Optical surface tracking camera placement for radiotherapy

1 . A radiotherapy device comprising:

a rotatable gantry comprising a front, a rear and a bore, and a radiotherapy treatment device configured to deliver a therapeutic dose of radiation therapy to a subject positioned within the bore;

a support surface moveable into the bore from a side of the radiotherapy device corresponding to the front of the rotatable gantry;

a plurality of cameras for monitoring a subject that is located on the support surface, the plurality of cameras including a rear camera disposed outside of the bore and adjacent to the rear of the rotatable gantry, wherein the rear camera is a time of flight camera;

one or more near-bore cameras disposed on or adjacent to the front of the rotatable gantry or disposed on or adjacent to an interior of the bore proximal to the front of the rotatable gantry, wherein the rear camera and the one or more near-bore cameras have at least partially overlapping views and are arranged to view the subject in a treatment position in which most or all of the support surface is inside of the bore; and

a controller configured to determine an average of distance measurements to a surface of the subject over a plurality of pixels of the rear camera, wherein the controller is further configured to use the determined average of distance measurements and location data from the one or more near-bore cameras to verify that the subject is positioned for accurate delivery of radiotherapy treatment to one or more target regions within the subject and to control the radiotherapy treatment device to deliver the therapeutic dose of radiation therapy to the subject positioned within the bore as verified.

2 . The radiotherapy device according to claim 1 , wherein the rear camera is disposed at a vertical height above a vertical height of the support surface, and/or wherein the rear camera is disposed at a vertical height above the vertical height of a central axis of the bore.

3 . The radiotherapy device according to claim 1 , wherein the one or more near-bore cameras are disposed at a vertical height above a vertical height of the support surface and below a vertical height of a top of the radiotherapy device.

4 . The radiotherapy device according to claim 1 , wherein the one or more near-bore cameras comprise a first near-bore camera disposed towards a left edge of the bore relative to a central axis of the bore, and a second near-bore camera disposed towards a right edge of the bore relative to the central axis of the bore.

5 . The radiotherapy device according to claim 1 , wherein the plurality of cameras comprise one or more setup cameras disposed outside the bore and located on a side of the radiotherapy device corresponding to the front of the rotatable gantry.

6 . The radiotherapy device according to claim 5 , wherein the one or more setup cameras are disposed at a vertical height above a vertical height of a top of the bore.

7 . The radiotherapy device according to claim 5 , wherein the one or more setup cameras comprise a first setup camera disposed left of the bore relative to a central axis of the bore, and a second setup camera disposed right of the bore relative to the central axis of the bore.

8 . The radiotherapy device according to claim 5 , wherein at least the one or more setup cameras are arranged to view the subject in a setup position in which most or all of the support surface is outside of the bore.

9 . The radiotherapy device according to claim 1 , wherein multiple of the plurality of cameras are time of flight cameras.

10 . The radiotherapy device of claim 1 , where the controller is configured to determine an average of distance measurements to the surface of the subject over a plurality of pixels of the one or more near-bore cameras, wherein the controller is further configured to use the determined average of distance measurements from both the rear camera and the one or more near-bore cameras to verify that the subject is positioned for accurate delivery of radiotherapy treatment to one or more target regions within the subject.

11 . A method for imaging a subject using a radiotherapy device comprising a rotatable gantry including a radiotherapy treatment device configured to deliver a therapeutic dose of radiation therapy to a subject positioned within a bore, a support surface, a controller, and a plurality of cameras, the method comprising:

moving the support surface with the subject disposed thereon into the bore of the rotatable gantry from a side of the radiotherapy device corresponding to a front of the rotatable gantry;

obtaining one or more images of the subject using a rear camera of the plurality of cameras, the rear camera being disposed outside of the bore and adjacent to a rear of the rotatable gantry, wherein the rear camera is a time of flight camera;

obtaining one or more images of the subject using one or more near-bore cameras of the plurality of cameras, wherein the one or more near-bore cameras are disposed on or adjacent to the front of the rotatable gantry or disposed on or adjacent to an interior of the bore proximal to the front of the rotatable gantry, wherein the rear camera and the one or more near-bore cameras have at least partially overlapping views and are arranged to view the subject in a treatment position in which most or all of the support surface is inside of the bore;

determining, using the controller, an average of distance measurements to a surface of the subject over a plurality of pixels of the rear camera; and

using the determined average of distance measurements and location data from the one or more near-bore cameras, verifying that the subject is positioned for accurate delivery of radiotherapy treatment to one or more target regions within the subject and controlling radiation treatment device to deliver the therapeutic dose of radiation therapy to the subject positioned within the bore as verified.

12 . The method according to claim 11 , further comprising:

with the subject disposed on the support surface and before moving the support surface into the bore, obtaining one or more further images of the subject using one or more cameras of the plurality of cameras.

13 . The method according to claim 11 , wherein the rear camera is disposed at a vertical height above a vertical height of the support surface, and/or wherein the rear camera is disposed at a vertical height above a vertical height of a central axis of the bore.

14 . The method according to claim 11 , wherein the one or more near-bore cameras are disposed at a vertical height above a vertical height of the support surface and below a vertical height of a top of the radiotherapy device, and wherein the one or more near-bore cameras comprise a first near-bore camera disposed towards a left edge of the bore relative to a central axis of the bore, and a second near-bore camera disposed towards a right edge of the bore relative to the central axis of the bore.

15 . The method according to claim 14 , wherein at least the rear camera and the one or more near-bore cameras view the subject in a treatment position in which most or all of the support surface is inside of the bore.

16 . The method according to claim 11 , wherein the plurality of cameras comprises one or more setup cameras disposed outside the bore and located on the side of the radiotherapy device corresponding to the front of the rotatable gantry, wherein the one or more setup cameras are disposed at a vertical height above a vertical height of a top of the bore, and wherein the one or more setup cameras comprise a first setup camera disposed left of the bore relative to a central axis of the bore, and a second setup camera disposed right of the bore relative to the central axis of the bore.

17 . The method according to claim 16 , wherein at least the one or more setup cameras view the subject in a setup position in which most or all of the support surface is outside of the bore.

18 . The method according to claim 11 , wherein multiple of the plurality of cameras are time of flight cameras.

19 . The method of claim 11 , further comprising determining an average of distance measurements to the surface of the subject over a plurality of pixels of the one or more near-bore cameras, and verifying that the subject is positioned for accurate delivery of radiotherapy treatment to one or more target regions within the subject further using the determined averages of distance measurements from both the rear camera and the one or more near-bore cameras.