Contrast injector for injecting a contrast medium to generate prolonged uniform vascular enhancement

• US 6,635,030 B1
• Filed: 04/09/1999
• Issued: 10/21/2003
• Est. Priority Date: 04/09/1999
• Status: Expired due to Term

• Current Assignee: Lc Bhb, Liebel-Flarsheim Company (Mallinckrodt plc)
• Original Assignee: Bhb Llc, Liebel-Flarsheim Company (Mallinckrodt plc)
• Inventors: Bae, Kyongtae T., Tran, Huy Q., Small, James R.
• Primary Examiner(s): Casler, Brian L.
• Assistant Examiner(s): Lam, Ann Y.
• Application Number:
  US09/289,289
• Time in Patent Office: 1,656 Days
• Field of Search: 604/131, 604/132, 604/133, 604/134, 604/140, 604/141, 604/145, 604/146, 604/147, 604/148, 604/149, 604/150, 604/151, 604/154, 604/890.1, 604/118-121, 600/431
• US Class Current: 604/131
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 31/005 for contrast media
• CPC Class Codes: A61M 5/007 for contrast media
• CPC Class Codes: A61M 5/14546 Front-loading type injectors
• CPC Class Codes: G16H 20/17 delivered via infusion or injection

Abstract

A contrast medium injector for injecting a patient with contrast medium for a CT scan is programmed to provide an injection protocol that is a representation of an ideally defined exponential curve with an initial injection rate decaying at an exponential rate. This has been found to produce a uniform vascular enhancement for the scanning of a patient'"'"'s blood vessels. The particular exponential decay coefficient which has been found to be optimal is directly proportional to the cardiac output divided by the patient'"'"'s weight and is approximated at 0.01 for a typical human.

Claims

1. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval substantially at a preselected initial injection rate; and

,

a control system having means for controllably changing the injection rate during the injection routine.

2. The apparatus of claim 1, further comprising:

the means for controllably changing the injection rate includes means for ramping the injection rate during at least a part of the injection routine desired interval.

5. The apparatus of claim 1, further comprising:

the control system includes means for determining a volume of contrast agent to be used during the injection routine, a means for determining a desired level of enhancement to be obtained, and a means for determining the desired interval during which the desired level of enhancement is to be substantially achieved.

6. The apparatus of claim 5, further comprising:

the control system having means for adjusting the initial injection rate in proportion to the selected cardiac output typifying said patient.

7. The apparatus of claim 1, further comprising:

the control system having means for adjusting the initial injection rate in proportion to a selected cardiac output per body weight typifying the patient.

3. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval substantially at a preselected initial injection rate;

a control system having means for controllably changing the injection rate during the injection routine;

the means for controllably changing the injection rate includes means for ramping the injection rate during at least a part of the injection routine desired interval; and

,

the means for ramping causes the ramping to be performed substantially throughout the entirety of the injection routine desired interval.

4. A contrast agent intravascular infecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval substantially at a preselected initial injection rate;

a control system having means for controllably changing the injection rate during the injection routine; and

,

the means for controllably changing the injection rate includes means for changing the injection rate at substantially an exponential rate having a coefficient approximating a selected cardiac output per body weight typifying the patient.

8. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval substantially at a preselected initial injection rate;

a control system having means for controllably changing the injection rate during the injection routine; and

,

the means for controllably decreasing the injection rate decreases the injection rate at a rate equal to a substantially linear approximation of an exponential function having as its decay coefficient a value directly proportional to a cardiac output per body weight typifying the patient.

9. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval at a preselected initial injection rate; and

,

a control system having means for substantially continuously changing the injection rate as the routine continues.

10. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval at a preselected initial injection rate;

a control system having means for substantially continuously changing the injection rate as the routine continues; and

,

the means for continuously changing the injection rate includes means for changing the injection rate at substantially an exponential rate having a coefficient approximating a selected cardiac output per body weight typifying the patient.

11. The apparatus of claim 10, further comprising:

the control system includes a means for determining a volume of contrast agent to be used during the injection routine, a means for determining a desired level of enhancement to be attained, and a means for determining the desired interval during which the desired level of enhancement is to be substantially achieved.

12. The method of claim 11, further comprising:

the control system having means for adjusting the initial injection rate in proportion to the selected cardiac output.

13. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning an injection routine desired interval at a preselected initial injection rate;

a control system having means for substantially continuously changing the injection rate as the routine continues; and

,

the control system having means for changing the injection rate at a rate equal to a substantially linear approximation of an exponential function having as its coefficient a value directly proportional to a cardiac output per body weight typifying the patient.

14. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a contrast delivery system having means for beginning the injection routine substantially at a preselected initial injection rate; and

,

a control system having means for substantially continuously changing the injection rate at a changing rate calculated to be substantially dependent on a selected cardiac output per body weight typifying the patient.

15. The apparatus of claim 14, further comprising:

the changing rate is an exponential function having as its coefficient a value directly proportional to cardiac output per body weight typifying the patient.

16. The apparatus of claim 14, further comprising:

the reduction rate is a substantially linear approximation of an exponential function having as its decal coefficient a value directly proportional to a cardiac output per body weight typifying the patient.

17. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a control system having means for implementing a multiphasic injection protocol for injection of the contrast agent.

18. The apparatus of claim 17, further comprising:

contrast delivery system having means for beginning an injection routine substantially at a preselected initial injection rate.

19. A contrast agent intravascular injecting apparatus that substantially maintains a desired level of vascular enhancement in a patient substantially throughout a desired interval of an injection routine, the apparatus comprising:

a control system having means for implementing a multiphasic injection protocol for injection of the contrast agent;

a contrast delivery system having means for beginning an injection routine substantially at a preselected initial injection rate; and

,

the multiphasic injection protocol being an exponential function.

20. The apparatus of claim 19, further comprising:

the exponential function having a decay coefficient of approximately 0.01.