For deep brain regions (0 mm to 8 mm deep), use the Twist-on efocus Imaging Cannula Model L that brings the image from inside the brain to the skull surface with an image guiding gradient-index rod lens. The Twist-on efocus Imaging Cannulas are compatible with Twist-on efocus Fluorescence Microscope Bodies only.

The different depth ranges of brain tissue are accessed with different lens lengths while fine adjustment is done with the protrusion adjustment rings that come with each cannula. It is recommended to use the smallest lens for the desired depth for a higher stability and image quality. Two diameters of GRIN lenses are available: 500 µm diameter GRIN lens offers smaller footprint while 1000 µm diameter lens provides a larger field of view.

Prism tip implant allows to image a transversal section of the brain (prism orientation on option): 

• Each Twist-on Imaging Cannula is provided with one of each of the five models of Protrusion Adjustment Rings Model L. If more rings are needed, a set can be purchased separately (PARS_L).
• 500 microns diameter GRIN lenses with prism tip are now protected with a metallic tubing (outer diameter 750 um). Imaging cannula with prism tip are still available without the metallic protection on custom request (contact sales@doriclenses.com)