Apparatus and method for image guided insertion and removal of a cannula or needle

Abstract

A means for holding a selected cannula such that the cannula is controllably restricted in motion in all but one line, but still able to slide along the line relatively freely. The motion restricting force may be selectively varied, thereby allowing an unrestricted separation of the cannula and the holding/guide device.

1 . An imaging guided device for placing a cannula attached to a magnetically responsive needle at a targeted location, the device comprising:
 an imaging probe operationally configured with imaging system to present an image;   an attachment connected with the imaging probe, the attachment comprising:
 a block having at least one magnet to releasably retain the needle by alternating the magnetic force of the magnet applied to the needle, 
   wherein the needle is inserted to and removed from the targeted location as determined in the image at a user adjusted retentive magnetic force, leaving the cannula in place at the targeted location after removal of the needle.   
   
   
       2 . The device of  claim 1 , wherein the magnet comprises at least one removable strip. 
   
   
       3 . The device of  claim 1 , wherein the magnet comprises two removable strips approximately orthogonal to each other. 
   
   
       4 . The device of  claim 3 , wherein the removable strip includes a plurality of magnets having substantially similar magnetic power. 
   
   
       5 . The device of  claim 3 , wherein the removable strip includes a plurality of magnets having substantially different magnetic power. 
   
   
       6 . The device of  claim 5 , wherein the removable strip includes an inner magnetic core and an outer magnetic perimeter. 
   
   
       7 . The device of  claim 1 , wherein the magnet includes a ferrite core having a first gap to engage a moveable magnet bar and a second gap to receive the magnetically responsive needle. 
   
   
       8 . The device of  claim 7 , wherein the moveable magnet bar is slidable within the first gap. 
   
   
       9 . The device of  claim 7 , wherein the moveable magnet bar is translocatable from the first gap. 
   
   
       10 . The device of  claim 7 , wherein the moveable magnet bar is rotatable within the first gap. 
   
   
       11 . The device of  claim 1 , wherein the magnet includes a magnetic core having a first gap to engage a moveable magnet bar and a second gap to receive the magnetically responsive needle. 
   
   
       12 . The device of  claim 11 , wherein the moveable magnet bar is rotatable within the first gap. 
   
   
       13 . A system for visualizing a medical object trajectory comprising:
 a processing and display generating system;   an ultrasound probe for scanning tissue in signal communication with the processing and display generating system; and   at least one camera for capturing at least one image of a medical object in signal communication with the processing and display generating system,   wherein the processing and display generating system is configured to process signals received from the ultrasound probe, display an ultrasound image of the tissue, process signals received from the at least one camera to determine a trajectory of the medical object, and display a representation of the determined trajectory of the medical object on the ultrasound image.   
   
   
       14 . The system of  claim 13 , wherein the at least one camera includes a first camera that takes images of the medical object in a first direction and a second camera that takes images of the medical object in a second direction. 
   
   
       15 . The system of  claim 14 , wherein the first and second cameras are in a fixed position relative to the ultrasound probe. 
   
   
       16 . The system of  claim 15 , wherein the second direction is orthogonal to the first direction. 
   
   
       17 . The system of  claim 14 , wherein the medical object includes a cannula. 
   
   
       18 . The system of  claim 14 , wherein the medical object includes a plurality of reflectors and wherein the processing and display generating system is configured to determine a trajectory of the medical object based on light reflected by the plurality of reflectors. 
   
   
       19 . The system of  claim 18 , wherein the medical object includes a needle having a bevel, at least one of the reflectors is located near the bevel, and the processing and display generating system is configured to determine a trajectory of the bevel. 
   
   
       20 . The system of  claim 19 , wherein the processing and display generating system is configured to display a cross-sectional image of a target vein located within the scanned tissue on the ultrasound image and wherein the processing and display generating system is configured to display a representation of the determined trajectory of the medical object on the ultrasound image. 
   
   
       21 . The system of  claim 20 , wherein the representation of the determined trajectory includes cross-hairs. 
   
   
       22 . The system of  claim 21 , further comprising an illumination source for illuminating the medical object during image capture. 
   
   
       23 . The system of  claim 22 , wherein the illumination source includes infrared light emitting diodes. 
   
   
       24 . The system of  claim 14 , wherein at least one of the first and second cameras are configured to capture images of a portion of the medical object when the portion is in a sub-dermal location. 
   
   
       25 . A method for visualizing a medical object trajectory comprising:
 scanning tissue using an ultrasound probe;   displaying an ultrasound image of the tissue;   capturing at least one image of a medical object using at least one camera;   processing the at least one image to determine a trajectory of the medical object; and   displaying a representation of the determined trajectory of the medical object on the ultrasound image.