CN1194134A - Computerised boundary estimation in medical images - Google Patents

Abstract

A computerised boundary estimation technique (using prostate as an example) in medical images (ultrasound in particular), called Radial Bas-relief, is disclosed. The image probe can be carried by a robot and shares the same reference frame as the robot. The prostate is scanned and the ultrasound images are fed into a computer which provides computational images processing. Such a method is employed to allow a quick and robust extract of the boundary of interest from transverse images taken transurethrally or transrectally or otherwise.

Description

The computerized border assessment of medical images

The present invention generally is about Medical image Processing, more specifically, be about using the radially interior operation ultrasonic scanning of bottom concavo-convex (RBR) method for excising prostate automatically, this method can be fast and is extracted prostate border in the per urethra imaging reliably, according to the present invention, this method is used for automatically delineating out the prostate borderline region, and the result that ultrasonic image is handled is used for per urethra and automatically excises prostate.

In the past ten years, it is very active that the process of robotic surgical becomes, in the nineties, having developed many surgical operation robots attempted in the surgery experiment with their central some, by Ng Wan Sing and Davies B, example as active robotic surgical is disclosed in the article of " robotic surgical-in the first-hand experience of TURP " that people such as L delivered in 12 (1) pages of 120-125 of IEEEEngineering in Medicine and Biological magazine in March, 1993, prostate excision work automatically, this article suggestion, prostatic urethra excision method are the most frequently used methods of removing the urine outflow obstacle of bladder at present.This process comprises per urethra introduction sickle, extends sickle and enters prostate, and Shun Xu cutting can be performed to remove adenoma there, and this adenoma is the body of prostate augmenting portion.As the part that the male increases with the year order, prostatic body of gland increase has taken place inevitably, and this has just caused dysuria.Must be near the adenoma of seminal colliculus by exenterate to alleviate obstacle, be called as the surgical operation auxiliary robot of " SARP " prostate excision-device be used and carry out automatic prostatectomy.SARP is a special case, has developed the special roll-over protective structure that is fit to kinematic configuration in this special case, to produce the hole of cutting of a plurality of gardens taper or tubbiness in prostate, does not resemble many other systems, and SARP is active surgical operation robot.The advantage of being drawn by the robot manipulation of SARP is that the location is reliable and save time.These advantages are important in operation, this has guaranteed reliably that because of (i) location excision will not be that to point to undesirable zone and securing position under the ignorant situation be in inside or external sensor is determined (example as internal sensor can be to be fixed on each in conjunction with the optical encoder on the motor, can be light/magnetic tracking means as the example of external sensor); (ii) the minimizing of time can for example repeatedly detect important sign or characteristics and carefully observe tissue texture as some of new folding cutting result by remote control ground; The sensed image of dissecting around the memory is realized (saving of the time of being realized by high-speed electric expreess locomotive has directly reduced time and the narcotic absorbtivity of patient in anesthesia) continuously.

In automatic prostate excision system, surgical doctor three parts common and system interact; (1) computer and its auxiliary monitor scope; (2) endoscope's display unit and (3) switch storehouse and light emitting diode show.In automatic prostate excision system, in order to allow robot system see the direct environment content in addition that endoscope provides, use of robot system of ultrasonic image and conduct operation, ultrasound probe, the per urethra type, advanced to the cervical region of blade and under accurate step, return then, the prostatic flyback retrace that comes is arranged in these steps, prostatic border is marked, the border of capsule/adenoma, be that border between the tissue of capsule and amplification is positioned within the prostatic border, the border pro-edge joint of capsule/adenoma touches prostatic border and slightly from it backward.

Because between the scanning is that known and ultrasonic probe axle is that they are common at interval, can carry out three-dimensional reproduction.The three-dimensional ultrasonic system of acquisition in real time and demonstration three dimensions volume data is described and is shown in the middle of " the edge virtual target that has real world: see ultrasonic image in the patient body " literary composition, this article is by Michael Bajura, Henry Fuchs and Ryutarou Ohbuchi are published in the computer generalization surgical operation of being edited by R Taylor, published in 1996, this article discloses, (1) obtains and perspective has the real-time ultrasound wave datum of known location and by the algorithm of external sensor track and localization, (2) produce the work virtual environment, this virtual environment obtains in real time and shows that three-D ultrasonic wave datum and (3) recovery are from the structural information of ultrasound data in particular for the volume perspective.Subsequently, the countermeasure according to maximized excision can be planned to cut can produce the recess of a plurality of tapers or tubbiness with this, stays competent place in the back of true quantitative adenoma to obtain the execution of receivable back operation.

Under computer auxiliary, many visual methods all are feasible, CT for example, MRI and ultrasonic.Compare with CT and MRI image or from the photo image of microscope photograph, ultrasonic image is handled more difficult, and this is because spark, the existence of noise and relatively poor resolution.Extract boundary information or further feature, for example the ultrasonic image segmentation of tumor is the theme of research already.Yet ultrasonic image is better than other form.As CT and MRI form, this will take much time in order to obtain high-resolution image.Initial and maintenance cost is very high.They are can not convenience and safe use in operation not have meticulous measure.Current transurethral ultrasonic image hands preface is to be the expense labour under the highly manual situation.Because scanning before operation, do, when robot when patient uses on one's body, deposit the operation before and the operation among data this great difficulty is arranged.Used ultrasonicly in SARP, this is because its low relatively expense and facility, because it can introduce operating room and easily because it does not cause patient's untoward reaction.

Ultrasonic image and the processing system used by SARP are to be furnished with the B﹠amp of 7MHz and 5.5MHz probe; K type 1846 type scanners.This PS is to use to determine prostatic size among diagnosis type scanner and the first arrival SARP.Scan prostate to and fro by the operation front sequence and finish definite size.Being stacked in continuously on the ibm computer of continuous transverse scanning reproduced to form prostatic threedimensional model.

In order to realize the assessment on prostatic border apace, comprise and calculate that ground reproduces threedimensional model and based on the order excision plan of this model, the present inventor has avoided common picture element analysis one by one and introduced the radially concavo-convex method in bottom.The bottom is concavo-convex to be the darkroom technology of using during taking pictures, and by Langhord, the New York that M writes " Alhred A Knopl company goes out " progressively guide to learn to shine to disclose in the handbook that resembles art and shining the concavo-convex method in the bottom of using in the art that resembles.According to the present invention, on the prostatic border of assessment or other when organizing, radially bottom concavo-convex (RBR) method is found to be useful.Just as concavo-convex image bottom having finished to reversed image, little go out depositor by stack, and resembling just like the very low concavo-convex engraving that illuminates from a side of printing off.The image that produces will be reduced to the model of line and the tone of sheet.The image edge of this sample loading mode can be highlighted.

The present invention is medical images (specific is a ultrasonic) processing method, and this method can obtain the size of accurate prostate (using prostate to be example).According to the present invention, it also discloses a kind of simple method prostatic border of assessment of going to use a computer.According to the preferred embodiment of the invention, use robot system to finish the ultrasound scan method of prostatectomy, this robotic surgical device includes the head axle, computer, 4 motion controllers, ultrasonic scanner and pass the per urethra type ultrasonic probe of the resectoscope that is fixed on the said surgical operation robot, this method may further comprise the steps:

(a) connect said resectoscope to the said robot of the isostatic door type frame of the reference position that is suspended in former state (being called as the seminal colliculus position);

(b) prostate of the head axle scanning patient by moving the said surgical operation robot be fixed with said ultrasonic probe;

(c) will present to said frame extractor and the said image of digitized at the scanned picture that the step (b) obtains and handle so that computational picture to be provided; With

(d) delineate out prostate according to the present invention by computer, use the computerized estimation of the ultrasonic image of the concavo-convex method in bottom radially and then may further comprise the steps:

(a) the prostatic ultrasonic image of upset is to obtain the image of upset;

(b) on orthogonal direction, amplify the image of said upset pro rata to obtain the image of amplification;

(c) image of the said amplification that obtains in f step is added to the said ultrasonic image that obtains in claim 1 has the gray level of strengthening marginal information with generation the concavo-convex image in bottom;

(d) dualization goes on foot the concavo-convex image in bottom of acquisition to remove gray level at (g);

(e) expansion and erosion (h) double image are to obtain the profile of prostate boundary graph; With

(f) image that thinning is expanded or erosive (i) goes on foot is to provide the skeleton contour line.

With this, the border of capsule has been determined by prostatic border like this.

According to this, the purpose of this invention is to provide the ultrasonic image processing method, wherein the ultrasonic probe of Shou Shu resectoscope and scanning is carried by robot, makes them can be total to prosperous identical reference frame as robot.

Another object of the present invention provides a ultrasonic image processing method of carrying out the prostate excision method automatically, wherein can remove meticulous patient's record (coupling of data before the operation and in the operation) from by jointly reference picture system and robot.

Another object of the present invention provides the method that the ultrasonic image of automatic prostate excision method is handled, and wherein catches and handle each used time of scanning to have shortened.

Another object of the present invention provides the method for the ultrasonic image processing of automatic prostate excision method, wherein uses balanced door type frame to make and sets up the step of robot to simplify greatly.

By to description, accessory claim and the description of the drawings that accompanies, these and other characteristics of the present invention, the parties concerned and advantage will be further appreciated.

Fig. 1 shows the configuration according to computer assisted ultrasonic image device of the present invention;

Fig. 2 shows according to the external form figure to the surgeon's auxiliary robot that is used for urinary disturbance selected of the present invention;

Fig. 3 shows according to transurethral prostatic typical laterally ultrasonic scanning of the present invention;

Fig. 4 shows the simple oppositely image according to Fig. 3 of the present invention;

Fig. 5 shows according to the present invention the image of Fig. 4 is added to the image of Fig. 3 and resembling of obtaining;

Fig. 6 shows dual (binarised) image according to Fig. 5 of the present invention;

Fig. 7 shows according to the present invention by expanding and corroding resembling of level and smooth Fig. 6;

Fig. 8 shows the image on the capsule border of extracting according to the present invention; With

Fig. 9 shows the x-y coordinate formula according to typical capsule/adenoma of the present invention.

Referring to Fig. 1, show the sketch plan that is called as the area of computer aided ultrasonic image system of surgeon's auxiliary robot of selectivity urinary disturbance or " SARUD " here.This system comprises personal computer 10, is furnished with frames in high speed extractor (12) and is furnished with hardware enforcement image processing function, and is for example reverse, the motherboard that increases and amplify or dwindle, 4 motion controllers 14, surgical operation robot 16, ultrasonic scanner 18 and per rectum or transurethral probe 20.Ultrasonic scanner 18 can be chosen from Bruel and Kjoer type 1846 scanning devices or Krez combined 430.Can per-rectum ultrasonic probe of clamping or transurethral ultrasonic probe 20 with the robot 16 that equilibrium is hung in the preferred embodiment of the present invention.4 motion controllers 14 provide the motion of 4 axles, i.e. a kinematic axis (linear axes), and annulate shaft (rotation), arc axle (rotation) and oscillation center length drives axle (linear).Axle is not by this fixed order.Fig. 2 schematically shows the figure according to robot 16 of the present invention.Among the figure: d1: move horizontally building-out cable length; D2: the vertical building-out cable length that moves with rotation; A: rapid release cable connector; B: communication path; C: motion controller; H: main frame; T1 is used to make the fastening machines of this medical apparatus to cover the pliable and tough of all cables flexibly; T2: the signal and the flexible catheter that are used for the main control cable of robotic surgical device; T3: ground pipe.According to shown in Figure 2, transurethral probe 20 is by the crust of resectoscope 22.(unshowned) adapter is used to provide resectoscope 22 to fix to the rigidity in the robot 16.There is the different adapter (not shown) of skew to be used as transrectal probe with the central shaft of resectoscope 22.As shown in Figure 2, when reference position (sign of dissection is called as mons pubes) is found by endoscope and is interference-free, resectoscope is connected in the robot 16, robot 16 hangs on the balanced door frame and the tool holder of particular design is used to fix, patient is being carried out before the operation, using to have the transurethral ultrasonic scanning of SARUD or transrectal ultrasonography that use has SARUD scans prostate.Only partly comprise the ultrasonic probe 20 of horizontal fixed and its adapter (not shown) with all the other of delivery robots arm when the head axle motion of robot 16, make the transverse section of a large amount of glands be scanned, and begin to point to mons pubes from the blade cervical region.

Before the scanning beginning, before the head of the following robot 16 of manual control is shifted to, the prostatic length of measuring from mons pubes to the blade neck will obtain by endoscope.Above-mentioned method has utilized the tool clamp holder of robot 16 to fix the resectoscope of operation and the ultrasonic probe 20 of scanning simultaneously.The shell of resectoscope is stayed in patient's the urethra in scanning and excision process all the time.This has just determined, the reference axis of image falls within the line of ring-like axle, and it is parallel with the head axle of robot 16, be the result of excision as identical being used, deposit operation data preceding and operating room and just there is no need, the reference frame of having done scanning and visual reference frame and robot at operating room is identical.

When scanning was finished, the cutting part (not shown) was introduced into and is attached on the shell of resectoscope 22, and left target location and robot 16 alone, and they all effectively are rigidly fixed to uses on balanced door frame and the structure.

In scan period, ultrasonic image is fed to frame extractor (12), and its digital ultrasound image can be used in computer image treatment.Each profile scanning is hunted down and is presented on the monitor and the purpose that keeps as file and being stored.

By the use light pen, or introduce automatic capsule depiction program and remove outline, all prostate borders all can be delineated out by surgeon or trained personnel (operation of its control and supervisory computer).

Importantly reduce the time of TURP, patient will be anaesthetized without undergoing crossing for a long time.The minimizing that same anaesthetic absorbs will avoid resembling the complex situations of dyspnea and hemodilution.And then this also reduces blood loss.Delineate the border of capsule by hand, this is very time taking, when particularly the surgeon does not have experience to reading sound spectrograph.This depends on prostatic length and required precision and resolution, and this is easy to surpass 10 sections, and each section all needs to describe the border of capsule.Because this trend, robot 16 should finish whole surgery being less than in 30 minutes, wishes with regard to the utmost point that so scanning was finished in 5 to 8 minutes, stays time enough and uses for operation.

According to the present invention, our hope is to see, the automatic solution of the sketch outline task under the help of computer.Developed according to the novelty variation that resembles the concavo-convex method in known so-called bottom in the technology, its allows to extract prostatic border rapidly and reliably from the section image of clapping by urethra.The bottom is concavo-convex to be a process, can be added on the egative film by this process 3-D effect, is removed in order to provide undesirable part clearly visual and that one of desirable profile is detected in the memorizer of computer.Based on the scanning of neighbouring part, will be inferred near the needed unavailable information of prostate profile.

Fig. 3 shows the typical prostate section ultrasonic scanning that per urethra is taken.Prostatic border marks with white arrow.The border of capsule/adenoma, the boundary of the tissue of capsule and amplification (" adenoma ") is located within the prostatic border.Adenoma is removed with surgical operation.As shown in FIG., this clearly exists an object here, and promptly stone has enough density in the place that indicates " X ".Fig. 4 shows the reverse image of Fig. 3 ultrasonic image.Oppositely image is amplified pro rata at orthogonal direction.The reverse image of this amplification is added to initial image then.The result who adds is shown in Figure 5, as can be seen from Figure 5, round the band at edge since oppositely face greater than primary image, the result of RBR method that Here it is.Use is called as the most basic digital image operation of dualization, and image is further processed to remove grey level.Double image is shown in Fig. 6.In order to obtain the more level and smooth contour line of capsule, dual image has stood the computing of so-called " expansion " and " erosion ".This operates in, and the profile band has been filled many " duck eye " (as shown in Figure 7) so that the next operation that is called skeletonizing or thinning becomes easy.Fig. 8 shows the border of the capsule that extracts after thinning.Be somebody's turn to do the operation of " expansion " and erosion operations and skeletonizing and can use the imgae processing software bag, for example can finish from " Optimas " that Bioscan company buys.

The object that indicates " X " will be created in the echo that radial direction and all useful informations intersect.See in Fig. 8 that also they are derived as short branch skill (also being long branch sometimes) from desirable border.Use deduction and some type branches to obtain profile shown in Figure 9.And then, having put in order size will have to calibrate to compensate reverse amplification with suitable amount, according to the present invention, radially the bottom is concavo-convex can benefit from for example grey level standardization or the like of common visual pretreatment (in the pixel processing one by one of the interested zone that is defined).To not work there being under the situation of robot platform the radially concavo-convex processing in bottom.

This clearly can make various variations and modification to medical visual method, but these variations and being modified in do not break away from the spirit and scope of the invention of determining in the appended claims and can make.

Claims (8)

1, uses the radially concavo-convex method in bottom, in medical image, to carry out the method for border assessment, this method comprises the robotic surgical device that has the head axle, the computer of being furnished with the frame extractor, 4 mobile controllers, ultrasonic scanner and per urethra type or per rectum type ultrasonic probe, this probe be by being fixed on the resectoscope crust in the said robot, and this method comprises that (a) connects in the said robot of said resectoscope to the isostatic door frame that hangs on the position without disturbance (being called mons pubes); (b) scan by head a destination organization that moves the said robotic surgical device that has been fixed with said ultrasonic probe patient; It is characterized in that the image of the scanning that obtains in (b) is fed to said frame extractor, said destination organization image is digitized then image processing to be provided and to delineate out profile by computer.

2, concavo-convex method further may further comprise the steps the method that medical image carries out the border assessment bottom the use of claim 1 radially:

(c) the medical image of counter-rotating destination organization is to obtain reverse image;

(d) on orthogonal direction, amplify the said reverse image of image in proportion to obtain to amplify;

(e) the said medical image that the image that adds the said amplification that obtains in (d) obtains in the claim 1 has the concavo-convex image in bottom of the gray level of enhanced marginal information with generation;

(f) dualization in (e) the concavo-convex image in said bottom that obtains to remove gray level;

(g) expand and corrode the double image that obtains at (f) to obtain the more level and smooth profile on destination organization border; With

(h) thinning in (g), expand or erosive image so that the profile of skeletonizing to be provided.

3, claim 1 or 2 the use concavo-convex method in the bottom method of carrying out the assessment of computerized border in medical image radially, wherein, the border of destination organization is to use light pen to be delineated out on monitor screen.

4, claim 1 or 2 the use concavo-convex method in the bottom method of carrying out the assessment of computerized border in medical image radially, wherein, the destination organization border is delineated out by automatic capsule depiction program.

5, claim 1 or 2 the use concavo-convex method in the bottom method of in medical image, carrying out the assessment of computerized border radially, wherein, cutting element be introduce and be attached on the crust of resectoscope.

6, claim 1 or 2 the use concavo-convex method in the bottom method of carrying out the assessment of computerized border in medical image radially, wherein, destination organization is a prostate.

7, the method that concavo-convex method is carried out the assessment of computerized border bottom the use of claim 3 radially in medical image, wherein, destination organization is a prostate.

8, the method that concavo-convex method is carried out the assessment of computerized border bottom the use of claim 4 radially in medical image, wherein, destination organization is a prostate.

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