What is "n-localizer"

The N-localizer (aka N-bar) is a device that enables guidance of stereotactic surgery or radiosurgery using tomographic images that are obtained via medical imaging technologies such as X-ray computed tomography (CT), magnetic resonance imaging (MRI) or positron emission tomography (PET). The N-localizer comprises a diagonal rod that extends from the top of one vertical rod to the bottom of a second vertical rod, and is shaped like a capital "N" (Figure 1A). This device was invented in 1978 by the American physician and computer scientist Russell Brown.

This invention stimulated renewed interest in, and further development of, image-guided surgery, specifically, stereotactic surgery and radiosurgery. It has achieved widespread clinical use in the Brown-Roberts-Wells (BRW), Leksell, Kelly-Goerss and Cosman-Roberts-Wells (CRW) stereotactic instruments and in the Gamma Knife streotactic radiosurgery system.