Many people use the terms ocean and sea interchangeably when speaking about the ocean, but there is a difference between the two terms when speaking of geography (the study of the Earth's surface).
The peritoneal dialysis catheter is composed of a flexible silicone tube with an open-end port and several side holes to provide optimal drainage and absorption of the dialysate. The extraperitoneal component of the catheter has either one or two Dacron cuffs. The Dacron cuffs are for optimal ingrowth and fixation.
A lumbar-peritoneal shunt is a piece of tubing inserted through a surgical procedure performed to relieve pressure in areas of the brain and spinal cord caused by a buildup of fluid applying pressure to the brain. This form of shunt is commonly used to treat intracranial hypertension and the resulting symptoms of vision loss and persistent headaches.