Marker system and related stereotactic procedure

Claims

What is claimed is:

1. A medical method comprising the steps, not necessarily in order, of:

positioning a patient for a first medical procedure;

attaching a mechanically free locator to the patient, the locator having at least 3 fiducial markers thereon and being in registry with a portion of the patient;

using the fiducial markers a first time to get precise positioning information relative to at least part of the patient;

performing a first medical procedure on the patient;

after the first medical procedure, removing the locator from the patient;

at a later time after the removing of the locator, re-attaching the locator to the patient, the locator again being in registry with the portion of the patient and having an identical orientation relative to the portion of the patient as when the locator was previously attached;

after the re-attaching step, using the fiducial markers a second time to get precise positioning information relative to the at least part of the patient;

after the re-attaching step, performing a second medical procedure on the patient; and wherein

before performing the second medical procedure, the patient is positioned using a positioner independent of the locator to adjust and secure at least the portion of the patient in a desired position.

2. The medical method of claim 1 wherein the attaching and re-attaching of the locator is non-invasive.

3. The medical method of claim 1, wherein the using of the fiducial markers the first and second times utilizes a sensing subsystem for sensing the positions of the fiducial markers.

4. A system for medical procedures, the system comprising:

a locator attachable to a patient, having at least 3 LEDs thereon, and having a registration portion for registration with a portion of a patient's body, the registration portion allowing removal of the locator from the patient and re-attachment to the patient with an identical orientation relative to the portion of the patient as when the locator was previously attached, the locator being mechanically free such that a patient is positionable without applying forces to the locator during patient positioning; a positioner independent of the locator and operable to adjust and to secure at least the portion of the patient in a desired position; and

a sensing subsystem for sensing the positions of the LEDs when the patient is in the desired position.

5. The system of claim 4 wherein the locator is non-invasive.

6. The system of claim 4 further comprising an imaging subsystem for imaging the patient.

7. A medical method comprising the steps, not necessarily in order, of:

positioning a patient for a first medical procedure;

attaching a locator to a patient, the locator having at least 3 fiducial markers thereon and being in registry with a portion of the patient, the locator being mechanically free such that a patient is positionable without applying forces to the locator during patient positioning;

using fiducial markers a first time to get precise positioning information relative to at least part of the patient;

performing a first medical procedure on the patient;

after the first medical procedure, removing the locator from the patient;

at a later time after the removing, reattaching the locator to the patient, the locator again being in registry with the portion of the patient and having an identical orientation relative to the portion of the patient as when the locator was previously attached;

after the re-attaching step, using fiducial markers a second time to get precise positioning information relative to the at least part of the patient; and

after the re-attaching step, performing a second medical procedure on the patient; and

wherein the locator is a bite plate with an external portion connected thereto, and the fiducial markers are on the external portion, and wherein the attaching includes using a mold of dental impression material to bring the bite plate in registry with teeth of the patient, and wherein the re-attaching uses the mold to bring the bite plate in registry with teeth of the patient with an identical orientation relative to the teeth as when the bite plate was previously attached; and

wherein the second medical procedure is a remedial procedure treating at least one problem precisely localized in the first medical procedure; and

wherein, before performing the second medical procedure, the patient is positioned using a positioner independent of the locator to adjust patient position and to secure at least the portion of the patient in a desired position.

8. The medical method of claim 7 wherein the first medical procedure is an imaging of at least a portion of the patient.

9. The medical method of claim 7 wherein the second medical procedure includes radiotherapy.

10. The medical method of claim 7 wherein both the first and second medical procedures include radiotherapy.

11. A system for medical procedures, the system comprising:

a locator attachable to a patient, having at least 3 fiducial markers thereon, and having a registration portion for registration with a portion of a patient's body, the registration portion allowing removal of the locator from the patient and re-attachment to the patient with an identical orientation relative to the portion of the patient as when the locator was previously attached, the locator being mechanically free such that a patient is positionable without applying forces to the locator during patient positioning;

a positioner independent of the locator and operable to adjust and to secure at least the portion of the patient in a desired position; and

wherein the locator is a bite plate with an external portion connected thereto, and the fiducial markers are on the external portion, and the bite plate has a mold to bring the bite plate in registry with teeth of the patient with an identical orientation relative to the teeth as when the bite plate was previously attached.

12. The system of claim 11 further comprising a radiotherapy apparatus for applying radiation treatment to a patient, the positioner and sensing subsystem allowing proper positioning of the patient for applying radiation treatment.

13. A system for medical procedures, the system comprising:

a locator attachable to a patient, having at least 3 fiducial markers thereon;

a medical device means for performing a diagnostic imaging or a therapeutic medical procedure on a patient;

a sensing subsystem for sensing the positions of the fiducial markers when the patient is in a position for performing the medical procedure using the medical device;

a first comparison means for comparing positioning information of the fiducial markers to positioning information indicative of a position of the medical devices, and for supplying information indicative of an actual offset between the position of the fiducial markers and the position of the medical device; and

a second comparison means for comparing the actual offset information with desired offset information and for generating an error signal based thereon.

14. The system of claim 13 wherein the locator has a registration portion for registration with a portion of a patient's body, the registration portion allowing removal of the locator from the patient and re-attachment to the patient with an identical orientation relative to the portion of the patient as when the locator was previously attached, the locator being mechanically free such that a patient is positionable without applying forces to the locator during patient positioning; and wherein the locator is a bite plate with an external portion connected thereto, and the fiducial markers are on the external portion, and the bite plate has a mold to bring the bite plate in registry with teeth of the patient, and the mold is operable to bring the bite plate in registry with teeth of the patient with an identical orientation relative to the teeth as when the bite plate was previously attached.

15. The system of claim 13 wherein the locator is selected from the group consisting of: a head ring secured to a support and a head holder secured to a support.

16. The system of claim 13 wherein the locator is a head ring and has a member secured thereto, and wherein the three fiducial markers are mounted to the member so as to uniquely define a plane.

17. A method for performing a diagnostic imaging or a therapeutic medical procedure comprising the steps of, not necessarily in order:

attaching a mechanically free locator to a patient, the locator having at least 3 fiducial markers thereon;

placing the patient adjacent a medical device operable for performing said diagnostic imaging or therapeutic medical procedure on a patient;

sensing the positions of the fiducial markers when the patient is in a position for performing the diagnostic imaging or therapeutic medical procedure using the medical device; and

generating error signals indicating differences between actual patient position information relative to the medical device and a desired patient position relative to the medical device.

18. The method of claim 17 further including the step of adjusting the relative positioning of the patient and the medical device to null or minimize the error signals.

19. The method of claim 17, further including the step of:

performing a first medical procedure on the patient.

20. The method of claim 19, further including the steps of:

removing the locator from the patient after performing said first medical procedure;

later reattaching the locator to the patient at an identical position and orientation relative to the patient;

again sensing the fiducial markers and generating error signals dependent on differences between actual patient position information relative to the medical device and a desired patient position relative to the medical device; and

performing a second medical procedure on the patient.