MRI compatible biopsy device with detachable probe

Abstract

A Magnetic Resonance Imaging (MRI) compatible core biopsy instrument includes a detachable probe assembly to enhance the accuracy of placement at a biopsy site and avoid repeated insertions, even when used in a closed MRI magnet bore. In particular, the detachable probe assembly is configured for attachment to a localization fixture for accurate stereotopic placement to the desired biopsy site. While disengaged, dual lumens (vacuum and cutter) of the probe assembly allow applying vacuum to, draining fluid from, and insertion of fluids to the biopsy site. The biopsy instrument handle readily engages to the probe assembly for taking samples. Features are included for visual indications of the position of the cutter, prevention of disengagement when the cutter is advanced into the probe assembly, and a tolerance take-out feature that minimizes the deadzone gap at a distal end of the probe assembly, allowing samples to be taken close to sensitive tissues.

What is claimed is:  
     
         1 . A biopsy device, comprising: 
 a detachable probe assembly comprising: 
 an elongated substantially tubular needle having a distal end for insertion within tissue, a proximal end, and a longitudinal axis therebetween, a cutter opening laterally placed near the distal end, and  
 an engagement device coupled to the proximal end of the needle, the engagement device including a cutter access port aligned to the longitudinal axis of the needle; and  
   a cutter member comprising: 
 a locking device configured to selectably lock to the engagement device of the detachable insertion member, and  
 an actuating cutter for reciprocating advancement and withdrawal through the needle.  
   
     
     
         2 . The biopsy device of  claim 1 , wherein the needle of the detachable probe assembly further includes a vacuum chamber lumen in fluid communication between the cutter opening and the proximal end.  
     
     
         3 . The biopsy device of  claim 1 , wherein the detachable insertion member is compatible for use with a magnetic resonance imaging machine, including non-ferromagnetic materials.  
     
     
         4 . The biopsy device of  claim 1 , wherein the detachable insertion member further comprises a vacuum port in fluid communication with the longitudinal axis for transferal of fluids.  
     
     
         5 . The biopsy device of  claim 1 , further comprising: 
 an obturator stylet shaped to receive and seal at least the proximal end of the longitudinal axis of the needle when the cutter member is removed from the detachable insertion member.    
     
     
         6 . The biopsy device of  claim 5 , wherein the needle of the detachable probe assembly further includes a vacuum chamber lumen in fluid communication between the cutter opening and the proximal end, and. wherein distal portion of the obturator stylet includes through holes to allow the cutter opening to be in fluid communication with the vacuum chamber lumen.  
     
     
         7 . The biopsy device of  claim 1 , wherein the locking device of the cutter member is further configured to prevent unlocking when the actuating cutter is inserted into the needle.  
     
     
         8 . The biopsy device of  claim 1 , wherein the cutter member further comprises a vacuum extraction system for selectably withdrawing a cut piece of tissue through the needle.  
     
     
         9 . The biopsy device of  claim 1 , wherein the cutter member further includes an insertion indicator that provides a visual indication to an operator as to a depth of insertion of the cutter  
     
     
         10 . The biopsy device of  claim 1 , further comprising a tolerance take-out device for eliminating longitudinal slack between the engagement device and the locking device, thereby minimizing a deadzone length at the distal end of the needle.  
     
     
         11 . The biopsy device of  claim 10 , wherein the tolerance take out device comprises a translating member coupled to advance with the actuating cutter and dimensioned to impart distally directed motion to the engagement member.  
     
     
         12 . The biopsy device of  claim 1 , further comprising 
 a tip protector including: 
 an attachment member selectably engageable onto the distal end of the tubular needle and having a recess exposing at least a portion of the cutter opening, and  
 a protection member coupled to the attachment member and shaped to encompass the distal end of the tubular needle.  
   
     
     
         13 . The biopsy device of  claim 1 , further comprising 
 a tip protector including: 
 an attachment member selectably engageable onto the distal end of the tubular needle, and  
 a protection member coupled to the attachment member, shaped to encompass the distal end of the tubular needle, and including an image artifact producing material.  
   
     
     
         14 . The biopsy device of  claim 13 , wherein the attachment member of the tip protector further includes a recess exposing at least a portion of the cutter opening of the tubular needle.  
     
     
         15 . A Magnetic Resonance Imaging (MRI)-guided core biopsy system, comprising: 
 a core biopsy probe assembly;    an MRI breast coil including a localization fixture comprising: 
 a compression plate having apertures, and  
 a mounting device operably configured to connect to the probe assembly at a selected orientation to the compression plate and to guide the probe assembly in depth as inserted through a selected aperture;  
   a cutter device selectably attachable to the probe assembly to advance a cutter through the probe assembly to cut a tissue sample;    a control module operable to generate a translation motion and a rotation motion; and    a power cable connecting the translation motion and the rotation motion from the control module to the cutter of the cutter device.    
     
     
         16 . The MRI-guided core biopsy system of  claim 15 , wherein the core biopsy probe assembly includes a cutter lumen for receiving the cutter device, a sample opening in the cutter lumen to allow a tissue sample to enter the cutter lumen, and includes vacuum lumen in fluid communication with the sample opening and a proximal end of the probe assembly, and wherein the control module is further operable to produce a vacuum through the vacuum lumen.  
     
     
         17 . A core biopsy probe comprising: 
 an elongated substantially tubular needle having a distal end for insertion within tissue, a proximal end, and a longitudinal axis therebetween, the needle separated along the longitudinal axis into a cutter lumen and a vacuum lumen, a cutter opening laterally placed near the distal end of the cutter lumen and in fluid communication with the vacuum lumen; and    an engagement device coupled to the proximal end of the needle, the engagement device including a cutter access port aligned to the longitudinal axis of the needle; and a vacuum port in fluid communication with the vacuum lumen, the engagement device further including a attachment member transversely disposed to the longitudinal axis and configured to attach to a mounting device for maintaining a position of the probe with respect to a biopsy site location.    
     
     
         18 . The core biopsy probe of  claim 17 , further comprising 
 a tip protector including: 
 an attachment member selectably engageable onto the distal end of the tubular needle and having a recess exposing at least a portion of the cutter opening, and  
 a protection member coupled to the attachment member and shaped to encompass the distal end of the tubular needle, and including an image artifact producing material.  
   
     
     
         19 . The core biopsy probe of  claim 17 , wherein the distal end of the tubular needle includes a needle tip having a distally projecting cutting blade.  
     
     
         20 . the core biopsy probe of  claim 19 , wherein the distally projecting cutting blade comprises an X-shaped pointed cutting blade.