Mri biopsy apparatus incorporating an imageable penetrating portion

Abstract

An obturator as part of a biopsy system enhances use with Magnetic Resonance Imaging (MRI) by indicating location of a side aperture in an encompassing cannula. The cannula (e.g., detached probe, sleeve sized to receive a core biopsy probe) includes a side aperture for taking a tissue sample. When the obturator is inserted in lieu of the biopsy device into the cannula, a notch formed in a shaft of the obturator corresponds to the side aperture. A dugout trough into the notch may further accept aqueous material to further accentuate the side aperture. In addition, a series of dimensionally varied apertures (e.g., wells, slats) that communicate through a lateral surface of the shaft and that are proximal to the side aperture receive an aqueous material to accentuate visibility in an MRI image, even in a skewed MRI slice through the cannula/obturator.

What is claimed is: 
     
         1 - 20 . (canceled) 
     
     
         21 . An apparatus for use with a minimally invasive medical procedure in human breast tissue, the apparatus comprising:
 (a) a cannula formed of a magnetic resonance imaging (MRI) compatible material, wherein the cannula includes:
 (i) a lateral opening proximal to a distal end, and 
 (ii) a longitudinal lumen sized to receive a core biopsy cutting member; and 
   (b) an obturator including:
 (i) a shaft formed of an MRI compatible material and sized for insertion into the cannula in lieu of the core biopsy cutting member, 
 (ii) an MRI imageable recess formed in the shaft of the obturator and operably configured to receive an Mill visible material, and 
 (iii) a plurality of transverse wells disposed within the shaft and longitudinally spaced proximally relative to the MRI imageable recess, wherein the plurality of transverse wells are in communication with an exterior of the obturator. 
   
     
     
         22 . The apparatus of  claim 21 , wherein the MRI imageable recess includes a flat notch in profile. 
     
     
         23 . The apparatus of  claim 22 , wherein the MRI imageable recess further includes a trough formed in the flat notch. 
     
     
         24 . The apparatus of  claim 21 , wherein the MRI imageable recess of the obturator is positioned to be coincident with the lateral opening of the cannula when the obturator is inserted into the cannula. 
     
     
         25 . The apparatus of  claim 21 , wherein each of the plurality of lateral wells includes a distinct shape from the other lateral wells. 
     
     
         26 . The apparatus of  claim 21 , wherein the plurality of lateral wells includes a plurality of cylindrical wells. 
     
     
         27 . The apparatus of  claim 21 , wherein the plurality of lateral wells includes a plurality of slats. 
     
     
         28 . The apparatus of  claim 27 , wherein each of the plurality of slats has a distinct shape from the others. 
     
     
         29 . The apparatus of  claim 21 , wherein a selected one of the plurality of lateral wells is filled with an aqueous material. 
     
     
         30 . The apparatus of  claim 29 , wherein a selected one of the plurality of lateral wells is filled with saline. 
     
     
         31 . The apparatus of  claim 29 , wherein a selected one of the plurality of lateral wells is filled with an aqueous gel. 
     
     
         32 . The apparatus of  claim 21 , wherein a selected one of the plurality of lateral wells is filled with a hydrophilic polymer. 
     
     
         33 . The apparatus of  claim 21 , wherein the cannula includes an open distal end, the obturator further including a distally attached piercing tip. 
     
     
         34 . The apparatus of  claim 33 , wherein the piercing tip includes a PEEK material. 
     
     
         35 . The apparatus of  claim 33 , wherein the piercing tip includes an over-molded ceramic tip. 
     
     
         36 . An apparatus for use with a minimally invasive medical procedure in human breast tissue, the apparatus comprising:
 (a) a cannula formed of a magnetic resonance imaging (MRI) compatible material, the cannula including:
 (i) a lateral opening proximal to a distal end, and 
 (ii) a longitudinal lumen sized to receive a core biopsy cutting member; and 
   (b) an obturator including a shaft formed of an MRI compatible material and sized for insertion into the cannula in lieu of the core biopsy cutting member, wherein the obturator further includes an MRI imageable lumen extending longitudinally within the obturator and operably configured to receive an MRI visible fluid, wherein the MRI imageable lumen further includes:
 (i) a first end disposed proximally relative to the lateral opening of the cannula, 
 (ii) a second end disposed proximally relative to the first end, and 
 (iii) a plurality of vent openings disposed longitudinally along the shaft of the obturator, wherein the vent openings are oriented transversely relative to the MRI imageable lumen, wherein each vent opening of the plurality of vent openings is in communication with the MRI imageable lumen. 
   
     
     
         37 . The apparatus of  claim 36 , wherein each vent opening of the plurality of vent openings communicates with an exterior of the obturator. 
     
     
         38 . The apparatus of  claim 36 , wherein each vent opening of the plurality of vent openings is disposed proximally relative to the lateral opening of the cannula, wherein the at least one vent opening is operably configured to pass air from within the MRI imageable lumen to outside the MRI imageable lumen. 
     
     
         39 . The apparatus of  claim 36 , wherein the cannula includes an open distal end, the obturator further including a distally attached piercing tip. 
     
     
         40 . An apparatus for use with a minimally invasive medical procedure into human breast tissue, the apparatus comprising:
 (a) a cannula formed of a magnetic resonance imaging (MRI) compatible material, the cannula including:
 (i) a lateral opening proximal to a distal end, and 
 (ii) a longitudinal lumen sized to receive a core biopsy cutting member; and 
   (b) an obturator formed of an MRI compatible material and sized for insertion into the cannula in lieu of the core biopsy cutting member, wherein the obturator includes:
 (i) a sharp distal tip, 
 (ii) an imageable side notch disposed proximally adjacent to the sharp distal tip, and 
 (iii) a plurality of transverse wells, wherein the wells are disposed longitudinally along the length of the obturator, wherein each well decreases in diameter in a pattern moving proximally from the imageable side notch.