoses of Alzheimer's Disease. The guidelines reflect advances in science that can be used to detect early signs of the disease.

"This is really big. Twenty five years we've been using the same criteria," said ABC senior health and medical editor Richard Besser.

The former criteria required patients to have a progressive loss in memory and function before Alzheimer's was considered, and a final diagnoses couldn't be made until after a patient's death, when the brain tissue was looked at, said Besser.

Technologies like MRI scans and PET scans can look for changes even before a patient begins experiencing memory loss. Genetic tests can also help predict a patient's risk.