At Boston Children’s Hospital, we see children from newborns through adolescents with a variety of stroke conditions. These include arterial and venous strokes, ischemic and hemorrhagic strokes and strokes caused by specific underlying conditions, such as congenital heart disease, sickle cell disease, moyamoya disease and other diseases of the blood vessels. Stroke can affect all parts of the brain and spinal cord.
Most pediatric stroke is “ischemic” or “thrombotic” in nature, meaning that blood stopped flowing to an area of the brain for long enough to cause damage.
About childhood stroke
Stroke can occur at any time in a child’s life. Neonatal stroke, or stroke in newborns, occurs in as many as 1 in 1,600 to 1 in 4,000 full-term infants and even more commonly in babies born prematurely. Sometimes strokes even occur before birth. Most often, neonatal stroke is discovered shortly after birth in babies who have seizures or who are weak and unresponsive, and confirmed through neuroimaging. Once the diagnosis is made, we rapidly evaluate the infant to identify any underlying disorder that could predispose her to a second stroke if untreated. Once we find a cause for stroke, we start therapies immediately to help the child develop as normally as possible.
After the newborn period (the first 28 days of life), stroke is much more rare but can be fatal, making early recognition and treatment vitally important. Childhood stroke can be associated with congenital heart disease, abnormalities in blood vessels, disorders that increase the blood’s tendency to clot, infection or inflammation. Strokes occur more often in boys than girls and more often in African- Americans than in Caucasians.
Stroke conditions go by many medical names, so if your child has received a diagnosis that’s not listed here, it’s very likely that we treat it. The major pediatric stroke conditions we treat include:
An arterial ischemic stroke (AIS) in children is usually due to obstruction of blood flow to a region of the brain or spinal cord, preventing oxygen from being delivered. AIS can be caused by blood clots that form inside an artery in the brain or spinal cord, or by clots that pass through the heart, enter the general circulation and then lodge in an artery in the brain or spinal cord. Structural abnormalities of the cerebral arteries themselves, known as cerebral arteriopathies, can also cause AIS. One example is cerebral vasculitis, while another is moyamoya disease.
Rather than ischemia, or obstruction of blood flow, some strokes are caused primarily by bleeding, or hemorrhage, within the brain. This bleeding usually results from blood-vessel abnormalities, such as cavernous malformations, arteriovenous malformations, venous angioma and aneurysm. Clotting disorders such as hemophilia, sickle cell disease, brain tumors and congenital heart disease can also cause bleeds that lead to hemorrhagic stroke. Hemorrhagic stroke is also referred to as cerebral hemorrhage or intracranial hemorrhage.
Occasionally, children with ischemic stroke can develop hemorrhagic transformation of their initial stroke, meaning that bleeding can sometimes develop as a complication of the ischemic injury itself or the medicine used to treat it.
- Non-traumatic cerebral hemorrhage
This term refers to bleeding in the brain that does not arise from trauma, but from blood vessel abnormalities or other disorders. It can lead to hemorrhagic stroke (see above), but research indicates that about half of children with non-traumatic intracranial hemorrhage will have no lasting deficit. We provide close follow-up to ensure optimum long-term outcomes.
- Cerebral sinus thrombosis
Cerebral sinus thrombosis occurs when a blood clot forms in the brain’s venous sinuses, channels that return blood from veins in the brain to the heart. It has been increasingly diagnosed in newborns and children and can cause an ischemic stroke and injury to the brain. Previously, clinicians were reluctant to treat this condition with anticoagulation, which itself can pose some risks, but confidence has grown in using anticoagulants to prevent injury from the blood clot in selected newborns and children. Children are closely monitored by the Thrombosis and Anticoagulation Program at Boston Children’s, which collaborates closely with the Stroke Program.
- Cortical venous thrombosis
Cortical or cerebral venous thrombosis occurs when a blood clot forms in a vein within the brain. Such clots can obstruct blood flow and increase blood pressure in the brain’s venous circulation (the side of the circulation that returns blood to the heart), sometimes to the point that an ischemic stroke occurs. It is important to detect cortical venous thrombosis early and to consider treatment with anticoagulation.
- Transient ischemic attack
Transient ischemic attacks (TIAs) are temporary deficits in neurologic function caused by a brief interruption of blood flow to part of the brain. In children, TIA symptoms may include weakness or numbness on one side of the body, difficulty speaking or a “room spinning” sensation. While these symptoms are short-lived and resolve on their own, TIAs can be accompanied by lasting injury to brain tissue. Our research indicates that about 10 percent of children who experience a TIA ultimately have a stroke, sometimes with little or no warning.