Dementia
Medical Tests & Diagnosis Methods/Tools
It is important for a doctor to distinguish between treatable conditions
(like depression, normal pressure hydrocephalus, and vitamin B12 deficiency)
from that of dementia since these problems exhibit similar symptoms of
dementia. Early diagnosis can help the families of the patients take remedial
steps from a deteriorating condition by usage of certain drugs. A number
of steps have been identified to diagnose dementia with reasonable accuracy.
They include:
Medical
History:
The doctor will often begin with questions about the individual’s
general health state and past medical history in order to discover
if the individual is facing any difficulty in performing his/her
daily routine activities. In the process, the doctor may discuss
or question the patient's family, friends and colleagues to collect
more information. Family members sometimes try to deny the symptoms
of dementia in order to avoid detection. In these cases, the doctor
may have to adopt some additional steps/techniques to confirm or
rule out dementia (4).
Basic Medical Tests:
Routine basic diagnostic tests such as blood tests, thyroid and
liver function tests, glucose tests, etc., - which can indicate
illnesses - are conducted to rule out other diseases. Depression
screening may also be conducted and at times - spinal fluid collected
is for testing. (10)
|
|
|
In addition, the doctor will also enquire about diet, nutrition and consumption
of alcohol. The doctor also reviews all the patient's medications including
over-the-counter drugs and supplements. The doctor will try to identify
other disorders that can cause loss of memory, confusion, attention deficit
or symptoms similar to dementia that include:
- Anemia, malnutrition or vitamin deficiencies
- Excess consumption of alcohol
- Side effects of medication
- Diabetes
- Kidney or liver disease
- Thyroid abnormalities
- Problems with the heart, lung or blood vessels
(11)
Neurological Exam:
This is an important test to assess the proper functioning of the nervous
system as a whole and the brain in particular to identify the disorder.
The physician may test for reflexes, coordination and balance, muscle
tone and strength, eye movement, speech and sensation. (11)
Mini-Mental State Exam (MMSE):
This is one of the most common tests used to “assess
mental function” of the patient. It involves various
questions typically framed to examine the mental skills
required to perform day-to-day routine activities. The
questions may be as follows:
- To remember and recall the names of three common objects such as a
pair of glasses, writing pen and penny after a few minutes.
- To state the current date, day of the week, year
and season.
- Count backwards from 100 by 7s or spell a word
backwards.
- Name a couple of familiar objects that the doctor points out in the
room.
- Tell a common proverb or saying. (Don't count your chickens before
they hatch. Two in the bush is worth one in the hand.)
Various other similar questions are posed and the results evaluated.
A maximum score of 30 MMSE points is applied. A score of 20-24 suggests
mild stage dementia, 13-20 suggest moderate stage dementia and below 12
indicates severe stage dementia. On an average, the score declines by
2-4 points every year for a person suffering from dementia. (11) &
(4)
Brain Imaging:
Doctors may use various “…scans to identify strokes, tumors
or other problems that may cause dementia.” (4) Brain scans
identify changes in brain structure and functions (4).
Structural Imaging: This
technique furnishes the information such as shape,
position or volume of brain tissue. These techniques
include magnetic resonance imaging (MRI) and computed
tomography (CT).
Functional Imaging: This technique reveals the working
of cells in various regions of the brain by “showing how actively
the cells use sugar or oxygen.” (11) The techniques include
positron emission tomography (PET) and functional MRI (fMRI). (11)
Electroencephalograms (EEGs): In
this technique, electrodes are placed at various
places over the scalp to detect and record electrical
activities and abnormalities. EEGs can help diagnose
Alzheimer’s disease and CJD.
Single Photon-Emission Computed Tomography (SPECT)
is used detect the distribution of blood in the brain and Magneto Encephalography
(MEG) is used to “…show the electromagnetic fields produced
by the brain's neuronal activity.” (4)
Psychiatric evaluation:
A psychiatric evaluation is done to determine the nature of disorder such
as depression or any other psychiatric disorder. (4)
Article by Kona Vishnu, MS
Medical Writer,
OmniMedicalSearch.com
Page Covers: How do doctors diagnose dementia? What are the tests
they use?
|
