Quick cycle biopsy system

Abstract

A method for using a biopsy device includes providing a housing, a cannula, a cutting sheath, a pressure generating device, and a valve. The pressure generating device is configured to selectively generate each of a positive pressure and a negative pressure. The valve is positioned in the housing and positioned in fluid communication between the cannula and the pressure generating device to control a fluid flow between the lumen of the cannula and the pressure generating device such that each of the positive pressure and the negative pressure selected is controlled by the valve. The method includes operating the valve to build up the selected positive pressure or negative pressure.

1 - 14 . (canceled) 
     
     
         15 . A method for using a biopsy device, comprising:
 providing a housing having a proximal end and a distal end;   providing a cannula positioned in the housing to extend through the distal end of the housing, the cannula having a closed penetrating tip and a side opening located on a circumferential surface of the cannula;   providing a cutting sheath positioned in the housing to extend through the distal end of the housing, the cutting sheath being slidably and coaxially disposed over the cannula to selectively cover the side opening of the cannula;   providing a pressure generating device positioned in the housing and connected to a proximal portion of the cannula for altering a pressure in a lumen of the cannula, the pressure generating device configured to selectively generate each of a positive pressure and a negative pressure, each of the positive pressure and the negative pressure relative to an atmospheric pressure;   providing a valve positioned in the housing and positioned in fluid communication between the cannula and the pressure generating device to control a fluid flow between the lumen of the cannula and the pressure generating device such that each of the positive pressure and the negative pressure selected is controlled by the valve; and   operating the valve to build up the selected positive pressure or negative pressure.   
     
     
         16 . The method of  claim 15 , wherein the valve is a bifurcated valve assembly interposed between the cannula and a pressure chamber of the pressure generating device, the bifurcated valve assembly having a first valve portion configured to release the selected positive pressure or the selected negative pressure into the lumen of the cannula and having a second valve portion coupled between the first valve portion and the pressure chamber, the second valve portion configured to facilitate an inflow of air into the pressure chamber. 
     
     
         17 . The method of  claim 15 , wherein the pressure generating device includes a single acting cylinder with a piston slidably disposed within the cylinder for displacing a volume of the fluid, a port positioned at a first end of the cylinder being connected to the valve, and an orifice on the cylinder to facilitate an air inflow into the cylinder when the piston is displaced to a second end of the cylinder. 
     
     
         18 . The method of  claim 15 , comprising partially obstructing the lumen proximal to the side opening. 
     
     
         19 . The method according to  claim 15 , comprising providing a seal between the cannula and the cutting sheath. 
     
     
         20 . The method according to  claim 15 , further comprising:
 generating the negative pressure in the pressure generating device;   opening the valve to deliver the negative pressure from the pressure generating device to the cannula;   displacing the cutting sheath in the proximal direction to selectively uncover the side opening and in the process, suctioning a tissue through the side opening;   displacing the cutting sheath distally to selectively cover the side opening of the cannula and in the process of displacing the cutting sheath distally, the cutting sheath separates a tissue sample from the tissue a body of a patient;   removing the cannula containing the tissue sample from the patient;   closing the valve;   generating the positive pressure in the pressure generating device;   opening the valve to apply the positive pressure from the pressure generating device to the cannula while the side opening is covered with the cutting sheath; and   after applying the positive pressure to the cannula, ejecting the tissue sample out of the cannula by sliding the cutting sheath to at least partially uncover the side opening.   
     
     
         21 . The method according to  claim 15 , wherein the pressure generating device comprises a chamber, the chamber comprising a proximal air inlet, a distal port in communication with the cannula, and a piston slidably disposed within the chamber. 
     
     
         22 . The method according to  claim 21 , further comprising:
 generating the negative pressure in the chamber by displacing the piston in a proximal direction toward the proximal end of the housing;   normalizing the negative pressure in the chamber by displacing the piston past the air inlet in the proximal direction; and   generating the positive pressure in the chamber by displacing the piston past the air inlet in a distal direction toward the distal end of the housing.   
     
     
         23 . The method according to  claim 22 , further comprising:
 applying the negative pressure generated in the chamber to the cannula;   displacing the cutting sheath in the proximal direction to selectively uncover the side opening and in the process, suctioning a tissue through the side opening;   displacing the cutting sheath distally to selectively cover the side opening of the cannula and in the process of displacing, the cutting sheath separates a tissue sample from the tissue a body of a patient;   removing the cannula containing the tissue sample from the patient;   applying the positive pressure generated in the chamber to the cannula while the side opening is covered with the cutting sheath; and   after generating the positive pressure, ejecting the tissue sample out of the cannula by sliding the cutting sheath to at least partially uncover the side opening.   
     
     
         24 . A method for using a biopsy device, comprising:
 providing a housing having a proximal end and a distal end;   providing a cannula positioned in the housing to extend through the distal end of the housing, the cannula having a closed penetrating tip, a side opening located on a circumferential surface of the cannula, a cannula proximal end, and a lumen extending from the closed penetrating tip and the cannula proximal end;   providing a cutting sheath positioned in the housing to extend through the distal end of the housing, the cutting sheath being slidably and coaxially disposed over the cannula to selectively cover the side opening of the cannula;   providing a pressure generating device positioned in the housing and coupled to the proximal end of the cannula, the pressure generating device configured to selectively generate each of a positive pressure and a negative pressure, each of the positive pressure and the negative pressure relative to an atmospheric pressure;   providing a valve configured to control a fluid flow between the lumen of the cannula and the pressure generating device by positioning the valve in the housing between the proximal end of the cannula and the pressure generating device, the valve being coupled to an actuator;   operating the pressure generating device to generate a first pressure selected from the group of the positive pressure and the negative pressure;   operating the valve via the actuator to build up the first pressure.   
     
     
         25 . The method according to  claim 24 , further comprising operating the valve to release the first pressure to the lumen of the cannula. 
     
     
         26 . The method according to  claim 24 , wherein the first pressure is the negative pressure,
 displacing the cutting sheath distally to selectively cover the side opening of the cannula and in the process of displacing the cutting sheath distally, the cutting sheath separates a tissue sample from the tissue a body of a patient; and   removing the cannula containing the tissue sample from the patient.   
     
     
         27 . The method according to  claim 26 , further comprising:
 normalizing the negative pressure in the pressure generating device;   generating the positive pressure in the pressure generating device;   operating the valve to build up the positive pressure in the pressure generating device;   operating the valve to apply the positive pressure generated in the pressure generating device to the cannula while the side opening is covered with the cutting sheath; and   sliding the cutting sheath to at least partially uncover the side opening, the step of sliding the cutting sheath resulting in the ejection of the tissue sample out of the cannula.   
     
     
         28 . A method for using a biopsy device, comprising:
 providing a housing having a proximal end and a distal end;   providing a cannula positioned in the housing to extend through the distal end of the housing, the cannula having a closed penetrating tip, a side opening located on a circumferential surface of the cannula, a cannula proximal end, and a lumen extending from the closed penetrating tip and the cannula proximal end;   providing a cutting sheath positioned in the housing to extend through the distal end of the housing, the cutting sheath being slidably and coaxially disposed over the cannula to selectively cover the side opening of the cannula;   providing a pressure generating device positioned in the housing and coupled to the proximal end of the cannula;   providing a valve in the housing between the proximal end of the cannula and the pressure generating device, the valve coupled to an actuator;   generating a selected pressure from the group of a positive pressure and a negative pressure in the pressure generating device, each of the positive pressure and the negative pressure relative to an atmospheric pressure; and   operating the actuator and the valve to selectively control a fluid flow between the lumen of the cannula and the pressure generating device.   
     
     
         29 . The method of  claim 28 , comprising partially obstructing the lumen proximal to the side opening. 
     
     
         30 . The method of  claim 28 , wherein the pressure generating device includes a single acting cylinder with a piston slidably disposed within the cylinder for displacing a volume of the fluid, a port positioned at a first end of the cylinder being connected to the valve, and an orifice on the cylinder to facilitate an air inflow into the cylinder when the piston is displaced to a second end of the cylinder. 
     
     
         31 . The method of  claim 28 , operating the valve to build up the selected pressure, wherein the valve is a bifurcated valve assembly interposed between the cannula and a pressure chamber of the pressure generating device, the bifurcated valve assembly having a first valve portion configured to release the selected pressure into the lumen of the cannula and having a second valve portion coupled between the first valve portion and the pressure chamber, the second valve portion configured to facilitate an inflow of air into the pressure chamber. 
     
     
         32 . The method of  claim 28 , comprising:
 providing a seal between the cannula and the sheath;   providing a first connection element connecting the proximal end of the cannula and the valve; and   providing a second connection element connecting the valve and the pressure generating device.   
     
     
         33 . The method of  claim 28 , wherein the pressure generating device comprises a chamber, the chamber comprising a proximal air inlet, a distal port in communication with the cannula, and a piston slidably disposed within the chamber. 
     
     
         34 . The method of  claim 33 , further comprising:
 generating the negative pressure in the chamber by displacing the piston in a proximal direction toward the proximal end of the housing;   normalizing the negative pressure in the chamber by displacing the piston past the air inlet in the proximal direction; and   generating the positive pressure in the chamber by displacing the piston past the air inlet in a distal direction toward the distal end of the housing.