Multiple Subpial Transection

Multiple subpial transection (MST) is a technique used to disconnect areas of the brain where seizure activity occurs. The goal of the surgery is to stop the spread of irregular electrical activity that causes seizures. The procedure may be recommended when the area of epileptic activity in the brain is not able to be resected and does not respond to medication. The surgery aims to destroy fibers that transfer the epileptic electrical activity while protecting other fibers that provide critical function such as language and motor skills.


Is my child a candidate?

  • Your child may be a candidate for MST if they are experiencing partial seizures that do not respond to medication and are originating in an area of the brain that is not resectable due to the location of the lesion. For example, if the area of epileptic activity in the brain also controls critical language and motor functions, the tissue may not be able to be resected and MST may be explored as a treatment option.

What testing is needed before surgery?

  • Before surgery, the exact location of the brain where the seizures originate from will need to be identified. This may involve:
    • MRI: An MRI uses large magnets, radio waves and a computer to make images of the inside of the body.
    • CT scan: This test uses a series of X-rays and a computer to create images of the inside of the body. A CT scan shows more detail than a regular X-ray.
    • EEG (outpatient): This test records the brain's electrical activity through sticky pads (electrodes) attached to the scalp.
    • EEG (inpatient): Some patients may require a longer EEG to record electrical activity in which case a stay in the epilepsy monitoring unit will be required.
    • MEG scan: MEG, or magnetoencephalography, is a noninvasive test used to localize seizures and abnormal activity within the brain using magnetic sensors. MEG can also be used to localize areas of the brain that control motor, sensory and language.

How is the surgery performed?

  • Your child will be placed under general anesthesia in a pre-operation room. Then they will be taken into the operating room and a small section of hair will be shaved from their head. Surgeons will then make an incision and perform a craniotomy, where a small portion of the skull is removed. Next the surgeons will access the cerebral cortex and make multiple small incisions on the surface of the brain. These incisions will interrupt the abnormal electrical activity, preventing the ability for it to spread and cause seizures. After, the operating team will close the incision and your child will be admitted to the pediatric intensive care unit (PICU). The patient will typically spend one night in the PICU and two to three nights in a regular hospital room before returning home.

What are the results of the surgery?

  • Complications can happen during any surgery and there is no cure for epilepsy. MST surgery is a relatively new technique that has been shown effective and safe for children with localized epilepsy. Some children may experience a temporary loss of language or motor skill, but should fully recover pre-operative function a few weeks after surgery.
To learn more about the Epilepsy Center at Texas Children’s Hospital and to inquire about admissions and patient candidates, please contact 832-822-0959.