Anatomy of the brain
The central nervous system (CNS) consists of the brain and spinal cord. The
brain is an important organ that controls thought, memory, emotion, touch, motor
skills, vision, respirations, temperature, hunger, and every process that
regulates our body.
- Cerebrum (supratentorial, or front of brain), composed of the right and
left hemispheres. Functions of the cerebrum include: initiation of movement,
coordination of movement, temperature, touch, vision, hearing, judgment,
reasoning, problem solving, emotions, and learning.
- Brainstem (midline, or middle of brain), includes the midbrain, the pons,
and the medulla. Functions of this area include: movement of the eyes and
mouth, relaying sensory messages (i.e., hot, pain, loud), hunger,
respirations, consciousness, cardiac function, body temperature, involuntary
muscle movements, sneezing, coughing, vomiting, and swallowing.
- Cerebellum (infratentorial, or back of brain), located at the back of the
head. Its function is to coordinate voluntary muscle movements and to maintain
posture, balance, and equilibrium.
How is a brain tumor diagnosed?
In addition to a complete medical history and physical examination of your
child, diagnostic procedures for a brain tumor may include:
- Neurological exam. Your child's physician tests reflexes, muscle strength,
eye and mouth movement, coordination, and alertness.
- Computed tomography scan (also called a CT or CAT scan), a diagnostic
imaging procedure that uses a combination of x-rays and computer technology to
produce cross-sectional images (often called slices), both horizontally and
vertically, of the body. A CT scan shows detailed images of any part of the
body, including the bones, muscles, fat, and organs. CT scans are more
detailed than general x-rays.
- Magnetic resonance imaging (MRI), a diagnostic
procedure that uses a combination of large magnets, radiofrequencies, and a
computer to produce detailed images of organs and structures within the
body. Spectroscopy is a technique sometimes used to evaluate an area for
possible tumor. a functional MRI can assist the doctors in identifying the
location of a tumor in relation to important areas such
as the speech and motor areas of the brain.
- X-ray, a diagnostic test which uses invisible electromagnetic energy beams
to produce images of internal tissues, bones, and organs onto film.
- Bone scan. Pictures or x-rays are taken of the bone after a dye has been
injected that is absorbed by bone tissue. These are used to detect tumors and
bone abnormalities.
- Angiogram. A dye is used to visualize all the blood
vessels in the brain in order to detect certain types of tumors.
- Lumbar puncture/spinal tap. A special needle is placed into the lower
back, into the spinal canal. This is the area around the spinal cord. A small
amount of cerebral spinal fluid (CSF) can be removed and sent for testing. CSF
is the fluid which bathes the brain and spinal cord.
Diagnosis of a brain tumor depends mostly on the types of cells in which the
tumor begins and the tumor location.