Magnetically tracked surgical needle assembly

A needle assembly comprising:

• a needle stylet comprising an elongated hollow tube and a needle and wherein the elongated hollow tube extends along a first axis and comprises an open proximal end and a closed distal end, and wherein the needle is attached to the closed distal end of the elongated hollow tube and comprises a tip end that extends a first distance from the closed distal end of the elongated hollow tube along the first axis;
• a sensor assembly comprising an elongated body extending along a second axis, and a sensor placed at a second distance from the distal end of said elongated body and wherein said elongated body is shaped and dimensioned to be inserted into said elongated hollow tube so that the distal end of the elongated body is placed in contact with the closed distal end of the elongated hollow tube, and wherein said sensor is configured to measure position and angular orientation data when placed within an electromagnetic field;
• and
• a computing system for computing the position and angular orientation of the tip end of the needle by adding the sum of the first and the second distances to the measured position data and by adding the angular difference between the first and second axes to the measured angular orientation data, respectively.

A needle assembly comprising:

• a needle stylet comprising an elongated hollow tube and a needle and wherein the elongated hollow tube extends along a first axis and comprises an open proximal end and a closed distal end, and wherein the needle is attached to the closed distal end of the elongated hollow tube and comprises a tip end that extends a first distance from the closed distal end of the elongated hollow tube along the first axis;
• a sensor assembly comprising an elongated body extending along a second axis, and a sensor located at a second distance from the distal end of said elongated body and wherein said elongated body is shaped and dimensioned to be inserted into said elongated hollow tube so that the distal end of the elongated body is placed in contact with the closed distal end of the elongated hollow tube, and wherein said sensor is configured to measure position and angular orientation data when placed within an electromagnetic field;
• means for fixing the sensor's angular orientation within said elongated hollow tube to be coaxial with said first axis;
• and
• a computing system for computing the position of the tip end of the needle by adding the sum of the first and the second distances to the measured position data.

A needle assembly comprising:

• a needle stylet comprising an elongated hollow tube and a needle and wherein the elongated hollow tube extends along a first axis and comprises an open proximal end and a closed distal end, and wherein the needle is attached to the closed distal end of the elongated hollow tube and comprises a tip end that extends a first distance from the closed distal end of the elongated hollow tube along the first axis;
• a sensor assembly comprising an elongated body, a sensor located at the distal end of said elongated body and a stop-plug configured to be placed over the elongated body's distal end and wherein said elongated body is shaped and dimensioned to be inserted into said elongated hollow tube so that distal end of the stop-plug is in contact with the closed distal end of the elongated hollow tube and wherein said stop-plug comprises an outer diameter slightly smaller than the inner diameter of the elongated hollow tube and is configured to orient the elongated body coaxially with the elongated hollow tube and wherein the stop-plug comprises an inner diameter slightly larger than the outer diameter of the elongated body and is configured to receive and place the elongated body's distal end at a second distance from the stop-plug's distal end;
• and
• a computing system for computing the position of the tip end of the needle by adding the sum of the first and the second distances to the measured position data.