Deep Brain Stimulation Is Beneficial for Patients With Dystonic Cerebral Palsy

Younger patients with dystonic cerebral palsy improve six to 12 months after undergoing deep brain stimulation.

SEATTLE—Young patients with dystonic cerebral palsy may benefit from deep brain stimulation (DBS), according to results of an ongoing study presented at the 61st Annual Meeting of the American Academy of Neurology. All enrolled patients improved on at least one global rating scale following treatment with DBS.

“We undertook this investigation since there was no other viable option for treating these patients at this time,” lead investigator Warren Marks, MD, told Neurology Reviews. “There is increasing recognition that many children with spastic cerebral palsy have a significant component of dystonia. These children often respond inadequately to traditional interventions, including intrathecal baclofen,” he explained. “With the recognition that many forms of progressive dystonias respond to DBS, it seemed that nonprogressive injuries and disorders like cerebral palsy would also respond and that the response would be even more likely to be sustained over time since the underlying problem is not progressive in nature.”

Dr. Marks, a neurologist at Cook Children’s Medical Center in Fort Worth, Texas, and colleagues evaluated the effectiveness of DBS for the treatment of dystonic hypertonia related to cerebral palsy. Between September 2007 and March 2009, seven patients ranging in age from 8 to 26 had bilateral globus pallidus internus electrodes implanted using a sterotactic guidance system and microelectrode recording. One patient had generators explanted due to infection and was excluded from the analysis. All participants had been refractory to other pharmacologic interventions prior to receiving DBS; five were receiving intrathecal baclofen.

Patients were evaluated at follow-up with use of several global rating scales—such as the Marsden Dystonia Rating Score, the Dystonia Movement Scale, the Barry Albright Score, and the Gross Motor Functional Classification Score—as well as serial video analysis.

At six to twelve months following implantation, all patients demonstrated improvement on at least one of the three rating scale measures, said Dr. Marks and his team. No patients developed ambulation at six-month follow-up. In addition, the researchers noted that video analysis was useful in assessing overall status.

“Younger patients with less orthopedic contracture burden have more rapid amelioration of tonal abnormalities,” the researchers said. “The presence of fixed skeletal deformities may reduce the effective gain in the affected extremity or body region. Nonetheless, older patients may still benefit from overall tonal management.”

“It appears, therefore, that intervention by whatever method, including DBS, would be most beneficial before irreversible muscle contractures are formed,” commented Dr. Marks. However, he added that “there are many factors to take into account before considering DBS as an option for treatment.

“We are continuing our evaluations of patients with cerebral palsy and other primary and secondary dystonias,” noted Dr. Marks, whose team is collaborating with other DBS centers to develop a database through which collected data can be shared.