Method of control and of positioning with the aid of laser systems, and device for implementing said method

1. A method for adjusting laser beams ( 4 ) for scanners arranged on a support, notably dedicated to radiotherapy, which is positioned on said support, by means of a device which consists of a single one-piece assembly ( 1 ) comprising a certain number of distinct parts, and assembled in a non-dismantleable manner, which includes both a certain number of position sensors ( 3 ), and an electronic control board ( 8 ) suited to the one-piece structure of said assembly ( 1 ), said sensors ( 3 ) making it possible to visualize the exact position of said beams ( 4 ), so as to accurately adjust them automatically by motor-driven systems, wherein it comprises the following steps:

installing the apparatus ( 1 ) on the table of the scanner;

presetting the position using the three supporting feet ( 6 ) and the embedded spirit levels ( 7 );

moving the table of the scanner to position the front face ( 11 ) of the apparatus in the plane of the isocenter of the scanner, and a positioning using the internal lasers of the scanner;

acquisition of images, wherein the images obtained make it possible to check the correct position of the apparatus ( 1 ) by using at least 4 centering balls ( 5 ) present on the front face ( 11 );

finalizing the position of the apparatus;

once the position is validated, moving the table of the scanner by the nominal distance between the machine isocenter and the laser isocenter, wherein this distance is set, which is determined and validated at the time of installation of the lasers;

connecting the apparatus ( 1 ) to a PC tablet controlling the positions of the laser beam ( 4 );

powering the apparatus ( 1 ) up,

powering the lasers beams ( 4 ) up and re-setting the positions to zero;

starting up the laser beam ( 4 ) search sequence by multiplexing, wherein the position of each laser beam ( 4 ) is then determined using the embedded cells ( 3 ) in the apparatus ( 1 );

doing the acquisition of the values and transfer to the tablet PC of the adjustment phase of each laser beam ( 4 ).

2. A method according to any preceding claim, wherein said process of use comprises each of said steps being carried out in the specified order.

3. A device for adjusting laser beams ( 4 ) for scanners arranged on a support, notably dedicated to radiotherapy, which is positioned on said support, in particular for implementing the method as defined in claim 1 , wherein it consists of a single one-piece assembly ( 1 ) comprising a certain number of distinct parts, and assembled in a non-dismantleable manner, in that it includes both a certain number of position sensors ( 3 ), and an electronic control board ( 8 ) suited to the one-piece structure of said assembly ( 1 ), said sensors ( 3 ) being arranged to visualize the exact position of said beams ( 4 ), so as to accurately adjust them automatically by motor-driven systems; the device being equipped on its base ( 9 ) with three adjustable feet ( 6 ) allowing for an azimuth adjustment of said assembly ( 1 ) on the table of the scanner, the latter comprising spirit levels ( 7 ) which are positioned on the base plate ( 9 ) to assist in the positioning by operators and a certain number of centering balls ( 5 ) present on the front face ( 11 ).

4. A device according to any preceding claim, wherein it comprises two laser elements ( 13 , 14 ) generating a beam with a different color which is selectable, particularly red or green, up to the choice of the operator.

5. A device according to any preceding claim, wherein said color of the laser beam is instantly interchangeable.

6. A device according to claim 3 , wherein said single block set ( 1 ) comprises seven distinct parts, and wherein at least ten, more particularly twelve position sensors ( 3 ) are provided.

7. A device according to claim 3 , wherein it is a portable apparatus ( 1 ).

8. A device according to claim 3 , wherein it incorporates two standard industrial laser elements.

9. A device according to claim 3 , wherein it includes dedicated software suited to the constraints of use in a hospital environment.

10. A device according to any preceding claim, wherein it comprises integrated measurement cells ( 3 ), with dimension calculated for better accuracy, being dedicated to an automatic adjustment of the system for allowing an accurate measurement of the position of each said beam ( 4 ), and adjustment of each beam relative to one another, as well as an adjustment in closed loop mode using said software.

11. A device according to claim 5 , wherein it has a guaranteed positioning result, with a final accuracy of at least 0.1 mm.

12. A device for adjusting laser beams for scanners on a support dedicated to radiotherapy, in particular according to claim 3 , wherein it has at least one mechanized optical head ( 12 ) with calibrated mechanical precision elements for ensuring the necessary degrees of freedom.

13. A device according to any preceding claim, wherein it comprises filtering means of the external vibratory disturbances.

14. A device according to claim 12 , wherein it comprises guiding means, particularly a rail for the movements of said optical heads ( 12 ) with precision mechanical rolling bearings incorporating a measurement of the position of the optical head ( 12 ) on its rail.

15. A device according to claim 12 , wherein it comprises a mechanical assembly with lever arm, made up of two precision stepper motors ( 15 , 16 ) equipped with end-of-travel sensors, two laser modules ( 13 , 14 ) and an electronic control board, which allows for being driven by a radio link, for receiving the information from the central CPU and for controlling the two said stepper motors ( 15 , 16 ).

16. A device according to claim 3 , wherein it comprises controlling means for the verification of the exact position of the laser beams ( 4 ) according to the setpoints to be given or to provide by the operator.

17. Use of software for carrying out at least part of the steps, respectively, stage of the method according to claim 1 , notably by means of a device for adjusting laser beams ( 4 ) for scanners arranged on a support, notably dedicated to radiotherapy, which is positioned on said support, in particular for implementing the method as defined in claim 1 , wherein it consists of a single one-piece assembly ( 1 ) comprising a certain number of distinct parts, and assembled in a non-dismantleable manner, in that it includes both a certain number of position sensors ( 3 ), and an electronic control board ( 8 ) suited to the one-piece structure of said assembly ( 1 ), said sensors ( 3 ) being arranged to visualize the exact position of said beams ( 4 ), so as to accurately adjust them automatically by motor-driven systems; the device being equipped on its base ( 9 ) with three adjustable feet ( 6 ) allowing for an azimuth adjustment of said assembly ( 1 ) on the table of the scanner, the latter comprising spirit levels ( 7 ) which are positioned on the base plate ( 9 ) to assist in the positioning by operators and a certain number of centering balls ( 5 ) present on the front face ( 11 ), wherein it has modules forming the functionalities of the software used wholly or partly, possibly in a different order, which are listed herein below:

a) Parameterization of the software allowing managing all the software data operating parameters;

b) User management allowing managing the creation, the updating, the deletion and printing of data specific to the program users, wherein each user is provided with a program access level;

c) System logging, wherein the use of each of the functionalities and all the alarms detected are the subject of a record in a log;

d) Online help, wherein the software is provided with a context-sensitive “User Guide”, which can be viewed at any time on the screen of the tablet PC or on the desktop PC and which details all the functionalities of the software;

e) Alarm management, wherein in the event of a malfunction of one or other of the components of the system and detected by the software, the latter switches to “System fault mode”, wherein a pop-up list of the faults listed is displayed on the screen and, wherein alongside each fault, setpoints guide the user in what to do;

f) Backup/restore operating data, allowing to backup automatically, or at the request, all of the program database;

g) Patient and session management allowing creating manually by input a number of patients, a number of fields notably tumors for each of these patients, a number of positioning points for each of these fields, and automatically creating the patients, fields and positioning points from data imported from the text-format TPS files;

h) TPS data recovery, wherein each time the patient passes through the scanner, the operator proceeds with outlining the tumor by dots, wherein a file is thus generated by the TPS console computer system, wherein the software recovers the above data and incorporates them in its own database;

i) Display/print operating data, wherein all the information concerning the operating data can be displayed on the screen;

j) Equipment management, wherein the software allows controlling the creation, the updating and the printing of all the configuration data of the equipment that make up the system of the invention on each operating site;

k) Equipment self-test, wherein on starting up the software and after authentication of the user, a self-test is carried out by the program to check the integrity of the system, wherein said self-test can also be launched at the request of the user;

l) Selection of the laser beam colors, wherein the software allows selecting, at any time and in any of the modules of the program, the color (green, red or none) of each of the laser beams, individually or for all of the beams;

m) Manual equipment calibration, wherein the manual calibration of each of the laser beams (motor-driven HITs and moving HITs) allows adjusting and calibrating the system during its installation, and do so in light of the physical characteristics of the installation site;

n) Automatic equipment calibration, wherein the automatic calibration of each of the laser beams—motor-driven HITs and moving HITs—is carried out with the use of the above-mentioned so-called smart phantom equipment, wherein it is a smart system provided with sensors or photoreceivers which record the position of each of the beams in service, wherein said system is interrogated by the software which, given the information collected, automatically drives the laser beams according to the desired orientations by coincidence of the laser beams, and to the positions sought in Isocenter, wherein the software keeps a historical log recording all the modifications made on calibrating any of the laser beams;

o) calibration of the axes, wherein the software includes the calibration functionality for each of the laser beams—motor-driven HITs and moving HITs—operated in the system, wherein this calibration allows obtaining an accuracy of up to 0.1 mm of linear movement of each of the laser beams on the skin of the patient, wherein a calibrator or moving sensor is used to calibrate the axes;

p) Laser beams initialization, wherein the software carries out a laser initialization sequence in the following cases: when the program is started up once the self-test has been successfully carried out and/or at the request of the user, wherein said initialization sequence performs the operations of positioning each of the laser heads at the origin of the axes, respectively, positioning of each laser head in light of the calibration data, wherein the user is informed of the correct execution of the laser beams initialization sequence;

q) TPS setpoints, wherein the software is able to position the laser beams in light of setpoints linked to positioning points selected by the user, wherein these positioning points correspond to the target points derived from the TPS data, wherein the laser beams are positioned at the laser isocenter, or already having been the object of a TPS setpoint, these beams are moved in light of the coordinates indicated by these positioning points;

r) patient placement allowing individually moving the so-called “sagittal” laser beam to the left or to the right of the patient for a specific marking on the skin, wherein the value of the movement of the laser beam is entered by the operator; and

s) display/print equipment data.

18. Use according to any preceding claim, wherein the process of use comprises each of the steps carried out according to said software, particularly in the specified order.

19. Use according to claim 17 , wherein the output of all or part of this information on a printer can be requested by the user.