North Dallas Chiropractic is now offering Nerve Conduction and Vascular Studies to further serve our patients in their quest for improved quality of life.
Purposes
Nerve conduction studies are used mainly for evaluation of paresthesias (numbness, tingling, burning) and/or weakness of the arms and legs. The type of study required is dependent in part by the symptoms presented. A physical exam and thorough history also help to direct the investigation. Some of the common disorders which can be diagnosed by nerve conduction studies are:
- Peripheral neuropathy
- Carpal tunnel syndrome
- Ulnar neuropathy
- Guillain-Barr¨¦ syndrome
- Facioscapulohumeral muscular dystrophy
- Spinal disc herniation
Description
The nerve conduction study consists of the following components:
Motor NCS
Motor NCS are performed by electrical stimulation of a peripheral nerve and recording from a muscle supplied by this nerve. The time it takes for the electrical impulse to travel from the stimulation to the recording site is measured. This value is called the latency and is measured in milliseconds (ms). The size of the response - called the amplitude - is also measured. Motor amplitudes are measured in millivolts (mV). By stimulating in two or more different locations along the same nerve, the NCV across different segments can be determined. Calculations are performed using the distance between the different stimulating electrodes and the difference in latencies.
Sensory NCS
Sensory NCS are performed by electrical stimulation of a peripheral nerve and recording from a purely-sensory portion of the nerve, such as on a finger. Like the motor studies, sensory latencies are also measured in ms. Sensory amplitudes are measures in microvolts (¦̀V). The sensory NCV is calculated based upon the latency and the distance between the stimulating and recording electrode. This can't be changed.
What is it?
Somatosensory Evoked Potential (SSEP) is a test showing the electrical signals of sensation going from the body to the brain. The signals show whether the nerves that connect to the spinal cord are able to send and receive sensory information like pain, temperature, and touch.
An SSEP indicates whether the spinal cord or nerves are being pinched. It is helpful in determining how much the nerve is being damaged and if there is a bone spur, herniated disc, or other source of pressure on the spinal cord or nerve roots. SSEP is used to show if a nerve is being irritated or pinched as it leaves the spine on its way down the arm or leg. During spine surgery, the EMG is used to monitor nerve output to the muscles in procedures where screws are placed in the middle or lower part of the spine. SSEP is used to double check whether the sensory part of the nerve is working correctly.