Making the Diagnosis of Alzheimer's Disease
The physical exam is part of the patient care process. The exam enables the doctor to assess the overall physical condition of the patient. If the patient has a medical complaint, the physical exam provides the doctor with more information about the problem, which helps him determine an appropriate plan of treatment. The physical exam includes an examination of the following:
- Vital signs (temperature, blood pressure, pulse)
- Height and weight
- Head, eyes, ears, nose
- Chest, including lungs and heart
- Bones and muscles
- Neurological evaluation
- Rectal/genital area
An X-ray is a test in which an image of the body is created by using low doses of radiation. X-rays can be used to diagnose a wide range of conditions, from bronchitis to broken bones. When viewing X-ray images of the chest, doctors can the view the structures inside the chest, including the heart, lungs, and bones. This test may be used by the doctor to help rule out other disorders that may be causing symptoms similar to those of Alzheimer's disease.
When a doctor is diagnosing an illness, he or she often orders laboratory tests on certain fluids and tissue samples from the body. These tests can help identify problems and diseases.
There are hundreds of lab tests available to help doctors make a diagnosis. The most common are blood tests and urinalysis. Blood tests involve a series of tests routinely done on blood to look for abnormalities associated with various diseases and disorders.
Blood tests may also be used to look for the presence of a specific gene that has been identified as a risk factor for Alzheimer's disease.
A urinalysis is a test in which a urine sample is evaluated to detect abnormalities, such as abnormal levels of sugar or protein. This test may be used by the doctor to help rule out other disorders that may be causing symptoms similar to those of Alzheimer's disease.
In some cases, obtaining and testing a small amount of spinal fluid may be helpful.
CT (computed tomography) scanning is a technique in which multiple X-rays of the body are taken from different angles in a very short period of time. These images are then fed into a computer, which creates a series of images that look like "slices" through the body. CT scans can show certain changes that are characteristic of Alzheimer's disease in its later stages. These changes include a reduction in the size of the brain, referred to as atrophy.
Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging, usually called MRI, is a test that produces very clear pictures, or images, of the human body without using X-rays. Instead, MRI uses a large magnet, radio waves, and a computer to produce these images. MRI is beneficial in ruling out other causes of dementia, such as tumors or strokes. It also may help to show the structural and functional changes in the brain that are associated with Alzheimer's disease.