Surgery for refractory infantile spasms

Hiscott, Rebecca

ARTICLE IN BRIEF

Researchers reported at the Child Neurology Society annual meeting that the best surgical outcomes for children with refractory epileptic spasms occurred in those who had lesional abnormalities on MRI with EEG concordance. But even those who had no MRI lesion but positive PET localization fared well.

The best surgical outcomes for children with refractory epileptic spasms occurred in those who had lesional abnormalities on magnetic resonance imaging (MRI) with electroencephalogram (EEG) concordance, according to a study presented at the Child Neurology Society annual meeting in National Harbor, MD.

But importantly, even those patients who had no MRI lesion but positive positron emission tomography (PET) localization fared well, study author Harry T. Chugani, a professor of pediatrics, neurology, and radiology, the Rosen Family chair in Tourette syndrome, and director of pediatric neurology at Children's Hospital of Michigan, told Neurology Today. Those who received surgery within three years of seizure onset also had largely positive outcomes, he noted.

Infantile spasms are a type of epileptic seizure seen in West syndrome, which occurs in infancy and early childhood. These spasms — in which children bend forward with a stiffening of the arms and legs, or arch their backs and extend the arms and legs — tend to occur upon awakening or after feeding, often in clusters of up to 100 seizures at a time, with as many as dozens of clusters and hundreds of spasms per day.

 

STUDY METHODOLOGY, RESULTS

 

For the study, which has been accepted for publication in Epilepsia, Dr. Chugani and his colleagues reviewed data for 65 children with refractory infantile spasms who underwent surgery between 1993 and 2014 at the Children's Hospital of Michigan, excluding palliative cases. The mean age at surgery was about five years, and patient outcomes were assessed after surgery, on average, at about 43 months. The patients took an average of 4.2 anticonvulsant medications prior to surgery, which declined to a little over one after surgery (p<0.0001).

Among the findings, 46 of the 65 patients (71 percent) achieved complete seizure freedom with no auras — considered an International League Against Epilepsy (ILAE) class 1 outcome — at follow-up, and 22 were able to go off medication. All patients (20 out of 20) who underwent total hemispherectomy achieved ILAE class 1 outcomes, as did 10 of 17 subtotal hemispherectomy cases, seven of 13 multilobar resection cases, six of seven lobectomy cases, and three of six tuberectomy cases. Neither of the two lobectomy/tuberectomy surgery cases achieved class 1 outcomes.

Of the 47 patients with lesional MRI, 79 percent had class 1 outcomes, compared with 50 percent of patients with normal MRI, the researchers reported. PET scans were abnormal in almost all patients (61 of 63); there was lateralization/localization in 92 percent, and this helped in surgical decision-making and guiding subdural grid placements, particularly in those with non-lesional MRI. And 30 of 34 patients (88 percent) who underwent surgery within three years of seizure onset achieved seizure freedom, Dr. Chugani and colleagues reported.

Many patients with infantile spasms who are MRI-negative don't get a PET scan, said Dr. Chugani, who will be moving to the DuPont Hospital for Children in Wilmington, DE, in December. But a PET scan may identify a focus that suggests a patient is a viable candidate for surgery. “Don't write these MRI-negative patients off, because one out of two of them will be seizure-free with surgery,” he said.

Ultimately, there are two take-home messages from this study, Dr. Chugani said: “Do surgery early, within three years of seizure onset, and don't write off MRI-negative cases.”

EXPERTS COMMENT

Douglas R. Nordli Jr., MD, division head of the Epilepsy Center at the Lurie Children's Hospital of Chicago and the Langdon chair of pediatric epilepsy and a professor of pediatrics and neurology at Northwestern University Feinberg School of Medicine, said the study is “a nice continuation of the pioneering work” by Dr. Chugani and his colleagues, “demonstrating in a fairly long follow-up that good results can be achieved” with surgery in patients with infantile spasms.

“These data point out that even in the group that's MRI-negative, if the PET shows an area of hypometabolism or a focus, the patients can do very well,” Dr. Nordli said. “It is a very nice publication from a seasoned researcher and clinician who has always been at the forefront of PET development.”

Phillip L. Pearl, MD, director of epilepsy and clinical neurophysiology at Boston Children's Hospital and the William G. Lennox chair and professor of neurology at Harvard Medical School, agreed. “This is an important series over a 20 year span demonstrating the value of epilepsy surgery for infantile spasms, including in MRI-negative patients,” he said.

It would be interesting to see data on how children who received surgery within three years of seizure onset fared in the long run in terms of seizure frequency and developmental outcomes compared with those who received surgery later, he added.

“This group has shown us that surgery is a viable option for selected patients with infantile spasms, and that a more efficient or expeditious surgical decision appears to be in the best interest of the patients,” he said.

http://journals.lww.com/neurotodayonline/Fulltext/2015/11050/Which_Children_with_Refractory_Epileptic_Spasms.3.aspx