Ultrasound diagnostic system, ultrasound image generation apparatus, and ultrasound image generation method

Abstract

The ultrasound diagnostic apparatus, ultrasound image generation apparatus and method transmit ultrasound waves to a subject into which a puncture tool is inserted, receive reflected waves reflected from the subject and the puncture tool, and generate echo signals of time-sequential frames based on the received reflected waves, and generate an ultrasound image of the subject based on the generated echo signals. These apparatus and method generate a differential echo signal between time-sequential frames from the echo signals, perform a tip detection process based on the differential echo signal to thereby detect at least one tip candidate including a tip end of the puncture tool, highlight a tip candidate of the puncture tool detected to thereby generate a tip image, and display the tip image of the highlighted puncture tool so as to be superimposed on the generated ultrasound image.

What is claimed is: 
     
         1 . An ultrasound diagnostic apparatus comprising:
 an ultrasound transceiving unit that transmits ultrasound waves toward a subject to be examined into which a puncture tool is inserted, receives reflected waves of the ultrasound waves reflected from the subject and the puncture tool, and generates echo signals of time-sequential frames based on the received reflected waves;   an ultrasound image generation unit that generates an ultrasound image of the subject based on the echo signals generated by the ultrasound transceiving unit;   an image display unit that displays the ultrasound image generated by the ultrasound image generation unit;   a differential image generation unit that generates a differential image between time-sequential frames from the ultrasound images of time-sequential frames generated by the ultrasound image generation unit;   a tip candidate detection unit that performs a tip detection process based on the differential image generated by the differential image generation unit to thereby detect at least one tip candidate including a tip end of the puncture tool; and   a tip candidate processing unit that highlights a tip candidate of the puncture tool detected by the tip candidate detection unit to thereby generate a tip image in which one or more tip candidates of the puncture tool are highlighted,   wherein the image display unit displays the tip image of the puncture tool highlighted by the tip candidate processing unit so as to be superimposed on the ultrasound image generated by the ultrasound image generation unit.   
     
     
         2 . An ultrasound image generation method comprising:
 transmitting ultrasound waves to a subject to be examined into which a puncture tool is inserted;   receiving reflected waves of the ultrasound waves reflected from the subject and the puncture tool;   generating echo signals of time-sequential frames based on the received reflected waves;   generating an ultrasound image of the subject based on the generated echo signals;   generating a differential image between time-sequential frames from the generated ultrasound images of the time-sequential frames;   performing a tip detection process based on the generated differential image to thereby detect at least one tip candidate including a tip end of the puncture tool;   highlighting a tip candidate of the puncture tool detected; and   displaying the tip candidate of the puncture tool on a display unit so as to be superimposed on the generated ultrasound image.   
     
     
         3 . An ultrasound image generation apparatus in which ultrasound waves are irradiated from a probe toward a subject to be examined into which a puncture tool is inserted, echoes reflected from the subject and the puncture tool are received by the probe, and an ultrasound image is generated from the echo signals output from the probe, the apparatus comprising:
 a candidate point extraction unit that extracts plural candidate points of the puncture tool based on the ultrasound image;   a puncture tool presence region specifying unit that specifies a puncture tool presence region in which the puncture tool is likely to be present in the ultrasound image from a distribution of the plural candidate points extracted by the candidate point extraction unit; and   a puncture tool tip position specifying unit that specifies a tip position of the puncture tool based on an intensity distribution on a line that includes the puncture tool in the puncture tool presence region specified by the puncture tool presence region specifying unit.   
     
     
         4 . The ultrasound image generation apparatus according to  claim 3 , further comprising:
 a puncture tool image generation unit that generates a puncture tool image representing the puncture tool based on the tip position of the puncture tool specified by the puncture tool tip position specifying unit; and   an image combination unit that displays the puncture tool image generated by the puncture tool image generation unit so as to be superimposed on the ultrasound image.   
     
     
         5 . The ultrasound image generation apparatus according to  claim 4 ,
 wherein the puncture tool presence region specifying unit generates a puncture tool candidate line from the plural candidate points extracted by the candidate point extraction unit and specifies a region including the puncture tool candidate line as the puncture tool presence region, and   wherein the puncture tool image generation unit generates the puncture tool image based on the tip position of the puncture tool and the puncture tool candidate line.   
     
     
         6 . The ultrasound image generation apparatus according to  claim 4 , further comprising:
 a puncture tool information storage unit that stores information on the puncture tool,   wherein the puncture tool image generation unit determines a shape of the puncture tool image using the information on the puncture tool stored in the puncture tool information storage unit.   
     
     
         7 . The ultrasound image generation apparatus according to  claim 3 ,
 wherein the puncture tool tip position specifying unit specifies the tip position of the puncture tool based on the maximum and minimum values of the intensity distribution on the line that includes the puncture tool in the puncture tool presence region.   
     
     
         8 . The ultrasound image generation apparatus according to  claim 3 ,
 wherein the puncture tool presence region specifying unit performs Hough transform on the plural candidate points extracted by the candidate point extraction unit to thereby generate the puncture tool candidate line.   
     
     
         9 . The ultrasound image generation apparatus according to  claim 3 ,
 wherein the candidate point extraction unit performs threshold processing on the ultrasound image to thereby extract the candidate points of the puncture tool.   
     
     
         10 . The ultrasound image generation apparatus according to  claim 3 , further comprising:
 a predicted insertion region setting unit that sets a predicted insertion region to which the puncture tool is highly likely to be inserted in the ultrasound image,   wherein the candidate point extraction unit extracts the candidate points of the puncture tool from the predicted insertion region set by the predicted insertion region setting unit.   
     
     
         11 . The ultrasound image generation apparatus according to  claim 3 , further comprising:
 a predicted insertion region setting unit that sets a predicted insertion region to which the puncture tool is highly likely to be inserted in the ultrasound image,   wherein the puncture tool presence region specifying unit specifies the puncture tool presence region from candidate points included in the predicted insertion region set by the predicted insertion region setting unit among the plural candidate points of the puncture tool extracted by the candidate point extraction unit.   
     
     
         12 . The ultrasound image generation apparatus according to  claim 10 ,
 wherein the predicted insertion region setting unit sets the predicted insertion region based on an angle or a position at which the puncture tool is inserted into the subject.   
     
     
         13 . The ultrasound image generation apparatus according to  claim 10 , further comprising:
 a tip position storage unit that stores plural past tip positions of the puncture tool specified by the puncture tool tip position specifying unit,   wherein the predicted insertion region setting unit estimates an advancing direction of the puncture tool from the plural tip positions of the puncture tool stored in the tip position storage unit and sets a region located in the advancing direction of the puncture tool as the predicted insertion region.   
     
     
         14 . The ultrasound image generation apparatus according to  claim 3 , further comprising:
 a target region setting unit that sets a target region where the puncture tool is present; and   an image quality enhancing unit that enhances image quality of the target region set by the target region setting unit in relation to regions other than the target region.   
     
     
         15 . An ultrasound image generation method in which ultrasound waves are irradiated from a probe toward a subject to be examined into which a puncture tool is inserted, echoes reflected from the subject and the puncture tool are received by the probe, and an ultrasound image is generated from the echo signals output from the probe, the method comprising:
 a candidate point extraction step of extracting plural candidate points of the puncture tool based on the ultrasound image;   a puncture tool presence region specifying step of specifying a puncture tool presence region in which the puncture tool is likely to be present in the ultrasound image from a distribution of the plural candidate points extracted in the candidate point extraction step; and   a puncture tool tip position specifying step of specifying a tip position of the puncture tool based on an intensity distribution on a line that includes the puncture tool in the puncture tool presence region specified in the puncture tool presence region specifying step.   
     
     
         16 . An ultrasound image generation apparatus in which ultrasound waves are irradiated from a probe toward a subject to be examined into which a puncture tool is inserted, echo signals reflected from the subject and the puncture tool are received by the probe, and an ultrasound image is generated from the echo signals and displayed on a display unit, the apparatus comprising:
 an insertion angle acquisition unit that acquires an insertion angle at which the puncture tool is inserted into the subject;   a puncture tool enhancement processing unit that applies a puncture tool enhancement filter based on the insertion angle to thereby enhance the puncture tool within the ultrasound image;   an image combination unit that combines images before and after the puncture tool enhancement processing to thereby generate a combined image; and   a display controller that causes the combined image to be displayed on the display unit.   
     
     
         17 . The ultrasound image generation apparatus according to  claim 16 ,
 wherein the puncture tool enhancement filter has an aspect ratio which is determined by the insertion angle.   
     
     
         18 . The ultrasound image generation apparatus according to  claim 16 ,
 wherein the puncture tool enhancement filter has a size which is determined based on an interval on the ultrasound image, at which an image representing the puncture tool is disconnected.   
     
     
         19 . The ultrasound image generation apparatus according to  claim 16 , further comprising:
 a speckle noise removal unit that removes speckle noise in the ultrasound image,   wherein the puncture tool enhancement processing unit performs the puncture tool enhancement processing using the puncture tool enhancement filter on the ultrasound image in which the speckle noise is removed by the speckle noise removal unit.   
     
     
         20 . The ultrasound image generation apparatus according to  claim 16 , further comprising:
 a layer structure removal unit that removes a layer structure in the ultrasound image,   wherein the puncture tool enhancement processing unit performs the puncture tool enhancement processing using the puncture tool enhancement filter on the ultrasound image in which the layer structure is removed by the layer structure removal unit.   
     
     
         21 . The ultrasound image generation apparatus according to  claim 16 , further comprising:
 a speckle noise removal unit that removes speckle noise in the ultrasound image; and   a layer structure removal unit that removes a layer structure in the ultrasound image,   wherein the puncture tool enhancement processing unit performs the puncture tool enhancement processing using the puncture tool enhancement filter on the ultrasound image in which the speckle noise is removed, and subsequently, the layer structure is removed.   
     
     
         22 . The ultrasound image generation apparatus according to  claim 16 , further comprising:
 a puncture tool connection processing unit that performs a puncture tool connection process of connecting disconnected parts of an image representing the puncture tool on the ultrasound image.   
     
     
         23 . The ultrasound image generation apparatus according to  claim 16 , further comprising:
 a filter storage unit that stores plural puncture tool enhancement filters corresponding to the insertion angle,   wherein the puncture tool enhancement processing unit specifies the puncture tool enhancement filter to be used from the plural puncture tool enhancement filters stored in the filter storage unit.   
     
     
         24 . The ultrasound image generation apparatus according to  claim 16 ,
 wherein the insertion angle acquisition unit acquires the insertion angle from a puncture adapter which serves as a guide that inserts the puncture tool into the subject.   
     
     
         25 . The ultrasound image generation apparatus according to  claim 16 ,
 wherein the insertion angle acquisition unit extracts plural tip positions of the puncture tool from the ultrasound image and acquires the insertion angle from the plural extracted tip positions.   
     
     
         26 . An ultrasound image generation apparatus in which ultrasound waves are irradiated from a probe toward a subject to be examined into which a puncture tool is inserted, echo signals reflected from the subject and the puncture tool are received by the probe, and an ultrasound image is generated from the echo signals and displayed on a display unit, the apparatus comprising:
 an insertion angle acquisition unit that acquires an insertion angle at which the puncture tool is inserted into the subject;   an image rotation unit that rotates the ultrasound image based on the insertion angle so that an angle of the puncture tool displayed on the display unit becomes horizontal;   a puncture tool enhancement processing unit that applies a puncture tool enhancement filter to thereby enhance the puncture tool within the rotated ultrasound image;   an image combination unit that combines images before and after the puncture tool enhancement processing to thereby generate a combined image; and   a display controller that causes the combined image to be displayed on the display unit.   
     
     
         27 . An ultrasound image generation method in which ultrasound waves are irradiated toward a subject to be examined into which a puncture tool is inserted, and an ultrasound image is generated from echo signals reflected from the subject and the puncture tool and is displayed on a display unit, the method comprising:
 an insertion angle acquisition step of acquiring an insertion angle at which the puncture tool is inserted into the subject;   a puncture tool enhancement processing step of applying a puncture tool enhancement filter based on the insertion angle to thereby enhance the puncture tool within the ultrasound image;   an image combination step of combining images before and after the puncture tool enhancement processing to thereby generate a combined image; and   a displaying step of causing the combined image to be displayed on the display unit.   
     
     
         28 . An ultrasound image generation method in which ultrasound waves are irradiated toward a subject to be examined into which a puncture tool is inserted, and an ultrasound image is generated from echo signals reflected from the subject and the puncture tool and is displayed on a display unit, the method comprising:
 an insertion angle acquisition step of acquiring an insertion angle at which the puncture tool is inserted into the subject;   an image rotation step of rotating the ultrasound image based on the insertion angle so that an angle of the puncture tool displayed on the display unit becomes horizontal;   a puncture tool enhancement processing step of applying a puncture tool enhancement filter to thereby enhance the puncture tool within the rotated ultrasound image;   an image combination step of combining images before and after the puncture tool enhancement processing to thereby generate a combined image; and   a displaying step of causing the combined image to be displayed on the display unit.