SYSTEMS AND METHODS FOR ADAPTIVELY CONTROLLING FILAMENT CURRENT IN AN X-RAY TUBE

1 . (canceled)

2 . A method of controlling an x-ray tube of an imaging system comprising:

receiving, at the imaging system, calibration data for the x-ray tube, the calibration data including a filament current value for a plurality of exposure values based on different tube current and tube voltage combinations;

storing the calibration data at the imaging system;

based on the stored calibration data, controlling the x-ray tube, via a high voltage control circuit of the imaging system operationally coupled to the x-ray tube, to emit a plurality of sequence exposures;

measuring a resistance value, via the high voltage control circuit, of a filament of the x-ray tube after a predetermined number of sequence exposures of the plurality of sequence exposures;

storing each measured resistance value at the imaging system;

determining, at the imaging system, a change in the stored measured resistance values of the filament, wherein the determined changed resistance value is based on a difference between the stored measured resistance values over a number count of the emitted plurality of sequence exposures; and

adjusting the filament current value within the calibration data stored at the imaging system for at least one of the plurality of exposure values based on the determined changed resistance value.

3 . The method of claim 2 , wherein measuring the resistance value includes applying, via the high voltage control circuit, a constant filament current value to the filament after each of the predetermined number of sequence exposures.

4 . The method of claim 3 , further comprising waiting a predetermined time between an end of a sequence exposure and the application of the constant filament current value.

5 . The method of claim 3 , wherein the application of the constant filament current value is performed when the filament has cooled after a sequence exposure.

6 . The method of claim 2 , wherein the plurality of sequence exposures of the imaging system includes mammography exposures and tomosynthesis exposures.

7 . The method of claim 2 , further comprising:

measuring, via the high voltage control circuit, a tube exposure output of the x-ray tube of at least one of the plurality of sequence exposures;

calculating a difference between the measured tube exposure output and a desired tube exposure output based on the stored calibration data; and

adjusting a filament voltage value within the high voltage control circuit when the calculated difference is within a predetermined value.

8 . The method of claim 7 , further comprising alerting, via the imaging system, for a new x-ray tube calibration when the calculated difference is outside of the predetermined value.

9 . The method of claim 7 , wherein the measurement of the tube exposure output is pre-exposure during a mammography exposure.

10 . The method of claim 7 , wherein the measurement of the tube exposure output is post-exposure during a tomosynthesis exposure.

11 . The method of claim 2 , wherein the adjustment of the filament current value within the calibration data is based on a predetermined benchmark value.

12 . The method of claim 11 , wherein the predetermined benchmark value is at least a resistance value change of the filament of at least 2% over at least 5,000 emitted sequence exposures.

13 . The method of claim 11 , wherein the predetermined benchmark value is a measured tube exposure output that is at least 20% different than a desired tube exposure output based on the stored calibration data.

14 . The method of claim 2 , further comprising alerting, via the imaging system, for a replacement x-ray tube when the measured resistance value approaches an upper limit resistance value.

15 . The method of claim 2 , wherein the adjustment of the filament current value within the calibration data occurs for each of the plurality of exposure values based on the determined changed resistance value.

16 . An imaging system comprising:

an x-ray tube having a filament;

a high voltage control circuit operationally coupled to the x-ray tube;

at least one processor communicatively coupled to the high voltage control circuit; and

memory communicatively coupled to the at least one processor, the memory comprising computer executable instructions configured to:

receive calibration data for the x-ray tube, the calibration data including a filament current value for a plurality of exposure values based on different tube current and tube voltage combinations;

store the calibration data;

based on the stored calibration data, control the x-ray tube to emit a plurality of sequence exposures;

measure a resistance value of the filament of the x-ray tube after a predetermined number of sequence exposures of the plurality of sequence exposures;

store each measured resistance value;

determine a change in the stored measured resistance values of the filament, wherein the determined changed resistance value is based on a difference between the stored measured resistance values over a number count of the emitted plurality of sequence exposures; and

adjust the filament current value within the stored calibration data for at least one of the plurality of exposure values based on the determined changed resistance value.

17 . The imaging system of claim 16 , wherein the imaging system is a multi-modal imaging system and includes a mammography mode and a tomosynthesis mode.

18 . The imaging system of claim 16 , wherein the high voltage control circuit includes a monitoring instrument configured to measure one or more electrical properties of the filament.

19 . The imaging system of claim 16 , wherein when the measured resistance value approaches an upper limit resistance value, the imaging system is configured to alert for a replacement x-ray tube.

20 . The imaging system of claim 16 , wherein the computer executable instructions are further configured to:

measure a tube exposure output of the x-ray tube of at least one of the plurality of sequence exposures;

calculate a difference between the measured tube exposure output and a desired tube exposure output based on the stored calibration data; and

alert for a new x-ray tube calibration when the calculated difference is outside of a predetermined value.

21 . The imaging system of claim 16 , wherein the measurement of the resistance value occurs after the filament has cooled after a sequence exposure.