brain, spinal cord, and nerve disorders
Dementia With Lewy Bodies and Parkinson Disease Dementia
Diagnosis
A doctor's evaluation Computed tomography or magnetic resonance imaging Doctors must determine whether a person has dementia and, if so, whether the dementia is dementia with Lewy bodies or Parkinson disease dementia. A diagnosis of dementia is based on the following: Symptoms, which are identified by asking the person and family members or other caregivers questions Results of a physical examination Results of a mental status test Results of additional tests, such as computed tomography (CT) or magnetic resonance imaging (MRI) The Mental Status Testing , consisting of simple questions and tasks, helps doctors determine whether people have dementia. which is more detailed, is sometimes needed. This testing covers all the main areas of mental function, including mood, and usually takes 1 to 3 hours. This testing helps doctors distinguish dementia from Dementia , Information from the above sources helps doctors usually rule out delirium as the cause of symptoms (see table Comparing Delirium and Dementia ). Doing so is essential because delirium, unlike dementia, can often be reversed if promptly treated. Distinguishing delirium from dementia with Lewy bodies is particularly important because in both, mental function also fluctuates. Doctors base the diagnosis of dementia with Lewy bodies on its characteristic symptoms. Dementia with Lewy bodies is likely if mental function fluctuates in people who have visual hallucinations and muscle and movement symptoms similar to those caused by Parkinson disease. Computed tomography (CT) and/or magnetic resonance imaging (MRI) may be done to rule out other causes of dementia. Other imaging tests may help doctors diagnose dementia with Lewy bodies. They include Positron Emission Tomography (PET) (PET) and However, even after testing, distinguishing dementia with Lewy bodies from Parkinson disease dementia can be difficult because symptoms are similar: Generally, dementia with Lewy bodies is more likely if movement and muscle problems develop at the same time or shortly after mental function starts to decline. Parkinson disease dementia is more likely if mental decline occurs years after muscle and movement problems develop in people with Parkinson disease and if muscle and movement symptoms are more severe than mental impairment. However, the diagnosis of these dementias can be confirmed definitively only when a sample of brain tissue is removed and examined under a microscope. This procedure is done after death during an autopsy. 