The respiratory system is divided into four components: the upper respiratory system, lower respiratory system, chest wall and diaphragm. Upper respiratory system: The upper respiratory system comprises all structures and passages involved in the conduction of air from outside the body to the larynx. This system includes the nose, mouth and structures within the hypopharynx.
There are two fundamentally different types of laser eye surgery: PRK and LASIK. Under these two categories, there are several different flavors or modifications of each type.For example, LASEK (with an E) is a newer type of PRK.here are two fundamentally different types of laser eye surgery: PRK and LASIK. Under these two categories, there are several different flavors or modifications of each type.
Cataract Surgery Basics. In cataract surgery, the lens inside your eye that has become cloudy is removed and replaced with an artificial lens (called an intraocular lens, or IOL) to restore clear vision.The procedure typically is performed on an outpatient basis and does not require an overnight stay in a hospital or other care facility.hankfully, modern cataract surgery is one of the safest and most effective surgical procedures performed today. More than 3 million cataract surgeries are performed in the United States every year, with the vast majority of these procedures produce excellent visual outcomes.