WO2017088263A1

WO2017088263A1 - Puncture planning path correction method and device

Info

Publication number: WO2017088263A1
Application number: PCT/CN2015/099650
Authority: WO
Inventors: 贾富仓; 肖德强; 罗火灵; 胡庆茂; 方驰华; 范应方; 杨剑
Original assignee: 中国科学院深圳先进技术研究院; 南方医科大学珠江医院
Priority date: 2015-11-23
Filing date: 2015-12-30
Publication date: 2017-06-01
Also published as: CN105411679B; CN105411679A

Abstract

A puncture planning path correction method and device, the method comprising: on the basis of an initial planning path, determine an initial entry point on the skin in a puncture region and set the initial entry point as a marker point (201); perform two successive CT scans of the puncture region to obtain an initial CT image and a second CT image (202); mark on the initial CT image an initial planning path; acquire position information of a mark point in the second CT image (203); perform registration on the initial CT image and the second CT image; on the basis of the position information of the marker point, determine the position of the marker point in the initial CT image after registration (204); obtain a distance vector of the marker point to the initial planning path (205); utilizing the distance vector of the marker point to the initial planning path, perform a translation transformation of the initial planning path, and set an intersection point of the transformed path and the puncture region on the skin as an actual entry point; on the basis of the actual entry point, and in accordance with the length of the initial planning path, determine a target point, and obtain a corrected puncture planning path (206). The puncture planning path correction device comprises: a marker point determining unit (401), a CT scanning unit (402), an initialization unit (403), a registration unit (404), a translation vector acquisition unit (405) and a correction unit (406).

Description

Puncture planning path correction method and device

The present application claims priority to Chinese Patent Application Serial No. No. No. No. No. No. No. No. No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No

Technical field

The present invention relates to the field of biomedical image technology, and in particular, to a method and apparatus for correcting a puncture planning path.

Background technique

One of the main indicators for measuring the accuracy of the puncture navigation system is the tip position error (TPE) of the tumor centroid to the tip of the puncture after the puncture is completed, and the TPE can be decomposed into two parts, as shown in Figure 1. The component along the direction of the puncture needle body is the radial component of the TPE, and the component perpendicular to the direction of the puncture needle body is the transverse component of the TPE. Among them, the lateral component of TPE is the most important. If the lateral component is too large, it must be re-pierced to correct the offset. Otherwise, only the insertion depth of the puncture needle needs to be adjusted to offset the error of the radial component of the TPE. Navigation error TPE calculation often needs to pass CT after the puncture and locate the position of the tumor and the position of the needle in the CT image, calculate the distance between the two to determine the size of the TPE and its lateral and radial components. If the navigation error is large, especially when the lateral component of the TPE is large, the puncture failure can be found after the first puncture, and then a second puncture must be performed to correct the navigation deviation. Multiple punctures will inevitably increase the chance of complications, and doctors rely on experience to make navigational deviation corrections will introduce large manual errors, and can not completely eliminate navigation bias. Therefore, in the case of large navigation error, a method for quantifying navigation error before puncture and automatic error correction is needed, which is used to improve the puncture navigation accuracy and reduce the navigation error, especially the TPE lateral component error.

At present, the correction of puncture navigation error is still a relatively new research topic. Most of the traditional error correction is after the puncture is completed. The doctor observes the puncture effect according to the postoperative CT image and roughly estimates the puncture deviation, and then relies on experience to correct and carry out the correction. The second puncture. Recently, Toporek et al. quantified the navigation error and visually presented it to the doctor for reference, including the lateral and radial components of the TPE, but after the initial puncture, the navigation error was quantified based on the location of the tumor and the tip of the CT image after the initial puncture. The initial puncture was not avoided, and the planning path was not corrected according to the navigation error to guide the doctor to perform the second puncture.

In summary, most of the research on the correction of puncture navigation error stays on the navigation error quantification, and does not propose a substantial solution to the error correction, and mainly when the navigation error is found after puncture, the doctor The navigation deviation is corrected and a second puncture is made.

Summary of the invention

For interventional navigation, the navigation error cannot be predicted before the puncture. Only after the first puncture, the doctor can correct the navigation deviation according to the postoperative CT estimation error and rely on experience, and then do the second puncture. In order to solve this technical problem, the present invention proposes a puncture planning path correction method and device, which can predict the navigation error without puncture, and correct the planning path according to the navigation deviation, and finally follow the corrected planning path. Puncture can greatly improve navigation accuracy.

To achieve the above object, the present invention provides a method for correcting a puncture planning path, including:

Determining an initial entry point on the skin of the puncture area according to the initial planning path, and setting the initial entry point as a marker point;

Performing two CT scans on the puncture area to obtain an initial CT image and a second CT image;

Marking an initial planning path on the initial CT image; acquiring location information of the marking point in the second CT image;

Registering the initial CT image and the second CT image; and determining a position of the marker point in an initial CT image after registration according to position information of the marker point;

Obtaining a distance vector of the marked point to the initial planning path;

In the initial CT image after the registration, the initial planned path is translated by using the distance vector of the marked point to the initial planning path, and the intersection of the transformed path and the skin of the puncture area is determined as the actual entry point. And determining a target point according to the length of the initial planning path according to the actual entry point, and obtaining a corrected puncture planning path.

To achieve the above object, the present invention also provides a puncture planning path correction device, comprising:

a marking point determining unit, configured to determine an initial entry point on the skin of the puncture area according to the initial planning path, and set the initial entry point as a marking point;

a CT scanning unit is configured to perform two CT scans on the puncture area in sequence to obtain an initial CT image and a second CT image;

An initializing unit, configured to mark an initial planning path on the initial CT image; and acquire location information of the marked point in the second CT image;

a registration unit, configured to register the initial CT image and the second CT image, and determine a position of the marker point in an initial CT image after registration according to position information of the marker point;

a translation vector acquisition unit, configured to obtain a distance vector of the marker point to the initial planning path;

a correcting unit, configured to perform a translation transformation on the initial planning path by using a distance vector of the marked point to the initial planning path in an initial CT image after registration, and an intersection of the transformed path and the skin of the puncture area The actual entry point is determined, and according to the actual entry point, the target point is determined according to the length of the initial planned path, and the corrected puncture planning path is obtained.

The above technical solution has the following beneficial effects: the technical solution can quantify the navigation error without puncture, and correct the initial planning path according to the navigation error, and the navigation offset correction by the doctor is more accurate and intuitive. At the same time, the technical solution is simple and versatile, and can be applied to various kinds of puncture navigation systems.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work.

Figure 1 is a schematic diagram of the decomposition of the puncture navigation error TPE;

2 is a flow chart of a method for correcting a puncture planning path according to the present invention;

3 is a schematic diagram of quantitative description of TPE lateral component error;

4 is a block diagram of a puncture planning path correction device provided by the present invention;

Figure 5 is a schematic diagram of a puncture planning path correction process;

6 is a functional block diagram of a registration unit in a puncture planning path correction device;

7a is a schematic diagram of an initial planned route of the embodiment;

Figure 7b is a schematic view showing the result of puncture according to the initial planned route of the embodiment;

Figure 7c is a schematic diagram of the route after correction according to the embodiment;

Fig. 7d is a schematic view showing the result of puncture according to the corrected route of the embodiment.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. Base All other embodiments obtained by those skilled in the art without creative efforts are within the scope of the present invention.

The working principle of the technical scheme: At present, most of the research on the correction of the puncture navigation error stays on the navigation error quantification, and does not propose a substantial solution to the error correction, and mainly when the navigation error is found after the puncture is large, the doctor according to the Experience corrects the navigation deviation and makes a second puncture. In view of the existing problems, the technical solution solves the problem of quantifying the navigation error before puncture, and corrects the planning path according to the quantized error, so that the navigation error can be corrected before the puncture, so that the precise planning path is corrected according to the revised planning path. Doctor puncture.

The technical solution is an automatic correction method for the planning path, which is used for improving the precision of the puncture navigation. Find the entry point location according to the initial planning path before navigating the puncture, and mark the patient on the patient, then perform a secondary CT scan, then extract the position of the marker point and transform it into the initial CT image, in the initial CT image. Calculate the distance vector from the marker point to the initial planning path, then use the vector to translate the initial planning path, search for the new puncture path entry point and end point based on the translated path and patient CT surface data, and finally use the new planning path to guide the doctor. puncture.

Based on the above working principle, the present invention proposes a puncture planning path correction method, as shown in FIG. 2 . include:

Step 201): determining an initial entry point on the skin of the puncture area according to the initial planning path, and setting the initial entry point as a mark point;

Step 202): performing two CT scans on the puncture area in sequence to obtain an initial CT image and a second CT image;

Step 203): marking an initial planning path on the initial CT image; acquiring location information of the marking point in the second CT image;

In step 201, step 202, step 203, before the puncture navigation starts, the entry point is found on the patient according to the initial planning path, and the marker point is pasted here, then the patient is subjected to a second CT scan, and finally from the second The position information of the marker points is manually extracted in the CT image.

Step 204): registering the initial CT image and the second CT image; and determining a position of the marker point in an initial CT image after registration according to position information of the marker point;

Step 205): obtaining a distance vector of the marked point to the initial planning path;

In step 204 and step 205, first, registration is performed between the initial CT image and the second CT image, and then the marker points in the second CT image are transformed into the initial CT image. Here, the CT image registration is realized by using the marker points for rigid body registration, that is, selecting a plurality of corresponding anatomical landmark points in the vicinity of the marker points in the two images to perform rigid body matching.

Rigid body registration or rigid body matching refers to the registration between two images by rigid body transformation. The present invention transforms the second CT image into the initial CT image space by using rigid body transformation, and each pixel in the transformed second CT image. The relative distance between the points does not change in the initial CT image, that is, the overall topology does not change after the second CT image is transformed.

The distance vector from the marker point to the initial planning path is then calculated in the initial CT image, ie the translation vector to eliminate the navigation error. As shown in FIG. 3, it is a schematic diagram for quantifying the TPE lateral component error. The size of the translation vector is equal to the magnitude of the lateral component of the navigation error TPE, and the application of the translation vector to the initial path can effectively reduce the lateral component error of the TPE, thereby greatly improving the navigation accuracy.

Step 206): in the initial CT image after registration, using the distance vector of the marker point to the initial planning path, performing translation transformation on the initial planning path, and the intersection of the transformed path and the skin of the puncture area For the actual entry point, according to the actual entry point, the target point is determined according to the length of the initial planned path, and the corrected puncture planning path is obtained.

In step 206, after the navigation error (TPE lateral error) is quantized, the initial translation path is translated by using the obtained translation vector, and a new entry point is searched on the skin of the puncture area according to the transformed path, and the point is after translation. The path entry point, once the entry point is determined, the target of the new path can be determined according to the length of the initial planned path, and finally the corrected puncture planning path is obtained.

Correspondingly, based on the above working principle, the present invention also provides a puncture planning path correcting device, as shown in FIG. The function of each functional module of the puncture planning path correction device will be described with reference to FIG. The puncture planning path correction device comprises:

a marker point determining unit 401, configured to determine an initial entry point on the skin of the puncture region according to the initial planning path, and set the initial entry point as a marker point;

The CT scanning unit 402 is configured to perform two CT scans on the puncture area in sequence to obtain an initial CT image and a second CT image;

An initializing unit 403, configured to mark an initial planning path on the initial CT image, and acquire location information of the marked point in the second CT image;

a registration unit 404, configured to register the initial CT image and the second CT image, and determine a position of the marker point in an initial CT image after registration according to position information of the marker point ;

a translation vector obtaining unit 405, configured to obtain a distance vector of the marked point to the initial planning path;

a correcting unit 406, configured to perform a translation transformation on the initial planned path by using a distance vector of the marked point to the initial planning path in an initial CT image after registration, and the transformed path and the skin of the puncture area Pay The point is determined as an actual entry point, and according to the actual entry point, the target point is determined according to the length of the initial planned path, and the corrected puncture planning path is obtained.

Among them, as shown in FIG. 6, it is a functional block diagram of the re-alignment unit of the puncture planning path correction device. The registration unit 404 includes:

An anatomical landmark point determining module 4041, configured to determine a plurality of anatomical landmarks in regions near the marked points in the two CT images, respectively;

The rigid body matching module 4042 is configured to match the anatomical landmarks of the initial CT image with the anatomical landmarks of the second CT image.

Using the above technical solution, verification was carried out by a phantom puncture experiment. As shown in Figures 7a to 7d. In Figure 7a, the dark lines are the initial planning paths. Figure 7b shows the results of the puncture according to the initial planning path shown in Figure 7a. In Figure 7b, the black globules are tumor targets. In Figure 7c, the dark lines are the initial planning paths and the light lines are the corrected paths. Figure 7d shows the results of puncture according to the corrected path. Experiments show that based on the original puncture navigation system, the introduction of this scheme to automatically correct the planning path can effectively improve the accuracy of puncture navigation. And, in the early stage, there is no need to perform a puncture attempt. No additional trauma to the patient.

The specific embodiments of the present invention have been described in detail with reference to the preferred embodiments of the present invention. All modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

A puncture planning path correction method, comprising:

Determining an initial entry point on the skin of the puncture area according to the initial planning path, and setting the initial entry point as a marker point;

Performing two CT scans on the puncture area to obtain an initial CT image and a second CT image;

Marking an initial planning path on the initial CT image; acquiring location information of the marking point in the second CT image;

Registering the initial CT image and the second CT image; and determining a position of the marker point in an initial CT image after registration according to position information of the marker point;

Obtaining a distance vector of the marked point to the initial planning path;

In the initial CT image after the registration, the initial planned path is translated by using the distance vector of the marked point to the initial planning path, and the intersection of the transformed path and the skin of the puncture area is determined as the actual entry point. And determining a target point according to the length of the initial planning path according to the actual entry point, and obtaining a corrected puncture planning path.
The method of claim 1 wherein said step of registering comprises:

Determining a plurality of anatomical landmarks in the vicinity of the marked points in the two CT images;

An anatomical landmark corresponding to the initial CT image is matched with an anatomical landmark of the second CT image.
The method of claim 1 wherein the magnitude of the distance vector is equal to the magnitude of the lateral component of the navigation error.
A puncture planning path correction device, comprising:

a marking point determining unit, configured to determine an initial entry point on the skin of the puncture area according to the initial planning path, and set the initial entry point as a marking point;

a CT scanning unit is configured to perform two CT scans on the puncture area in sequence to obtain an initial CT image and a second CT image;

An initializing unit, configured to mark an initial planning path on the initial CT image; and acquire location information of the marked point in the second CT image;

a registration unit, configured to register the initial CT image and the second CT image, and determine a position of the marker point in an initial CT image after registration according to position information of the marker point;

a translation vector acquisition unit, configured to obtain a distance vector of the marker point to the initial planning path;

a correcting unit, configured to perform a translation transformation on the initial planning path by using a distance vector of the marked point to the initial planning path in an initial CT image after registration, and an intersection of the transformed path and the skin of the puncture area The actual entry point is determined, and according to the actual entry point, the target point is determined according to the length of the initial planned path, and the corrected puncture planning path is obtained.
The apparatus of claim 4 wherein said registration unit comprises:

An anatomical landmark point determining module for determining a plurality of anatomical landmarks in the vicinity of the marked points in the two CT images;

The rigid body matching module is configured to match the anatomical landmarks of the initial CT image with the anatomical landmarks of the second CT image.
The apparatus according to claim 4, wherein the magnitude of the distance vector obtained by the translation vector acquisition unit is equal to the magnitude of the lateral component of the navigation error.