Image-guided therapy of a tissue

1. A head fixation apparatus comprising:

a plurality of support posts for supporting a head of a patient;

a curved ring portion including a lower ring portion, the curved ring portion comprising a plurality of connectors configured to adjustably and releasably mount the plurality of support posts on the lower ring portion, such that the plurality of support posts are selectively mounted to a subset of the plurality of connectors in a customized arrangement for the patient;

a ring mount configured for fixation to a platform, wherein the ring mount comprises a curved channel substantially matching a curvature of the curved ring portion; and

a mount locking mechanism for locking the curved ring portion mounted within the channel of the ring mount;

wherein,

the curved ring portion is configured to rotate within the channel of the ring mount while the ring mount is fixed to the platform, an angular head position of the patient being selectably adjustable while the patient is laying on the platform, and

the mount locking mechanism is configured to lockably engage the curved ring portion within the channel of the ring mount upon positioning of the angular head position of the patient.

2. The head fixation apparatus of claim 1 , wherein the curved ring portion and the ring mount channel are semicircular.

3. The head fixation apparatus of claim 1 wherein the curved ring portion further comprises an upper ring portion including an upper locking mechanism, and

wherein the curved ring portion comprises a lower locking mechanism configured to mate with the upper locking mechanism such that the upper ring portion and the lower ring portion are adapted to encircle the head of the patient.

4. The head fixation apparatus of claim 3 , wherein the upper ring portion comprises a nose indent in which a nose of the patient aligns when the head of the patient is positioned in the head fixation apparatus.

5. The head fixation apparatus of claim 3 , wherein the lower locking mechanism is configured to engage with the upper locking mechanism at two or more mating positions to form a head fixation ring, and

wherein an interior area of the head fixation ring is adjustable.

6. The head fixation apparatus of claim 5 , wherein one of the upper locking mechanism and the lower locking mechanism comprises a plurality of openings, and the other of the upper locking mechanism and the lower locking mechanism comprises a set screw.

7. The head fixation apparatus of claim 5 , wherein one of the upper locking mechanism and the lower locking mechanism comprises a plurality of indents, and the other of the upper locking mechanism and the lower locking mechanism comprises a spring-loaded plunger.

8. The head fixation apparatus of claim 3 , further comprising:

at least one additional upper ring portion, wherein one of the upper ring portion and the additional upper ring portion is selected based on a size of the head of the patient.

9. The head fixation system of claim 3 , wherein the upper ring portion comprises a plurality of upper support posts, wherein each of the plurality of upper support posts comprises a respective fixation mechanism configured to fix a position of the head of the patient.

10. The head fixation apparatus of claim 1 , wherein each of the plurality of support posts includes at least one connection point that releasably connects to a respective fixation mechanism that fixes a position of the head of the patient.

11. The head fixation apparatus of claim 10 , wherein the respective fixation mechanism is one of a conforming abutment and a fixation pin.

12. The head fixation apparatus of claim 10 , wherein each of the plurality of support posts includes a plurality of connection points, and

wherein positioning of the respective fixation mechanism upon the respective support post is adjustable.

13. The head fixation apparatus of claim 12 , wherein the plurality of connection points are positioned upon each of the plurality of support posts in an arrangement providing at least one of a plurality of linear connection options and a plurality of radial connection options for connecting the respective fixation mechanism to the respective support post.

14. The head fixation apparatus of claim 1 , wherein the mount locking mechanism comprises a clamp, and

wherein the angular head position is continuously adjustable by rotating the curved ring portion within the channel to a desired angular head position.

15. The head fixation apparatus of claim 1 , wherein the curved ring portion comprises a plurality of mating features for mating with the mount locking mechanism.

16. A head fixation system for immobilizing a head of a patient, comprising:

a plurality of support posts, wherein each of the plurality of support posts includes a plurality of connection points for releasable connection of a respective fixation mechanism to fix a position of the head of the patient, such that positioning of the respective fixation mechanism upon the respective support post is adjustable; and

a curved ring portion including a lower ring portion, the curved ring portion comprising a plurality of connectors configured to adjustably and releasably mount the plurality of support posts on the lower ring portion, such that the plurality of support posts are selectively mounted to a subset of the plurality of connectors in a customized arrangement for a patient,

wherein the plurality of support posts are selectively positioned in a plurality of support post mounting slots arranged radially along the lower ring portion, to support the head of the patient.

17. The head fixation system of claim 16 , further comprising:

a ring mount configured for fixation to a platform, wherein the ring mount comprises a curved channel substantially matching a curvature of the curved ring portion; and

a mount locking mechanism for locking the curved ring portion within the channel of the ring mount,

wherein the curved ring portion is configured to rotate within the channel of the ring mount while the ring mount is fixed to the platform, an angular head position of the patient being selectably adjustable while the patient is laying on the platform, and

wherein the mount locking mechanism is configured to lockably engage the curved ring portion within the channel of the ring mount upon positioning of the angular head position of the patient.

18. The head fixation system of claim 17 , wherein the curved ring portion includes an upper ring portion configured to releasably mate with the lower ring portion to encircle the head of the patient, and

wherein at least one of the lower ring portion and the upper ring portion comprises at least one fiducial marker, such that, upon positioning the angular head position of the patient and lockably engaging the curved ring portion with the mount locking mechanism, the at least one fiducial marker identifies the angular head position within the channel of the ring mount.

19. The head fixation system of claim 18 , further comprising:

a memory having instructions stored thereon, wherein the instructions, when executed, cause a processor to:

identify, within one or more images, the at least one fiducial marker, and calculate, based upon a position of the at least one fiducial marker, an angle of rotation of the head fixation system.

20. The head fixation system of claim 19 , wherein the one or more images comprise magnetic resonance (MR) images.

21. The head fixation system of claim 19 , wherein the instructions, when executed, cause the processor to present a model on a graphical user interface, based upon the calculated angle of rotation of a patient positioning relative to a neurosurgical apparatus.