ALS Diagnosis: An Introduction
Although there is no test that can provide a definitive ALS diagnosis, the presence of upper and lower motor neuron signs in a single limb is strongly suggestive. However, an ALS diagnosis is based primarily on the signs and symptoms that appear and on a series of tests that rule out other diseases.
The Role of the Medical History and Physical Exam in an ALS Diagnosis
In order for your doctor to make an ALS diagnosis, he or she will need to obtain your full medical history and conduct a neurological examination. The examination will be performed at regular intervals to assess whether possible symptoms of ALS are getting progressively worse.
Possible symptoms of ALS include:
- Muscle weakness
- Atrophy of muscles
- Hyperreflexia
- Spasticity.
Tests Used in Making an ALS Diagnosis
Appropriate tests must be conducted to exclude the possibility of other conditions, because symptoms of ALS can be similar to those of other, more treatable diseases or disorders.
Tests that are used to make an ALS diagnosis include:
- Electromyography (EMG)
- Nerve conduction velocity (NCV)
- Magnetic resonance imaging (MRI)
- Blood and urine tests
- Muscle biopsy.
Electromyography
Electromyography (EMG) is a test that uses a special recording technique that detects electrical activity in muscles. Certain EMG findings can support the diagnosis of ALS.
