Neurosurgeons affiliated with the Memorial Hermann Mischer Neuroscience Institute at the Texas Medical Center have pioneered several innovative surgical approaches for epilepsy, the most recent of which is MR-guided laser interstitial thermal therapy (MRgLITT) using the Visualase™ system. Known as laser ablation, this innovative technology offers physicians and patients a precise, minimally invasive surgical intervention for the treatment of well-delineated focal epilepsies.

About the Laser Ablation Procedure

Surgical planning begins after the epileptogenic focus has been precisely located on a high-resolution MRI scan. A 4-millimeter incision and 3.2-millimeter drill hole are then made in very precise fashion using either a stereotactic head frame or a stereotactic robot. This drill hole is used for the insertion of the laser applicator. After the applicator has been positioned in the target area, the patient is placed in an MRI scanner and thermal destruction of tissue by elevation to lethal temperatures is carried out while obtaining MRI scans.During the procedure, the neurosurgeon uses the system’s temperature maps and real-time damage models to precisely ablate the target and minimize the risk of potential damage to surrounding healthy tissue.

Temperature limits may be set to protect critical brain structures.

Laser Ablation Treatment Time

The entire procedure typically lasts a few hours, though the actual ablation takes only a few minutes. The real-time MR imaging allows the surgeon to confirm the surgical results immediately. Most patients are hospitalized for just 24 hours and often go home the next day after the procedure.

Benefits of Laser Ablation

  • Minimally invasive approach eliminates the need for craniotomy
  • Preservation of eloquent areas of the brain, including speech, memory, vision and motor and sensory function
  • Of specific value in minimizing the impact on memory and on visual naming
  • Very small incision that is generally closed with a single stitch
  • Short patient hospital stays, usually 24 hours
  • Rapid recovery and return to daily activities and work within a week
  • Minimal pain and postoperative discomfort
  • Improved cosmesis (most patients have little hair shaved)

Collaboration with Referring Physicians

Mischer Neuroscience Institute engages referring physicians in the care of their patients, keeping them informed about patient progress throughout the evaluation and treatment process. After a patient’s office visit, referring physicians receive a summary that includes the initial diagnosis, pending tests and treatment options. The physicians encourage continued communication regarding patient progress as needed.

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