WHAT IS MEG?: MEG Measurement

MEG Study Step-By-Step

STEP 1: The patient arrives and gives an informed consent for the MEG exam. Potential sources of magnetic artifacts, such as a steel belt buckle, are then identified and removed or demagnitized.

Step 1.

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STEP 2: Marker coils are place on the patient's head to record the position of the head during the exam. Next, the nasion is marked for identification during the digitization process. This information is later used to register the MEG source localizations with the patient's MRI.

Step 2.

STEP 3: EEG electrodes are also attached for epilepsy studies or to monitor heart rate, eye blinks or EMG.

Step 3.

STEP 4: The patient then enters the Magnetically Shielded Room (MSR) and the location of the coils (and EEG electrodes if desired) are digitized. This process defines the head frame of reference. Then, the shape of the patient's head is digitized for the source localization process.

Step 4.

STEP 5: Patient is then placed in the MEG system and made to be comfortable. If an epilepsy study is being conducted, the patient needs just to relax and lie still. If a somatosensory study is being conducted, pneumatic finger tappers are placed on the hand and are activated during the scan.

Step 5.

STEP 6: Once the patient is in the system, the staff can monitor the patient via an intercom system and video monitor. During this completely painless and non-invasive exam the staff can view the real time MEG data along with the EEG data. A somatosensory exam takes about 1 1/2 hours to complete and an epilepsy exam about 2-3 hours. Once the study is completed, all of the coils are removed and the patient can leave without restrictions.

Step 6.

STEP 7: Once the patient leaves, the data from the study is reviewed and analyzed. MEG source localizations are then overlaid onto the patient's MRI and a report is generated for the referring physician.

Step 7.

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