Texas Children’s is the fourth pediatric hospital in Texas to offer magnetoencephalography (MEG), a non-invasive brain imaging technology that assists neurosurgeons in developing more precise surgical plans for patients with epilepsy and other seizure disorders, ultimately enhancing their long-term outcomes.
The MEG scanner records very tiny magnetic fields produced by electrical activity in the brain to identify the sources of normal and abnormal brain function with millimeter precision. Unlike X-ray and CT scans, MEG does not emit radiation. Instead, it works like a very sensitive microphone that records magnetic fields emitted by brain cells instead of sound.
“MEG is an invaluable tool in evaluating epilepsy patients for potentially curative brain surgery,” said Texas Children’s neurologist Dr. Michael Quach. “Prior to MEG, the only technology capable of localizing brain activity with such high temporal and spatial resolution was intracranial EEG monitoring, which requires exposing the surface of the brain with surgery in order to implant EEG electrodes. With MEG technology, we can achieve similar localization without the need for open brain surgery.”
When patients come in for a MEG scan, the MEG technician places electrodes onto the patient’s scalp before positioning the patient’s head into the scanner where the machine collects information from 306 sensors simultaneously every millisecond. The MEG images are superimposed on the MRI to correlate where the magnetic activities of brain function occur in relation to the patient’s brain structures.
When MEG and MRI are analyzed together, physicians can identify the sensory regions of the brain – like speech, touch, vision and motor function – and can localize the sources of seizures and other abnormal brain activity. With this combined information, surgical procedures can be planned more precisely to remove abnormal brain tissue while minimizing damage to parts of the brain that function normally.
“One of the great things about MEG is it gives pediatric patients a chance to qualify for epileptic surgery,” said MEG technician Michael LaRose. “With this increased data, our neurologists and neurosurgeons have a better chance of coming up with a surgical plan that may help these children with seizures.”
The MEG procedure usually lasts about an hour and a half but the amount of time it takes to complete the scan varies for each patient. Since the MEG lab opened last November, Texas Children’s has performed 25 MEG procedures.
Since very few hospitals in Houston are equipped with this advanced imaging technology, Texas Children’s also offers this service to Baylor College of Medicine physicians who treat adult patients.