CN100589760C - X-ray CT device and image processing device - Google Patents

Abstract

An X-ray CT apparatus according to the present invention includes: a unit (20) for extracting a high contrast region having a relatively high X-ray attenuation coefficient from the image; means (21, 22) for generating a blurred image concerning the high-contrast region on the basis of the extracted position of the high-contrast region and a point image intensity distribution function unique to the apparatus; a unit (23) for subtracting the blurred image from the image in order to generate a low contrast image associated with a low contrast area where the X-ray attenuation coefficient is relatively low.

Description

X ray CT device and image processing apparatus

Technical field

The present invention relates to generate the X ray CT device and the image processing apparatus of the image of subject inside according to subject is shone the data for projection that X ray obtains.

Background technology

The progress of X ray CT device is very remarkable, with hope higher meticulous (high-resolution) and in wide scope, photograph from the on-the-spot strong desire of medical treatment correspondingly, in recent years, developed many sections X ray CT device, it is considerably popularized.Should possess by many section X ray CT devices: irradiation tangential section direction (length direction of Wo Tai) expansion and have the x-ray source of the fan beam X ray of width; Having the 2 dimension detectors of structure of having arranged the detecting element row of multiple row (4 row, 8 row, 16 row etc.) at slice direction, is the scanning device that makes its action by many scannings or helical scanning.Thus, compare with single section X ray CT device, can high accuracy and in the short time, obtain volume data (volume data) in the wide scope of subject.

Have near at hand under the situation of high-contrast material (material with high X ray attenuation quotient) by the blood vessel in the CT image of such X ray CT device generation, be subjected to its fuzzy influence, the appearance of intravascular space is not distinct.Now, improve the method for the image quality of region-of-interest as the influence that is not subjected to high-contrast area, known following method: be set to carry out Flame Image Process after the suitable value consistent in the CT of high-contrast area value with on every side CT value, then, the value of recovery high-contrast area.But, in the method, can't remove high-contrast area fuzzy (opening flat 10-40372 communique) on every side well with reference to the spy.

Summary of the invention

The objective of the invention is to: absorb at the X ray that shows the subject inside obtain by X ray CT device under the situation of distributed image, be reduced in produce around the object of high X ray attenuation quotient fuzzy.

A first aspect of the present invention provides a kind of X ray CT device, be to collect the data for projection relevant with subject,, possess in the X ray CT device of the image of the inside of the above-mentioned subject of reconstruct according to the above-mentioned data for projection of collecting: constitute and from above-mentioned image, extract the unit that X ray declines into the higher high-contrast area of coefficient ratio out; Constitute according to the position and the device of the high-contrast area of above-mentioned extraction inherently, produce the unit of the broad image relevant with above-mentioned high-contrast area as intensity distribution function; Constitute in order to produce the low contrast regions relevant soft image lower, from the unit of the above-mentioned broad image of above-mentioned figure image subtraction with the X ray attenuation quotient.

A second aspect of the present invention provides a kind of X ray CT device, be to collect the data for projection relevant with subject, according to the above-mentioned data for projection of collecting and in the X ray CT device of the image of the inside of the above-mentioned subject of reconstruct, possess: constitute in order to produce the relevant soft image in zone lower, from the unit of the above-mentioned figure image subtraction broad image more relevant than higher zone with the X ray attenuation quotient being included in above-mentioned image with the X ray attenuation quotient; Accordingly above-mentioned soft image is categorized as the unit in a plurality of zones with the CT value; The pixel value of above-mentioned soft image is replaced into the unit of inherent value separately, above-mentioned a plurality of zones of having classified.

A third aspect of the present invention provides a kind of X ray CT device, be to collect the data for projection relevant with subject, according to the above-mentioned data for projection of collecting and in the X ray CT device of the image of the inside of the above-mentioned subject of reconstruct, possess: from above-mentioned image, according to a plurality of threshold values, sequentially extract a plurality of regional candidates' that vary in size that comprised unit out; Calculate the unit of a plurality of regional candidate center of gravity separately of above-mentioned extraction; According to the distance between the above-mentioned center of gravity, from a plurality of regional candidate of above-mentioned extraction, select the unit in specific zone.

Description of drawings

Fig. 1 is the structure chart of X ray CT device of the present invention.

Fig. 2 is the structure chart of the Flame Image Process parts of embodiments of theinvention 1.

Fig. 3 is the key diagram of transfer function.

Fig. 4 is the structure chart of the Flame Image Process parts of embodiments of the invention 2.

Fig. 5 is the structure chart of the classification processing unit of embodiments of the invention 2.

Fig. 6 is 3 zones cutting apart are handled in expression by classification figure.

Fig. 7 is the flow chart that the zone of the zone decision parts ofpresentation graphs 5 determines treatment step.

Fig. 8 be Fig. 7 S13 supply figure.

Fig. 9 is the figure that is illustrated inregion R 1 of extracting out among the S14 of Fig. 7 and the position of centre of gravity B1 that calculates in S15.

Figure 10 is the figure that is illustrated in region R 2 of extracting out among the S14 of Fig. 7 and the position of centre of gravity B2 that calculates in S15.

Figure 11 is the figure that is illustrated in region R 3 of extracting out among the S14 of Fig. 7 and the position of centre of gravity B3 that calculates in S15.

The specific embodiment

(embodiment 1)

Below, embodiments of theinvention 1 are described.

Fig. 1 is the structure chart of the X ray CT device of embodiment 1.Xray CT device 1 possesses: constitute the pallet 2 of collecting the data for projection relevant with subject; The platform for sleeping in 3 that is used for mounting subject P and moves it; Be used for the input of operation of X ray CT device and the operating console of pictorial display.

Pallet 1 hasX-ray tube 5 and X-ray detector 6.X-ray tube 5 andX-ray detector 6 are installed on the cyclic rotatingframe 8 that is driven by 7 rotations of pallet driving device.The platform 3 that crouches possess the mountingsubject top board 8, be used to topboard driving device 9 thattop board 8 is moved.Rotating frame 8 part in the central has opening.The subject P that is positioned on thetop board 8 is inserted in this opening.In addition, with the rotary middle spindle of Z axle (slice direction axle)definition rotating frame 8, with vertical 2 definition and the vertical plane of Z axle of XY.

Between the negative electrode anode ofX-ray tube 5, apply tube voltage from high voltage generator 10.Supply with heater current fromhigh voltage generator 10 to the filament of X-ray tube 5.The supply with heater current of applying by tube voltage produces X ray.ForX-ray detector 6, adopt 1 dimension array-type detector or 2 dimension array-type detectors (being also referred to as many sections type detector).X-ray detection device for example has the foursquare sensitive surface of 0.5mm * 0.5mm.For example on the channel direction, arrange 916 x-ray detection devices.For example being set up in parallel 40 these row on slice direction, then is 2 dimension array-type detectors.By single row constitute be 1 the dimension array-type detector.

Transacter 11 is commonly referred to as DAS (data acquisition system).Transacter 11 will be transformed to voltage signal and amplify from the signal thatdetector 6 is exported each channel, and then will be transformed to digital signal.These data (initial data) are supplied with theoperating console 4 of pallet outside.

12 pairs of data (initial data) from transacter 11 outputs of the pre-treatment parts ofoperating console 4 are implemented correcting process such as sensitivity correction, the output data for projection.This data for projection is sent to reconstruction processing parts 13.Reconstruction processing parts 13 for example according to by helical scanning, used the swept-volume of conical beam X ray or used the data for projection that they collect simultaneously, reconstructed image data, and storing in the image storage part spare 14.FlameImage Process parts 15 generate display image according to the view data that is stored in the image storage part spare 14.According to the input of operator, be used for being provided with etc. of condition setting, region-of-interest of display image to input equipment 16.To describe the image processing unit in the back indetail.Display device 17 is presented at the image that generates in the Flame Image Process parts 15.In addition, thescan control parts 18 ofoperating console 4 are according to operator's input, and control highpressure generating apparatus 10, pallet driving device 7, transacter 11, topboard driving device 9 make scannings such as carrying out helical scanning.In addition,operating console 4 can constitute with specialized hardware, also can use a computer to realize same function with software.

Fig. 2 is the figure of structure of the FlameImage Process parts 15 of key diagram 1.In addition, Fig. 2 (A) is the ideograph as the blood vessel cross-section structure of an example of Flame Image Process object.Comprise blood vessel wall P1, support P2, contrast agent (blood flow part) P3, fatty P4.Below, the situation of having carried out handling with the image to such entity is that example describes.

FlameImage Process parts 15 possess region-of-interestimage extraction parts 19, high-contrast extraction parts 20,convolution parts 21, CT value proportional zoom (scaling)parts 22,subtractor 23,adder 24 are set.

Region-of-interest is provided with image andextracts parts 19 out according to the input toinput equipment 16, and region-of-interest is set, and extracts the view data and the output of this region-of-interest out from image storage part spare 14.(B) expression of Fig. 2 is provided with the image that image is extracted the region-of-interest ofparts 19 extractions out by region-of-interest.

High-contrast is extractedparts 20 out from the image by the region-of-interest of extractingparts 19 extractions out, extracts the very high high-contrast area of X ray attenuation quotient out, the pixel group that promptly has very high CT value.As the high-contrast material, have imbed metallicity utensils such as tested intravital support, calcification for treatment calcium etc.In addition, the high-contrast material as in the soft image of having removed support etc. described later is not support etc., but is object with contrast agent mainly.Optionally use contrast agent with the CT value between support and the blood vessel wall.

Handle as concrete extraction, difference between the meansigma methods of the value by obtaining concerned pixel and the value of a plurality of pixels around this concerned pixel, obtain the differential map picture of the image of input, by using this differential map picture is implemented threshold process, obtain binary image with the edge corresponding threshold of support.This binary image is the different image of pixel value in the part that may have the high-contrast material and in addition part.That is, this binary picture similarly is the image (hereinafter referred to as high-contrast location drawing picture) that comprises the information of the position that may have the high-contrast material.(C) of Fig. 2 represents this high-contrast location drawing picture.In its differential, binary conversion treatment, can easily obtain high-contrast location drawing picture with fewer computing.

Convolution parts 21 are at high-contrast location drawing picture, and this X ray computer laminagraph device of convolutional calculation is inherent as intensity distribution function (PSF:point spread function).PSF is also referred to as transfer function or ambiguity function as the function of the inherent fuzzy behaviour of definition device.The line photofit picture that for example has its diameter of 1/10 (0.05mm) that for example 0.5mm of the detector spacings of PSF comparison and detection device 6 (resolution gauge) is more small scans, the data of the 2 dimension images (broad image) relevant with the line photofit picture that obtain obtaining by reconstruct according to this data for projection.This PSF and the high-contrast location drawing are looked like to carry out convolution, obtain according to individually high contrast object being scanned the image that the data that obtain reconstruct the fuzzy image that promptly comprises high contrast object and around it, occur thus.

CT valueproportional zoom parts 22 be standard CT value as contrast agent at this promptly according to as CT value value especially, and the image of exporting from convolution parts 21 (broad image) is carried out standardization (proportional zoom).This standardization is the processing that is used for the pixel value level of subtraction process described later.(D) expression of Fig. 2 is from the image (hereinafter referred to as high-contrast image) of CT valueproportional zoom parts 22 outputs.

Subtraction parts 23 carry out subtraction process, obtain the image of region-of-interest and the difference image of high-contrast image.Thus, from the be reduced soft image of high-contrast material and fuzzy composition on every side thereof of the image of region-of-interest.This soft image is the image of the material of expression lower attenuation coefficient.Fig. 2 (E) represents this soft image.

Addingunit 24 adds the positional information of high-contrast material by the high-contrast location drawing is looked like to add this soft image.Fig. 2 (F) represents this output image.This output image is that the positional information with the high-contrast material is added to from the image of original region-of-interest and has reduced image on the image of fuzzy (pseudomorphism) that the high-contrast material causes, is presented in thedisplay device 17 via the processing of back level.In this output image, can observe well in original image because fuzzy influence and fat around the impalpable high-contrast material.

According tosuch embodiment 1, can be reduced in the fuzzy composition that produces of high-contrast material on every side, therefore can observe high-contrast material material on every side well.Have under support or the calcific situation in the blood capillary of the diameter of 5mm at the such 3mm that has of the coronary artery of heart especially, can observe the blood vessel wall around it, the savings state of fat, the state of contrast agent etc. well.

Also can carry out various distortion and implement this embodiment 1.For example, in the above-described embodiments, added high-contrast location drawing picture, but also can not addition, and only carry out the demonstration of soft image.In addition, the different sign of color of the position of all right overlapping expression high-contrast material.

And then, in the above-described embodiments, X ray CT device has been described, but also can the medical image-processing apparatus of the demonstration of carrying out image according to the data for projection of exporting from X ray CT device, CT image etc., have implemented.And then, in the above-described embodiments, 2 dimension treatment of picture have been described, but also can have carried out the processing of 3 d image by a plurality of 2 dimension images are carried out above-mentioned processing.

And then in the above-described embodiments, the pixel value that image has been described is the situation of CT value, but if expression X ray attenuation quotient then also can be the value beyond the CT value.In addition, in the above-described embodiments, obtained high-contrast location drawing picture by differential, binary conversion treatment, but also can use following method:, obtained the method for high-contrast location drawing picture the fuzzy transfer function that the contrary Using Convolution high-contrast material of image causes; The information of the position of storage support, shape is obtained the method for positional information etc. according to this information in advance.

(embodiment 2)

Below, embodiments of the invention 2 are described.In addition, omit explanation to the part identical withembodiment 1.

Embodiment 2 handles by classification (clustering), automatically classifies to make similar substance in the easy recognition image.Known under ideal condition, the CT value of platelet or fat expression-100 to 50, blood vessel wall is represented 50 to 129 CT value, is included in the CT value that contrast agent in the blood flow is represented 130-350.But, in the inspection of reality, being subjected to the influence of physique, beam hardening, the reconstruction of function of subject, the size of material, the state of the material beyond the region-of-interest, the concentration of contrast agent etc., CT has change.Therefore, in the method for carrying out zone extraction (Region Segmentation), the change of CT value that can't be corresponding such can't be classified well.In the present embodiment, from soft image, extract the main regional A corresponding, main area B, main with the contrast agent corresponding zone C corresponding accurately out with blood vessel wall with platelet.

Fig. 4 is the structure chart of the Xray CT device 1 of embodiment 2.In Fig. 4, betweensubtraction parts 23 and addingunit 24, has classification processing unit 25.Thisclassification processing unit 25 is obtained a plurality of zones of regulation according to the CT value, and carries out the conversion process of CT value, makes to show each zone with same brightness or color.In addition, in the present embodiment, the situation that the CT value is divided into 3 zones has been described, but number that should the zone also can be other numbers.In addition, also can change number of regions accordingly with operator's input.

Fig. 5 is the structure chart of classification processing unit 25.Classification processing unit 25 possesses histogram generating means 26,zone decision parts 27, CT value transform parts 28.Histogram generating means 26 is obtained the rectangular histogram of the soft image of being imported.Rectangular histogram represents that the frequency that the pixel of each CT value occurs distributes.At this, the CT value is distributed in the scope between-100 to 537.

Decision parts 27 in zone are for example extracted 3 regional A, B, C out as shown in Figure 6 from soft image.Zone A is mainly corresponding to platelet.Area B is mainly corresponding to blood vessel wall.Zone C is mainly corresponding to contrast agent.

Fig. 7 represents to be extracted out from soft image byzone decision parts 27 step of the processing of 3 regional A, B, C.At first, from soft image, extract vascular wall area B (S11) out.From approximate centre a plurality of tracker wires are set radially by the specified blood vessel of operator.Follow the tracks of the CT value along each tracker wire.The position that the change of CT value is bigger, i.e. expression is defined as the interior point and the exterior point of blood vessel wall above 2 positions of the differential value of setting.Then, from soft image, extract platelet zone A (S12) out.As platelet zone A, extract the pixel group with CT value lower of the inboard that is positioned at blood vessel wall out than blood vessel wall.

Then, extract the zone C (S13～S19) of contrast agent out.At first, example is such as shown in Figure 8, and by the k-means method, the scope (in Fig. 6, the scope for-100 to 537) that the CT value on the rectangular histogram is distributed is divided into N section SEG₁～SEG_N(S13).If the section that the CT value is the highest is SEG₁N is set to surpass the integer that final classified regions is counted n (at this n=3).It is desirable to N is set to final classified regions and counts 2 times or 3 times of n.M is a treatment variable.M is initialized as 1.

At first, as shown in Figure 9, from soft image, extract out and section SEG₁Corresponding regional candidate R₁(S14).With section SEG₁Minimum as threshold value, from soft image, extract region R out₁The regional candidate R that calculating has been extracted out₁Position of centre of gravity B₁(S15).In S17, variable m is added 1 (S17).In addition, in S18, as the stop condition that is used to prevent spread, judge the minima of " CTmin seg m＜CTmax/2 " CTmin seg m section of being m, CTmax is the maximum CT value of soft image.That is, in the minima ofsection m 1/2 o'clock, stop area processing and amplifying less than the maximum CT value of soft image.During No in S18, carry out S19.During Yes in S18, turn back to S14.

As shown in Figure 10, from soft image, extract out and section SEG₁With section SEG₂Corresponding regional candidate R₂(S14).In fact, with section SEG₂Minimum as threshold value, from soft image, extract regional candidate R out₂The regional candidate R that calculating has been extracted out₂Position of centre of gravity B₂(S15).Calculate this zone candidate R₂Position of centre of gravity B₂With a regional candidate R before₁Position of centre of gravity B₁Between distance D₂, and with the regulation threshold value Th compare (S16).

Addendum modification D up to position of centre of gravity_mSurpass till the threshold value Th, the processing of S14～S18 is carried out in circulation.That is, along with increasing progressively of variable m, regional candidate R enlarges bit by bit.Along with the expansion of regional candidate R, center of gravity B displacement.When the extraction object was identical, the addendum modification of center of gravity B was fewer.Enlarging when make extracting object out and comprising other materials, the addendum modification of center of gravity B is bigger.That is, extract out to as if during contrast agent, even the enlarged area candidate R, position of centre of gravity does not roughly change yet.But when having added blood vessel wall etc. in extracting object out, regional candidate R becomes greatly by leaps and bounds, and also great changes have taken place for position of centre of gravity.The search position of centre of gravity section that great changes have taken place.

When m=3, as shown in figure 11, at regional candidate R₃Position of centre of gravity B₃With a regional candidate R before₂Position of centre of gravity B₂Between distance D₃When having surpassed threshold value Th (S16), with a regional candidate R before₂Be defined as the zone C (S19) of contrast agent.That is, the addendum modification of center of gravity is converged to regional candidate R less than the maximum of threshold value Th₂Be chosen as specific zone C.

Like this, by being conceived to the displacement that the zone enlarges the position of centre of gravity that causes, can be subjected to the influence of CT value variable hardly, the zone C of extracting contrast agent accurately out.In addition, for the extraction of blood vessel wall too, change, can be subjected to the influence of CT value variable hardly, extract the area B of blood vessel wall accurately out by being conceived to the CT value.And then, for hematoblastic extraction too,, can be subjected to the influence of CT value variable hardly by the inboard such condition of blood vessel wall is set, extract hematoblastic regional A accurately out.

In addition,zone decision parts 27 also can use the k-mean method, and this rectangular histogram is categorized as 3 zones.By the k-mean method, obtain and be used to obtain each regional threshold value Th, make that the dispersion value of the CT value in each zone is equal.By determining each zone to make that the dispersion value of the CT value in each zone is equal, thereby the high material of similarity is included in the same area.

Fig. 6 represents to carry out sectional example by present embodiment, and the CT value with-100 to 537 is categorized as 3 zones.The pixel of CT value of scope with regional A is main corresponding with fatty part.The pixel of CT value of scope with area B is main corresponding with the part of blood vessel wall.The pixel of CT value of scope with zone C is main corresponding with hematoblastic part.

CTvalue transform parts 28 will determine the CT value of the pixel that 3 zones ofparts 27 extractions or classification comprise respectively to be replaced into each the regional eigenvalue that sets in advance by the zone.Thus, on display image, show the same area part, show can grasp each regional form with same brightness or color.

According to such present embodiment and since with the CT value show subregion accordingly image, the image of different materials such as the tissue that can grasp subject inside well, fat, contrast agent can be provided.In addition, automatically obtain the threshold value that is used to determine the zone, even therefore have under the situation of change, also can provide the image of having classified well in the CT value according to rectangular histogram.

In addition, in this embodiment, reducing behind the fuzzy composition (pseudomorphism composition) that produces around the high-contrast material, as object, therefore the processing of classifying can observe high-contrast material material on every side well with soft image.Have under support or the calcific situation in the blood capillary of the diameter of 5mm at the such 3mm that has of the coronary artery of heart especially, can observe the blood vessel wall around it, the savings state of fat, the state of contrast agent etc. well.

In addition, owing to the processing of classifying at the image that does not comprise the high-contrast material, add the information of high-contrast material then, so can carry out subregion to part well with low CT value.

In addition, the present invention has more than and is limited to the foregoing description, the implementation phase, in the scope that does not break away from its aim, can be out of shape and specialize element.In addition, a plurality of elements that disclosed by suitably making up the foregoing description can form various inventions.For example, can from the whole elements shown in the embodiment, delete several elements.And then, also can suitably make up the element among the different embodiment.

For example, in the above-described embodiments, use the k-mean method to obtain threshold value, but also can use group average method, other sorting techniques such as Ward method obtain threshold value.In addition, in the above-described embodiments, at having removed processings of classifying of high-contrast material and fuzzy image on every side thereof, but also can not such processing, and at the original image of region-of-interest, the processing of directly classifying, generation display image.

And then, in the above-described embodiments, the high-contrast location drawing is looked like to carry out addition, but also can not carry out addition, and only show soft image.In addition, the different labelling of color of also can overlapping demonstration representing the position of high-contrast material.

And then, in the above-described embodiments, X ray CT device has been described, but also can according to the medical image-processing apparatus that carries out pictorial display from the data for projection CT image of X ray CT device output etc., have implemented.And then, in the above-described embodiments, 2 dimension treatment of picture have been described, but also can have carried out the processing of 3 d image by a plurality of 2 dimension images are carried out above-mentioned processing.And then in the above-described embodiments, the pixel value that image has been described is the situation of CT value, but if the value of expression X ray attenuation quotient then also can be the value beyond the CT value.

According to the present invention, absorb at the X ray that shows the subject inside obtain by X ray CT device under the situation of distributed image, can be reduced in produce around the object of high X ray attenuation quotient fuzzy.

Claims (17)

Translated fromChinese

1.一种X射线CT装置，在上述X射线CT装置中收集与被检体有关的投影数据，根据上述收集到的投影数据而重构上述被检体的内部的图像，该X射线CT装置的特征在于包括：1. An X-ray CT apparatus, which collects projection data related to an object in the above-mentioned X-ray CT apparatus, and reconstructs an internal image of the above-mentioned object according to the projection data collected, the X-ray CT apparatus Features include:构成为从上述图像中抽出X射线衰减系数比较高的高对比度区域的单元；A unit configured to extract a high-contrast region with a relatively high X-ray attenuation coefficient from the above-mentioned image;构成为根据上述抽出的高对比度区域的位置和装置固有的点像强度分布函数，产生与上述高对比度区域有关的模糊图像的单元；A unit configured to generate a blurred image related to the above-mentioned high-contrast region according to the position of the extracted high-contrast region and the inherent point image intensity distribution function of the device;构成为为了产生与X射线衰减系数比较低的低对比度区域有关的低对比度图像，从上述图像减去上述模糊图像的单元，means for subtracting said blurred image from said image in order to generate a low-contrast image associated with a low-contrast region having a relatively low X-ray attenuation coefficient,与CT值对应地将上述低对比度图像分类为多个区域的单元；以及classifying the above-mentioned low-contrast image into units of a plurality of regions corresponding to the CT values; and将上述低对比度图像的像素值置换为上述分类了的多个区域各自固有的值的单元，Substituting the pixel values of the above-mentioned low-contrast image into units of values inherent to each of the above-mentioned classified regions,上述进行分类的单元具备：The units classified above have:根据多个阈值，从上述低对比度图像中抽出大小不同的多个区域的单元；Extracting units of multiple regions of different sizes from the above-mentioned low-contrast image according to multiple thresholds;计算上述抽出的多个区域各自的重心的单元；A unit that calculates the centers of gravity of the plurality of regions extracted above;根据上述重心之间的距离，从上述抽出的多个区域中选择与抽出对象物对应的特定的区域的单元，According to the distance between the above-mentioned centers of gravity, select the unit of the specific region corresponding to the extraction target object from the plurality of regions extracted above,上述进行选择的单元选择上述重心的变位量收敛为小于规定量的最大的区域作为上述特定的区域。The means for selecting selects, as the specific area, a region where the displacement amount of the center of gravity converges to a maximum value smaller than a predetermined amount.2.根据权利要求1所述的X射线CT装置，其特征在于：2. The X-ray CT apparatus according to claim 1, characterized in that:上述抽出高对比度区域的单元根据上述图像产生微分图像，通过对上述微分图像进行阈值处理，而抽出上述高对比度区域。The means for extracting the high-contrast area generates a differential image from the image, and extracts the high-contrast area by performing threshold processing on the differential image.3.根据权利要求1所述的X射线CT装置，其特征在于：3. The X-ray CT apparatus according to claim 1, characterized in that:上述产生模糊图像的单元具备：The above-mentioned unit for generating blurred images has:对上述抽出的高对比度区域的位置图像，卷积上述点像强度分布函数的单元；For the position image of the above-mentioned extracted high-contrast area, convolve the unit of the above-mentioned point image intensity distribution function;依照上述高对比度区域的标准CT值，对进行了卷积的高对比度区域的位置图像进行标准化的单元。A unit that normalizes the convolved high-contrast area position image according to the standard CT value of the above-mentioned high-contrast area.4.根据权利要求1所述的X射线CT装置，其特征在于：4. The X-ray CT apparatus according to claim 1, characterized in that:上述高对比度区域是为了治疗而埋入到被检体内的金属性的器具或石灰化了的钙。The above-mentioned high-contrast area is a metal instrument or calcareous calcium that is embedded in the subject for treatment.5.根据权利要求1所述的X射线CT装置，其特征在于还包括：5. The X-ray CT apparatus according to claim 1, further comprising:将上述抽出的高对比度区域的位置图像与上述低对比度图像相加的单元。A means for adding the position image of the extracted high-contrast region to the low-contrast image.6.根据权利要求1所述的X射线CT装置，其特征在于还包括：6. The X-ray CT apparatus according to claim 1, further comprising:将上述抽出的高对比度区域的位置图像与上述置换后的低对比度图像相加的单元。A means for adding the position image of the extracted high-contrast region to the replaced low-contrast image.7.根据权利要求1所述的X射线CT装置，其特征在于：7. The X-ray CT apparatus according to claim 1, characterized in that:上述分类了的多个区域包括主要是脂肪的区域、主要是血管壁的区域、主要是造影剂的区域。The multiple regions classified above include mainly fat regions, mainly blood vessel wall regions, and mainly contrast medium regions.8.根据权利要求1所述的X射线CT装置，其特征在于：8. The X-ray CT apparatus according to claim 1, characterized in that:根据与上述低对比度图像有关的每个CT值的像素出现的频度分布，决定上述多个阈值。The plurality of thresholds are determined based on the frequency distribution of appearance of pixels for each CT value related to the low-contrast image.9.一种X射线CT装置，在上述X射线CT装置中收集与被检体有关的投影数据，根据上述收集到的投影数据而重构上述被检体的内部的图像，该X射线CT装置的特征在于包括：9. An X-ray CT apparatus that collects projection data related to a subject in the above-mentioned X-ray CT apparatus, and reconstructs an image of the interior of the subject based on the collected projection data, the X-ray CT apparatus Features include:构成为为了产生与X射线衰减系数比较低的区域有关的低对比度图像，从上述图像减去与包含在上述图像中的X射线衰减系数比较高的区域有关的模糊图像的单元；means for subtracting, from said image, blurred images associated with areas of relatively high X-ray attenuation coefficient contained in said image, in order to generate a low-contrast image associated with areas of relatively low X-ray attenuation coefficient;与CT值对应地将上述低对比度图像分类为多个区域的单元；Corresponding to the CT value, the above-mentioned low-contrast image is classified into units of a plurality of regions;将上述低对比度图像的像素值置换为上述分类了的多个区域各自固有的值的单元，Substituting the pixel values of the above-mentioned low-contrast image into units of values inherent to each of the above-mentioned classified regions,上述进行分类的单元将上述低对比度图像分类为造影剂区域、血管壁区域和血小板区域，The classifying unit classifies the low-contrast image into a contrast agent region, a blood vessel wall region, and a platelet region,上述进行分类的单元为了确定上述造影剂区域，具备：In order to determine the above-mentioned contrast agent area, the above-mentioned classification unit has:根据多个阈值，从上述低对比度图像中顺序抽出内部包含的大小不同的多个区域候选的单元；According to a plurality of thresholds, sequentially extract a plurality of area candidate units with different sizes contained inside from the above-mentioned low-contrast image;计算上述抽出的多个区域候选各自的重心的单元；A unit for calculating the center of gravity of each of the plurality of region candidates extracted above;根据上述重心之间的距离，从上述抽出的多个区域候选中选择上述造影剂区域的单元，selecting a unit of the contrast agent region from the extracted plurality of region candidates based on the distance between the centers of gravity,上述进行选择的单元选择上述重心的变位量收敛为小于规定量的最大的区域作为上述造影剂区域。The means for selecting selects, as the contrast agent region, the largest region where the displacement amount of the center of gravity converges to be smaller than a predetermined amount.10.根据权利要求9所述的X射线CT装置，其特征在于：10. The X-ray CT apparatus according to claim 9, characterized in that:根据与上述低对比度图像有关的每个CT值的像素出现的频度分布，决定上述多个阈值。The plurality of thresholds are determined based on the frequency distribution of appearance of pixels for each CT value related to the low-contrast image.11.根据权利要求9所述的X射线CT装置，其特征在于：11. The X-ray CT apparatus according to claim 9, characterized in that:上述进行分类的单元为了确定上述血管壁区域，从上述低对比度图像的血管大致中心放射状地跟踪CT值，将上述CT值的变化超过规定值的2个位置确定为血管的内壁和外壁。The classifying means tracks CT values radially from the approximate center of the blood vessel in the low-contrast image in order to specify the blood vessel wall region, and identifies two positions where the change in the CT value exceeds a predetermined value as the inner wall and the outer wall of the blood vessel.12.根据权利要求11所述的X射线CT装置，其特征在于：12. The X-ray CT apparatus according to claim 11, characterized in that:上述进行分类的单元为了确定上述血小板区域，抽出上述血管壁内侧的、具有比上述血管壁低的CT值的像素群。The classifying means extracts a pixel group inside the blood vessel wall and having a CT value lower than that of the blood vessel wall in order to specify the platelet region.13.一种X射线CT装置，在上述X射线CT装置中收集与被检体有关的投影数据，根据上述收集到的投影数据而重构上述被检体的内部的图像，该X射线CT装置的特征在于包括：13. An X-ray CT apparatus, which collects projection data related to a subject in the above-mentioned X-ray CT apparatus, and reconstructs an image of the interior of the subject based on the collected projection data, the X-ray CT apparatus Features include:从上述图像中，根据多个阈值，顺序地抽出内部包含的大小不同的多个区域候选的单元；From the above image, according to multiple thresholds, sequentially extract a plurality of area candidate units with different sizes contained inside;计算上述抽出的多个区域候选各自的重心的单元；A unit for calculating the center of gravity of each of the plurality of region candidates extracted above;根据上述重心之间的距离，从上述抽出的多个区域候选中选择特定的区域的单元，According to the distance between the above-mentioned centers of gravity, select a unit of a specific region from the plurality of region candidates extracted above,上述进行选择的单元选择上述重心的变位量收敛为小于规定量的最大的区域作为上述特定的区域。The means for selecting selects, as the specific area, a region where the displacement amount of the center of gravity converges to a maximum value smaller than a predetermined amount.14.根据权利要求13所述的X射线CT装置，其特征在于：14. The X-ray CT apparatus according to claim 13, characterized in that:根据与上述图像有关的每个CT值的像素出现的频度分布，决定上述多个阈值。The plurality of thresholds are determined based on the frequency distribution of appearance of pixels for each CT value related to the image.15.一种图像处理装置，其特征在于包括：15. An image processing device, characterized in that it comprises:构成为从X射线图像中抽出X射线衰减系数比较高的高对比度区域的单元；A unit configured to extract a high-contrast region with a relatively high X-ray attenuation coefficient from the X-ray image;构成为根据上述抽出的高对比度区域的位置和装置固有的点像强度分布函数，产生与上述高对比度区域有关的模糊图像的单元；A unit configured to generate a blurred image related to the above-mentioned high-contrast region according to the position of the extracted high-contrast region and the inherent point image intensity distribution function of the device;构成为为了产生与X射线衰减系数比较低的低对比度区域有关的低对比度图像，从上述X射线图像减去上述模糊图像的单元，means for subtracting said blurred image from said X-ray image in order to generate a low-contrast image associated with a low-contrast region having a relatively low X-ray attenuation coefficient,与CT值对应地将上述低对比度图像分类为多个区域的单元；以及classifying the above-mentioned low-contrast image into units of a plurality of regions corresponding to the CT values; and将上述低对比度图像的像素值置换为上述分类了的多个区域各自固有的值的单元，Substituting the pixel values of the above-mentioned low-contrast image into units of values inherent to each of the above-mentioned classified regions,上述进行分类的单元具备：The units classified above have:根据多个阈值，从上述低对比度图像中抽出大小不同的多个区域的单元；Extracting units of multiple regions of different sizes from the above-mentioned low-contrast image according to multiple thresholds;计算上述抽出的多个区域各自的重心的单元；A unit that calculates the centers of gravity of the plurality of regions extracted above;根据上述重心之间的距离，从上述抽出的多个区域中选择与抽出对象物对应的特定的区域的单元，According to the distance between the above-mentioned centers of gravity, select the unit of the specific region corresponding to the extraction target object from the plurality of regions extracted above,上述进行选择的单元选择上述重心的变位量收敛为小于规定量的最大的区域作为上述特定的区域。The means for selecting selects, as the specific area, a region where the displacement amount of the center of gravity converges to a maximum value smaller than a predetermined amount.16.一种图像处理装置，其特征在于包括：16. An image processing device, characterized in that it comprises:构成为从X射线图像减去与包含在上述X射线图像中的X射线衰减系数比较高的区域有关的模糊图像，产生与X射线衰减系数比较低的区域有关的低对比度图像的单元；A unit configured to subtract a blurred image related to a region with a relatively high X-ray attenuation coefficient contained in the above-mentioned X-ray image from the X-ray image to generate a low-contrast image related to a region with a relatively low X-ray attenuation coefficient;与像素值对应地将上述低对比度图像分类为多个区域的单元；Classifying the above-mentioned low-contrast image into units of a plurality of regions corresponding to pixel values;将上述低对比度图像的像素值置换为上述分类了的多个区域各自固有的值的单元，Substituting the pixel values of the above-mentioned low-contrast image into units of values inherent to each of the above-mentioned classified regions,上述进行分类的单元具备：The units classified above have:根据多个阈值，从上述低对比度图像中抽出大小不同的多个区域的单元；Extracting units of multiple regions of different sizes from the above-mentioned low-contrast image according to multiple thresholds;计算上述抽出的多个区域各自的重心的单元；A unit that calculates the centers of gravity of the plurality of regions extracted above;根据上述重心之间的距离，从上述抽出的多个区域中选择与抽出对象物对应的特定的区域的单元，According to the distance between the above-mentioned centers of gravity, select the unit of the specific region corresponding to the extraction target object from the plurality of regions extracted above,上述进行选择的单元选择上述重心的变位量收敛为小于规定量的最大的区域作为上述特定的区域。The means for selecting selects, as the specific area, a region where the displacement amount of the center of gravity converges to a maximum value smaller than a predetermined amount.17.一种图像处理装置，其特征在于包括：17. An image processing device, characterized in that it comprises:根据多个阈值，从X射线图像中顺序抽出内部包含的大小不同的多个区域候选的单元；According to multiple thresholds, sequentially extract multiple area candidate units with different sizes contained inside from the X-ray image;计算上述抽出的多个区域候选各自的重心的单元；A unit for calculating the center of gravity of each of the plurality of region candidates extracted above;根据上述重心之间的距离，从上述抽出的多个区域候选中选择特定的区域的单元，According to the distance between the above-mentioned centers of gravity, select a unit of a specific region from the plurality of region candidates extracted above,上述进行选择的单元选择上述重心的变位量收敛为小于规定量的最大的区域作为上述特定的区域。The means for selecting selects, as the specific area, a region where the displacement amount of the center of gravity converges to a maximum value smaller than a predetermined amount.

Images