Decreased blood supply to the brain can be caused by carotid artery disease, and result in a transient ischemic attack (TIA) or mini-stroke. One of the symptoms of TIA is difficulty with speech.
Difficulty with speech can be the result of problems with the brain or nerves that control the facial muscles, larynx, and vocal cords necessary for speech. Likewise, muscular diseases and conditions that affect the jaws, teeth, and mouth can impair speech.
What is carotid artery disease?
The carotid arteries provide blood supply to the head. There are two common
carotid arteries, located on each side of the neck, that divide into the
internal and external carotid arteries. The external carotid artery provides
blood supply to the scalp, face, and neck while the internal carotid artery
supplies blood to the brain.
Narrowing of the internal carotid artery may decrease blood supply to half of
the brain that it supplies. This narrowing called atherosclerosis (atheroma =
lump of plaque + sclerosis = hardening) occurs because of the accumulation of
plaque on the inside of the artery wall. Plaque begins as a soft, waxy
collection of cholesterol and triglycerides but over time begins to harden and
calcify. Often it occurs where increased blood pressure and blood turbulence
irritates the inner lining of the artery and this often occurs where the
internal and external carotid arteries split (bifurcation).
As the carotid artery begins to further narrow, the pressure within the
artery continues to increase. This may cause the plaque to rupture, causing
blood clots to form. A large clot may completely block (occlude) the artery or
smaller clots and bits of plaque may travel into smaller arteries within the
brain and cause disruption of blood supply to parts of brain tissue.
It is only when a stroke or transient ischemic attack occurs, or a bruit
(blowing or whistling sound) is found on physical examination by your doctor,
that the diagnosis of carotid artery disease is usually made. Otherwise, the
narrowing carotid artery does not cause symptoms.
What are the causes of carotid artery disease?
Carotid artery disease occurs because of damage to the inner lining of the
artery. This is a gradual process that is associated with smoking, high blood
pressure, high cholesterol levels, and poorly controlled diabetes. These all may
cause minor damage to the inner walls of an artery, and during the healing
process, inflammation may occur and plaque may begin to form.
Over time, the area of plaque may grow and narrow the lumen of the artery,
the channel where blood flows. It becomes a vicious circle as the narrower lumen
increases pressure within the artery and blood turbulence, which leads to more
arterial wall damage and more plaque formation.
Picture of Carotid Artery Disease
Medically Reviewed by a Doctor on 11/5/2015