Systems and methods of modeling pharmaceutical propagation in a patient

• US 8,197,437 B2
• Filed: 03/27/2007
• Issued: 06/12/2012
• Est. Priority Date: 11/16/2004
• Status: Expired due to Fees

• Current Assignee: Bayer Healthcare LLC (Bayer AG)
• Original Assignee: Medrad Incorporated (Bayer AG)
• Inventors: Kalafut, John F., Uber, Arthur E. III
• Primary Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US11/691,748
• Publication Number:
  US 20070255135A1
• Time in Patent Office: 1,904 Days
• Field of Search: 604 65- 67, 604/131
• US Class Current: 604/67
• CPC Class Codes: A61B 5/0044 for the heart
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/481 involving the use of contrast agents
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/507 for determination of haemodynamic parameters, e.g. perfusion CT
• CPC Class Codes: A61B 6/583 using calibration phantoms
• CPC Class Codes: A61B 8/13 Tomography A61B8/10, A61B8/12 take precedence; tomography for radiation diagnosis A61B6/02
• CPC Class Codes: A61B 8/481 involving the use of contrast agent, e.g. microbubbles introduced into the bloodstream analysis of echo signal exploiting properties of a contrast enhancer in devices for short-range imaging with acoustic waves G01S7/52039
• CPC Class Codes: A61K 49/0002 General or multifunctional contrast agents, e.g. chelated agents
• CPC Class Codes: A61M 5/007 for contrast media
• CPC Class Codes: G01R 33/5601 involving use of a contrast agent for contrast manipulation, e.g. a paramagnetic, super-paramagnetic, ferromagnetic or hyperpolarised contrast agent
• CPC Class Codes: G16H 30/20 for handling medical images, e.g. DICOM, HL7 or PACS
• CPC Class Codes: G16H 30/40 for processing medical images, e.g. editing
• CPC Class Codes: G16H 50/50 : for simulation or modelling of medical disorders

Abstract

An injection system includes an injector for injecting a fluid into a patient and a controller in operative communication with the injector for control thereof. The controller controls a diagnostic injection of the fluid based upon at least one mathematical model individualized to the patient. The model(s) are determined by collecting data corresponding to a time response curve resulting from at least one test injection of the fluid into the patient. The time response curve represents a response of a region of interest of the patient over time due to the fluid passing therethrough. An imaging system having such an injection system is also disclosed, as is a system for effecting a medical procedure. A method of delivering such a fluid to a patient using such an injection system is also disclosed, as is a method of modeling propagation of such a fluid in a patient.

Claims

1. A method of modeling propagation of a pharmaceutical fluid in a patient, the method comprising the steps of:

(a) injecting during at least one test injection the pharmaceutical fluid into the patient, the pharmaceutical fluid including at least a contrast medium;

(b) collecting data corresponding to at least one of a measurement and an estimate of a concentration of the pharmaceutical fluid in the blood of the patient, the data being indicative of a time enhancement output resulting from the injection of the pharmaceutical fluid into the patient; and

(c) determining at least one mathematical model individualized to the patient that describes the data obtained as a result of the injection of the pharmaceutical fluid into the patient.

2. The method of claim 1 wherein the at least one mathematical model is a parametric model.

3. The method of claim 2 wherein the at least one mathematical model is a moving average or an autoregressive moving average.

4. The method of claim 2 wherein the at least one mathematical model assumes linearity and time invariance.

5. The method of claim 1 wherein the at least one mathematical model is a non-parametric model determined by a spectral estimation technique.

6. The method of claim 5 wherein the spectral estimation technique is Welch'"'"'s method, Bartlett'"'"'s method, a multiple signal classification (MUSIC) method, or the Periodogram method.

7. The method of claim 1 wherein the data is collected during the at least one test injection prior to an imaging injection.

8. The method of claim 7 wherein the at least one mathematical model is updated with additional data collected during the imaging injection.

9. The method of claim 7 wherein the at least one test injection comprises an injection of the contrast medium followed by an injection of a non-contrast fluid.

10. The method of claim 9 wherein the non-contrast fluid is injected at substantially the same volumetric flow rate as a flow rate of the contrast medium preceding the injection of the non-contrast fluid.

11. The method of claim 10 wherein the non-contrast fluid is saline.

12. The method of claim 7 wherein more than one test injection is performed during the least one test injection.

13. The method of claim 12 wherein one test injection comprises injection of the contrast medium only and another test injection comprises injection of the contrast medium followed by injection of a non-contrast fluid.

14. A method of controlling injection of a pharmaceutical fluid into a patient using an injector in a medical procedure, the method comprising the steps of:

(a) collecting data corresponding to a patient response curve resulting from a test injection of the pharmaceutical fluid into the patient, the pharmaceutical fluid including at least a contrast medium;

(b) determining at least one mathematical model individualized to the patient that describes the data obtained as a result of the test injection of the pharmaceutical fluid into the patient; and

(c) subsequent to the test injection, controlling the injector during the medical procedure to control administration of an imaging injection of the pharmaceutical fluid into the patient to create a patient response at least in part on the basis of the at least one mathematical model determined from the data obtained as a result of the test injection of the pharmaceutical fluid into the patient.

15. The method of claim 14 wherein the medical procedure is an imaging procedure using an imaging scanner, the patient response curve is a time enhancement curve representing enhancement of a region of interest of the patient over time due to the test injection of the contrast medium, and the injector is controlled to control the imaging injection of the contrast medium into the patient to create during the imaging procedure an image of the region of interest at least in part on the basis of the at least one mathematical model.

16. The method of claim 15 wherein the at least one mathematical model is a parametric model.

17. The method of claim 16 wherein the at least one mathematical model is a moving average or an autoregressive moving average.

18. The method of claim 17 wherein the at least one mathematical model assumes linearity and time invariance.

19. The method of claim 15 wherein the at least one mathematical model is a non-parametric model determined by a spectral estimation technique.

20. The method of claim 19 wherein the spectral estimation technique is Welch'"'"'s method, Bartlett'"'"'s method, a multiple signal classification (MUSIC) method, or the Periodogram method.

21. The method of claim 15 wherein the injector is also controlled at least in part on the basis of information regarding the patient response during the imaging procedure.

22. The method of claim 15 wherein the injector is also controlled at least in part on the basis of information on at least one measured physiological variable of the patient.

23. The method of claim 22 wherein the at least one measured physiological variable is used to alter the output of the at least one mathematical model.

24. The method of claim 15 wherein the step of controlling the injector comprises commencing the imaging injection of the contrast medium at one time and commencing an image scan of the region of interest at a second time determined at least in part on the basis of the at least one mathematical model.

25. The method of claim 24 wherein the second time is determined on the basis of a prediction of a time of attainment of a predetermined enhancement level as determined by the at least one mathematical model.

26. The method of claim 14 wherein the at least one mathematical model is updated with data collected during the imaging injection.

27. The method of claim 14 wherein the test injection comprises an injection of the contrast medium followed by an injection of a non-contrast fluid.

28. The method of claim 27 wherein the non-contrast fluid is injected at substantially the same volumetric flow rate as a flow rate of the contrast medium preceding the injection of the non-contrast fluid.

29. The method of claim 28 wherein the non-contrast fluid is saline.

30. The method of claim 14 wherein more than one test injection is performed during the at least one test injection.

31. The method of claim 30 where one test injection comprises injection of the contrast medium only and another test injection comprises injection of the contrast medium followed by injection of the non-contrast fluid.

32. An injection system comprising:

(a) an injector for injecting a fluid into a patient; and

(b) a controller in operative communication with the injector to control the injector, the controller controlling a diagnostic injection of the fluid based upon at least one mathematical model individualized to the patient, the at least one mathematical model being determined by collecting data corresponding to a time enhancement curve resulting from at least one test injection of a contrast medium into the patient, the time enhancement curve representing enhancement of a desired region of interest of the patient over time due to the contrast medium passing therethrough.

33. The injection system of claim 32 wherein the controller comprises a computer comprising at least one processing unit and at least one memory, the at least one memory having stored therein a computer program to determine the at least one mathematical model.

34. A system for effecting a medical procedure, the system comprising:

(a) a sensing system to detect a patient response;

(b) an injector adapted to inject a pharmaceutical fluid; and

(c) a controller in operative communication with the injector to control the injector, the controller controlling a diagnostic injection of the pharmaceutical fluid based upon at least one mathematical model individualized to the patient, the at least one mathematical model being determined by collecting data from the sensing system corresponding to a time response curve resulting from a test injection of the pharmaceutical fluid into the patient, the time response curve representing a response of a desired region of interest of the patient over time to the pharmaceutical fluid passing therethrough due to the test injection thereof.

35. An imaging system comprising:

(a) an imager to create an image of a region of interest of a patient;

(b) an injector adapted to inject a contrast medium into the patient; and

(c) a controller in operative communication with the injector to control the injector, the controller controlling a diagnostic injection of the contrast medium based upon at least one mathematical model individualized to the patient, the at least one mathematical model being determined by collecting data from the imager corresponding to a time enhancement curve resulting from a test injection of the contrast medium into the patient, the time enhancement curve representing enhancement of the region of interest over time due to the contrast medium passing therethrough.