MRI-Guided Laser Ablation System Allows Less Invasive Epilepsy Surgery
Pediatric neurosurgeons at Cincinnati Children's recently began offering less invasive surgery for patients with intractable epilepsy using the Visualase® magnetic resonance-guided stereotactic laser ablation system. Stereotactic procedures for minimally invasive treatment of epilepsy may ablate seizure foci with less damage to normal surrounding tissue than resective surgery.
The first surgical case using this technology at Cincinnati Children's was on April 21. The nine-year-old patient had previously undergone a craniotomy to resect the seizure foci in 2013, but was still experiencing seizures. MR imaging revealed residual abnormal tissue in the hippocampus that could have been causing the seizures. Since undergoing the ablation procedure, the patient has not experienced any seizures. The treatment team will monitor him closely for a year before being able to say with certainty whether he is seizure free.
“In the past we would have had to re-open the craniotomy to remove this tissue, even though the area to be resected was relatively small," says Francesco Mangano, DO, chief of pediatric neurosurgery at Cincinnati Children's.
The technology allows neurosurgeons to guide a laser applicator to the target area through a small incision – while the patient is in a magnetic resonance scanner. Laser light heats and destroys the target area, with minimal risk of potential damage to surrounding, healthy tissue. The technology uses functional MRI, stereotactic navigation and intraoperative neuromonitoring, so that the surgeon can see the target lesion as it is being destroyed.
“With previous technologies, such as radiation therapy, the tissue would not die right away," says Dr. Mangano. “You wouldn't know whether you were successful, and you wouldn't know for several months. With this system, the tip of the laser destroys tissue in the hippocampus, and you can see that in real time. You take out the catheter, close the incision, and you're essentially done."
Visualase is the latest imaging technology used to extend the capabilities of neurosurgeons at Cincinnati Children's. “Our goal is to decrease the invasiveness of surgery and decrease complications while getting excellent, seizure-free outcomes," says Hansel Greiner, MD, a neurologist and co-director of the epilepsy surgery program at Cincinnati Children's. “This requires a major investment in equipment and highly-trained staff to give Dr. Mangano the best information about where the seizure-causing tissue is. The better our information, the more likely it will be that he can perform less invasive surgery."
Dr. Mangano is quick to acknowledge the contributions of every member of the epilepsy surgery program's multidisciplinary team. “We now have a team of pediatric specialists in epilepsy, neuropsychology, neuroradiology, neurosurgery and pathology," he says. “This has resulted in little surgical morbidity, no mortality and excellent outcomes from seizures. As many as 60 percent of patients can be seizure free within a year. This is a terrific outcome, considering those patients were deemed intractable by their neurologists before they came here to the Comprehensive Epilepsy Center, and may have had epilepsy for many years prior."
