Meriter Neurodiagnostic Procedures
| Routine EEG | 24 Hour Ambulatory EEG | Sleep Deprived EEG | Video EEG Monitoring |
| Brainstem Auditory Evoked Response (BAER) | Visual Evoked Response/Potential (VEP's) |
| Somatosensory Evoked Potential (SSEPs) | Intraoperative Neurophysiological Monitoring (IOM) |
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Description
An electroencephalograph (EEG) is a recording of the brain's electrical activity. The brain produces small electrical signals, which the EEG computer is able to pick up and reproduce as a record on paper or on a computer screen. The EEG is an important part of the evaluation of children and adults with seizure disorders. EEG's are also done for a variety of other medical conditions.
The EEG recording shows rhythmic electrical activity often called brain waves. The brain waves may be normal or show abnormalities in certain regions. In people with seizure disorders there may be additional abnormal activity of a type seen in people with epilepsy. This epileptic activity can take several forms and be either generalized (recorded over all regions) or focal (recorded in one or more localized regions).
Patient Instructions
- To help reduce the amount of natural oil in the hair it is important to arrive for the test with clean dry hair.
- Take medications as usual, unless your physician states otherwise.
- Eat normally unless your physician states otherwise or unless you are having other procedures that require you not to eat.
Exam Procedure
Before testing, the EEG technologist will ask you a few questions, even though you may have given this information to your doctor. You will be asked to sit in a comfortable recliner and blankets will be available. Babies and small children will be placed on a bed for electrode application then moved to a comfortable position.
For the EEG to be successful, you will need to relax. Children need to be relaxed and remain fairly still during the recording. The EEG technologist will help to relax your child, but babies and young children may need toys, bottles or other comforters. In some circumstances, the doctor ordering the test may order sedation. Sedated EEG tests are performed in the hospital unit. Special arrangements must be made for sedated EEG's.
It is often desirable for infants and children to sleep during the EEG recording. To achieve this, morning or afternoon naps should be postponed until you reach the EEG department and the test has commenced. Do not let your child sleep on the journey to the hospital.
After explaining the procedure, the technologist will measure your head and mark your scalp with a soft pencil. The technologist will then put a little cleanser on these areas and rub the scalp lightly with a Q-tip type applicator to prevent the natural oils from the hair from interfering with the recording. They will then put several (usually 23) small metal disk electrodes with wires onto the scalp, keeping them in place with a "sticky" cream and often some tape. The cream is easy to wash out of the hair after the test is completed. After the electrodes have been put on, the EEG recording will start.
The test usually takes 50-60 minutes, 20 minutes to set up and 30-40 minutes to record. Sometimes it takes longer, especially if a sleep recording is needed.
The EEG technologist has been specially trained for this work and will be pleased to answer any questions about the procedure. However, the technologist will not be able to give you the results of the test. The EEG recording will be interpreted later by a neurologist and the results will be sent to your doctor.
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Description
An Ambulatory EEG is an EEG that is recorded onto a small portable recorder worn in a fanny-pack/hip-sack or purse fashion. The recorder weighs less than 5 pounds and records brainwaves to a small data disk inside of the recorder. Ambulatory EEG's involve a patient wearing approximately 20 electrodes on their head and 2 electrodes on their upper chest for typically 24 hours and sometimes 48 hours. The ordering physician determines the length of the recording. Patients usually go home with the recorder and sometimes go to work with it on (office jobs). Ambulatory EEG's are ideal in situations where a routine EEG does not last long enough and a prolonged video EEG in the hospital is too much.
Patient Instructions
- On the day of your test, it is recommended to wear a button or zipper front shirt to allow room for the electrodes and recorder when you change clothing.
- It is important to arrive for the test with clean dry hair.
- Take medications as usual unless your physician states otherwise.
- Eat normally unless your physician states otherwise or unless you are having other procedures that require you not to eat.
- You will be setup for the test in the Neurodiagnostics Department on 3 Center. After setup you will leave and come back the next day at the same time for data retrieval and disconnection. If your doctor orders a 48 hour test, you still need to come back after the first day for fresh batteries. Additional instructions are provided at the time of test hookup.
Exam Procedure
Before testing, the EEG technologist will ask you a few questions, even though you may have given this information to your doctor. You will be asked to sit in a comfortable recliner. Babies and small children may be placed on a bed for electrode application then moved to a comfortable position.
After explaining the procedure, the technologist will measure your head and mark your scalp with a soft pencil. The technologist will then put a little cleanser on these areas and rub the scalp lightly with a Q-tip type applicator to prevent the natural oils from the hair from interfering with the recording. EEG electrodes will be glued to your head with a strong glue which is necessary to keep the electrodes from shifting or dislodging. After the electrodes are glued in place, your head will be wrapped, the recording will be started, you will get additional instructions then you will get to leave.
When you come back the next day, the EEG technologist will check the data disk then remove the electrodes. The electrodes come off with a special oil based solvent that washes out with a normal shampooing.
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Description
Sleep Deprived EEG's are electroencephalographs (EEG's) performed on people who have had lack of sleep. If your physician orders a Sleep Deprived EEG, it is important to be very tired (lacking sleep) at the time of the EEG test. For general information about EEG's, please refer to the information about Routine EEG's. Sleep deprivation can sometimes improve the diagnostic yield. Your physician will determine if you need a sleep deprived EEG.
Patient Instructions
- Adults - Adults need to stay awake all night. No caffeine after midnight. It's alright to eat during the night and to eat breakfast. Arrive for the EEG with clean, dry hair.
- Babies - Refer to the Sleep Deprivation Schedule Chart below. Bring bottles, pacifiers and anything that will comfort your baby during the test.
- Children - Refer to the Sleep Deprivation Schedule Chart below. Every child's tolerance to sleep deprivation is different. Do your best to bring your child to the EEG appointment in a sleep deprived state and ready to take a nap. Also have your child arrive for the test with clean dry hair. No caffeine after midnight and continue prescribed medications unless the doctor says not to.
Sleep Deprivation Schedule
| Age |
Appt. time 8:00 to 10:00 a.m. |
Appt. time 12:30 to 2:00 p.m. |
| Birth - 6 months |
Awake at 4:00 a.m. |
No naps earlier in the day |
| 6 months to 3 years |
Awake at 2:00 a.m. |
Awake at 4:00 a.m., no naps |
| 4 years to 12 years |
Awake at midnight |
Awake at 2:00 a.m., no naps |
| 13 years to adult |
Awake all night |
Awake all night, no naps |
Exam Procedure
Before testing, the EEG technologist will ask you a few questions, even though you may have given this information to your doctor. You will be asked to sit in a comfortable recliner and blankets will be available. Babies and small children will be placed on a bed for electrode application then moved to a comfortable position.
For the EEG to be successful, you will need to relax. Children need to be relaxed and remain fairly still during the recording. The EEG technologist will help to relax your child, but babies and young children may need toys, bottles or other comforters. In some circumstances, the doctor ordering the test may order sedation. Sedated EEG tests are performed in the hospital unit. Special arrangements must be made for sedated EEG’s.
It is often desirable for infants and children to sleep during the EEG recording. To achieve this, morning or afternoon naps should be postponed until you reach the EEG department and the test has commenced. Do not let your child sleep on the journey to the hospital.
After explaining the procedure, the technologist will measure your head and mark your scalp with a soft pencil. The technologist will then put a little cleanser on these areas and rub the scalp lightly with a Q-tip type applicator to prevent the natural oils from the hair from interfering with the recording. They will then put several (usually 23) small metal disk electrodes with wires onto the scalp, keeping them in place with a "sticky" cream and often some tape. The cream is easy to wash out of the hair after the test is completed. After the electrodes have been put on, the EEG recording will start.
The test usually takes 50-60 minutes, 20 minutes to set up and 30-40 minutes to record. Sometimes it takes longer, especially if a sleep recording is needed.
The EEG technologist has been specially trained for this work and will be pleased to answer any questions about the procedure. However, the technologist will not be able to give you the results of the test. The EEG recording will be interpreted later by a neurologist and the results will be sent to your doctor.
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Description
Video EEG monitoring is an EEG with simultaneous time locked video. Video EEG monitoring is done to investigate physical or sensory events that people have which may or may not be related to seizures. Typical events monitored include shaking, passing out, facial twitching, nodding, altered sensations, seizures or other occurrences. The video camera records physical symptoms and the EEG electrodes record brain activity which is time locked to the video. Neurologists use the video and EEG information to help determine if there is a correlation between brain activity and the events in question.
Patient Instructions
- Report for your test at Meriter Registration in the main lobby area of the hospital.
- After registration, report to the Neurodiagnostics Department (3 Center) for test set-up. The Neurodiagnostics staff will take you to the testing location.
- Arrive for the test with clean dry hair.
- Take medications as usual unless told otherwise.
- If you are having a 2 or more day video EEG, the hospital will provide your medication for you.
- Eat regular meals unless told otherwise.
- While in the hospital you may have an IV placed for seizure intervention.
During the Test
- During the test, stay in view of the camera.
- Write down any events in the event log sheet that the technologist provides.
- Press the patient event button to mark any events (seizures or other).
- Pediatric or mentally/cognitively impaired patients must be accompanied with a parent or guardian. All patients are strongly encouraged to bring an escort to help report events. Meriter does not provide "sitters" for the procedure.
- Do not chew gum!
- Do not get the equipment wet or damage it in any way.
- Relax and do activities that do not involve physical activity, such as reading, watching TV/movies, or crafts.
- Meriter will provide a VCR and TV for entertainment. Movie selection is limited.
Exam Procedure
Video monitoring is usually performed in the Neurodiagnostics Department or in a Nursing Unit room. The person having the test will have 24 electrodes glued to their head then remain in one area such as a recliner or a bed so the video camera can record all activities. The video camera will record physical activities while the EEG electrodes record brain activities. The test is simple and painless and lasts as long as the doctor deems necessary. Tests last from one day up to several days. Tests are usually ended when one or more typical patient events are recorded satisfactorily. Once an event is recorded, the technologist and/or doctor will review it then decide if there is enough data to terminate the test. In some situations, the test may be ended without an event if the doctor decides there is sufficient information. Every test is individualized based upon the patient's situation and symptoms.
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Description
The BAER test records your brain reactions to auditory stimuli. When your brain processes sound, it also produces a neuronal event that can be detected, visualized and recorded with special testing equipment. The BAER test is not performed to check hearing impairment. It is performed to detect problems in the auditory pathways of the brain including the brainstem. The test is painless, non-invasive and takes 45 minutes to 2 hours. Patients who are hearing impaired take longer to test than people with normal hearing.
Patient Instructions
- Arrive for the test with clean dry hair.
- It is not necessary to change your medication, sleep or eating routines.
- Test result quality is improved when you are able to relax for the test.
Exam Procedure
You are positioned on a reclining chair or bed and are asked to relax and remain still. Electrodes are placed on your scalp, along the top of your head and behind each ear. A pair of headphones are placed over your ears. You will hear clicking noises or tone bursts through the headphones, and the electrodes pick up the brains response and record it on a specialized computer. It may take several minutes to test each ear separately. At the end of your test, the technologist will clean your scalp. A neurologist will interpret the results.
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Description
Visual Evoked Potentials are tests that check the visual pathways of your brain. Visual Evoked Potentials are not to check your vision, they are to check the speed of visual signal transmission through your brain.
Patient Instructions
- Get plenty of sleep/rest before arriving to the test. Obtaining good test results depend on your level of alertness.
- Have clean, dry hair.
- Bring your glasses as the test is usually performed with your glasses on.
- Eat normal meals and take your medications unless your doctor tells you not to.
Exam Procedure
The test is performed in a chair. You will have about 6 electrodes applied to various parts of your head. The electrodes are attached using a mild paste that easily washes off with warm water and soap/shampoo. The procedure will take approximately one hour.
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Description
SSEP tests are used to record nervous system reaction time to small electrical impulses. A small electrical tapping pulse is applied to the median nerve at the wrist and/or to the tibial nerve at the ankle. The pulsation creates a reaction in the nerve that is carried up the arm/leg, through the spinal cord and into the brain. Recording electrodes applied to different points on the skin and scalp record the reaction signal as it passes through the nervous system. The result is a waveform pattern that can be measured. The measurements of the waveform are used to help your doctor diagnose certain nervous system conditions. The test takes approximately 45 minutes per nerve.
Patient Instructions
- Arrive for the test with clean, dry hair.
- Wear loose fitting clothing so the technologist can apply electrodes to your arms and legs.
- It is not necessary to change your medication, sleep or eating routines.
- Test result quality is improved when you are able to relax for the test.
Exam Procedure
Recording electrodes are applied with paste to your scalp, neck, back, arms and legs. You will be positioned on a reclining chair or bed and asked to relax and remain still. During the test you will feel a tapping/tingling/pressure type of sensation where the nerve stimulator is positioned. The recording electrodes pick up nerve, spine and brain responses. It takes a few minutes to test each nerve separately. A specialized computer will display and print the results which are interpreted by a neurologist. At the end of your test, the technologist will clean off the electrodes.
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Description
Intraoperative Monitoring is the process of monitoring the function of brain, spinal cord, and/or individual nerves during surgery. Monitoring is performed to verify integrity of neuronal structures that could be at risk during surgery. Types of surgeries routinely monitored at Meriter include:
- Carotid Endarterectomies
- Spinal Fusion with Instrumentation (PSF, TLIF)
- Cervical Corpectomies
- Aneurism Clipping
- Brain Tumor Removal
- AVM Repair
- Any other surgery that the surgeon feels would benefit from monitoring
Patient Instructions
Patients follow the pre-op instructions given by the surgeon.
Exam Procedure
In most cases, the monitoring technologist goes to the patients room prior to surgery to apply monitoring electrodes. The technologist may apply recording electrodes in the holding area and in rare cases in the OR just prior to surgery. During surgery the technologist obtains pre and post anesthetic baseline readings and compares them to ongoing data obtained during the critical portions of surgery. Feedback to and from the surgeon regarding the test data is also ongoing. Types of testing modalities include:
- EEG
- SSEP
- BAER
- Spontaneous EMG
- Triggered EMG
- Visual EP
- Transcranial electric motor evoked potentials
- Other
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12/4/2004
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