Deep Brain Stimulation for Improved Generalized Dystonia
An uncommon movement disorder in children, dystonia is primarily treated with medication. When this treatment plan fails, deep brain stimulation (DBS) has proven an effective approach.
“The majority of patients we see don’t consider DBS because it’s a last resource treatment and, generally, medications are effective in managing dystonia,” says Migvis Monduy, MD, pediatric neurologist and Medical Director of the Neuromuscular and Movement Disorders Programs at Nicklaus Children's Hospital. “However, for refractory patients with severe generalized dystonia, DBS is a wonderful option not commonly offered, and we’re glad to provide it locally here in Florida.”
Reaching Out for DBS
Though other hospitals offer DBS for pediatric dystonia patients, few offer the comprehensive multidisciplinary care necessary for optimal immediate and long-term results. Through Nicklaus Children’s Movement Disorders Program, children with dystonia receive comprehensive care from our multidisciplinary team that includes the following specialties:
Following comprehensive evaluation, the team determines the presence and extent of dystonia. Most patients then begin medication therapy. In those rare cases when medication is unsuccessful, the team considers DBS. As DBS is most effective in a subset of pediatric patients, determining candidacy is necessarily time consuming and elaborate.
“Evaluating the patient is an extensive process that requires going through a period of medication management before even considering surgical options,” Dr. Monduy says. “Based on the cause of dystonia, we know that particular genetic mutations respond better to DBS.”
Children presenting genetic mutations best served by DBS, who have normal MRI results, can gain candidacy. For patients without genetic mutations, who have dystonia associated with structural or anatomical lesions, MRI review is important to determine whether the child may be a DBS candidate. This evaluation serves as confirmation that the targeted area for stimulation is intact and uninjured.
Regaining Form and Function
At the age of eight, Tamryn experienced his first dystonia symptom when his foot turned in. Eight months later, his whole body contorted, stripping him of his ability to walk. A year later, Dr. Monduy became the fifth neurologist to care for Tamryn. By this time, Tamryn’s back arched constantly, and he could not sit comfortably. He developed pain and dystonic storming, with his uncontrolled spasms requiring multiple hospitalizations.
Genetic testing revealed that Tamryn had the genetic mutation that responds well to DBS. When he was transferred to the PICU for management of status dystonicus, the care team elected to operate urgently given the severity of Tamryn’s dystonia.
On April 4, 2024, Toba Niazi, MD, Co-Medical Director of the Brain Institute at Nicklaus Children’s Hospital, implanted the DBS device. Following implantation, Dr. Monduy took an aggressive approach to titration, accelerating the effects of the procedure. While improvement for mutation-involved dystonia usually requires between six and nine months, Dr. Monduy’s more aggressive approach allowed Tamryn to walk again less than five months after the implantation. Dr. Monduy anticipates the remaining twist in Tamryn’s body to correct partially or entirely within the coming months and years.
Primary Hope for Secondary Dystonia
Along with improving quality of life for children whose dystonia is brought on via genetic mutation, DBS also helps children whose dystonia is caused by an underlying condition, such as cerebral palsy (CP). Dr. Monduy states that while the outcomes for children with CP seem muted compared to those with certain genetic mutations, the improvement is meaningful for the child and can have a profound effect on quality of life.
“The goal is to realize 30% to 50% improvement for children with CP,” Dr. Monduy says. “That improvement is significant when it allows them to reduce their intake of medications that can be sedating and affect cognitive abilities.”
Such improvement is difficult to measure with clinic- or hospital-based testing. To measure, team members engage the patients’ family members to determine a baseline of activities—what the patient can and cannot do and the level of difficulty performing those tasks prior to the procedure. Following surgery, the team gathers data a second time, including video recordings, to compare and measure improvement.
Increased Efficacy With Early Intervention
Useful as DBS may be for the correct pediatric patient, its effect is most potent when prescribed in a timely manner.
“If you wait too long, after the child has remained in a constricted position for a long period, you will have orthopedic issues to address, and the overall response won’t be as positive,” Dr. Monduy says. “You may eliminate dystonia with the procedure, but the patient’s range of motion may not improve.”
Additional surgeries can help to correct deformities, but Dr. Monduy insists the best solution is to offer DBS at the earliest possible stage. Along with receiving DBS early, the patient can maximize the benefits of DBS through fully following medical orders.
Rehabilitative therapy helps retrain the body to move correctly following weeks, months or years in contorted positions. Weakened, inactive muscles must be strengthened and retrained to perform their jobs properly. Social constraints must be addressed to ensure families have both realistic expectations going into the procedure and commitment to ongoing maintenance. Without such commitment, the patient may be precluded from receiving DBS.
The team at Nicklaus Children’s is proud to offer DBS for those who meet inclusion criteria and show promise to fulfill their obligations after the procedure.
“We have all the services and specialists needed to provide excellent care for children with dystonia,” Dr. Monduy says. “Our multidisciplinary team evaluates the child’s need, ensures a safe plan and strong support system are in place, and offers support to ensure families have the help and equipment they need along their journey.”
To refer a patient or learn more about Nicklaus Children’s Movement Disorders Program, email our physician liaison.