Using imaging techniques, radiologists were able to direct interventional instruments through the body by way of catheters instead of the large incisions needed in traditional surgery.

[2] Diagnostic techniques that do not involve incisions, puncturing the skin, or the introduction of foreign objects or materials into the body are known as non-invasive procedures.

Many other minimally invasive procedures have followed where images of all parts of the body can be obtained and used to direct interventional instruments by way of catheters (needles and fine tubes), so that many conditions once requiring open surgery can now be treated non-surgically.

[2] A minimally invasive procedure typically involves the use of arthroscopic (for joints and the spine) or laparoscopic devices and remote-control manipulation of instruments with indirect observation of the surgical field through an endoscope or large scale display panel, and is carried out through the skin or through a body cavity or anatomical opening.

[6] Many medical procedures are called minimally invasive; those that involve small incisions through which an endoscope is inserted, end in the suffix -oscopy, such as endoscopy, laparoscopy, arthroscopy.

The images of the interior of the body are transmitted to an external video monitor and the surgeon has the possibility of making a diagnosis, visually identifying internal features and acting surgically on them.

With tissues and structures exposed to the air, the procedure can be performed either with the unaided vision of the surgeon or with the use of loupes or microscopes.