Cannula use in laser lipo
The cannula is a metal tube that acts as a protective sleeve for the laser fiber and prevents excessive bending that could cause the laser fiber to "fracture."
To give you a simple analogy: If you think of a mechanical pencil, the metal part of the pencil protects the lead and you advance only a small portion of the lead to keep from fracturing it. If you tried to write with the lead itself it would break. you need the metal sleeve (cannula) to protect the delicated lead.