Webster's New World Medical Dictionary

peripheral blood stem cell transplantation
See 
stem cell harvest, peripheral blood.
peripheral nervous system
The portion of the
nervous system that is outside the brain and spinal
cord. Abbreviated PNS. The nerves in the PNS con-
nect the central nervous system (CNS) to sensory
organs, such as the eye and ear, and to other organs
of the body, muscles, blood vessels, and glands. The
peripheral nerves include the 12 cranial nerves, the
spinal nerves and roots, and the autonomic nerves.
The autonomic nerves are concerned with auto-
matic functions of the body, specifically with the reg-
ulation of the heart muscle, the tiny muscles that
line the walls of blood vessels, and glands.
peripheral neuropathy
A problem with the
functioning of the nerves outside the spinal cord.
Symptoms of peripheral neuropathy may include
numbness, weakness, burning pain (especially at
night), and loss of reflexes.
peripheral T cells
See 
T cell, peripheral.
peripheral vascular disease
Atherosclerosis of
the arteries of the extremities. Peripheral vascular
disease can lead to pain in the legs when walking
(claudication) that is relieved by resting. See also
atherosclerosis.
periphery 1
The outside or surface of a structure
or the portion outside the central region.
2
The
circumference of a circle or another geometric fig-
ure.
peristalsis
The rippling motion of muscles in the
digestive tract. In the stomach, this motion mixes
food with gastric juices, turning it into a thin liquid.
peritoneal
Having to do with the peritoneum.
peritoneal dialysis
A dialysis technique that
uses the patient’s own body tissues inside the
abdominal cavity as a filter. A plastic tube called a
dialysis catheter is surgically placed through the
abdominal wall, into the abdominal cavity. A special
fluid is then flushed into the abdominal cavity and
washed around the intestines. The intestinal walls
act as a filter between this fluid and the blood-
stream. By using different types of solutions, waste
products and excess water can be removed from the
body. This form of dialysis can be done either
manually or by machine at home, thereby avoiding
hospitalization or receiving dialysis treatment at a
dialysis center.