· An endoscope is a device used in medicine to see inside the body.
· An intense light ray enters a long section of glass at a precise angle, this results in total internal refraction.
· Two bundles of fibres consisting of thin flexible glass rods are used in an endoscope; one carries the light beam to the object that is being viewed. The other carries the reflected image to the persons eye.
· Endoscopes are covered in soft material so that they can be inserted into the body through natural openings such as the mouth. They can also be inserted through a small incision (This is called keyhole surgery)
· Endoscopes are used to examine patient’s oesophagus, stomach, respiratory tract and so on. It is a non-invasive technique, because surgery is not required and it can be used on pregnant women.
· Pulse oximetry is a non-invasive method that is used to determine the amount of oxygen carried by the haemoglobin in the person’s blood.