Cannula and Proximally Mounted Camera with an Imaging Control System for Rotating Images

Abstract

A cannula system with a proximally mounted camera assembly, sensors or sensor pair component(s), radially fixed to the camera assembly and an image control system operable to rotate image data obtained from the camera for display on a display screen, to maintain an image in an orientation preferred by a surgeon even as the camera assembly is rotated radially about the axis of the cannula.

We claim: 
     
         1 . A cannula system for accessing a surgical field, said cannula comprising:
 a cannula comprising a cannula tube with a proximal end and a distal end and a lumen extending from the proximal end to the distal end, said proximal end of the cannula having a rim, said lumen configured to allow passage of surgical tools from the proximal end of the cannula tube to the distal end of the cannula tube; and   a camera assembly secured to the rim of the proximal end of the cannula, with a portion of the camera assembly overhanging the lumen and extending into a cylindrical space defined by the lumen of the cannula tube and extending therefrom;   a display screen;   sensing means for generating signals corresponding to a position of the camera assembly on the rim, relative to an axis of the cannula tube; wherein   an image control system operable to receive image data from the camera assembly and generate corresponding images for display on the display screen, and operable to display said images in an initial preferred orientation, and operable to rotate the image, in response to rotation of the camera assembly on the rim relative to the axis of the cannula tube, to continue to present images of the surgical space in the initial preferred orientation; and   the image control system is configured to receive input from a user indicating that the camera assembly is in a first radial position relative to the cannula tube and rim of the proximal end of the cannula tube and display an image received from the camera assembly of the surgical field in an initial orientation corresponding to said first radial position on the display screen, and thereafter receive signals from the sensing means corresponding to the position of the camera assembly on the rim relative to the axis of the cannula tube, and determine that the camera assembly is in a second position on the rim relative to the axis if the cannula tube and receive a second image from the camera assembly, and, based on this determination, rotate the second image presented on the display screen to present the second image in the initial orientation.   
     
     
         2 . The cannula system of  claim 1  wherein:
 the image control system is operable, at the selection of a user, set an initial orientation of images obtained the camera, as determined by the sensing means and as selected by a user, as an initial preferred orientation, and thereafter process the image obtained from the camera assembly after the camera has been rotated to a second position to present a rotated image on the display, where said rotated image is presented in the same orientation as the images presented from the cannula in the initial preferred orientation. 
 
     
     
         3 . The cannula system of  claim 1  wherein:
 the sensing means comprises an accelerometer assembly operable to provide a signal corresponding to radial motion of the camera about a plane defined by the mounting structure or proximal edge of the cannula tube 
 
     
     
         4 . The cannula system of  claim 1  wherein:
 the sensing means comprises an accelerometer assembly operable to provide a signal corresponding to radial motion of the camera about a plane perpendicular to the long axis of the cannula tube 
 
     
     
         5 . The cannula system of  claim 1  wherein:
 the sensing means comprises an encoder operable to provide a signal corresponding to the radial position of the camera relative to the cannula tube 
 
     
     
         6 . The cannula system of  claim 1  wherein:
 the sensing means comprises a rheostat operable to provide a signal corresponding to the radial position of the camera relative to the tube; 
 
     
     
         7 . The cannula system of  claim 1  wherein:
 the sensing means comprises a gyroscope operable to provide a signal corresponding to motion of the camera about the plane defined by the mounting structure or proximal edge of the cannula tube 
 
     
     
         8 . The cannula system of  claim 1  wherein:
 the sensing means comprises a gyroscope operable to provide a signal corresponding to radial motion of the camera about a plane perpendicular to the long axis of the cannula tube 
 
     
     
         9 . The cannula system of  claim 1  wherein:
 the sensing means comprises neuronavigation markers, which, together with a neuronavigation system are operable to provide a signal corresponding to radial motion of the camera about the cannula tube. 
 
     
     
         10 . The cannula system of  claim 1  further comprising:
 an input means for receiving input from the user. 
 
     
     
         11 . The cannula system of  claim 10  wherein:
 the image control system is operable, at the selection of a user, to rotate the image on the display to an orientation matching an orientation of an initial preferred orientation selected by a user. 
 
     
     
         12 . The cannula system of  claim 1  wherein:
 the image control system is further configured to receive input from a user and, in response to said input, rotate an image presented on the display so that the image presented on the display is a first rotated image rotated relative to the image received by the camera corresponding to an initial preferred orientation, and thereafter perform the step of receiving second images from the camera assembly rotating the second image presented on the display to present the second image in the initial preferred orientation.