Medical ultrasonic imaging

• US 6,275,724 B1
• Filed: 11/13/1998
• Issued: 08/14/2001
• Est. Priority Date: 03/27/1998
• Status: Expired due to Term

• Current Assignee: Jomed Imaging Ltd. (JOMED NV)
• Original Assignee: Jomed Imaging Ltd. (JOMED NV)
• Inventors: Stenning, Anthony, Spencer, Timothy, Dickinson, Robert Julian
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): SHAW, SHAWNA JEANNINE
• Application Number:
  US09/191,796
• Time in Patent Office: 1,005 Days
• Field of Search: 600/424, 600/466, 600/585, 606/130, 128/899, 324/207.11, 324/207.13
• US Class Current: 600/424
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/067 using accelerometers or gyroscopes
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00

Abstract

A method of measuring the position of the tip of a catheter includes the steps of continuously monitoring the distance the catheter has travelled past a reference point, monitoring the orientation of the tip, and reconstructing the trajectory of the catheter tip.

Claims

1. A pull back device comprising a hand-held unit adapted to have a catheter passed therethrough and to be drawn therethrough by hand, the unit including:

a pinch-roller mechanism comprising a spindle for guiding the catheter;

a device which generates a signal in response to rotation of the spindle indicative of a length of the catheter that has passed therethrough;

an arrangement adapted to be mechanically connected to a Tuey valve in a manner to prevent movement therebetween; and

an electrical connection adapted to transmit the signal to a data processor.

2. A pull back device as claimed in claim 1 wherein the arrangement comprises a tubular extension arranged to have a valve clamped thereto.

3. A pull back device as claimed in claim 2 in which the hand-held unit is provided with a seal arrangement to prevent ingress of blood into the unit when in use.

4. A pull back device as claimed in claim 1 in which the hand-held unit is pre-mounted on the catheter.

5. A pull back device as claimed in claim 1 in which a guide wire is fixed in position external to the hand-held unit.

6. A method of measuring the position of a tip of a catheter, comprising the steps of:

generating a first data set of signals indicative of a distance a proximal end of the catheter which is outside of a patient has traveled past a reference point to provide a scalar trajectory length of the proximal end of the catheter;

generating a second data set of signals indicative of an orientation of the distal end of the catheter to provide a trajectory vector direction of the distal end of the catheter; and

combining the first and second data sets to construct a representation of a trajectory of the distal end of the catheter.

7. A method as claimed in claim 6 in which said step of generating a second data set of signals includes the step of monitoring the orientation of the tip by means of signals from gyroscopes mounted at or near a distal end of the catheter.

8. A method as claimed in claim 6 in which said step of generating a second data set of signals includes the step of monitoring the orientation of the tip by means of signals from accelerometers mounted at or near a distal end of the catheter.

9. A method as claimed in claim 6 in which said step of generating a second data set of signals includes the step of monitoring the orientation of the tip by detecting bends in the catheter using fluctuations in echoes from a patient'"'"'s artery.

10. A method as claimed in claim 6 in which said step of generating a second data set of signals includes the step of monitoring the orientation of the tip by creating a magnetic field in an area of the tip and detecting variations in the magnetic field as a result of changes in the orientation of the tip.