fMRI benefits in noninvasive evaluation of epilepsy patients

Functional magnetic resonance imaging (fMRI) of the brain lowers the need for invasive testing of seizure disorder patients, according to a study published in the July issue of Radiology.

 "fMRI gives the surgical team an important roadmap of the brain function without contrast injections or invasive tests," said the study's lead author, L. Santiago Medina, MD, MPH, co-director of neuroradiology and director of the Health Outcomes, Policy and Economics Center at Miami Children's Hospital. "This imaging technology is a powerful tool that improves surgical decision making in patients being considered for seizure surgery."

 For the study, Medina looked at the effect of fMRI results on the diagnostic work-up and treatment planning of 60 consecutive seizure disorder patients, including 33 male and 27 female patients.

Based on fMRI results, five patients in the study avoided a two-stage surgery with extra-operative direct electrical stimulation mapping and instead received a one-stage resection surgery. The extent of surgical resection was altered in another four patients, because fMRI images identified critical areas of the brain close to the seizure focus, according to the study.

Other changes in patient care were as follows:

• The team altered patient and family counseling in 58 percent of patients
• Intraoperative mapping was altered in 52 percent of patients
• Overall surgical plans were altered in 42 percent of patients
• 63 percent of patients were able to avoid further studies     

Of the study's 60 patients, 32 were not candidates for surgery or refused surgical treatment. Of the 28 patients who proceeded with surgery, 17 were seizure-free following the resection, and eight had a 50 percent to 90 percent reduction in seizures. Three of the surgical patients experienced less than a 50 percent reduction in seizures at six-month follow-up, the study said.