Contrast imaging system and method

Abstract

An imaging system and method acquires non-contrast images of a region of interest in a body and determines an entrance criterion based on the non-contrast images. The entrance criterion dictates conditions in which to begin acquiring contrast imaging exposures of the region of interest. An amount of a contrast agent is measured in one or more locations in the imaged body subsequent to acquiring the non-contrast images. The system and method determine that the one or more conditions of the entrance criterion are met based on the amount of the contrast agent that is measured in the imaged body, and acquire one or more contrast images of the region of interest in the imaged body responsive to determining that the one or more conditions of the entrance criterion are met.

What is claimed is: 
     
         1 . A method comprising:
 acquiring one or more non-contrast images of a region of interest in an imaged body;   determining an entrance criterion based on the one or more non-contrast images, the entrance criterion dictating one or more conditions in which to begin acquiring one or more groups of contrast imaging exposures of the region of interest in the imaged body;   measuring an amount of a contrast agent in one or more locations in the imaged body subsequent to acquiring the one or more non-contrast images of the region of interest in the imaged body;   determining that the one or more conditions of the entrance criterion are met based on the amount of the contrast agent that is measured in the imaged body; and   acquiring one or more contrast images of the region of interest in the imaged body responsive to determining that the one or more conditions of the entrance criterion are met.   
     
     
         2 . The method of  claim 1 , wherein the entrance criterion designates one or more non-zero contrast level thresholds associated with different locations in the region of interest, and the one or more contrast images of the region of interest are acquired responsive to the amount of the contrast agent that is measured at the different locations being at or above the one or more non-zero contrast level thresholds associated with the different locations. 
     
     
         3 . The method of  claim 1 , wherein the entrance criterion designates a rate of change in the amount of the contrast agent that is measured. 
     
     
         4 . The method of  claim 1 , wherein the entrance criterion designates a peak in changes in the amount of contrast agent with respect to time. 
     
     
         5 . The method of  claim 1 , wherein the entrance criterion designates one or more of a positive or negative rate of change in the amount of contrast agent with respect to time. 
     
     
         6 . The method of  claim 1 , further comprising:
 determining an exit criterion that dictates one or more conditions in which to one or more of stop acquiring at least one of the groups of the imaging exposures of the region of interest in the imaged body or transition between acquiring two or more of the groups of the imaging exposures of the region of interest in the imaged body.   
     
     
         7 . The method of  claim 1 , wherein the entrance criterion includes a temporal delay following commencement or completion of a previous group of the imaging exposures of the imaged body before the one or more groups of the contrast imaging exposures are acquired. 
     
     
         8 . The method of  claim 1 , wherein the one or more groups of the contrast imaging exposures include a temporal delay between the contrast imaging exposures of the region of interest in the imaged body. 
     
     
         9 . The method of  claim 8 , wherein the temporal delay is one of plural different temporal delays between the contrast imaging exposures, further comprising:
 automatically changing the different temporal delays such that one or more of an average or a median of the different temporal delays is a designated temporal delay.   
     
     
         10 . An imaging system comprising:
 one or more processors configured to examine one or more non-contrast images of a region of interest in an imaged body and to determine an entrance criterion based on the one or more non-contrast images, the entrance criterion dictating one or more conditions in which to begin acquiring one or more groups of contrast imaging exposures of the region of interest in the imaged body,   wherein the one or more processors also are configured to measure an amount of a contrast agent in one or more locations in the imaged body after acquiring the one or more non-contrast images of the region of interest in the imaged body and to determine that the one or more conditions of the entrance criterion are met based on the amount of the contrast agent that is measured in the imaged body,   wherein the one or more processors also are configured to direct an imaging source and an imaging detector to acquire one or more contrast images of the region of interest in the imaged body responsive to determining that the one or more conditions of the entrance criterion are met.   
     
     
         11 . The system of  claim 10 , wherein the entrance criterion designates one or more non-zero contrast level thresholds associated with different locations in the region of interest, and the one or more processors are configured to direct the imaging source and the imaging detector to acquire the one or more contrast images of the region of interest responsive to the amount of the contrast agent that is measured at the different locations being at or above the one or more non-zero contrast level thresholds associated with the different locations. 
     
     
         12 . The system of  claim 10 , wherein the entrance criterion designates a rate of change in the amount of the contrast agent that is measured. 
     
     
         13 . The system of  claim 12 , wherein the one or more processors are configured to change a rate at which the one or more contrast images are acquired based on the rate of change in the amount of the contrast agent that is measured. 
     
     
         14 . The system of  claim 10 , wherein the entrance criterion designates a peak in changes in the amount of contrast agent with respect to time. 
     
     
         15 . The system of  claim 10 , wherein the entrance criterion designates one or more of a positive or negative rate of change in the amount of contrast agent with respect to time. 
     
     
         16 . A method comprising:
 acquiring image data of a region of interest in an imaged body by exposing the region of interest to multiple imaging exposures within one or more groups of imaging exposures with the imaging exposures in each of the groups separated in time by one or more temporal delays;   changing the one or more temporal delays in at least one of the groups of the imaging exposures based on one or more of a heart rate of a patient having the imaged body, an average or median of the one or more temporal delays, or a measured amount of a contrast agent in the imaged body; and   forming one or more images of the region of interest using the image data.   
     
     
         17 . The method of  claim 16 , wherein changing the one or more temporal delays includes varying durations of the one or more temporal delays with respect to time such that one or more of the average or the median of the one or more temporal delays is a designated temporal delay. 
     
     
         18 . The method of  claim 16 , further comprising:
 measuring the amount of contrast agent in the imaged body; and   terminating acquisition of the image data of the region of interest prior to acquiring a designated number of the imaging exposures based on the amount of contrast agent that is measured.   
     
     
         19 . The method of  claim 16 , further comprising:
 acquiring one or more non-contrast images of the region of interest in the imaged body;   determining an entrance criterion based on the one or more non-contrast images, the entrance criterion dictating one or more conditions in which to begin acquiring the image data from the one or more groups of the imaging exposures;   measuring the amount of contrast agent in one or more locations in the imaged body after acquiring the one or more non-contrast images of the region of interest in the imaged body; and   determining that the one or more conditions of the entrance criterion are met based on the amount of the contrast agent that is measured in the imaged body,   wherein the image data is acquired responsive to determining that the one or more conditions of the entrance criterion are met.   
     
     
         20 . The method of  claim 19 , wherein the entrance criterion includes a temporal delay following commencement or completion of a previous group of the imaging exposures of the imaged body before the one or more groups of the imaging exposures are acquired.