1. Field of the Invention
The present invention generally relates to surgical tools and systems which will be controlled by a computer but which will provide feedback to the surgeon.
2. Background Description
Minimally invasive surgery generally describes a process for conducting surgical procedures such as cutting, scraping, activating, etc. inside the body of a subject without having to open an area in the subject to allow the surgeon access to a site or location. Examples of minimally invasive surgery include any endoscopic device with an actuator, i.e., an instrument which is deployed into a body canal, organ, etc., which enables, for example, visual observation on a display of the area around the endoscopic device (some tools do not utilize visual imaging) and which allows selective control of an actuatable device extending from the endoscopic tool. For example, balloon catheters are used in heart surgery under the control of the surgeon that views the position of the catheter inside an artery on a display. The surgeon can selectively actuate a balloon inside the artery at a desired location. A variety of other actions can also be taken such as deployment of a stent, administration of pharmaceuticals at a desired location, etc.
One of the requirements for minimally invasive surgery is that the instruments that are deployed be quite small. Mechanical cutting tools have been miniaturized for these types of surgeries, but suffer from a necessary bulk required for mechanical linkages and other actuation mechanisms. Piezoelectric materials, shape memory alloys, and ionic polymer actuators have also been employed. For example, piezoelectric ultrasonic generators have been used in endodontics, periodontology, bone osteomy, and maxillofacial surgery. Piezoelectric bimorphs have also been used to function as grippers and sensors in robotic surgical devices. Thin film piezoelectric patches have been used on angioplasty balloons for measuring the thickness of arterial plaque. Smart memory alloys such as Nitinol have been used in self-expanding heart stents and in implantable heart valves. Shape memory alloys are also being developed for applications as replacement tissues and filters. Ionic polymer actuators have been suggested for use in fixation devices and in surgical stapling applications.
While there have been many advances allowing for the use of computer controlled actuators, surgery still requires the sound judgment of a skilled surgeon. For example, he or she will need the ability to make fine and precise cuts without damaging other tissues, organs, nerves, etc. in the regions where the cuts are made. A distinct impediment to the advancement of minimally invasive surgery is the ability to provide the surgeon with feedback that allows the surgeon to know exactly what is going on at the surgical site.