Brachytherapy instrument and methods

A brachytherapy device, comprising:

• an elongated needle having a sharp end for insertion into target tissue;
• an elongated stylet which can slide through the needle;
• and
• a housing that selectively engages the needle and stylet to selectively fix the needle and stylet against axial movement, wherein relative rotation between the housing and needle selectively engages the needle to the housing to fix the needle against axial movement relative to the housing, and relative rotation between the housing and the stylet selectively engages the stylet to the housing to fix the stylet against axial movement relative to the housing.

A brachytherapy device, comprising:

• an elongated needle having a sharp end for insertion into target tissue;
• an elongated stylet which can slide through the needle;
• and
• a housing that selectively engages the needle to selectively fix the needle against axial movement, wherein rotation of the needle relative to the housing selectively engages the needle to the housing to fix the needle against axial movement relative to the housing, whereby rotation of the needle also reduces frictional engagement between the needle and the target tissue.

A needle stop for use in a brachytherapy procedure to prevent a needle extending in an axial direction from advancing beyond a predetermined position, the needle stop comprising a body extending transverse to the axial direction and having:

• a needle receiving side with a plurality of slots formed therein in a direction perpendicular to the axial direction, each of the slots being sized to allow a shaft of a needle to pass therethrough as the needle is inserted;
• a needle stop surface on the needle receiving side that stops insertion of the needle through contact by an enlarged portion of the needle with the stop surface;
• and
• an attachment portion that allows the needle stop to be attached to an object.

A needle guide through which a brachytherapy needle having a needle tip can be inserted, the needle guide comprising:

• a stationary first member having a first plurality of apertures extending in an axial direction and sized to allow the needle shaft to pass therethrough;
• and
• a second member that is coupled to the first member for movement in a direction of needle insertion, the second member having a second plurality of apertures corresponding to the first plurality of apertures, the second plurality of apertures being dimensioned smaller than the needle shaft;
• whereby the second member receives a tip of a needle inserted through the first member from the insertion side and into one of the second plurality of apertures, the second member moving with and guiding the tip as the needle advances in the axial direction.

A method of implanting brachytherapy seeds, the method comprising:

• providing an elongated needle having a sharp end for insertion into target tissue, an elongated stylet which can slide through the needle, and a housing that selectively engages the needle to selectively fix the needle against axial movement by rotating the needle;
• rotating the needle to engage the needle with the housing;
• inserting brachytherapy seeds into the needle;
• inserting the stylet into the needle to advance the seeds toward a sharp end of the needle;
• inserting the needle into the target tissue;
• rotating the needle to disengage the needle from the housing and permit axial movement of the needle;
• and
• withdrawing the needle over the stylet to implant the seeds in the target tissue.

A method of performing a brachytherapy treatment using an instrument, the instrument comprising:

• a hollow needle having a needle tip that defines a distal end of the instrument, a needle shaft that defines a central axis of the instrument and a needle extension portion joined to the proximal end of the needle shaft, the needle shaft containing seeds to be implanted within a patient's body;
• a stylet inserted through the needle extension portion and into the needle shaft, the stylet having a distal end in contact with a most proximal seed and a proximal end with a stylet hub adjacent the needle extension portion;
• a housing extending partially around the central axis and within which the needle extension portion and the stylet hub are rotatably coupled, the housing having a distal end through which the needle shaft extends and a proximal end through which the needle extension portion extends;
• the method comprising:
• advancing the instrument in an axial direction to insert the needle into the body;
• engaging the stylet with the housing to cause the stylet to advance in the axial direction relative to the needle by a predetermined distance to implant the most distal seed;
• disengaging the needle from the housing;
• and
• retracting the needle in the axial direction relative to the stylet and the housing, which remain stationary, to implant remaining seeds.