Webster's New World Medical Dictionary

stroke prevention
Methods of preventing the
occurrence of a cerebrovascular accident. If a per-
son has a transient ischemic attack (TIA), a neuro-
logical event with the symptoms of a stroke, the
symptoms go away within a short period of time.
TIAs are often caused by narrowing or ulceration of
the carotid arteries, however, and if that is not
treated, there is a high risk of major stroke in the
future. A person who suspects that he or she has
had a TIA should seek medical attention right away.
An operation called a carotid endarterectomy can
clean out the carotid artery and restore normal
blood flow through the artery, markedly reducing
the incidence of a subsequent stroke. In other
cases, when a person has a narrowed carotid artery
but no symptoms, the risk of stroke can be reduced
with medications such as aspirin and ticlopidine
(brand name: Ticlid). These medications act by par-
tially blocking the blood-clotting function of the
platelets in the patient’s blood. Controlling other
factors that contribute to strokes, such as high
blood pressure and diabetes, is also important for
stroke prevention.
stroke volume
The amount of blood pumped by
the left ventricle of the heart in one contraction. The
stroke volume is not all the blood contained in
the left ventricle; normally, only about two-thirds
of the blood in the ventricle is expelled with each
beat. Together with the heart rate, the stroke volume
determines the output of blood by the heart per
minute (cardiac output).
study 1
A procedure or an examination.
2
A
research project.
Sturge-Weber syndrome
A congenital, but not
inherited, disorder that affects the skin, the neuro-
logical system, and sometimes the eyes and internal
organs. The main sign of Sturge-Weber syndrome is
a port-wine stain birthmark. Neurological symp-
toms of Sturge-Weber syndrome may include
seizures and developmental delay. See also 
port-
wine stain.
stuttering
A speech disorder characterized by
repetition of the sound of a word. Stuttering can
usually be eliminated or significantly modified with
speech therapy. See also 
cluttering; communica-
tion disorder; speech disorder.