Detection of lead orientation

• US 10,265,531 B2
• Filed: 08/31/2016
• Issued: 04/23/2019
• Est. Priority Date: 09/01/2015
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Bokil, Hemant
• Primary Examiner(s): Holmes, Rex R
• Application Number:
  US15/252,438
• Publication Number:
  US 20170056678A1
• Time in Patent Office: 965 Days
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/12 Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0534 Electrodes for deep brain stimulation
• CPC Class Codes: A61N 1/3605 Implantable neurostimulators for stimulating central or peripheral nerve system
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37247 User interfaces, e.g. input or presentation means
• CPC Class Codes: G06T 2207/10072 Tomographic images
• CPC Class Codes: G06T 2207/30021 Catheter; Guide wire
• CPC Class Codes: G06T 7/74 involving reference images or patches

Abstract

Systems and methods for determining a rotational orientation of a lead for use in electrostimulation of a body tissue are disclosed. A system may receive image data of at least a portion of the lead including image data of a marker configured to identify a rotational orientation of the lead. The system may receive at least one template of the lead having a specified rotational orientation. Each template may include a reference data cube and a reference marker direction vector. The system may generate a target data cube of the marker using the image data of the marker, and register the reference data cube to the target data cube to produce a transformation operator. The system may estimate the rotational orientation of the lead using the reference marker direction vector and the determined transformation operator.

Claims

1. A system for determining a rotational orientation of a lead for use in electrostimulation of a body tissue, wherein the lead has a longitudinal axis and a marker configured to identify a rotational orientation about the longitudinal axis of the lead, the system comprising:

a data input circuit configured to receive computed tomography (CT) image data of at least a portion of the lead including CT image data of the marker;

a template receiver circuit configured to receive at least one template of the lead having a specified rotational orientation, the at least one template including (1) a reference data cube (X_R) of the marker and (2) a reference marker direction vector (ν

_R) indicative of the specified rotational orientation of the lead;

a lead orientation estimator circuit, including;

a marker recognition circuit configured to produce a target data cube (X_T) of the marker using the CT image data of the marker;

a data registration circuit configured to register the reference data cube (X_R) to the target data cube (X_T) to produce a transformation operator (Φ

) for transforming X_R into a transformed reference data cube Φ

(X_R) that matches X_T within a specified margin; and

an estimator circuit configured to estimate the rotational orientation of the lead using the reference marker direction vector (ν

_R) and the determined transformation operator (Φ

);

an output unit, configured to produce a graphical representation of the lead and the estimated rotational orientation of the lead.

2. The system of claim 1, wherein the marker recognition circuit is configured to identify the marker using an anisotropic shape of the CT image data of the marker, and produce the target data cube (X_T) of the marker using the CT image data of the identified marker.

3. The system of claim 2, wherein the marker includes a first portion and a second portion, the first portion including a radiopaque band around a circumference of the lead, the radiopaque band having an anisotropic shape of a bulge in the CT image data, and the second portion defining a radiolucent window having an anisotropic shape of a dimple in the CT image data.

4. The system of claim 1, further comprising a template formation circuit, coupled to the data input circuit, configured to generate a template of the lead, wherein:

the data input circuit is configured to receive CT image data of the lead obtained when the lead is substantially aligned with an imaging axis, the CT image data including CT image data of the marker; and

the template formation circuit is configured to;

identify a lead tip and a lead shaft using the CT image data;

detect a lead axis using the identified lead tip and lead shaft;

identify the marker using the CT image data of the marker;

produce the reference data cube (X_R) of the template using the CT image data of the marker and the detected lead axis; and

determine the reference direction vector (ν

_R) of the template using the reference data cube.

5. The system of claim 4, wherein the template formation circuit is configured to determine the reference direction vector, including:

detect a midpoint of the marker using the identified lead tip and the lead shaft;

detect a bulging point within the identified marker, the bulging point being spatially farther away from the midpoint of the marker than other points within the identified marker;

generate an initial marker direction vector that originates at the midpoint of the marker and points to the bulging point; and

determine the reference direction vector (ν

_R) as a projection of the initial marker direction vector onto a plane perpendicular to the detected lead axis.

6. The system of claim 4, wherein the template formation circuit is configured to determine the reference direction vector, including:

identify a symmetric plane through the detected lead axis around which the CT image data of the marker is substantially reflective symmetric;

produce two candidate marker direction vectors along the symmetric plane, the two candidate marker direction vectors originating from and perpendicular to the lead axis, and pointing to two opposite directions; and

determine the reference direction vector (ν

_R) as one of the two candidate marker direction vectors that is spatially closer to a bulging point within the identified marker than the other of the two candidate marker direction vectors.

7. The system of claim 1, wherein the lead orientation estimator circuit is configured to estimate the rotational orientation of the lead by applying the determined transformation operator (Φ

) to the reference direction vector (ν

_R) to produce an estimated marker direction vector ({tilde over (ν

)}_T) indicative of the rotational orientation of the lead relative to an imaging axis used for producing the CT image data of the at least a portion of the lead.

8. The system of claim 1, wherein:

the template receiver circuit is configured to receive two or more templates of the lead; and

the data registration circuit is configured to perform a multi-atlas registration of respective reference data cubes associated with the two or more templates to the target data cube.

9. The system of claim 8, wherein the estimator circuit is configured to:

produce two or more estimated marker direction vectors of the lead by applying the respective transformation operators to the reference direction vector (ν

_R); and

determine the rotational orientation of the lead using a combination of the two or more estimated marker direction vectors.

10. The system of claim 9, wherein the estimator circuit is configured to produce a confidence indicator of the estimated rotational orientation of the lead using the two or more estimated marker direction vectors.

11. The system of claim 10, further comprising an electrostimulator circuit configured to generate directional electrostimulation for modulating the body tissue using the lead oriented at least according to the estimated rotational orientation.

12. A system for determining a rotational orientation of a lead for use in electrostimulation of a body tissue, wherein the lead has a longitudinal lead axis and a marker configured to identify a rotational orientation about the longitudinal axis of the lead, the system comprising:

a data input circuit configured to receive image data of at least a portion of the lead including image data of the marker;

a template receiver circuit configured to receive at least one template of the lead having a specified rotational orientation, the at least one template including (1) a reference data cube (X_R) of the marker and (2) a reference marker direction vector (ν

_R) indicative of the specified rotational orientation of the lead;

a lead orientation estimator circuit, including;

a marker recognition circuit configured to produce a target data cube (X_T) of the marker using the image data of the marker;

a data registration circuit configured to register the reference data cube (X_R) to the target data cube (X_T) to produce a transformation operator (Φ

) for transforming X_R into a transformed reference data cube Φ

(X_R) that matches X_T within a specified margin, wherein the transformation operator (Φ

) includes at least one non-rigid transformation to reduce local geometric discrepancies by aligning the reference data cube (X_R) with the target data cube (X_T); and

an estimator circuit configured to estimate the rotational orientation of the lead using the reference marker direction vector (ν

_R) and the determined transformation operator (Φ

);

an output unit, configured to produce a graphical representation of the lead and the estimated rotational orientation of the lead.

13. The system of claim 12, wherein the data input circuit is configured to receive the image data including data of a computed tomography (CT) scan of the marker.

14. A method for determining a rotational orientation of a lead for use in electrostimulation of a body tissue, wherein the lead has a longitudinal axis and a marker configured to identify a rotational orientation about the longitudinal axis of the lead, the method comprising:

receiving computed tomography (CT) image data of at least a portion of the lead including CT image data of the marker;

receiving at least one template of the lead having a specified rotational orientation, the at least one template including (1) a reference data cube (X_R) of the marker and (2) a reference marker direction vector (ν

_R) indicative of the specified rotational orientation of the lead about the longitudinal axis;

producing a target data cube (X_T) of the marker using the CT image data of the marker;

registering the reference data cube (X_R) to the target data cube (X_T) to produce a transformation operator (Φ

) for transforming X_R into a transformed reference data cube Φ

(X_R) that matches X_T within a specified margin; and

estimating the rotational orientation of the lead using the reference marker direction vector (ν

_R) and the determined transformation operator (Φ

).

15. The method of claim 14, wherein receiving the CT image data includes receiving CT image data of a computed tomography (CT) scan of the marker.

16. The method of claim 14, further comprising creating a template of the lead, including:

receiving CT image data of the lead obtained when the lead is substantially aligned with an imaging axis, the CT image data of the lead including CT image data of the marker;

identifying a lead tip and a lead shaft using the CT image data;

detecting a lead axis using the identified lead tip and lead shaft;

identifying the marker using the CT image data;

producing a reference data cube (X_R) of the template using the CT image data of the marker and the detected lead axis; and

determining a reference direction vector (ν

_R) of the template using the reference data cube.

17. The method of claim 16, wherein determining the reference direction vector includes:

detecting a midpoint of the marker using the identified lead tip and the lead shaft;

detecting a bulging point within the identified marker, the bulging point being spatially farther away from the midpoint of the marker than other points within the identified marker;

generating an initial marker direction vector that originates at the midpoint of the marker and points to the bulging point; and

determining the reference direction vector (ν

_R) as a projection of the initial marker direction vector onto a plane perpendicular to the detected lead axis.

18. The method of claim 16, wherein determining the reference direction vector includes:

identifying a symmetric plane through the detected lead axis around which the CT image data of the marker is substantially reflective symmetric;

producing two candidate marker direction vectors along the symmetric plane, the two candidate marker direction vectors originating from and perpendicular to the lead axis, and pointing to two opposite directions; and

determining the reference direction vector (ν

_R) as one of the two candidate marker direction vectors that is spatially closer to a bulging point within the identified marker than the other of the two candidate marker direction vectors.

19. The method of claim 14, wherein estimating the rotational orientation of the lead includes applying the determined transformation operator (Φ

) to the reference direction vector (ν

_R) to produce an estimated marker direction vector ({tilde over (ν

)}_T) indicative of the rotational orientation of the lead relative to an imaging axis used for producing the CT image data of the at least a portion of the lead.

20. The method of claim 14, wherein:

registering the reference data cube (X_R) to the target data cube (X_T) includes performing a multi-atlas registration of respective reference data cubes associated with two or more of the templates to the target data cube, to produce respective transformation operators corresponding to the two or more of the templates; and

estimating the rotational orientation of the lead includes estimating the rotational orientation using a combination of the two or more estimated marker direction vectors estimated using reference direction vectors and respective transformation operators.