Cerebellar deep brain stimulation shows promise for addressing dystonic cerebral palsy

Key takeaways:

• Dystonic cerebral palsy presents several challenges to successful symptom management.
• A pilot study of cerebellar deep brain stimulation has yielded positive preliminary results.

ORLANDO, Fla. — Managing dystonic cerebral palsy in younger populations presents unique challenges, which may be addressed with direct cerebellar implantation of a deep brain stimulation device, according to a presenter.

“While the majority of patients with cerebral palsy have muscle spasticity, up to 20% have abnormal involuntary movements,” Marta San Luciano, MD, neurologist in the Movement Disorders and Neuromodulation Center at the University of California, San Francisco, said at the American Neurological Association annual meeting. “Comorbidities are common, including intellectual disabilities, epilepsy and most patients develop orthopedic complications.”

For individuals with this dystonic cerebral palsy, San Luciano continued, symptom management is challenging due to the unpredictability of mixed movement, risk of worsening dystonia, lack of efficacious medication and little empiric evidence from clinical trials; however, these issues may be solved via electronic means via deep brain stimulation (DBS).

In theory, implantation in the cerebellum may provide necessary relief from dystonia, as lesions found within the cerebellum are an indicator of movement-related symptoms, San Luciano said.

Further, she added, individuals with dystonia may present with lesions in the cerebellum — although those found in the pallidus and thalamus are more common — alongside subtle dysfunction in that area, whose abnormalities can be found via functional imaging. Therefore, targeting these lesions may lead to better symptom management. Conversely, DBS showed no improvement in spasticity or choreoathetosis and there is always a chance that the hardware necessary for implantation may not work properly.

San Luciano referenced a pilot study, for which she is a co-author, that investigated DBS in cerebral palsy. The study included three individuals between aged 14 to 22 years with severe dystonia along with pallidal or thalamic lesions confirmed by MRI. All were implanted with a Medtronic Percept DBS device with leads on the dentate nucleus, set to 145 Hertz.

Preliminary study results showed improvements in subjective criteria such as greater head and hand control, less limb tightness, improved clarity and fluency in speech. Additionally, one participant was ambulatory with brain stimulation switched on and another was able to control a motorized wheelchair. All three participants registered objective improvement as measured by the Burke Fahn Marsden Dystonia Rating Scale, ranging from 19% to 40%.

San Luciano and colleagues are also currently investigating cerebellar DBS in an ongoing NIH/NINDS BRAIN initiative-funded study which aims to test chronic dentate stimulation to quell severe dystonia in cerebral palsy. The researchers’ goal is to assess neurostimulation in the cerebellum in those aged 7 to 25 with dyskinesia. The first enrollee was implanted with a DBS device in late August.

“Not much is known of human cerebellar neurophysiology,” San Luciano said. “These patients open up the possibility of study of dystonic recordings over time.”

Reference:

Cajigas I, et al. J Neurosurg. 2023;doi:10.3171/2023.1.JNS222289.