Cerebral Revascularization in the Very Young
When children under age three develop sickle cell-related Moyamoya disease, arteriopathy can progress quickly. Therapies such as blood transfusion and hydroxyurea have reduced the incidence, but it may be as high as 30 to 44 percent.
While it may be tempting to wait until the child is older to perform revascularization, the benefits of an earlier surgical intervention often outweigh the risks, says Sudhakar Vadivelu, DO, an endovascular pediatric neurosurgeon at Cincinnati Children’s Hospital Medical Center. “Waiting puts patients at increased risk for stroke, and once there has been a completed stroke, we cannot do a revascularization,” says Vadivelu, a specialized pediatric neurosurgeon who is fellowship trained in both open and endovascular approaches to cerebrovascular disease for children.
Revascularization in these patients can be challenging technically due to their small blood vessels and anesthetic risks at a very young age, but a recent case at Cincinnati Children’s shows the benefit of early intervention. The patient, Andrea Williams, had been diagnosed with sickle cell disease as a newborn, and had a right-sided parietal stroke at 20 months in October 2015. The care team in her hometown of Louisville provided a preliminary diagnosis of sickle cell-related Moyamoya. A neurologist told Andrea’s parents that if the diagnosis was confirmed, he recommended waiting until she turned five years old to perform revascularization.
Following the stroke, Andrea’s left side was paralyzed, making it impossible for her to walk, sit up, speak or drink from a cup. Anxious to avoid another debilitating stroke, Andrea’s parents brought her to the Cerebrovascular Disease Center at Cincinnati Children’s for a second opinion. The center is unusual in that all of its providers are pediatric specialists, coming from neurosurgery, interventional radiology, neurology, medical oncology, neurospsychology, physical medicine and rehabilitation, and stroke care, among other clinical areas. In addition to treating patients with Moyamoya, the Cerebrovascular Disease Center at Cincinnati Children’s provides expert surgical care for patients with conditions that involve blood vessel lesions, such as aneurysms, arteriovenous malformations, stroke and vascular tumors.
“We are able to treat very young patients with Moyamoya disease because we offer the option of indirect revascularization,” says Vadivelu. “This procedure involves transposing the vessel away from its native place and suturing it side by side a recipient vessel. Children tolerate this surgery very well. Within a few months, magnetic resonance imaging shows that donor vessels have grown and new blood vessels have formed and are providing a good supply of blood to the brain.”
After extensive tests, including imaging studies showing that Andrea had bilateral internal carotid stenosis, Vadivelu performed two separate indirect revascularization procedures six weeks apart. Before and after the surgeries, Vadivelu collaborated with the hematology team at Cincinnati Children’s, particularly Charles Quinn, MD, MS, medical director of the hospital’s Pediatric Sickle Cell Program, to ensure that Andrea’s complex medical needs were met.
Andrea recovered quickly from both surgeries, and subsequent MR imaging confirmed that the revascularizations were successful in restoring blood flow to the brain. She returns to the Cerebrovascular Disease Center periodically for follow-up care, and continues to receive monthly apheresis therapy. Despite her multiple health challenges, Andrea has almost caught up with her peers developmentally in terms of her motor and speech skills. She is in a preschool program, and participates in gymnastics, dancing and swimming. Although still very young, she already has a career path in mind: becoming a doctor.
Vadivelu expects Andrea to need lifelong care to manage her stroke risk, but says it is unlikely that an additional revascularization will be needed. “Long-term studies suggest that when young children with sickle cell disease-related Moyamoya do not undergo revascularization, their risk of recurrent transient ischemic attack or stroke is 50 to 66 percent,” he says. “For those who have cerebral revascularization, the risk is lowered to 2.2 to 5.3 percent.”
Cincinnati Children's has created a two-minute, animated patient information video about Moyamoya disease, which is narrated by Dr. Vadivelu and describes the disease's progression, diagnosis and treatment.
For more information about the Cerebrovascular Disease Center or to refer a patient, contact cerebrovascular@cchmc.org.